Encapsulated proppants

DOEpatents

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Roberts, Jeffery James; Spadaccini, Christopher M.; Stolaroff, Joshuah K.

2018-01-09

A capsule for carrying a proppant for emplaced in a formation containing formation fluid by a hydraulic fracture operation using a fracturing fluid. The capsule includes a capsule body. The capsule body includes a proppant. There is a surface layer on the capsule body that is permeable to the formation fluid or the fracturing fluid or is permeable to both the formation fluid and the fracturing fluid. The proppant material is dry cement that interacts with the formation fluid or the fracturing fluid or both the formation fluid and the fracturing fluid that migrate through the surface layer and is taken up by the dry cement causing the dry cement to harden.

Systematics of Alkali Metals in Pore Fluids from Serpentinite Mud Volcanoes: IODP Expedition 366

NASA Astrophysics Data System (ADS)

Wheat, C. G.; Ryan, J.; Menzies, C. D.; Price, R. E.; Sissmann, O.

2017-12-01

IODP Expedition 366 focused, in part, on the study of geo­chemical cycling, matrix alteration, material and fluid transport, and deep biosphere processes within the subduction channel in the Mariana forearc. This was accomplished through integrated sampling of summit and flank regions of three active serpentinite mud volcanoes (Yinazao (Blue Moon), Asùt Tesoro (Big Blue), and Fantangisña (Celestial) Seamounts). These edifices present a transect of depths to the Pacific Plate, allowing one to characterize thermal, pressure and compositional effects on processes that are associated with the formation of serpentinite mud volcanoes and continued activity below and within them. Previous coring on ODP Legs 125 and 195 at two other serpentinite mud volcanoes (Conical and South Chamorro Seamounts) and piston, gravity, and push cores from several other Mariana serpentinite mud volcanoes add to this transect of sites where deep-sourced material is discharged at the seafloor. Pore waters (149 samples) were squeezed from serpentinite materials to determine the composition of deep-sourced fluid and to assess the character, extent, and effect of diagenetic reactions and mixing with seawater on the flanks of the seamounts as the serpentinite matrix weathers. In addition two Water Sampler Temperature Tool (WSTP) fluid samples were collected within two of the cased boreholes, each with at least 30 m of screened casing that allows formations fluids to discharge into the borehole. Shipboard results for Na and K record marked seamount-to-seamount differences in upwelling summit fluids, and complex systematics in fluids obtained from flank sites. Here we report new shore-based Rb and Cs measurements, two elements that have been used to constrain the temperature of the deep-sourced fluid. Data are consistent with earlier coring and drilling expeditions, resulting in systematic changes with depth (and by inference temperature) to the subduction channel.

Petrophysical Properties of the Yeso, Abo and Cisco Formations in the Permian Basin in New Mexico, U.S.A

NASA Astrophysics Data System (ADS)

Mann, Griffin

The area that comprises the Northwest Shelf in Lea Co., New Mexico has been heavily drilled over the past half century. The main target being shallow reservoirs within the Permian section (San Andres and Grayburg Formations). With a focus shifting towards deeper horizons, there is a need for more petrophysical data pertaining to these formations, which is the focus of this study through a variety of techniques. This study involves the use of contact angle measurements, fluid imbibition tests, Mercury Injection Capillary Pressure (MICP) and log analysis to evaluate the nano-petrophysical properties of the Yeso, Abo and Cisco Formation within the Northwest Shelf area of southeast New Mexico. From contact angle measurements, all of the samples studied were found to be oil-wetting as n-decane spreads on to the rock surface much quicker than the other fluids (deionized water and API brine) tested. Imbibition tests resulted in a well-connected pore network being observed for all of the samples with the highest values of imbibition slopes being recorded for the Abo samples. MICP provided a variety of pore structure data which include porosity, pore-throat size distributions, permeability and tortuosity. The Abo samples saw the highest porosity percentages, which were above 15%, with all the other samples ranging from 4 - 7%. The majority of the pore-throat sizes for most of the samples fell within the 1 - 10 mum range. The only exceptions to this being the Paddock Member within the Yeso Formation, which saw a higher percentage of larger pores (10 - 1000mum) and one of the Cisco Formation samples, which had the majority of its pore sizes fall in the 0.1 - 1 mum range. The log analysis created log calculations and curves for cross-plot porosity and water saturation that were then used to derive a value for permeability. The porosity and permeability values were comparable with those measured from our MICP and literature values.

Timing of fluid seepage on summits of Quaker and Conical serpentine mud volcanoes, Mariana forearc: Evidence from U/Th dating of carbonate chimneys

NASA Astrophysics Data System (ADS)

Tong, Hongpeng; Fryer, Patricia; Feng, Dong; Chen, Duofu

2017-04-01

Serpetinization of forearc mantle along deep faults in the Mariana convergent plate margin permits formation of large active serpentinite mud volcanoes on the overiding plate within 90 km of the trench. Fluid seepage on summits of the mud volcanoes lead to the formation of authigenic carbonate chimneys close to the seafloor. Such carbonate chimneys are unique archives of past fluid seepage and assciated envrionemtnal parameters. Here, we report U/Th dating and stable carbon and oxygen isotopes of the chimneys from Quaker and Conical serpentine mud volcanoes. The resulting U/Th ages of samples from Quaker Seamount show three time intervals of 11,081 to10,542 yBP, 5,857 to 5,583 yBP, and 781 to 164 yBP, respectively. By comparison, carbonates from Conical Seamount have U/Th ages between 3,070 yBP and 1,623 yBP. Our results suggest that fluid seepage on the summits of serpentine mud volcanoes are episodic and probably locally controlled. Samples from Quaker seamount show depletion of 13C (δ13C=-7.0-0.4‰ V-PDB), indicating contribution of carbon from anoxic oxidation of abiogenic methane. By contrast, samples from Conical seamount have positive δ18O values (0.6-6.3), suggesting enrichment of 18O in the seepage fluid. The data obtained provide time integrated variation of seepage fluids and seepage dynamics that are archived in authigenic carbonates. This finding adds to the ongoing multidisciplinary effort to better constrain the environment in the Mariana forearc region and to determine the locally dominant biogeochemical processes. Acknowlegment: This study was funded by the CAS (Grant No. XDB06030102).

Understanding Copper Isotope Behavior in the High Temperature Magmatic-Hydrothermal Porphyry Environment

NASA Astrophysics Data System (ADS)

Gregory, Melissa J.; Mathur, Ryan

2017-11-01

Copper stable isotope geochemistry has the potential to constrain aspects of ore deposit formation once variations in the isotopic data can be related to the physiochemical conditions during metal deposition. This study presents Cu isotope ratios for samples from the Pebble porphyry Cu-Au-Mo deposit in Alaska. The δ65Cu values for hypogene copper sulfides range from -2.09‰ to 1.11‰ and show linear correlations with the δ18O isotope ratios calculated for the fluid in equilibrium with the hydrothermal alteration minerals in each sample. Samples with sodic-potassic, potassic, and illite alteration display a negative linear correlation between the Cu and O isotope results. This suggests that fractionation of Cu isotopes between the fluid and precipitating chalcopyrite is positive as the hydrothermal fluid is evolving from magmatic to mixed magmatic-meteoric compositions. Samples with advanced argillic alteration display a weak positive linear correlation between Cu and O isotope results consistent with small negative fluid-chalcopyrite Cu isotope fractionation during fluid evolution. The hydrothermal fluids that formed sodic-potassic, potassic, and illite alteration likely transported Cu as CuHS0. Hydrothermal fluids that resulted in advanced argillic alteration likely transport Cu as CuCl2-. The pH conditions also control Cu isotope fractionation, consistent with previous experimental work. Larger fractionation factors were found between fluids and chalcopyrite precipitating under neutral conditions contrasting with small fractionation factors calculated between fluids and chalcopyrite precipitating under acidic conditions. Therefore, this study proposes that hydrothermal fluid compositions and pH conditions are related to Cu isotope variations in high temperature magmatic-hydrothermal deposits.

Management of fluid mud in estuaries, bays, and lakes. II: Measurement, modeling, and management

USGS Publications Warehouse

McAnally, W.H.; Teeter, A.; Schoellhamer, David H.; Friedrichs, C.; Hamilton, D.; Hayter, E.; Shrestha, P.; Rodriguez, H.; Sheremet, A.; Kirby, R.

2007-01-01

Techniques for measurement, modeling, and management of fluid mud are available, but research is needed to improve them. Fluid mud can be difficult to detect, measure, or sample, which has led to new instruments and new ways of using existing instruments. Multifrequency acoustic fathometers sense neither density nor viscosity and are, therefore, unreliable in measuring fluid mud. Nuclear density probes, towed sleds, seismic, and drop probes equipped with density meters offer the potential for accurate measurements. Numerical modeling of fluid mud requires solving governing equations for flow velocity, density, pressure, salinity, water surface, plus sediment submodels. A number of such models exist in one-, two-, and three-dimensional form, but they rely on empirical relationships that require substantial site-specific validation to observations. Management of fluid mud techniques can be classified as those that accomplish: Source control, formation control, and removal. Nautical depth, a fourth category, defines the channel bottom as a specific fluid mud density or alternative parameter as safe for navigation. Source control includes watershed management measures to keep fine sediment out of waterways and in-water measures such as structures and traps. Formation control methods include streamlined channels and structures plus other measures to reduce flocculation and structures that train currents. Removal methods include the traditional dredging and transport of dredged material plus agitation that contributes to formation control and/or nautical depth. Conditioning of fluid mud by dredging and aerating offers the possibility of improved navigability. Two examples—the Atchafalaya Bar Channel and Savannah Harbor—illustrate the use of measurements and management of fluid mud.

Hydraulically controlled discrete sampling from open boreholes

USGS Publications Warehouse

Harte, Philip T.

2013-01-01

Groundwater sampling from open boreholes in fractured-rock aquifers is particularly challenging because of mixing and dilution of fluid within the borehole from multiple fractures. This note presents an alternative to traditional sampling in open boreholes with packer assemblies. The alternative system called ZONFLO (zonal flow) is based on hydraulic control of borehole flow conditions. Fluid from discrete fractures zones are hydraulically isolated allowing for the collection of representative samples. In rough-faced open boreholes and formations with less competent rock, hydraulic containment may offer an attractive alternative to physical containment with packers. Preliminary test results indicate a discrete zone can be effectively hydraulically isolated from other zones within a borehole for the purpose of groundwater sampling using this new method.

Diagenetic and compositional controls of wettability in siliceous sedimentary rocks, Monterey Formation, California

NASA Astrophysics Data System (ADS)

Hill, Kristina M.

Modified imbibition tests were performed on 69 subsurface samples from Monterey Formation reservoirs in the San Joaquin Valley to measure wettability variation as a result of composition and silica phase change. Contact angle tests were also performed on 6 chert samples from outcrop and 3 nearly pure mineral samples. Understanding wettability is important because it is a key factor in reservoir fluid distribution and movement, and its significance rises as porosity and permeability decrease and fluid interactions with reservoir grain surface area increase. Although the low permeability siliceous reservoirs of the Monterey Formation are economically important and prolific, a greater understanding of factors that alter their wettability will help better develop them. Imbibition results revealed a strong trend of decreased wettability to oil with increased detrital content in opal-CT phase samples. Opal-A phase samples exhibited less wettability to oil than both opal-CT and quartz phase samples of similar detrital content. Subsurface reservoir samples from 3 oil fields were crushed to eliminate the effect of capillary pressure and cleansed of hydrocarbons to eliminate wettability alterations by asphaltene, then pressed into discs of controlled density. Powder discs were tested for wettability by dispensing a controlled volume of water and motor oil onto the surface and measuring the time required for each fluid to imbibe into the sample. The syringe and software of a CAM101 tensiometer were used to control the amount of fluid dispensed onto each sample, and imbibition completion times were determined by high-speed photography for water drops; oil drop imbibition was significantly slower and imbibition was timed and determined visually. Contact angle of water and oil drops on polished chert and mineral sample surfaces was determined by image analysis and the Young-Laplace equation. Oil imbibition was significantly slower with increased detrital composition and faster with increased silica content in opal-CT and quartz phase samples, implying decreased wettability to oil with increased detrital (clay) content. However, contact angle tests showed that opal-CT is more wetting to oil with increased detritus and results for oil on quartz-phase samples were inconsistent between different proxies for detritus over their very small compositional range. Water contact angle trends also showed inconsistent wetting trends compared to imbibition tests. We believe this is because the small range in bulk detrital composition between the "pure" samples used in contact angle tests was close to analytical error and because small-scale spatial compositional variability may be significant enough to effect wettability. These experiments show that compositional variables significantly affect wettability, outweighing the effect of silica phase.

Characterisation of DOC and its relation to the deep terrestrial biosphere

NASA Astrophysics Data System (ADS)

Vieth, Andrea; Vetter, Alexandra; Sachse, Anke; Horsfield, Brian

2010-05-01

The deep subsurface is populated by a large number of microorganisms playing a pivotal role in the carbon cycling. The question arises as to the origin of the potential carbon sources that support deep microbial communities and their possible interactions within the deep subsurface. As the carbon sources need to be dissolved in formation fluids to become available to microorganisms, the dissolved organic carbon (DOC) needs further characterisation as regards concentration, structural as well as molecular composition and origin. The Malm carbonates in the Molasse basin of southern Germany are of large economic potential as they are targets for both hydrocarbon and geothermal exploration (ANDREWS et al., 1987). Five locations that differ in their depth of the Malm aquifer between 220 m and 3445 m below surface have been selected for fluid sampling. The concentration and the isotopic composition of the DOC have been determined. To get a better insight into the structural composition of the DOC, we also applied size exclusion chromatography and quantified the amount of low molecular weight organic acids (LMWOA) by ion chromatography. With increasing depth of the aquifer the formation fluids show increasing salinity as chloride concentrations increase from 2 to 300 mg/l and also the composition of the DOC changes. Water samples from greater depth (>3000 m) showed that the DOC mainly consists of LMWOA (max. 83 %) and low percentages of neutral compounds (alcohols, aldehyde, ketones, amino acids) as well as "building blocks". Building blocks have been described to be the oxidation intermediates from humic substances to LMWOA. With decreasing depth of the aquifer, the DOC of the fluid becomes increasingly dominated by neutral compounds and the percentage of building blocks increases to around 27%. The fluid sample from 220 m depth still contains a small amount of humic substances. The DOC of formation fluids in some terrestrial sediments may originate from organic-rich layers like coals and source rocks which may provide carbon sources for the deep biosphere by leaching water soluble organic compounds. We investigated the potential of a series of Eocene-Pleistocene coals, mudstones and sandstones from New Zealand with different maturities (Ro between 0.29 and 0.39) and total organic carbon content (TOC) regarding their potential to release such compounds. The water extraction of these New Zealand coals using Soxhlet apparatus resulted in yields of LMWOA that may feed the local deep terrestrial biosphere over geological periods of time (VIETH et al., 2008). However, the DOC of the water extracts mainly consisted of humic substances. To investigate the effect of thermal maturity of the organic matter as well as the effect of the organic matter type on the extraction yields, we examined additional coal samples (Ro between 0.29 and 0.80) and source rock samples from low to medium maturity (Ro between 0.3 to 1.1). Within our presentation we would like to show the compositional diversity and variability of dissolved organic compounds in natural formation fluids as well as in water extracts from a series of very different lithologies and discuss their effects on the carbon cycling in the deep terrestrial subsurface. References: Andrews, J. N., Youngman, M. J., Goldbrunner, J. E., and Darling, W. G., 1987. The geochemistry of formation waters in the Molasse Basin of Upper Austria. Environmental Geology 10, 43-57. Vieth, A., Mangelsdorf, K., Sykes, R., and Horsfield, B., 2008. Water extraction of coals - potential to estimate low molecular weight organic acids as carbon feedstock for the deep terrestrial biosphere? Organic Geochemistry 39, 985-991.

Characterization of Radium and Radon Isotopes in Hydraulic Fracturing Flowback Fluid and Gas from the Marcellus Shale

NASA Astrophysics Data System (ADS)

Bardsley, A.

2015-12-01

High volume hydraulic fracturing of unconventional deposits has expanded rapidly over the past decade in the US, with much attention focused on the Marcellus Shale gas reservoir in the northeastern US. We use naturally occurring radium isotopes and 222Rn to explore changes in formation characteristics as a result of hydraulic fracturing. Gas and produced waters were analyzed from time series samples collected soon after hydraulic fracturing at three Marcellus Shale well sites in the Appalachian Basin, USA. Analyses of δ18O, Cl- , and 226Ra in flowback fluid are consistent with two end member mixing between injected slick water and formation brine. All three tracers indicate that the ratio of injected water to formation brine declines with time across both time series. Cl- concentration (max ~1.5-2.2 M) and 226Ra activity (max ~165-250 Bq/Kg) in flowback fluid are comparable at all three sites. There are differences evident in the stable isotopic composition (δ18O & δD) of injected slick water across the three sites, but all appear to mix with formation brine of similar isotopic composition. On a plot of water isotopes, δ18O in formation brine-dominated fluid is enriched by ~3-4 permille relative to the Global Meteoric Water Line, indicating oxygen exchange with shale. The ratio of 223Ra/226Ra and 228Ra/226Ra in produced waters is quite low relative to shale samples analyzed. This indicates that most of the 226Ra in the formation brine must be sourced from shale weathering or dissolution rather than emanation due to alpha recoil from the rock surface. During the first week of flowback, ratios of short lived isotopes 223Ra and 224Ra to longer lived radium isotopes change modestly, suggesting rock surface area per unit of produced water volume did not change substantially. For one well, longer term gas samples were collected. The 222Rn/methane ratio in produced gas from this site declines with time and may represent a decrease in the brine to gas ratio in the reservoir over the course of six months after initial fracturing. Naturally occurring radium and radon isotopes show promise in elucidating sub-surface dynamics following hydraulic fracturing plays.

Effects of hydraulic frac fluids and formation waters on groundwater microbial communities

NASA Astrophysics Data System (ADS)

Jiménez, Núria; Krüger, Martin

2015-04-01

Shale gas is being considered as a complementary energy resource to other fossil fuels. Its exploitation requires using advanced drilling techniques and hydraulic stimulation (fracking). During fracking operations, large amounts of fluids (fresh water, proppants and chemicals) are injected at high pressures into the formations, to create fractures and fissures, and thus to release gas from the source rock into the wellbore. The injected fluid partly remains in the formation, while up to 40% flows back to the surface, together with reservoir waters, sometimes containing dissolved hydrocarbons, high salt concentrations, etc. The aim of our study was to investigate the potential impacts of frac or geogenic chemicals, frac fluid, formation water or flowback on groudnwater microbial communities. Laboratory experiments under in situ conditions (i.e. at in situ temperatures, with high pressure, etc.) were conducted using groundwater samples from three different locations. Series of microcosms (3 of each kind) containing R2 broth medium or groundwater spiked with either single frac chemicals (including biocides), frac fluids, artificial reservoir water, NaCl, or different mixtures of reservoir water and frac fluid (to simulate flowback) were incubated in the dark. Controls included non-amended and non-inoculated microcosms. Classical microbiological methods and molecular analyses were used to assess changes in the microbial abundance, community structure and function in response to the different treatments. Microbial communities were quite halotolerant and their growth benefited from low concentrations of reservoir waters or salt, but they were negatively affected by higher concentrations of formation waters, salt, biocides, frac fluids or flowback. Changes on the microbial community structure could be detected by T-RFLP. Single frac components like guar gum or choline chloride could be used as substrates, while the effects of others like triethanolamine or light oil distillate hydrogenated depended on the groundwater and could either prevent or have no effect on microbial growth. Ongoing work will provide information on potential transformations of frac or geogenic chemicals by groundwater microbiota and their lifetime.

Effects of hydraulic frac fluids and formation waters on groundwater microbial communities

NASA Astrophysics Data System (ADS)

Krueger, Martin; Jimenez, Nuria

2017-04-01

Shale gas is being considered as a complementary energy resource to other fossil fuels. Its exploitation requires using advanced drilling techniques and hydraulic stimulation (fracking). During fracking operations, large amounts of fluids (fresh water, proppants and chemicals) are injected at high pressures into the formations, to create fractures and fissures, and thus to release gas from the source rock into the wellbore. The injected fluid partly remains in the formation, while up to 40% flows back to the surface, together with reservoir waters, sometimes containing dissolved hydrocarbons, high salt concentrations, etc. The aim of our study was to investigate the potential impacts of frac or geogenic chemicals, frac fluid, formation water or flowback on groudnwater microbial communities. Laboratory experiments under in situ conditions (i.e. at in situ temperature, high pressure) were conducted using groundwater samples from three different locations. Series of microcosms containing R2 broth medium or groundwater spiked with either single frac chemicals (including biocides), frac fluids, artificial reservoir water, NaCl, or different mixtures of reservoir water and frac fluid (to simulate flowback) were incubated in the dark. Controls included non-amended and non-inoculated microcosms. Classical microbiological methods and molecular analyses were used to assess changes in the microbial abundance, community structure and function in response to the different treatments. Microbial communities were quite halotolerant and their growth benefited from low concentrations of reservoir waters or salt, but they were negatively affected by higher concentrations of formation waters, salt, biocides or frac fluids. Changes on the microbial community structure could be detected by T-RFLP. Single frac components like guar gum or choline chloride were used as substrates, while others like triethanolamine or light oil distillate hydrogenated prevented microbial growth in groundwaters. Ongoing work will provide information on potential transformations of frac or geogenic chemicals by groundwater microbiota and their lifetime.

An Investigation Into the Effects of In Vitro Dilution With Different Colloid Resuscitation Fluids on Clot Microstructure Formation.

PubMed

Lawrence, Matthew James; Marsden, Nick; Kaczynski, Jakub; Davies, Gareth; Davies, Nia; Hawkins, Karl; Perumal, Sounder; Brown, Martin Rowan; Morris, Keith; Davidson, Simon J; Williams, Phylip Rhodri; Evans, Phillip Adrian

2016-11-01

Balancing the beneficial effects of resuscitation fluids against their detrimental effect on hemostasis is an important clinical issue. We aim to compare the in vitro effects of 3 different colloid resuscitation fluids (4.5% albumin, hydroxyethyl starch [Voluven 6%], and gelatin [Geloplasma]) on clot microstructure formation using a novel viscoelastic technique, the gel point. This novel hemorheologic technique measures the biophysical properties of the clot and provides an assessment of clot microstructure from its viscoelastic properties. Importantly, in contrast to many assays in routine clinical use, the measurement is performed using unadulterated whole blood in a near-patient setting and provides rapid assessment of coagulation. We hypothesized that different colloids will have a lesser or greater detrimental effect on clot microstructure formation when compared against each other. Healthy volunteers were recruited into the study (n = 104), and a 20-mL sample of whole blood was obtained. Each volunteer was assigned to 1 of the 3 fluids, and the sample was diluted to 1 of 5 different dilutions (baseline, 10%, 20%, 40%, and 60%). The blood was tested using the gel point technique, which measures clot mechanical strength and quantifies clot microstructure (df) at the incipient stages of fibrin formation. df and clot mechanical strength decrease with progressive dilution for all 3 fluids. A significant reduction in df from baseline was recorded at dilutions of 20% for albumin (P < .0001), 40% for starch (P < .0001), and 60% for gelatin (P < .0001). We also observed significant differences, in terms of df, when comparing the different types of colloid (P < .0001). We found that albumin dilution produced the largest changes in clot microstructure, providing the lowest values of df (= 1.41 ± 0.061 at 60% dilution) compared with starch (1.52 ± 0.081) and gelatin (1.58 ± 0.063). We show that dilution with all 3 fluids has a significant effect on coagulation at even relatively low dilution volumes (20% and 40%). Furthermore, we quantify, using a novel viscoelastic technique, how the physiochemical properties of the 3 colloids exert individual changes on clot microstructure.

Long-Term Implanted cOFM Probe Causes Minimal Tissue Reaction in the Brain

PubMed Central

Hochmeister, Sonja; Asslaber, Martin; Kroath, Thomas; Pieber, Thomas R.; Sinner, Frank

2014-01-01

This study investigated the histological tissue reaction to long-term implanted cerebral open flow microperfusion (cOFM) probes in the frontal lobe of the rat brain. Most probe-based cerebral fluid sampling techniques are limited in application time due to the formation of a glial scar that hinders substance exchange between brain tissue and the probe. A glial scar not only functions as a diffusion barrier but also alters metabolism and signaling in extracellular brain fluid. cOFM is a recently developed probe-based technique to continuously sample extracellular brain fluid with an intact blood-brain barrier. After probe implantation, a 2 week healing period is needed for blood-brain barrier reestablishment. Therefore, cOFM probes need to stay in place and functional for at least 15 days after implantation to ensure functionality. Probe design and probe materials are optimized to evoke minimal tissue reaction even after a long implantation period. Qualitative and quantitative histological tissue analysis revealed no continuous glial scar formation around the cOFM probe 30 days after implantation and only a minor tissue reaction regardless of perfusion of the probe. PMID:24621608

Separation of oxalate, formate and glycolate in human body fluid samples by capillary electrophoresis with contactless conductometric detection.

PubMed

Kubáň, Petr; Ďurč, Pavol; Bittová, Miroslava; Foret, František

2014-01-17

A new method for rapid determination of toxic metabolites after methanol and ethylene glycol intoxication - oxalate, formate and glycolate in various body fluid samples (blood serum, saliva, urine, exhaled breath condensate) by capillary electrophoresis with contactless conductometric detection was developed. A selective separation of the three target analytes from other constituents present in the analyzed biological matrices was achieved in less than 6min in a fused silica capillary of 25μm I.D. using an electrolyte comprising 50mM l-histidine and 50mM 2-(N-morpholino)ethanesulfonic acid at pH 6.1. The only sample preparation was dilution with deionized water. The limits of detection were 0.4, 0.6 and 1.3μM and limits of quantitation 1.3, 1.9 and 4.2μM for oxalate, formate and glycolate, respectively. The method provides a simple and rapid diagnostic test in suspected intoxication and is able to distinguish the ingested liquid, based on its metabolite trace. The method presents a fast screening tool that can be applicable in clinical practice. Copyright © 2013 Elsevier B.V. All rights reserved.

Geohydrology of the Stockton Formation and cross-contamination through open boreholes, Hatboro Borough and Warminster Township, Pennsylvania

USGS Publications Warehouse

Sloto, R.A.; Macchiaroli, Paola; Towle, M.T.

1996-01-01

The study area consists of a 9-square-mile area underlain by sedimentary rocks of the middle arkose member of the Stockton Formation of Upper Triassic age. In the Hatboro area, the Stockton Formation strikes approximately N. 65 degrees E. and dps approximately 9 degrees NW. The rocks are chiefly arkosic sandstone and siltstone. Rocks of the Stocton Formation form a complex, heterogeneous, multiaquifer system consisting of a series of gently dipping lithologic units with different hydraulic properties. Most ground water in the unweathered zone moves through a network of interconnecting secondary openigns-fractures, bedding plans, and joints. Ground water is unconfined in the shallower part of the aquifer and semiconfined or confined in the deeper part of the aquifer. Nearly all deep wells in the Stockton Formation are open to several water-bearing zones and are multiaquifer wells. Each water-bearing zone usually has a different hydraulic head. Where differences in hydraulic head exist between water-bearing zones, water in the well bore flows under nonpumping conditions in the direction of decreasing head. Determination of the potential for borehole flow was based on caliper, natural-gamma, single- point-resistance, fluid-resistivity, and (or) fluid-temperature logs that were run in 162 boreholes 31 to 655 feet deep. The direction and rate of borehole-fluid movement were determined in 83 boreholes by the bring-tracing method and in 10 boreholes by use of a heat-pulse flowmeter. Borehole flow was measurable in 65 of the 93 boreholes (70 percent). Fluid movement at rates up to 17 gallons per minute was measured. Downward flow was measured in 36 boreholes, and upward flow was measured in 23 boreholes, not including those boreholes in which two directions of flow were measured. Both upward and downward vertical flow was measured in six boreholes; these boreholes are 396 to 470 feet deep and were among the deepest boreholes logged. Fluid movement was upward in the upper part of the borehole and downward in the lower part of the borehole in two boreholes. Fluid movement wad downward in the upper part of the borehole and upward in the lower part of the borehole in three boreholes. Groung-water contamination by volatile organic compounds (VOC's) is widespread in the study area. Detectable concentrations of VOC's were present in water samples from 24 wells sampled in Hatboro Brough and in water samples for 10 of 14 wells (71 percent) samples in Warminster Township. Samples of borehole flow from nine boreholes in the industrial area of Hatboro were collected for laboratory analysis to estimate the quantity of VOC's in borehole flow. Downward flow was measured in all of these boreholes. Concentrations of TCE, TCA, and 1,1-DCE as great at 5,800, 1,400 and 260 micrograms per liter, respectively, show that some water moving downward in the aquifer through these open boreholes is highly contaminated and that open boreholes may contribute substantially to ground-water contamination. An estimated 14.7 gallons per year of VOC's were moving downward through the nine open boreholes sampled from the contaminated, upper part of the aquifer to the lower part, which is tapped by public supply wells. Borehole geophysical logs were used as a guide to design and construct monitor-well networks at three National Priorities List sites in the area. An open borehole was dirlled, and a suite of geophysical logs was run. Interpretation of geophysical logs enabled the identification of water-bearing zones that produce and receive water; these are zones that should not be connected. From the logs, discrete intervals to be monitored were selected. In the Stockton Formation, the same water-bearing zone may not be intersected in adjacent boreholes, especially if it is a vertical fracture with a diffident magnetic orientation than that of the adjacent boreholes. In most areas of the stockton Formation, depth of water-bearing zones in an are

Diagenetic overprinting of the sphaerosiderite palaeoclimate proxy: are records of pedogenic groundwater δ18O values preserved?

USGS Publications Warehouse

Ufnar, David F.; Gonzalez, Luis A.; Ludvigson, Greg A.; Brenner, Richard L.; Witzkes, Brian J.

2004-01-01

Meteoric sphaerosiderite lines (MSLs), defined by invariant ??18O and variable ??13C values, are obtained from ancient wetland palaeosol sphaerosiderites (millimetre-scale FeCO3 nodules), and are a stable isotope proxy record of terrestrial meteoric isotopic compositions. The palaeoclimatic utility of sphaerosiderite has been well tested; however, diagenetically altered horizons that do not yield simple MSLs have been encountered. Well-preserved sphaerosiderites typically exhibit smooth exteriors, spherulitic crystalline microstructures and relatively pure (> 95 mol% FeCO3) compositions. Diagenetically altered sphaerosiderites typically exhibit corroded margins, replacement textures and increased crystal lattice substitution of Ca2+, Mg2+ and Mn2+ for Fe2+. Examples of diagenetically altered Cretaceous sphaerosiderite-bearing palaeosols from the Dakota Formation (Kansas), the Swan River Formation (Saskatchewan) and the Success S2 Formation (Saskatchewan) were examined in this study to determine the extent to which original, early diagenetic ??18O and ??13C values are preserved. All three units contain poikilotopic calcite cements with significantly different ??18O and ??13C values from the co-occurring sphaerosiderites. The complete isolation of all carbonate phases is necessary to ensure that inadvertent physical mixing does not affect the isotopic analyses. The Dakota and Swan River samples ultimately yield distinct MSLs for the sphaerosiderites, and MCLs (meteoric calcite lines) for the calcite cements. The Success S2 sample yields a covariant ??18O vs. ??13C trend resulting from precipitation in pore fluids that were mixtures between meteoric and modified marine phreatic waters. The calcite cements in the Success S2 Formation yield meteoric ??18O and ??13C values. A stable isotope mass balance model was used to produce hyperbolic fluid mixing trends between meteoric and modified marine end-member compositions. Modelled hyperbolic fluid mixing curves for the Success S2 Formation suggest precipitation from fluids that were < 25% sea water. ?? 2004 International Association of Sedimentologists.

The Green River natural analogue as a field laboratory to study the long-term fate of CO2 in the subsurface

NASA Astrophysics Data System (ADS)

Busch, Andreas; Kampman, Niko; Hangx, Suzanne; Bertier, Pieter; Bickle, Mike; Harrington, Jon

2015-04-01

Understanding the long-term response of CO2 injected into porous reservoirs is one of the most important aspects to demonstrate safe and permanent storage. At the same time this is one of the least understood aspects of CCS in general. The reasons are that 'long-term', in the sense of hundreds to thousands of years, is impractical from a laboratory and rather idealised from a reservoir modelling perspective. However understanding the coupled long-term hydro-chemical-mechanical response of a reservoir-seal pair following CO2 injection is highly desirable to improve confidence and trust from a regulator and societal perspective, as well as to improve risk assessment and risk reduction. In order to provide one building block to advance understanding of this subject, in July 2012 Shell recovered some 300m of core from a scientific drill hole through a natural CO2 field near Green River, Utah. This core transected two sandstone formations (Entrada and Navajo) and one intervening seal layer, composed of interbedded marine clay-/silt and sandstones (Carmel Fm.). Fluid samples and core material were taken adjacent to the Little Grand Wash Fault (LGW), along which CO2-charged fluids traverse from depth to the surface and which is believed to be the migration pathway for CO2 inflow into the reservoirs. In-situ pH, CO2 concentrations, and fluid element and isotope geochemistry were determined from wireline downhole sampling of pressurized fluids taken from the Navajo reservoirs. The fluid geochemistry provides important constraints on reservoir filling by flow of CO2 -charged brines through the LGW fault damage zone, macro-scale fluid flow in the reservoirs and the state of fluid-mineral thermodynamic disequilibrium, from which the nature of the fluid-mineral reactions can be interpreted. In addition to core samples, we obtained control samples from stratigraphically equivalent outcrop locations and drill holes that were not subject to alterations by CO2 -charged fluids and served as a direct comparison to the altered samples. We obtained geomechanical, mineralogical, geochemical and petrophysical laboratory data along the entire length of the core and from the control samples. Furthermore, we performed more detailed studies through portions of the caprock in direct contact with the CO2-charged reservoirs. This was done to constrain the nature and penetration depths of the CO2-promoted fluid-mineral reaction fronts. These reactions have taken place in the last ~100,000 years, which has been set as an upper limit for the onset of CO2 influx into the formations. This data has been used as input for reactive (transport) modeling. In addition, we compared geomechanical data from the CO2 -exposed core and the unreacted control samples to assess the mechanical stability of reservoir and seal rocks in a CO2 storage complex following mineral dissolution and precipitation for thousands of years.

Similarities and Differences in the Distributions of Hydrothermal Venting and the Formation of Seafloor Massive Sulfide Deposits at the Tui Malila and Mariner Vent Fields, Valu Fa Ridge

NASA Astrophysics Data System (ADS)

Tivey, M. K.; Evans, G. N.; Ferrini, V. L.; Spierer, H.

2016-12-01

High-resolution bathymetric mapping and recovery and study of samples from precisely known locations relative to local tectonic and volcanic features provide insight into the formation of seafloor massive sulfide deposits. Additional insight comes from repeat mapping efforts in 2005 and 2016 that provide details of relations and changes that may have occurred over time. Located 21 km apart on the Valu Fa Ridge, the Tui Malila and Mariner vent fields exhibit contrasting vent fluid chemistry, mineral deposit composition, deposit morphology, and seafloor morphology. At the Tui Malila vent field, near-neutral pH fluids with low metal contents vent from Zn- and Ba-rich, but Cu-poor deposits. The highest temperature fluids are found near the intersection of two faults and between volcanic domes. In contrast, acidic, metal-rich hydrothermal fluids at the Mariner vent field vent from Cu-rich, Zn-poor deposits. No discernable faults are present. At both the Tui Malila and Mariner vent fields, intermediate temperature fluids were sampled emanating from barite-rich deposits. At the Tui Malila vent field, intermediate fluids vent from flange-dominated edifices that are located on brecciated lava flow that overlays one of the two faults. Intermediate fluids at the Mariner vent field vent from squat terrace-like edifices located peripheral (10-15 m) to high-temperature chimney edifices, and seafloor morphology is dominated by brecciated lava flows. Thermodynamic models of mixing between high-temperature hydrothermal fluids and seawater that consider subsurface deposition of sulfide minerals and iron oxyhydroxide were used to reproduce the chemistry of intermediate fluids. This study suggests that the porous, brecciated lavas characteristic of these two vent fields provide sites for subsurface mixing and contribute to mineral deposition, with the faults at the Tui Malila vent field providing a pathway for subsurface fluid flow.

Element mobilization from Bakken shales as a function of water chemistry.

PubMed

Wang, Lin; Burns, Scott; Giammar, Daniel E; Fortner, John D

2016-04-01

Waters that return to the surface after injection of a hydraulic fracturing fluid for gas and oil production contain elements, including regulated metals and metalloids, which are mobilized through interactions between the fracturing fluid and the shale formation. The rate and extent of mobilization depends on the geochemistry of the formation and the chemical characteristics of the fracturing fluid. In this work, laboratory scale experiments investigated the influence of water chemistry on element mobilization from core samples taken from the Bakken formation, one of the most productive shale oil plays in the US. Fluid properties were systematically varied and evaluated with regard to pH, oxidant level, solid:water ratio, temperature, and chemical additives. Element mobilization strongly depended on solution pH and redox conditions and to a lesser extent on the temperature and solid:water ratio. The presence of oxygen and addition of hydrogen peroxide or ammonium persulfate led to pyrite oxidation, resulting in elevated sulfate concentrations. Further, depending on the mineral carbonates available to buffer the system pH, pyrite oxidation could lower the system pH and enhance the mobility of several metals and metalloids. Copyright © 2016 Elsevier Ltd. All rights reserved.

Solution mining and heating by oxidation for treating hydrocarbon containing formations

DOEpatents

Vinegar, Harold J.; Stegemeier, George Leo

2009-06-23

A method for treating an oil shale formation comprising nahcolite includes providing a first fluid to a portion of the formation. A second fluid is produced from the portion. The second fluid includes at least some nahcolite dissolved in the first fluid. A controlled amount of oxidant is provided to the portion of the formation. Hydrocarbon fluids are produced from the formation.

Solution mining systems and methods for treating hydrocarbon containing formations

DOEpatents

Vinegar, Harold J [Bellaire, TX; de Rouffignac, Eric Pierre [Rijswijk, NL; Schoeling, Lanny Gene [Katy, TX

2009-07-14

A method for treating an oil shale formation comprising nahcolite is disclosed. The method includes providing a first fluid to a portion of the formation through at least two injection wells. A second fluid is produced from the portion through at least one injection well until at least two injection wells are interconnected such that fluid can flow between the two injection wells. The second fluid includes at least some nahcolite dissolved in the first fluid. The first fluid is injected through one of the interconnected injection wells. The second fluid is produced from at least one of the interconnected injection wells. Heat is provided from one or more heaters to the formation to heat the formation. Hydrocarbon fluids are produced from the formation.

Re-injection feasibility study of fracturing flow-back fluid in shale gas mining

NASA Astrophysics Data System (ADS)

Kang, Dingyu; Xue, Chen; Chen, Xinjian; Du, Jiajia; Shi, Shengwei; Qu, Chengtun; Yu, Tao

2018-02-01

Fracturing flow-back fluid in shale gas mining is usually treated by re-injecting into formation. After treatment, the fracturing flow-back fluid is injected back into the formation. In order to ensure that it will not cause too much damage to the bottom layer, feasibility evaluations of re-injection of two kinds of fracturing fluid with different salinity were researched. The experimental research of the compatibility of mixed water samples based on the static simulation method was conducted. Through the analysis of ion concentration, the amount of scale buildup and clay swelling rate, the feasibility of re-injection of different fracturing fluid were studied. The result shows that the swelling of the clay expansion rate of treated fracturing fluid is lower than the mixed water of treated fracturing fluid and the distilled water, indicating that in terms of clay expansion rate, the treated fracturing flow-back fluid is better than that of water injection after re-injection. In the compatibility test, the maximum amount of fouling in the Yangzhou oilfield is 12mg/L, and the maximum value of calcium loss rate is 1.47%, indicating that the compatibility is good. For the fracturing fluid with high salinity in the Yanchang oilfield, the maximum amount of scaling is 72mg/L, and the maximum calcium loss rate is 3.50%, indicating that the compatibility is better.

Measuring temporal variability in pore-fluid chemistry to assess gas hydrate stability: development of a continuous pore-fluid array.

PubMed

Lapham, Laura L; Chanton, Jeffrey P; Martens, Christopher S; Higley, Paul D; Jannasch, Hans W; Woolsey, J Robert

2008-10-01

A specialized pore-fluid array (PFA) sampler was designed to collect and store pore fluids to monitor temporal changes of ions and gases in gas hydrate bearing sediments. We tested the hypothesis that pore-fluid chemistry records hydrate formation or decomposition events and reflects local seismic activity. The PFA is a seafloor probe that consists of an interchangeable instrument package that houses OsmoSamplers, long-term pore-fluid samplers, a specialized low-dead volume fluid coupler, and eight sample ports along a 10 m sediment probe shaft. The PFA was deployed at Mississippi Canyon 118, a Gulf of Mexico hydrate site. A 170 day record was acquired from the overlying water and 1.3 m below seafloor (mbsf). Fluids were measured for dissolved chloride, sulfate, and methane concentrations and dissolved inorganic carbon and methane stable carbon and deuterium isotope ratios. Chloride and sulfate did not change significantly over time, suggesting the absence of gas hydrate formation or decomposition events. Over the temporal record, methane concentrations averaged 4 mM at 1.3 mbsf, and methane was thermogenic in origin (delta13C-CH4 = -32.4 +/- 3.4 per thousand). The timing of an anomalous 14 mM methane spike coincided with a nearby earthquake (Mw = 5.8), consistent with the hypothesis that pore-fluid chemistry reflects seismic events.

Stimuli Responsive/Rheoreversible Hydraulic Fracturing Fluids for Enhanced Geothermal Energy Production (Part II)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bonneville, Alain; Jung, Hun Bok; Shao, Hongbo

We have used an environmentally friendly and recyclable hydraulic fracturing fluid - diluted aqueous solutions of polyallylamine or PAA – for reservoir stimulation in Enhanced Geothermal System (EGS). This fluid undergoes a controlled and large volume expansion with a simultaneous increase in viscosity triggered by CO2 at EGS temperatures. We are presenting here the results of laboratory-scale hydraulic fracturing experiment using the fluid on small cylindrical rock cores (1.59 cm in diameter and 5.08 cm in length) from the Coso geothermal field in California. Rock samples consisted of Mesozoic diorite metamorphosed to greenschist facies. The experiments were conducted on 5more » samples for realistic ranges of pressures (up to 275 bar) and temperatures (up to 210 °C) for both the rock samples and the injected fluid. After fracturing, cores were subjected to a CO2 leakage test, injection of KI solution, and X-ray microtomography (XMT) scanning to examine the formation and distribution of fractures. The design and conduct of these experiments will be presented and discussed in details. Based on the obtained XMT images, Computational Fluid Dynamics (CFD) simulations were then performed to visualize hydraulic fractures and compute the bulk permeability. OpenFOAM (OpenCFD Ltd., Reading, UK), was used to solve the steady state simulation. The flow predictions, based upon the laminar, 3-D, incompressible Navier-Stokes equations for fluid mass and momentum, show the remarkable stimulation of the permeability in the core samples and demonstrate the efficiency of such a CO2 triggered fluid in EGS.« less

Aquifers survey in the context of source rocks exploitation: from baseline acquisition to long term monitoring

NASA Astrophysics Data System (ADS)

Garcia, Bruno; Rouchon, Virgile; Deflandre, Jean-Pierre

2017-04-01

Producing hydrocarbons from source rocks (like shales: a mix of clays, silts, carbonate and sandstone minerals containing matured organic matter, i.e. kerogen oil and gas, but also non-hydrocarbon various species of chemical elements including sometimes radioactive elements) requires to create permeability within the rock matrix by at least hydraulically fracturing the source rock. It corresponds to the production of hydrocarbon fuels that have not been naturally expelled from the pressurized matured source rock and that remain trapped in the porosity or/and kerogen porosity of the impermeable matrix. Azimuth and extent of developed fractures can be respectively determined and mapped by monitoring the associated induced microseismicity. This allows to have an idea of where and how far injected fluids penetrated the rock formation. In a geological context, aquifers are always present in the vicinity -or on fluid migration paths- of such shale formations: deep aquifers (near the shale formation) up to sub-surface and potable (surface) aquifers. Our purpose will be to track any unsuitable invasion or migration of chemicals specifies coming from matured shales of production fluids including both drilling and fracturing ones into aquifers. Our objective is to early detect and alarm of any anomaly to avoid any important environmental issue. The approach consists in deploying a specific sampling tool within a well to recover formation fluids and to run a panoply of appropriate laboratory tests to state on fluid characteristics. Of course for deep aquifers, such a characterization process may consider aquifer properties prior producing shale oil and gas, as they may contain naturally some chemical species present in the source rocks. One can also consider that a baseline acquisition could be justified in case of possible previous invasion of non-natural fluids in the formation under survey (due to any anthropogenic action at surface or in the underground). The paper aims at presenting the protocol and routine test we propose to make our early detection approach efficient for production of shale hydrocarbon fluids, in considering the source-rock reservoir itself, the aquifers, and also the chemical species present in the fluids that are used for hydraulic fracturing operations.

Identification of sandstone core damage using scanning electron microscopy

NASA Astrophysics Data System (ADS)

Ismail, Abdul Razak; Jaafar, Mohd Zaidi; Sulaiman, Wan Rosli Wan; Ismail, Issham; Shiunn, Ng Yinn

2017-12-01

Particles and fluids invasion into the pore spaces causes serious damage to the formation, resulting reduction in petroleum production. In order to prevent permeability damage for a well effectively, the damage mechanisms should be identified. In this study, water-based drilling fluid was compared to oil-based drilling fluids based on microscopic observation. The cores were damaged by several drilling fluid systems. Scanning electron microscope (SEM) was used to observe the damage mechanism caused by the drilling fluids. Results showed that the ester based drilling fluid system caused the most serious damage followed by synthetic oil based system and KCI-polymer system. Fine solids and filtrate migration and emulsion blockage are believed to be the major mechanisms controlling the changes in flow properties for the sandstone samples.

Design criteria for developing low-resource magnetic bead assays using surface tension valves

PubMed Central

Adams, Nicholas M.; Creecy, Amy E.; Majors, Catherine E.; Wariso, Bathsheba A.; Short, Philip A.; Wright, David W.; Haselton, Frederick R.

2013-01-01

Many assays for biological sample processing and diagnostics are not suitable for use in settings that lack laboratory resources. We have recently described a simple, self-contained format based on magnetic beads for extracting infectious disease biomarkers from complex biological samples, which significantly reduces the time, expertise, and infrastructure required. This self-contained format has the potential to facilitate the application of other laboratory-based sample processing assays in low-resource settings. The technology is enabled by immiscible fluid barriers, or surface tension valves, which stably separate adjacent processing solutions within millimeter-diameter tubing and simultaneously permit the transit of magnetic beads across the interfaces. In this report, we identify the physical parameters of the materials that maximize fluid stability and bead transport and minimize solution carryover. We found that fluid stability is maximized with ≤0.8 mm i.d. tubing, valve fluids of similar density to the adjacent solutions, and tubing with ≤20 dyn/cm surface energy. Maximizing bead transport was achieved using ≥2.4 mm i.d. tubing, mineral oil valve fluid, and a mass of 1-3 mg beads. The amount of solution carryover across a surface tension valve was minimized using ≤0.2 mg of beads, tubing with ≤20 dyn/cm surface energy, and air separators. The most favorable parameter space for valve stability and bead transport was identified by combining our experimental results into a single plot using two dimensionless numbers. A strategy is presented for developing additional self-contained assays based on magnetic beads and surface tension valves for low-resource diagnostic applications. PMID:24403996

Trace and minor element variations and sulfur isotopes in crystalline and colloform ZnS: Incorporation mechanisms and implications for their genesis

USGS Publications Warehouse

Pfaff, Katharina; Koenig, Alan; Wenzel, Thomas; Ridley, Ian; Hildebrandt, Ludwig H.; Leach, David L.; Markl, Gregor

2011-01-01

Various models have been proposed to explain the formation mechanism of colloform sphalerite, but the origin is still under debate. In order to decipher influences on trace element incorporation and sulfur isotope composition, crystalline and colloform sphalerite from the carbonate-hosted Mississippi-Valley Type (MVT) deposit near Wiesloch, SW Germany, were investigated and compared to sphalerite samples from 52 hydrothermal vein-type deposits in the Schwarzwald ore district, SW Germany to study the influence of different host rocks, formation mechanisms and fluid origin on trace element incorporation. Trace and minor element incorporation in sphalerite shows some correlation to their host rock and/or origin of fluid, gangue, paragenetic minerals and precipitation mechanisms (e.g., diagenetic processes, fluid cooling or fluid mixing). Furthermore, crystalline sphalerite is generally enriched in elements like Cd, Cu, Sb and Ag compared to colloform sphalerite that mainly incorporates elements like As, Pb and Tl. In addition, sulfur isotopes are characterized by positive values for crystalline and strongly negative values for colloform sphalerite. The combination of trace element contents, typical minerals associated with colloform sphalerite from Wiesloch, sulfur isotopes and thermodynamic considerations helped to evaluate the involvement of sulfate-reducing bacteria in water-filled karst cavities. Sulfate-reducing bacteria cause a sulfide-rich environment that leads in case of a metal-rich fluid supply to a sudden oversaturation of the fluid with respect to galena, sphalerite and pyrite. This, however, exactly coincides with the observed crystallization sequence of samples involving colloform sphalerite from the Wiesloch MVT deposit.

Influence of mixing conditions on the rheological properties and structure of capillary suspensions

PubMed Central

Bossler, Frank; Weyrauch, Lydia; Schmidt, Robert; Koos, Erin

2017-01-01

The rheological properties of a suspension can be dramatically altered by adding a small amount of a secondary fluid that is immiscible with the bulk liquid. These capillary suspensions exist either in the pendular state where the secondary fluid preferentially wets the particles or the capillary state where the bulk fluid is preferentially wetting. The yield stress, as well as storage and loss moduli, depends on the size and distribution of secondary phase droplets created during sample preparation. Enhanced droplet breakup leads to stronger sample structures. In capillary state systems, this can be achieved by increasing the mixing speed and time of turbulent mixing using a dissolver stirrer. In the pendular state, increased mixing speed also leads to better droplet breakup, but spherical agglomeration is favored at longer times decreasing the yield stress. Additional mixing with a ball mill is shown to be beneficial to sample strength. The influence of viscosity variance between the bulk and second fluid on the droplet breakup is excluded by performing experiments with viscosity-matched fluids. These experiments show that the capillary state competes with the formation of Pickering emulsion droplets and is often more difficult to achieve than the pendular state. PMID:28194044

Studying physical properties of deformed intact and fractured rocks by micro-scale hydro-mechanical-seismicity model

NASA Astrophysics Data System (ADS)

Raziperchikolaee, Samin

The pore pressure variation in an underground formation during hydraulic stimulation of low permeability formations or CO2 sequestration into saline aquifers can induce microseismicity due to fracture generation or pre-existing fracture activation. While the analysis of microseismic data mainly focuses on mapping the location of fractures, the seismic waves generated by the microseismic events also contain information for understanding of fracture mechanisms based on microseismic source analysis. We developed a micro-scale geomechanics, fluid-flow and seismic model that can predict transport and seismic source behavior during rock failure. This model features the incorporation of microseismic source analysis in fractured and intact rock transport properties during possible rock damage and failure. The modeling method considers comprehensive grains and cements interaction through a bonded-particle-model. As a result of grain deformation and microcrack development in the rock sample, forces and displacements in the grains involved in the bond breakage are measured to determine seismic moment tensor. In addition, geometric description of the complex pore structure is regenerated to predict fluid flow behavior of fractured samples. Numerical experiments are conducted for different intact and fractured digital rock samples, representing various mechanical behaviors of rocks and fracture surface properties, to consider their roles on seismic and transport properties of rocks during deformation. Studying rock deformation in detail provides an opportunity to understand the relationship between source mechanism of microseismic events and transport properties of damaged rocks to have a better characterizing of fluid flow behavior in subsurface formations.

Understanding the interaction of injected CO2 and reservoir fluids in the Cranfield enhanced oil recovery (EOR) field (MS, USA) by non-radiogenic noble gas isotopes

NASA Astrophysics Data System (ADS)

Gyore, Domokos; Stuart, Finlay; Gilfillan, Stuart

2016-04-01

Identifying the mechanism by which the injected CO2 is stored in underground reservoirs is a key challenge for carbon sequestration. Developing tracing tools that are universally deployable will increase confidence that CO2 remains safely stored. CO2 has been injected into the Cranfield enhanced oil recovery (EOR) field (MS, USA) since 2008 and significant amount of CO2 has remained (stored) in the reservoir. Noble gases (He, Ne, Ar, Kr, Xe) are present as minor natural components in the injected CO2. He, Ne and Ar previously have been shown to be powerful tracers of the CO2 injected in the field (Györe et al., 2015). It also has been implied that interaction with the formation water might have been responsible for the observed CO2 loss. Here we will present work, which examines the role of reservoir fluids as a CO2 sink by examining non-radiogenic noble gas isotopes (20Ne, 36Ar, 84Kr, 132Xe). Gas samples from injection and production wells were taken 18 and 45 months after the start of injection. We will show that the fractionation of noble gases relative to Ar is consistent with the different degrees of CO2 - fluid interaction in the individual samples. The early injection samples indicate that the CO2 injected is in contact with the formation water. The spatial distribution of the data reveal significant heterogeneity in the reservoir with some wells exhibiting a relatively free flow path, where little formation water is contacted. Significantly, in the samples, where CO2 loss has been previously identified show active and ongoing contact. Data from the later stage of the injection shows that the CO2 - oil interaction has became more important than the CO2 - formation water interaction in controlling the noble gas fingerprint. This potentially provides a means to estimate the oil displacement efficiency. This dataset is a demonstration that noble gases can resolve CO2 storage mechanisms and its interaction with the reservoir fluids with high resolution. References: Györe, D., Stuart, F.M., Gilfillan, S.M.V., Waldron, S., 2015. Tracing injected CO2 in the Cranfield enhanced oil recovery field (MS, USA) using He, Ne and Ar isotopes. Int. J. Greenh. Gas Con. 42, 554-561.

Fast fluid-flow events within a subduction-related vein system in oceanic eclogite: implications for pore fluid pressure at the plate interface

NASA Astrophysics Data System (ADS)

Taetz, Stephan; John, Timm; Bröcker, Michael; Spandler, Carl; Stracke, Andreas

2017-04-01

A better understanding of the subduction zone fluid cycle and its mechanical feedback requires in-depth knowledge of how fluids flow within and out of the descending slabs. In order to develop reliable quantitative models of fluid flow, the general relationship between dehydration reactions, fluid pathway formation, and the dimensions and timescales of distinct fluid flow events have to be explored. The high-pressure/low-temperature metamorphic rocks of the Pouébo Eclogite Mélange in New Caledonia provide an excellent opportunity to study the fluid flux in a subduction zone setting. Fluid dynamics are recorded by high-pressure veins that cross-cut eclogite facies mélange blocks from this occurrence. Two types of garnet-quartz-phengite veins can be distinguished. These veins record both synmetamorphic internal fluid release by mineral breakdown reactions (type I veins) as well as infiltration of an external fluid (type II veins) and the associated formation of a reaction halo. The overall dehydration, fluid accumulation and fluid migration documented by the type I veins occurred on a timescale of 10^5-106 years that is mainly given by the geometry and convergence rate of the subduction system. In order to quantify the timeframe of fluid-rock interaction between the external fluid and the wall-rock, we have applied Li-isotope chronology. A continuous profile was sampled perpendicular to a type II vein including material from the vein, the reaction selvage and the immediate host rock. Additional drill cores were taken from parts of the outcrop that most likely remained completely unaffected by fluid infiltration-induced alteration. Different Li concentrations in the internal and external fluid reservoirs produced a distinct diffusion profile of decreasing Li concentration and increasing δ7Li as the reaction front propagated into the host-rock. Li-chronometric constraints indicate that fluid-rock interaction related to the formation of the type II veins and had been completed within ca. 3 years. The short-lived, pulse-like character of this process is in accordance with the notion that fluid flow related to oceanic crust dehydration at the blueschist-to-eclogite transition contributes to or even dominates episodic pore fluid pressure increases at the plate interface which may trigger slip events reported from many subduction zones.

The U-tube: A novel system for acquiring borehole fluid samples from a deep geologic CO2 sequestration experiment

USGS Publications Warehouse

Freifeild, Barry M.; Trautz, Robert C.; Kharaka, Yousif K.; Phelps, Tommy J.; Myer, Larry R.; Hovorka, Susan D.; Collins, Daniel J.

2005-01-01

A novel system has been deployed to obtain geochemical samples of water and gas, at in situ pressure, during a geologic CO2 sequestration experiment conducted in the Frio brine aquifer in Liberty County, Texas. Project goals required high-frequency recovery of representative and uncontaminated aliquots of a rapidly changing two-phase fluid (supercritical CO2 and brine) fluid from 1.5 km depth. The data sets collected, using both the liquid and gas portions of the downhole samples, provide insights into the coupled hydrogeochemical issues affecting CO2sequestration in brine-filled formations. While the basic premise underlying the U-tube sampler is not new, the system is unique because careful consideration was given to the processing of the recovered two-phase fluids. In particular, strain gauges mounted beneath the high-pressure surface sample cylinders measured the ratio of recovered brine to supercritical CO2. A quadrupole mass spectrometer provided real-time gas analysis for perfluorocarbon and noble gas tracers that were injected along with the CO2. The U-tube successfully acquired frequent samples, facilitating accurate delineation of the arrival of the CO2 plume, and on-site analysis revealed rapid changes in geochemical conditions.

The U-tube: A novel system for acquiring borehole fluid samples from a deep geologic CO2 sequestration experiment

USGS Publications Warehouse

Freifeild, Barry M.; Trautz, Robert C.; Kharaka, Yousif K.; Phelps, Tommy J.; Myer, Larry R.; Hovorka, Susan D.; Collins, Daniel J.

2005-01-01

A novel system has been deployed to obtain geochemical samples of water and gas, at in situ pressure, during a geologic CO2 sequestration experiment conducted in the Frio brine aquifer in Liberty County, Texas. Project goals required high-frequency recovery of representative and uncontaminated aliquots of a rapidly changing two-phase fluid (supercritical CO2 and brine) fluid from 1.5 km depth. The data sets collected, using both the liquid and gas portions of the downhole samples, provide insights into the coupled hydrogeochemical issues affecting CO2 sequestration in brine-filled formations. While the basic premise underlying the U-tube sampler is not new, the system is unique because careful consideration was given to the processing of the recovered two-phase fluids. In particular, strain gauges mounted beneath the high-pressure surface sample cylinders measured the ratio of recovered brine to supercritical CO2. A quadrupole mass spectrometer provided real-time gas analysis for perfluorocarbon and noble gas tracers that were injected along with the CO2. The U-tube successfully acquired frequent samples, facilitating accurate delineation of the arrival of the CO2 plume, and on-site analysis revealed rapid changes in geochemical conditions.

The U-tube: A novel system for acquiring borehole fluid samples from a deep geologic CO2 sequestration experiment

NASA Astrophysics Data System (ADS)

Freifeld, Barry M.; Trautz, Robert C.; Kharaka, Yousif K.; Phelps, Tommy J.; Myer, Larry R.; Hovorka, Susan D.; Collins, Daniel J.

2005-10-01

A novel system has been deployed to obtain geochemical samples of water and gas, at in situ pressure, during a geologic CO2 sequestration experiment conducted in the Frio brine aquifer in Liberty County, Texas. Project goals required high-frequency recovery of representative and uncontaminated aliquots of a rapidly changing two-phase fluid (supercritical CO2 and brine) fluid from 1.5 km depth. The data sets collected, using both the liquid and gas portions of the downhole samples, provide insights into the coupled hydrogeochemical issues affecting CO2 sequestration in brine-filled formations. While the basic premise underlying the U-tube sampler is not new, the system is unique because careful consideration was given to the processing of the recovered two-phase fluids. In particular, strain gauges mounted beneath the high-pressure surface sample cylinders measured the ratio of recovered brine to supercritical CO2. A quadrupole mass spectrometer provided real-time gas analysis for perfluorocarbon and noble gas tracers that were injected along with the CO2. The U-tube successfully acquired frequent samples, facilitating accurate delineation of the arrival of the CO2 plume, and on-site analysis revealed rapid changes in geochemical conditions.

Improved Characterization and Modeling of Tight Oil Formations for CO 2 Enhanced Oil Recovery Potential and Storage Capacity Estimation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sorensen, James; Smith, Steven; Kurz, Bethany

Tight oil formations such as those in the Bakken petroleum system are known to hold hundreds of billions of barrels of oil in place; however, the primary recovery factor for these plays is typically less than 10%. Tight oil formations, including the Bakken Formation, therefore, may be attractive candidates for enhanced oil recovery (EOR) using CO 2. Multiphase fluid behavior and flow in fluid-rich shales can vary substantially depending on the size of pore throats, and properties such as fluid viscosity and density are much different in nanoscale pores than in macroscale pores. Thus it is critical to understand themore » nature and distribution of nano-, micro-, and macroscale pores and fracture networks. To address these issues, the Energy & Environmental Research Center (EERC) has been conducting a research program entitled “Improved Characterization and Modeling of Tight Oil Formations for CO 2 Enhanced Oil Recovery Potential and Storage Capacity Estimation.” The objectives of the project are 1) the use of advanced characterization methods to better understand and quantify the petrophysical and geomechanical factors that control CO 2 and oil mobility within tight oil formation samples, 2) the determination of CO 2 permeation and oil extraction rates in tight reservoir rocks and organic-rich shales of the Bakken, and 3) the integration of the laboratory-based CO 2 permeation and oil extraction data and the characterization data into geologic models and dynamic simulations to develop predictions of CO 2 storage resource and EOR in the Bakken tight oil formation. A combination of standard and advanced petrophysical characterization techniques were applied to characterize samples of Bakken Formation tight reservoir rock and shales from multiple wells. Techniques included advanced computer tomography (CT) imaging, scanning electron microscopy (SEM) techniques, whole-core and micro x-ray CT imaging, field emission (FE) SEM, and focused ion beam (FIB) SEM. Selected samples were also analyzed for geomechanical properties. X-ray CT imaging yielded information on the occurrence of fractures, bedding planes, fossils, and bioturbation in core, as well as data on bulk density and photoelectric factor logs, which were used to interpret porosity, organic content, and mineralogy. FESEM was used for characterization of nano- and microscale features, including nanoscale pore visualization and micropore and pore throat mineralogy. FIBSEM yielded micro- to nanoscale visualization of fracture networks, porosity and pore-size distribution, connected versus isolated porosity, and distribution of organics. Results from the characterization activities provide insight on nanoscale fracture properties, pore throat mineralogy and connectivity, rock matrix characteristics, mineralogy, and organic content. Laboratory experiments demonstrated that CO 2 can permeate the tight matrix of Bakken shale and nonshale reservoir samples and mobilize oil from those samples. Geologic models were created at scales ranging from the core plug to the reservoir, and dynamic simulations were conducted. The data from the characterization and laboratory-based activities were integrated into modeling research activities to determine the fundamental mechanisms controlling fluid transport in the Bakken, which support EOR scheme design and estimation of CO 2 storage potential in tight oil formations. Simulation results suggest a CO 2 storage resource estimate range of 169 million to 1.5 billion tonnes for the Bakken in North Dakota, possibly resulting in 1.8 billion to 16 billion barrels of incremental oil.« less

Development of a novel method for amniotic fluid stem cell storage.

PubMed

Zavatti, Manuela; Beretti, Francesca; Casciaro, Francesca; Comitini, Giuseppina; Franchi, Fabrizia; Barbieri, Veronica; Bertoni, Laura; De Pol, Anto; La Sala, Giovanni B; Maraldi, Tullia

2017-08-01

Current procedures for collection of human amniotic fluid stem cells (hAFSCs) indicate that cells cultured in a flask for 2 weeks can then be used for research. However, hAFSCs can be retrieved directly from a small amount of amniotic fluid that can be obtained at the time of diagnostic amniocentesis. The aim of this study was to determine whether direct freezing of amniotic fluid cells is able to maintain or improve the potential of a sub-population of stem cells. We compared the potential of the hAFSCs regarding timing of freezing, cells obtained directly from amniotic fluid aspiration (D samples) and cells cultured in a flask before freezing (C samples). Colony-forming-unit ability, proliferation, morphology, stemness-related marker expression, senescence, apoptosis and differentiation potential of C and D samples were compared. hAFSCs isolated from D samples expressed mesenchymal stem cells markers until later passages, had a good proliferation rate and exhibited differentiation capacity similar to hAFSCs of C samples. Interestingly, direct freezing induced a higher concentration of cells positive for pluripotency stem cell markers, without teratoma formation in vivo. This study suggests that minimal processing may be adequate for the banking of amniotic fluid cells, avoiding in vitro passages before the storage and exposure to high oxygen concentration, which affect stem cell properties. This technique might be a cost-effective and reasonable approach to the process of Good Manufacturing Process accreditation for stem-cell banks. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Effects of Hydraulic Frac Fluids on Subsurface Microbial Communities in Gas Shales

NASA Astrophysics Data System (ADS)

Jiménez, Núria; Krüger, Martin

2014-05-01

Shale gas is being considered as a complementary energy resource to coal or other fossil fuels. The exploitation of unconventional gas reservoirs requires the use of advanced drilling techniques and hydraulic stimulation (fracking). During fracking operations, large amounts of fluids (fresh water, proppants and chemical additives) are injected at high pressures into the formations, to produce fractures and fissures, and thus to release gas from the source rock into the wellbore. The injected fluids partly remain in the formation, while about 20 to 40% of the originally injected fluid flows back to the surface, together with formation waters, sometimes containing dissolved hydrocarbons, high salt concentrations, etc. The overall production operation will likely affect and be affected by subsurface microbial communities associated to the shale formations. On the one hand microbial activity (like growth, biofilm formation) can cause unwanted processes like corrosion, clogging, etc. On the other hand, the introduction of frac fluids could either enhance microbial growth or cause toxicity to the shale-associated microbial communities. To investigate the potential impacts of changing environmental reservoir conditions, like temperature, salinity, oxgen content and pH, as well as the introduction of frac or geogenic chemicals on subsurface microbial communities, laboratory experiments under in situ conditions (i.e. high temperatures and pressures) are being conducted. Enrichment cultures with samples from several subsurface environments (e.g. shale and coal deposits, gas reservoirs, geothermal fluids) have been set up using a variety of carbon sources, including hydrocarbons and typical frac chemicals. Classical microbiological and molecular analysis are used to determine changes in the microbial abundance, community structure and function after the exposure to different single frac chemicals, "artificial" frac fluids or production waters. On the other hand, potential transformation reactions of frac or geogenic chemicals by subsurface microbiota and their lifetime are investigated. In our "fracking simulation" experiments, an increasing number of hydrocarbon-degrading or halophilic microorganisms is to be expected after exposure of subsurface communities to artificial production waters. Whereas the introduction of freshwater and of easily biodegradable substrates might favor the proliferation of fast-growing generalistic heterotrophs in shale-associated communities. Nevertheless toxicity of some of the frac components cannot be excluded.

Geochemical evidence for possible natural migration of Marcellus Formation brine to shallow aquifers in Pennsylvania

PubMed Central

Warner, Nathaniel R.; Jackson, Robert B.; Darrah, Thomas H.; Osborn, Stephen G.; Down, Adrian; Zhao, Kaiguang; White, Alissa; Vengosh, Avner

2012-01-01

The debate surrounding the safety of shale gas development in the Appalachian Basin has generated increased awareness of drinking water quality in rural communities. Concerns include the potential for migration of stray gas, metal-rich formation brines, and hydraulic fracturing and/or flowback fluids to drinking water aquifers. A critical question common to these environmental risks is the hydraulic connectivity between the shale gas formations and the overlying shallow drinking water aquifers. We present geochemical evidence from northeastern Pennsylvania showing that pathways, unrelated to recent drilling activities, exist in some locations between deep underlying formations and shallow drinking water aquifers. Integration of chemical data (Br, Cl, Na, Ba, Sr, and Li) and isotopic ratios (87Sr/86Sr, 2H/H, 18O/16O, and 228Ra/226Ra) from this and previous studies in 426 shallow groundwater samples and 83 northern Appalachian brine samples suggest that mixing relationships between shallow ground water and a deep formation brine causes groundwater salinization in some locations. The strong geochemical fingerprint in the salinized (Cl > 20 mg/L) groundwater sampled from the Alluvium, Catskill, and Lock Haven aquifers suggests possible migration of Marcellus brine through naturally occurring pathways. The occurrences of saline water do not correlate with the location of shale-gas wells and are consistent with reported data before rapid shale-gas development in the region; however, the presence of these fluids suggests conductive pathways and specific geostructural and/or hydrodynamic regimes in northeastern Pennsylvania that are at increased risk for contamination of shallow drinking water resources, particularly by fugitive gases, because of natural hydraulic connections to deeper formations. PMID:22778445

Geochemical evidence for possible natural migration of Marcellus Formation brine to shallow aquifers in Pennsylvania.

PubMed

Warner, Nathaniel R; Jackson, Robert B; Darrah, Thomas H; Osborn, Stephen G; Down, Adrian; Zhao, Kaiguang; White, Alissa; Vengosh, Avner

2012-07-24

The debate surrounding the safety of shale gas development in the Appalachian Basin has generated increased awareness of drinking water quality in rural communities. Concerns include the potential for migration of stray gas, metal-rich formation brines, and hydraulic fracturing and/or flowback fluids to drinking water aquifers. A critical question common to these environmental risks is the hydraulic connectivity between the shale gas formations and the overlying shallow drinking water aquifers. We present geochemical evidence from northeastern Pennsylvania showing that pathways, unrelated to recent drilling activities, exist in some locations between deep underlying formations and shallow drinking water aquifers. Integration of chemical data (Br, Cl, Na, Ba, Sr, and Li) and isotopic ratios ((87)Sr/(86)Sr, (2)H/H, (18)O/(16)O, and (228)Ra/(226)Ra) from this and previous studies in 426 shallow groundwater samples and 83 northern Appalachian brine samples suggest that mixing relationships between shallow ground water and a deep formation brine causes groundwater salinization in some locations. The strong geochemical fingerprint in the salinized (Cl > 20 mg/L) groundwater sampled from the Alluvium, Catskill, and Lock Haven aquifers suggests possible migration of Marcellus brine through naturally occurring pathways. The occurrences of saline water do not correlate with the location of shale-gas wells and are consistent with reported data before rapid shale-gas development in the region; however, the presence of these fluids suggests conductive pathways and specific geostructural and/or hydrodynamic regimes in northeastern Pennsylvania that are at increased risk for contamination of shallow drinking water resources, particularly by fugitive gases, because of natural hydraulic connections to deeper formations.

Experimental study of droplet formation of dense suspensions

NASA Astrophysics Data System (ADS)

Martensson, Gustaf; Carson, Fabian

2017-11-01

As with the jet printing of dyes and other low-viscosity fluids, the jetting of dense fluid suspensions is dependent on the repeatable break-off of the fluid filament into well-formed droplets. It is well known that the break-off of dense suspensions is dependent on the volume fraction of the solid phase, particle size and morphology, fluid phase viscosity et cetera, see for example van Deen et al. (2013). The purpose of this study is to establish a deeper understanding of the formation process of droplets of dense suspensions. Previous experiments have utilised a filament break-off device (FilBO) developed in-house. These experiments utilise an ejection device based on rapid volumetric displacement of the fluid through a conical nozzle. The suspension samples consist of a resin-based flux and spherical particles with diameters of dp = 5 - 25 μ m. A droplet of of the suspension with a volume of Vdrop = 2 - 50 nl is ejected from the nozzle. Correlations between droplet speed and the temporal development of the volumetric displacement will be presented. Further results relating break-off length and rate versus particle diameter, volume fraction and probe speed will be presented.

Carbon, oxygen and strontium isotopic constraints on fluid sources, temperatures and biogeochemical processes during the formation of seep carbonates - Secchia River site, Northern Apennines

NASA Astrophysics Data System (ADS)

Viola, Irene; Capozzi, Rossella; Bernasconi, Stefano M.; Rickli, Jörg

2017-07-01

Understanding authigenic seep carbonate formation provides clues for hydrocarbon exploration and insights into contributions to gas budgets of marine environments and the atmosphere. Seep carbonates discovered in the outcropping succession along the Secchia riverbanks (near Modena, Italy) belong to the Argille Azzurre Formation of Early Pleistocene age deposited in an upper shelf environment overlying the Miocene foredeep successions, which include hydrocarbon fields. The fluid migration from the hydrocarbon fields, up to the surface, is presently active on land and started in the marine succession during the Late Miocene. Authigenic globular carbonate concretions and carbonate chimneys are interspersed along the strata throughout the section. A comprehensive geochemical characterisation of the carbonates has been carried out to understand the processes leading to their formation. The carbonate concretions are the record of past hydrocarbon vents linked to the Miocene petroleum system of the Northern Apennines. The samples are composed of > 50% microcrystalline dolomite. The δ13C signatures identify two groups in the samples according to different type of formation processes. Globular concretions have positive values that suggest an influence of CO2 associated to secondary methanogenesis due to microbial degradation of higher hydrocarbons. The analysed chimney, with negative δ13C values, is interpreted as former conduit where carbonate precipitation is promoted by Anaerobic Oxidation of Methane coupled with Sulfate Reduction. The δ18O range, coupled with 87/86Sr signatures, indicate that the contribution of deep connate water from the Miocene reservoirs is up to 23% during the formation of the globular concretions. The connate water occurrence is also documented by higher ambient temperatures. The different isotope signatures in seep carbonates result from the relative contribution of the recognised gas and water components, linked to different plumbing systems and fluid supply from a well-defined hydrocarbon field. The seep carbonate characteristics have enlightened variations in biogeochemical processes, which can be rarely quantified in ancient and present-day marine environments.

Using excess 4He to quantify variability in aquitard leakage

NASA Astrophysics Data System (ADS)

Gardner, W. Payton; Harrington, Glenn A.; Smerdon, Brian D.

2012-10-01

SummaryFluid flux through aquitards controls the rate of recharge, discharge, cross-formational fluid flow and contaminant transport in subsurface systems. In this paper, concentrations of 4He are used to investigate the spatial distribution of vertical fluid flux through the regionally extensive Great Artesian Basin aquitard system in northern South Australia. Two vertical profiles of 4He concentration in aquitard pore water, augmented with regional sampling of aquifers above and below the aquitard were used to estimate fluid flux at multiple locations over a large spatial area. 4He concentrations in the shallow aquifer above the Great Artesian Basin range from atmospheric equilibrium to 1000 times enriched over atmosphere. Fluid flux through the aquitard was estimated by fitting observed helium concentrations at each sampling site with a 1-D model of helium transport through the aquitard. Estimated fluid fluxes through the aquitard vary over three orders of magnitude across the study area. In areas of competent aquitard, fluid fluxes are less than 0.003 mm/yr, and mass transport of helium is dominated by molecular diffusion. Preferential discharge zones are clearly identifiable with fluid fluxes up to 3 mm/yr. Our results show that fluid flux through a regionally extensive aquitard can be highly variable at large spatial scales, and that 4He concentrations in aquifers bounding the aquitard system provide a convenient and sensitive method for investigating aquitard flux at the regional scale.

Semi-automated 96-well liquid-liquid extraction for quantitation of drugs in biological fluids.

PubMed

Zhang, N; Hoffman, K L; Li, W; Rossi, D T

2000-02-01

A semi-automated liquid-liquid extraction (LLE) technique for biological fluid sample preparation was introduced for the quantitation of four drugs in rat plasma. All liquid transferring during the sample preparation was automated using a Tomtec Quadra 96 Model 320 liquid handling robot, which processed up to 96 samples in parallel. The samples were either in 96-deep-well plate or tube-rack format. One plate of samples can be prepared in approximately 1.5 h, and the 96-well plate is directly compatible with the autosampler of an LC/MS system. Selection of organic solvents and recoveries are discussed. Also, precision, relative error, linearity and quantitation of the semi automated LLE method are estimated for four example drugs using LC/MS/MS with a multiple reaction monitoring (MRM) approach. The applicability of this method and future directions are evaluated.

Fieldable, real-time enzyme immunoassay kits for drugs on surfaces

NASA Astrophysics Data System (ADS)

Chiappini, Michele W.; Wendel, Gregory J.; Duquette, Peter H.; Hamilton, Martha J.; Chudzik, Stephen J.; Chappa, Ralph A.

1994-03-01

Immunoassays (e.g., RIA, EIA) have been demonstrated to be useful for rapid, convenient detection and semiquantitative analysis of drugs. Thermedics Detection, Inc. manufactures a rapid, sensitive, self-contained, disposable, EIA device, developed by Bio-Metric Systems, Inc., designed to allow untrained personnel to perform in field situations. This format has been developed for drugs in biological fluids and on surfaces. The analyte in the test sample competes with an enzyme-analyte conjugate for a limited number of immobilized antibody sites. The AccuPRESS Test format can detect analytes at 10 ppb in biological fluids, water, and soil, and on surfaces, such as suitcases, vehicles, tables and hands, with positive results indicated by clearly visible color development within 5 minutes. This format is designed to have all dry components and to have an ambient shelf life of greater than one year. The format is available for cocaine and opiate derivatives, including heroin, and is readily adaptable for use with numerous other drugs, explosives, and environmental pollutants.

Mechanical and electromagnetic properties of northern Gulf of Mexico sediments with and without THF hydrates

USGS Publications Warehouse

Lee, J.Y.; Santamarina, J.C.; Ruppel, C.

2008-01-01

Using an oedometer cell instrumented to measure the evolution of electromagnetic properties, small strain stiffness, and temperature, we conducted consolidation tests on sediments recovered during drilling in the northern Gulf of Mexico at the Atwater Valley and Keathley Canyon sites as part of the 2005 Chevron Joint Industry Project on Methane Hydrates. The tested specimens include both unremolded specimens (as recovered from the original core liner) and remolded sediments both without gas hydrate and with pore fluid exchanged to attain 100% synthetic (tetrahydrofuran) hydrate saturation at any stage of loading. Test results demonstrate the extent to which the electromagnetic and mechanical properties of hydrate-bearing marine sediments are governed by the vertical effective stress, stress history, porosity, hydrate saturation, fabric, ionic concentration of the pore fluid, and temperature. We also show how permittivity and electrical conductivity data can be used to estimate the evolution of hydrate volume fraction during formation. The gradual evolution of geophysical properties during hydrate formation probably reflects the slow increase in ionic concentration in the pore fluid due to ion exclusion in closed systems and the gradual decrease in average pore size in which the hydrate forms. During hydrate formation, the increase in S-wave velocity is delayed with respect to the decrease in permittivity, consistent with hydrate formation on mineral surfaces and subsequent crystal growth toward the pore space. No significant decementation/debonding occurred in 100% THF hydrate-saturated sediments during unloading, hence the probability of sampling hydrate-bearing sediments without disturbing the original sediment fabric is greatest for samples in which the gas hydrate is primarily responsible for maintaining the sediment fabric and for which the time between core retrieval and restoration of in situ effective stress in the laboratory is minimized. In evaluating the impact of core retrieval on specimen properties, it is also important to consider how far removed hydrate-bearing samples are from hydrate stability conditions. ?? 2008 Elsevier Ltd.

Hydrothermal oxidation in the Biwabik Iron Formation, MN, USA

NASA Astrophysics Data System (ADS)

Losh, Steven; Rague, Ryan

2018-02-01

Precambrian iron formations throughout the world, notably in Australia, Brazil, and South Africa, show evidence of hypogene (≥ 110 °C, mostly > 250 °C) oxidation, alteration, and silica dissolution as a result of tectonic or magmatic activity. Although hydrothermal oxidation has been proposed for the prototype Lake Superior-type iron formation, the Biwabik Iron Formation in Minnesota (USA), it has not been documented there. By examining oxidized and unoxidized Biwabik Iron Formation in three mines, including material from high-angle faults that are associated with oxidation, we document an early hypogene oxidation event ( 175 °C) involving medium-salinity aqueous fluids (8.4 ± 4.9 wt% NaCl equiv) that infiltrated iron formation along high-angle faults. At the Hibbing Taconite Mine, hydrothermal fluids oxidized iron carbonates and silicates near faults, producing goethite ± quartz. In contrast with much of the oxidized iron ores on the Mesabi Range, silica was not removed but rather recrystallized during this event, perhaps lying in a rock-dominated system at low cumulative fluid flux. During the hydrothermal oxidation event in the Hibbing Taconite deposit, quartz-filled microfractures and irregular inclusions commonly formed in coarse variably oxidized magnetite, currently the ore mineral: these inclusions degrade the ore by introducing excess silica in magnetic concentrate. Hydrothermal oxidation at Hibbing Taconite Mine is overprinted by later, relatively minor supergene oxidation both along faults and near the surface, which locally dissolved quartz. At the Fayal Reserve Mine, widespread silicate and carbonate gangue dissolution and iron oxidation was followed by precipitation of pyrite, Mn-siderite, apatite, and other minerals in void spaces, which prevented post-oxidation compaction and significant volume loss in the sampled rocks. Although definitive temperature data for this assemblage are needed, the weight of evidence indicates that this mineralization is hypogene. The association of oxidation with epithermal conditions constrains the oxidation and subsequent mineralization to have taken place during the Precambrian, the only time when these rocks would have experienced the necessary temperatures. The mineralization at Fayal Reserve shows little supergene overprint: pyrite is largely unoxidized. Hydrothermal oxidation in both mines was likely produced by basinal fluids that were expelled during the 1.83-1.87 Ga Penokean Orogeny, and mixing with meteoric fluids along faults, although a 1.1 Ga rift-related fluid flow event is also possible. Later supergene overprinting of the iron formation was minor.

Portable device and method for determining permeability characteristics of earth formations

DOEpatents

Shuck, Lowell Z.

1977-01-01

The invention is directed to a device which is used for determining permeability characteristics of earth formations at the surface thereof. The determination of the maximum permeability direction and the magnitude of permeability are achieved by employing a device comprising a housing having a central fluid-injection port surrounded by a plurality of spaced-apart fluid flow and pressure monitoring ports radially extending from the central injection port. With the housing resting on the earth formation in a relatively fluid-tight manner as provided by an elastomeric pad disposed therebetween, fluid is injected through the central port into the earth formation and into registry with the fluid-monitoring ports disposed about the injection port. The fluid-monitoring ports are selectively opened and the flow of the fluid through the various fluid ports is measured so as to provide a measurement of flow rates and pressure distribution about the center hole which is indicative on the earth formation permeability direction and magnitude. For example, the azimuthal direction of the fluid-monitoring ports in the direction through which the greatest amount of injected fluid flows as determined by the lowest pressure distribution corresponds to the direction of maximum permeability in the earth formation.

Power systems utilizing the heat of produced formation fluid

DOEpatents

Lambirth, Gene Richard [Houston, TX

2011-01-11

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method includes treating a hydrocarbon containing formation. The method may include providing heat to the formation; producing heated fluid from the formation; and generating electricity from at least a portion of the heated fluid using a Kalina cycle.

Investigating the effects of abyssal peridotite alteration on Si, Mg and Zn isotopes

NASA Astrophysics Data System (ADS)

Savage, P. S.; Wimpenny, J.; Harvey, J.; Yin, Q.; Moynier, F.

2013-12-01

Around 1/3 of Earth's divergent ridge system is now classified as "slow" spreading [1], exposing ultramafic rocks (abyssal peridotites) at the seafloor. Such material is often highly altered by serpentinisation and steatisation (talc formation). It is crucial to understand such processes in order to access the original composition of the mantle, and to quantify any impact on ocean composition. Here we examine the effect of both serpentinisation and steatisation on Si, Mg and Zn isotopes. Hydrothermal alteration and seafloor weathering are both sources of oceanic Si [2] and weathering of abyssal peridotites is a source of oceanic Mg [3]; hence isotopic fractionation as a result of seafloor alteration could affect oceanic Si and Mg isotope composition. Zinc isotopes can provide complimentary information; the magnitude and direction of fractionation is highly dependent on complexing ligand [4] and can provide compositional information on the fluids driving metasomatism. For this study, two cores from the well-characterised abyssal peridotites recovered on ODP Leg 209 were examined [5]. Hole 1274a peridotites exhibit variable serpentinisation at ~200°C, whereas samples from Hole 1268a have been comprehensively serpentinised and then subsequently steatised to talc facies at ~350°C, by a low Mg/Si, low pH fluid. The Si, Mg and Zn isotope compositions of 1274a samples are extremely homogeneous, identical to that of pristine mantle rocks (BSE) i.e., serpentinisation at this locality was predominantly isochemical [5]. In contrast, samples from 1268a show greater isotopic variability. In all samples, Mg is enriched in the heavier isotopes relative to BSE, consistent with formation of isotopically heavy secondary phases [6]. For Si, serpentinised samples are slightly enriched in the lighter isotopes compared to BSE, again consistent with the behaviour of Si during formation of secondary phases [7]. Within the steatised samples, some exhibit enrichments in the lighter Si isotopes (similar to the serpentinites), however, some are isotopically heavy, relative to BSE. Such samples were found to have abundant chlorite, whose formation requires fluid with high Al activity, likely sourced from late-emplaced gabbroic dykes. The Zn of all 1268a samples are enriched in the lighter isotopes, implying the involvement of isotopically light sulfide precipitation during metasomatism [4]. The consistently heavy Mg isotope data suggest that seafloor alteration of peridotites can input an isotopically light Mg-bearing fluid to the ocean. Fluid composition is less easy to determine from the more complex behaviour observed in Si isotopes, although it is unlikely to substantially deviate from BSE, consistent with previous observations [8]. Finally, the strong enrichment in the lighter isotopes of Zn confirms that this isotope system could be used as a tracer of recycled serpentinised material at arc settings, as suggested in [4]. [1] Dick et al. (2003) Nature 426, 405-412; [2] Treguer and De La Rocha (2013) Ann. Rev. Mar. Sci. 5, 477-501; [3] Snow & Dick (1995) GCA, 59, 4219-4235; [4] Pons et al. (2011) PNAS 108(43) 17639-17643; [5] Bach et al., (2004) G3 5; [6] Tipper et al. (2006) EPSL 247, 267-279; [7] Opfergelt et al. (2012) Chem. Geol. 326, 113-122; [8] De La Rocha et al. (2000) GCA 64, 2467-2477.

Analysis of sources of bulk conductivity change in saturated silica sand after unbuffered TCE oxidation by permanganate.

PubMed

Hort, Ryan D; Revil, André; Munakata-Marr, Junko

2014-09-01

Time lapse resistivity surveys could potentially improve monitoring of permanganate-based in situ chemical oxidation (ISCO) of organic contaminants such as trichloroethene (TCE) by tracking changes in subsurface conductivity that result from injection of permanganate and oxidation of the contaminant. Bulk conductivity and pore fluid conductivity changes during unbuffered TCE oxidation using permanganate are examined through laboratory measurements and conductivity modeling using PHREEQC in fluid samples and porous media samples containing silica sand. In fluid samples, oxidation of one TCE molecule produces three chloride ions and one proton, resulting in an increase in fluid electrical conductivity despite the loss of two permanganate ions in the reaction. However, in saturated sand samples in which up to 8mM TCE was oxidized, at least 94% of the fluid conductivity associated with the presence of protons was removed within 3h of sand contact, most likely through protonation of silanol groups found on the surface of the sand grains. Minor conductivity effects most likely associated with pH-dependent reductive dissolution of manganese dioxide were also observed but not accounted for in pore-fluid conductivity modeling. Unaccounted conductivity effects resulted in an under-calculation of post-reaction pore fluid conductivity of 2.1% to 5.5%. Although small increases in the porous media formation factor resulting from precipitation of manganese dioxide were detected (about 3%), these increases could not be confirmed to be statistically significant. Both injection of permanganate and oxidation of TCE cause increases in bulk conductivity that would be detectable through time-lapse resistivity surveys in field conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Polymeric nanospheres as a displacement fluid in enhanced oil recovery

NASA Astrophysics Data System (ADS)

Hendraningrat, Luky; Zhang, Julien

2015-12-01

This paper presents the investigation of using nanoscale polyacrylamide-based spheres (nanospheres) as a displacement fluid in enhanced oil recovery (EOR). Coreflood experiments were conducted to evaluate the impact of nanospheres and its concentration dispersed in model formation water on oil recovery during a tertiary oil recovery process. The coreflood results showed that nanospheres can enhance residual oil recovery in the sandstone rock samples and its concentration showed a significant impact into incremental oil. By evaluating the contact angle, it was observed that wettability alteration also might be involved in the possible oil displacement mechanism in this process together with fluid behavior and permeability to water that might divert injected fluid into unswept oil areas and enhance the residual oil recovery. These investigations promote nanospheres aqueous disperse solution as a potential displacement fluid in EOR.

Hydrogen, Oxygen and Silicon Isotope Systematics of Groundwater-Magma Interaction in Icelandic Hydrothermal Systems

NASA Astrophysics Data System (ADS)

Kleine, B. I.; Stefansson, A.; Halldorsson, S. A.; Martin, W.; Barnes, J.; Jónasson, K.; Franzson, H.

2016-12-01

Magma often encounters groundwater (meteoric or seawater derived) when intruded into the crust. Magma-groundwater interactions result in the formation of hydrothermal fluids which can lead to contact metamorphism and elemental transport in the country rock. In fact, magma-hydrothermal fluid interaction (rather than magma-magmatic fluid interaction) may lead to classic contact metamorphic reactions. In order to explore the importance of hydrothermal fluid during contact metamorphism we use stable isotopes (δD, δ18O, δ30Si) from both active and extinct magma chambers and hydrothermal systems from across Iceland. Quartz grains from various hydrothermal systems, from crustal xenoliths from the Askja central volcano and from the Hafnarfjall pluton, as well as quartz grains associated with low-T zeolites were analysed for δ18O and δ30Si in-situ using SIMS. Whole rock material of these samples was analysed for δD values using a TCEA coupled to an IRMS. Our results indicate that low-T quartz (<150°C) are dominated by negative δ30Si values whereas positive δ30Si values prevail in quartz precipitated at higher T (>300°C). Combining the results from the analyses of δ18O and δD allows further division of samples into (i) seawater and/or rock dominated and (ii) meteoric water dominated hydrothermal systems. In order to isolate the effects of fluid-rock interaction, fluid source and formation temperature at the magma-groundwater contact, δD, δ18O and δ30Si values of rocks and fluids were modeled using the PHREEQC software. Comparison of analytical and model results shows that the isotopic compositions are influenced by multiple processes. In some cases, groundwater penetrates the contact zone and causes alteration at >400°C by groundwater-magma heat interaction. Other cases document "baked" contact zones without groundwater. Our analyses and modeling demonstrates that groundwater flow and permeability are crucial in setting the style of contact metamorphism around high T intrusions.

Sulfur Isotope Analysis of Minerals and Fluids in a Natural CO2 Reservoir, Green River, Utah

NASA Astrophysics Data System (ADS)

Chen, F.; Kampman, N.; Bickle, M. J.; Busch, A.; Turchyn, A. V.

2013-12-01

Predicting the security of geological CO2 storage sites requires an understanding of the geochemical behavior of the stored CO2, especially of fluid-rock reactions in reservoirs, caprocks and fault zones. Factors that may influence geochemical behavior include co-injection of sulfur gases along with the CO2, either in acid-gas disposal or as contaminants in CO2 storage sites, and microbial activity, such as bacterial sulfate reduction. The latter may play an important role in buffering the redox chemistry of subsurface fluids, which could affect toxic trace metal mobilization and transport in acidic CO2-rich fluids. These processes involving sulfur are poorly understood. Natural CO2-reservoirs provide natural laboratories, where the flow and reactions of the CO2-charged fluids and the activity of microbial communities are integrated over sufficient time-scales to aid prediction of long-term CO2 storage. This study reports on sulfur isotope analyses of sulfate and sulfide minerals in rock core and in CO2-charged fluids collected from a stacked sequence of natural CO2 reservoirs at Green River, Utah. Scientific drilling adjacent to a CO2-degassing normal fault to a depth of 325m retrieved core and fluid samples from two CO2 reservoirs in the Entrada and Navajo Sandstones and from the intervening Carmel Formation caprock. Fluid samples were collected from CO2-charged springs that discharge through the faults. Sulfur exists as sulfate in the fluids, as sedimentary gypsum beds in the Carmel Formation, as remobilized gypsum veins within a fault damage zone in the Carmel Fm. and in the Entrada Sandstone, and as disseminated pyrite and pyrite-mineralized open fractures throughout the cored interval. We use the stable sulfur (δ34S) and oxygen (δ18OSO4) isotopes of the sulfate, gypsum, and pyrite to understand the source of sulfur in the reservoir as well as the timing of gypsum vein and pyrite formation. The hydration water of the gypsum is also reported to explore the different timing of gypsum vein formation. Macroscopic and microscopic gradients in the sulfur isotope composition of pyrite throughout the core and at discernible redox-reaction fronts were examined in detail to assess the role of bacteria in mediating sulfate reduction, sulfide mineralization and buffering of groundwater redox chemistry. The CO2 charged fluids and gypsum veins within the Entrada Sandstone have a narrow and very similar range in both δ34SSO4 and δ18OSO4, suggesting that the fluids (9.1-10.7‰) are the most likely source of the sulfate in the veins (11.4-12.8‰) and that the veins formed during recent fluid flow through the Entrada, with sulfate coming from remobilized gypsum beds in the Carmel. The Carmel also contains two isotopically distinct types of gypsum veins: one with δ34SSO4 values similar to the Entrada veins and one with much higher δ34SSO4 values (15.1-16.1‰). The latter are likely primary gypsum, while the former are likely secondary gypsum. Sulfur isotope fractionation between pyrite (-16.5‰ to -35.7‰) at the Carmel-Navajo interface and reservoir fluids (9.1-10.7‰) suggest that sulfur reducing bacteria play a role in producing the deposited sulfide. This data demonstrates active sulfur cycling in CO2 reservoirs with many different sulfur species cycled among various pools creating the wide isotope dispersion we observe.

High Throughput Strontium Isotope Method for Monitoring Fluid Flow Related to Geological CO2 Storage

NASA Astrophysics Data System (ADS)

Capo, R. C.; Wall, A. J.; Stewart, B. W.; Phan, T. T.; Jain, J. C.; Hakala, J. A.; Guthrie, G. D.

2012-12-01

Natural isotope tracers, such as strontium (Sr), can be a unique and powerful component of a monitoring strategy at a CO2 storage site, facilitating both the quantification of reaction progress for fluid-rock interactions and the tracking of brine migration caused by CO2 injection. Several challenges must be overcome, however, to enable the routine use of isotopic tracers, including the ability to rapidly analyze numerous aqueous samples with potentially complex chemical compositions. In a field situation, it might be necessary to analyze tens of samples over a short period of time to identify subsurface reactions and respond to unexpected fluid movement in the host formation. These conditions require streamlined Sr separation chemistry for samples ranging from pristine groundwaters to those containing high total dissolved solids, followed by rapid measurement of isotope ratios with high analytical precision. We have optimized Sr separation chemistry and MC-ICP-MS methods to provide rapid and precise measurements of isotope ratios in geologic, hydrologic, and environmental samples. These improvements will allow an operator to independently prepare samples for Sr isotope analysis off-site using fast, low cost chemical separation procedures and commercially available components. Existing vacuum-assisted Sr separation procedures were modified by using inexpensive disposable parts to eliminate cross contamination. Experimental results indicate that the modified columns provide excellent separation of Sr from chemically complex samples and that Sr can be effectively isolated from problematic matrix elements (e.g., Ca, Ba, K) associated with oilfield brines and formation waters. The separation procedure is designed for high sample throughput in which batches of 24 samples can be processed in approximately 2 hours, and are ready for Sr isotope measurements by MC-ICP-MS immediately after collection from the columns. Precise Sr isotope results can be achieved by MC-ICP-MS with a throughput of 4 to 5 samples per hour. Our mean measured value of NIST Sr isotope standard SRM 987 is 0.710265 ± 0.000014 (2σ, n = 94). A range of brines and CO2-rich fluids analyzed by this method yielded results within the analytical uncertainty of 87Sr/86Sr ratios previously determined by standard column separation and thermal ionization mass spectrometry. This method provides a fast and effective way to use Sr isotopes for monitoring purposes related to geological CO2 storage.

Vertical hydraulic conductivity of a clayey-silt aquitard: accelerated fluid flow in a centrifuge permeameter compared with in situ conditions

NASA Astrophysics Data System (ADS)

Timms, W. A.; Crane, R.; Anderson, D. J.; Bouzalakos, S.; Whelan, M.; McGeeney, D.; Rahman, P. F.; Guinea, A.; Acworth, R. I.

2014-03-01

Evaluating the possibility of leakage through low permeability geological strata is critically important for sustainable water supplies, extraction of fuels from strata such as coal beds, and confinement of waste within the earth. Characterizing low or negligible flow rates and transport of solutes can require impractically long periods of field or laboratory testing, but is necessary for evaluations over regional areas and over multi-decadal timescales. The current work reports a custom designed centrifuge permeameter (CP) system, which can provide relatively rapid and reliable hydraulic conductivity (K) measurement compared to column permeameter tests at standard gravity (1g). Linear fluid velocity through a low K porous sample is linearly related to g-level during a CP flight unless consolidation or geochemical reactions occur. The CP module is designed to fit within a standard 2 m diameter, geotechnical centrifuge with a capacity for sample dimensions of 30 to 100 mm diameter and 30 to 200 mm in length. At maximum RPM the resultant centrifugal force is equivalent to 550g at base of sample or a total stress of ~2 MPa. K is calculated by measuring influent and effluent volumes. A custom designed mounting system allows minimal disturbance of drill core samples and a centrifugal force that represents realistic in situ stress conditions is applied. Formation fluids were used as influent to limit any shrink-swell phenomena which may alter the resultant K value. Vertical hydraulic conductivity (Kv) results from CP testing of core from the sites in the same clayey silt formation varied (10-7 to 10-9 m s-1, n = 14) but higher than 1g column permeameter tests of adjacent core using deionized water (10-9 to 10-11 m s-1, n = 7). Results at one site were similar to in situ Kv values (3 × 10-9 m s-1) from pore pressure responses within a 30 m clayey sequence in a homogenous area of the formation. Kv sensitivity to sample heterogeneity was observed, and anomalous flow via preferential pathways could be readily identified. Results demonstrate the utility of centrifuge testing for measuring minimum K values that can contribute to assessments of geological formations at large scale. The importance of using realistic stress conditions and influent geochemistry during hydraulic testing is also demonstrated.

Petrography and chemistry of SiO 2 filling phases in the amethyst geodes from the Serra Geral Formation deposit, Rio Grande do Sul, Brazil

NASA Astrophysics Data System (ADS)

Commin-Fischer, Adriane; Berger, Gilles; Polvé, Mireille; Dubois, Michel; Sardini, Paul; Beaufort, Daniel; Formoso, Milton

2010-04-01

The filling process of amethyst-bearing geodes from Serra Geral Formation basalts, Brazil, is investigated by different methods performed on the SiO 2 filling phases. Image analysis of quartz-amethyst deposits suggests a single growing mechanism ruled by geometric selection of randomly oriented crystals. Microthermometry of fluid inclusions reveals formation temperature lower than 100 °C, probably lower than 50 °C, and fluid salinity as high as 3 mass% NaCl eq. Composition in REE and trace-elements measured by ICP-MS on acid-digested or laser-ablated samples indicates a common genesis for amethyst, quartz and chalcedony, as well as the absence of significant variations from one geode to another. 87Sr/ 86Sr data on chalcedony shows that both the host basalt or the Botucatu sandstone are possible silica sources. These data, combined with thermo-kinetic considerations, permit us to discuss the filling process. We argue in favor of the contribution of a mineralized fluid of hydrothermal origin producing a regional silica source which decreased with time. The observed mineral sequence is related to the depletion of silica in the solution.

Rare earths in the Leadville Limestone and its marble derivates

USGS Publications Warehouse

Jarvis, J.C.; Wildeman, T.R.; Banks, N.G.

1975-01-01

Samples of unaltered and metamorphosed Leadville Limestone (Mississippian, Colorado) were analyzed by neutron activation for ten rare-earth elements (REE). The total abundance of the REE in the least-altered limestone is 4-12 ppm, and their distribution patterns are believed to be dominated by the carbonate minerals. The abundances of the REE in the marbles and their sedimentary precursors are comparable, but the distribution patterns are not. Eu is enriched over the other REE in the marbles, and stratigraphically upward in the formation (samples located progressively further from the heat source), the light REE become less enriched relative to the heavy REE. The Eu anomaly is attributed to its ability, unique among the REE, to change from the 3+ to 2+ oxidation state. Whether this results in preferential mobilization of the other REE or whether this reflects the composition of the pore fluid during metamorphism is unknown. Stratigraphically selective depletion of the heavy REE may be attributed to more competition for the REE between fluid and carbonate minerals in the lower strata relative to the upper strata. This competition could have been caused by changes in the temperature of the pore fluid or to the greater resistance to solution of the dolomite in the lower parts of the formation than the calcite in the upper parts. ?? 1975.

Impact to Underground Sources of Drinking Water and Domestic Wells from Production Well Stimulation and Completion Practices in the Pavillion, Wyoming, Field.

PubMed

DiGiulio, Dominic C; Jackson, Robert B

2016-04-19

A comprehensive analysis of all publicly available data and reports was conducted to evaluate impact to Underground Sources of Drinking Water (USDWs) as a result of acid stimulation and hydraulic fracturing in the Pavillion, WY, Field. Although injection of stimulation fluids into USDWs in the Pavillion Field was documented by EPA, potential impact to USDWs at the depths of stimulation as a result of this activity was not previously evaluated. Concentrations of major ions in produced water samples outside expected levels in the Wind River Formation, leakoff of stimulation fluids into formation media, and likely loss of zonal isolation during stimulation at several production wells, indicates that impact to USDWs has occurred. Detection of organic compounds used for well stimulation in samples from two monitoring wells installed by EPA, plus anomalies in major ion concentrations in water from one of these monitoring wells, provide additional evidence of impact to USDWs and indicate upward solute migration to depths of current groundwater use. Detections of diesel range organics and other organic compounds in domestic wells <600 m from unlined pits used prior to the mid-1990s to dispose diesel-fuel based drilling mud and production fluids suggest impact to domestic wells as a result of legacy pit disposal practices.

Role of CT scanning in formation evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bergosh, J.L.; Dibona, B.G.

1988-01-01

The use of the computerized tomographic (CT) scanner in formation evaluation of difficult to analyze core samples has moved from the research and development phase to daily, routine use in the core-analysis laboratory. The role of the CT scanner has become increasingly important as geologists try to obtain more representative core material for accurate formation evaluation. The most common problem facing the core analyst when preparing to measure petrophysical properties is the selection of representative and unaltered core samples for routine and special core testing. Recent data have shown that heterogeneous reservoir rock can be very difficult, if not impossible,more » to assess correctly when using standard core examination procedures, because many features, such as fractures, are not visible on the core surface. Another problem is the invasion of drilling mud into the core sample. Flushing formation oil and water from the core can greatly alter the saturation and distribution of fluids and lead to serious formation evaluation problems. Because the quality and usefulness of the core date are directly tied to proper sample selection, it has become imperative that the CT scanner be used whenever possible.« less

Microbial life in cold, hydrologically active oceanic crustal fluids

NASA Astrophysics Data System (ADS)

Meyer, J. L.; Jaekel, U.; Girguis, P. R.; Glazer, B. T.; Huber, J. A.

2012-12-01

It is estimated that at least half of Earth's microbial biomass is found in the deep subsurface, yet very little is known about the diversity and functional roles of these microbial communities due to the limited accessibility of subseafloor samples. Ocean crustal fluids, which may have a profound impact on global nutrient cycles given the large volumes of water moving through the crustal aquifer, are particularly difficult to sample. Access to uncontaminated ocean crustal fluids is possible with CORK (Circulation Obviation Retrofit Kit) observatories, installed through the Integrated Ocean Drilling Program (IODP). Here we present the first microbiological characterization of the formation fluids from cold, oxygenated igneous crust at North Pond on the western flank of the Mid Atlantic Ridge. Fluids were collected from two CORKs installed at IODP boreholes 1382A and 1383C and include fluids from three different depth horizons within oceanic crust. Collection of borehole fluids was monitored in situ using an oxygen optode and solid-state voltammetric electrodes. In addition, discrete samples were analyzed on deck using a comparable lab-based system as well as a membrane-inlet mass spectrometer to quantify all dissolved volatiles up to 200 daltons. The instruments were operated in parallel and both in situ and shipboard geochemical measurements point to a highly oxidized fluid, revealing an apparent slight depletion of oxygen in subsurface fluids (~215μM) relative to bottom seawater (~245μM). We were unable to detect reduced hydrocarbons, e.g. methane. Cell counts indicated the presence of roughly 2 x 10^4 cells per ml in all fluid samples, and DNA was extracted and amplified for the identification of both bacterial and archaeal community members. The utilization of ammonia, nitrate, dissolved inorganic carbon, and acetate was measured using stable isotopes, and oxygen consumption was monitored to provide an estimate of the rate of respiration per cell per day. These results provide the first dataset describing the diversity of microbes present in cold, oxygenated ocean crustal fluids and the biogeochemical processes they mediate in the subseafloor.

Vesicles in Apollo 15 Green Glasses: The Nature of Ancient Lunar Gases

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Clemett, S. J.; Berger, E. L.; Rahman, Z.; McKay, D. S.; Gibson, E. K.; Wentworth, S. J.

2014-01-01

Detailed studies of Apollo 15 green glass and related beads have shown they were formed in gas-rich fire fountains.. As the magmatic fluid became super-saturated in volatile gas, bubbles or vesicles formed within the magma. These exsolved gases became trapped within vesicles as the glasses were ejected from the fire-fountain and subsequently quenched. One of the keys to understanding formation processes on the ancient moon includes determining the composition of volatile species and elements, including metals, dissolved in magmatic gases. Here we report the nature of mineral phases spatially associated with vesicles in a green glass bead from Apollo sample 15411,42. The phases reflect the composition of the cooling/degassing magmatic vapors and fluids present at the time of bead formation approx, 3 Ga ago

Melatonin in human preovulatory follicular fluid

NASA Technical Reports Server (NTRS)

Brzezinski, Amnon; Seibel, Machelle M.; Lynch, Harry J.; Deng, Mei-Hua; Wurtman, Richard J.

1987-01-01

Melatonin, the major hormone of the pineal gland, has antigonadotrophic activity in many mammals and may also be involved in human reproduction. Melatonin suppresses steroidogenesis by ovarian granulosa and luteal cells in vitro. To determine if melatonin is present in the human ovary, preovulatory follicular fluids (n = 32) from 15 women were assayed for melatonin by RIA after solvent extraction. The fluids were obtained by laparoscopy or sonographically controlled follicular puncture from infertile women undergoing in vitro fertilization and embryo transfer. All patients had received clomiphene citrate, human menopausal gonadotropin, and hCG to stimulate follicle formation. Blood samples were obtained by venipuncture 30 rain or less after follicular aspiration. All of the follicular fluids contained melatonim, in concentrations substantially higher than those in the corresponding serum. A positive correlation was found between follicular fluid and serum melatonin levels in each woman; these observations indicate that preovulatory follicles contain substantial amounts of melatonin that may affect ovarian steroidogenesis.

How metalliferous brines line Mexican epithermal veins with silver

PubMed Central

Wilkinson, Jamie J.; Simmons, Stuart F.; Stoffell, Barry

2013-01-01

We determined the composition of ~30-m.y.-old solutions extracted from fluid inclusions in one of the world's largest and richest silver ore deposits at Fresnillo, Mexico. Silver concentrations average 14 ppm and have a maximum of 27 ppm. The highest silver, lead and zinc concentrations correlate with salinity, consistent with transport by chloro-complexes and confirming the importance of brines in ore formation. The temporal distribution of these fluids within the veins suggests mineralization occurred episodically when they were injected into a fracture system dominated by low salinity, metal-poor fluids. Mass balance shows that a modest volume of brine, most likely of magmatic origin, is sufficient to supply the metal found in large Mexican silver deposits. The results suggest that ancient epithermal ore-forming events may involve fluid packets not captured in modern geothermal sampling and that giant ore deposits can form rapidly from small volumes of metal-rich fluid. PMID:23792776

In search of ancient biomarkers: Using femtosecond - Laser Desorption Post Ionization - Mass Spectrometry (fs-LDPI-MS) to map organic compounds within ca. 2.7 Ga samples from the Abitibi greenstone belt, Ontario, Canada

NASA Astrophysics Data System (ADS)

Pasterski, M. J.; Barry, G.; Hanley, L.; Kenig, F. P. H.

2016-12-01

One of the major challenges within the field of organic geochemistry is to determine whether an observed biomarker signature was emplaced during sedimentation (indigenous), after sedimentation via the post-depositional migration of fluids (non-indigenous), or during sampling, storage, or analysis (contaminant). Current geochemical techniques (e.g. gas chromatography-mass spectrometry, GC-MS and GCxGC-MS) can effectively determine the composition and structure of the organic constituents of a sample. However, because of the multiple preparatory steps necessary prior to GC-MS analysis (sample crushing, solvent extraction, organic fraction separation) it is impossible to precisely determine the spatial relationship between the host sample and the organic molecules within. We used an MS imaging method developed by Prof. Luke Hanley at the University of Illinois at Chicago, femtosecond-laser desorption post ionization-MS (fs-LDPI-MS), to map the organics within previously characterized ca.2.7 billion year old (Ga) metasediments from the Abitibi greenstone belt near Timmins, ON, Canada. We then compared the MS images to petrographic observations that displayed the distribution of mineral species with well constrained mineralization ages as well as fluid inclusions within the samples. Fluid inclusions are formed during mineralization and have the ability to remain intact over long timescales (up to billions of years), protecting the fluids inside from the introduction of non-indigenous and contaminant biomarkers. Although migrating post-depositional fluids can remineralize sediments, fluid inclusions associated with secondary additions are focused along grain boundaries and microfractures (secondary inclusions), thus, inclusions which are located within grain boundaries can be considered primary and the age of their formation can be determined relative to the host rock. Preliminary results indicate that previously observed biomarkers may be linked to a series of hydrothermal events which occurred regionally ca. 2.64 Ga.

Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin

USGS Publications Warehouse

Phan, Thai T.; Capo, Rosemary C; Stewart, Brian W.; Macpherson, Gwen; Rowan, Elisabeth L.; Hammack, Richard W.

2015-01-01

In Greene Co., southwest Pennsylvania, the Upper Devonian sandstone formation waters have δ7Li values of + 14.6 ± 1.2 (2SD, n = 25), and are distinct from Marcellus Shale formation waters which have δ7Li of + 10.0 ± 0.8 (2SD, n = 12). These two formation waters also maintain distinctive 87Sr/86Sr ratios suggesting hydrologic separation between these units. Applying temperature-dependent illitilization model to Marcellus Shale, we found that Li concentration in clay minerals increased with Li concentration in pore fluid during diagenetic illite-smectite transition. Samples from north central PA show a much smaller range in both δ7Li and 87Sr/86Sr than in southwest Pennsylvania. Spatial variations in Li and δ7Li values show that Marcellus formation waters are not homogeneous across the Appalachian Basin. Marcellus formation waters in the northeastern Pennsylvania portion of the basin show a much smaller range in both δ7Li and 87Sr/86Sr, suggesting long term, cross-formational fluid migration in this region. Assessing the impact of potential mixing of fresh water with deep formation water requires establishment of a geochemical and isotopic baseline in the shallow, fresh water aquifers, and site specific characterization of formation water, followed by long-term monitoring, particularly in regions of future shale gas development.

The physical hydrology of magmatic-hydrothermal systems: High-resolution 18O records of magmatic-meteoric water interaction from the Yankee Lode tin deposit (Mole Granite, Australia)

NASA Astrophysics Data System (ADS)

Fekete, Szandra; Weis, Philipp; Driesner, Thomas; Heinrich, Christoph A.; Baumgartner, Lukas; Bouvier, Anne-Sophie

2016-04-01

Magmatic-hydrothermal ore deposits are important economic Cu, Au, Mo and Sn resources (Sillitoe, 2010, Kesler, 1994). The ore formation is a result of superimposed enrichment processes and metals can precipitate due to fluid-rock interaction and/or temperature drop caused by convection or mixing with meteoric fluid (Heinrich and Candela 2014). Microthermometry and LA-ICP MS trace element analyses of fluid inclusions of a well-characterized quartz sample from the Yankee Lode quartz-cassiterite vein deposit (Mole Granite, Australia) suggest that tin precipitation was driven by dilution of hot magmatic water by meteoric fluids (Audétat et al.1998). High resolution in situ oxygen isotope measurements of quartz have the potential to detect changing fluid sources during the evolution of a hydrothermal system. We analyzed the euhedral growth zones of this previously well-studied quartz sample. Growth temperatures are provided by Audétat et al. (1998) and Audétat (1999). Calculated δ 18O values of the quartz- and/or cassiterite-precipitating fluid show significant variability through the zoned crystal. The first and second quartz generations (Q1 and Q2) were precipitated from a fluid of magmatic isotopic composition with δ 18O values of ˜ 8 - 10 ‰. δ 18O values of Q3- and tourmaline-precipitating fluids show a transition from magmatic δ 18O values of ˜ 8 ‰ to ˜ -5 ‰. The outermost quartz-chlorite-muscovite zone was precipitated from a fluid with a significant meteoric water component reflected by very light δ 18O values of about -15 ‰ which is consistent with values found by previous studies (Sun and Eadington, 1987) using conventional O-isotope analysis of veins in the distal halo of the granite intrusion. Intense incursion of meteoric water during Q3 precipitation (light δ 18O values) agrees with the main ore formation event, though the first occurrence of cassiterite is linked to Q2 precipitating fluid with magmatic-like isotope signature. This apparent discrepancy can be explained by the presence of a fluid of meteoric origin that was isotopically equilibrated with a hot, but already solidified and fractured granitic intrusion under rock-dominated conditions prior their transfer to the cold ore deposition site (Heinrich, 1990). Conversely, in porphyry copper systems meteoric fluid incursion has been assumed to participate in formation of peripheral or post-mineralization processes (Bowman et al., 1987; Sillitoe, 2010; Williams-Jones and Migdisov, 2014). However, recent numerical simulations of porphyry copper systems identify a significant role of meteoric fluids for the enrichment process, providing a cooling mechanism for metal-rich fluids expelled from an upper crustal magma chamber (Weis et al. 2012, Weis 2015). Furthermore, new petrographic and fluid inclusion work of ore-mineralized quartz veins (Landtwing et al., 2010; Stefanova et al., 2014) indicates lower (˜ 450r{ }C) than magmatic fluid temperatures for copper precipitation. Given that the Yankee Lode study validated the capability of high resolution, in situ δ 18O analysis to trace meteoric water incursion, we will apply this method to hydrothermal quartz samples from two significant porphyry copper deposits (Bingham Canyon, USA and Elatsite, Bulgaria). By this we intend to better constrain a potential role of meteoric water incursion in porphyry copper ore precipitation. REFERENCES Audétat, A., Günther, D., Heinrich, C. A. 1998: Formation of a Magmatic-Hydrothermal Ore Deposit: Insights with LA-ICP-MS Analysis of Fluid Inclusions: Science, 279, 2091-2094. Audétat, A. 1999: The magmatic-hydrothermal evolution of the Sn/W-mineralized Mole Granite (Eastern Australia): PhD Thesis, 211. Bowman, J. R., Parry, W. T., Kropp, W. P., and Kruer, S. A., 1987: Chemical and isotopic evolution of hydrothermal solutions at Bingham, Utah: Economic Geology, 82, 395-428. Heinrich, C.A. 1990: The Chemistry of Hydrothermal Tin(-Tungsten) Ore Deposition: Economic Geology, 85, 457-481. Heinrich, C. A., and Candela, P. A. 2014: 13.1 - Fluids and Ore Formation in the Earth's Crust, in Holland, H. D., and Turekian, K. K., eds., Treatise on Geochemistry (Second Edition): Oxford, Elsevier, 1-28. Kesler, S. E., 1994: Mineral Resources, economics and the environment, New York, McMillan, 391. Sillitoe, R. H., 2010: Porphyry copper systems: Economic Geology (Invited Special Paper), 105, 3-41. Sun, S. and Eadington, J. 1987: Oxygen Isotope Evidence for the Mixing of Magmatic and Meteoric Waters during Tin Mineralization in the Mole Granite, New South Wales, Australia: Economic Geology, 82, 43-52. Weis, P., Driesner, T., & Heinrich, C.A. 2012: Porphyry-Copper Ore Shells Form At Stable Pressure Temperature Fronts Within Dynamic Fluid Plumes: Science, 338, 1613-1616. Williams-Jones, A. E., and Migdisov, A. A., 2014: Experimental Constraints on the Transport and Deposition of Metals in Ore-Forming Hydrothermal Systems: Economic Geology, Special Publication, 18, 77-95.

Systems and methods for multi-fluid geothermal energy systems

DOEpatents

Buscheck, Thomas A.

2017-09-19

A method for extracting geothermal energy from a geothermal reservoir formation. A production well is used to extract brine from the reservoir formation. At least one of nitrogen (N.sub.2) and carbon dioxide (CO.sub.2) may be used to form a supplemental working fluid which may be injected into a supplemental working fluid injection well. The supplemental working fluid may be used to augment a pressure of the reservoir formation, to thus drive a flow of the brine out from the reservoir formation.

Hydrologic and water-chemistry data from the Cretaceous-aquifers test well (BFT-2055), Beaufort County, South Carolina

USGS Publications Warehouse

Landmeyer, J.E.; Bradley, P.M.

1998-01-01

Test well BFT-2055 was drilled through the entire thickness of Coastal Plain sediments beneath central Hilton Head Island, South Carolina, and terminated in bedrock at a depth of 3833 feet. The well was drilled to evaluate the hydraulic properties of the Cretaceous formations beneath Hilton Head Island as a potential source of supplemental water to supplies currently withdrawn from the Upper Floridan aquifer. The intervals tested include sediments of the Cape Fear and Middendorf Formations. Results from aquifer tests indicate that the transmissivity of the formations screened ranges from 1300 to 3000 feet squared per day and an average hydraulic conductivity of about 15 feet per day. Formation-fluid pressure tests indicate that the potential exists for upward ground-water flow from higher fluid pressures in the deeper Cape Fear and Middendorf Formations to lower fluid pressures in the Black Creek Formation and shallower units. A flowmeter test indicated that greater than 75 percent of the natural, unpumped flow in the well is from the screened intervals no deeper than 3100 feet. Water-chemistry analyses indicate that the water sampled from the Middendorf and Cape Fear has about 1450 milligrams per liter dissolved solids, 310 to 1000 milligrams per liter sodium, and 144 to 1600 milligrams per liter chloride. Because these chloride concentrations would render water pumped from these aquifers as nonpotable, it is unlikely that these aquifers will be used as a supplemental source of water for island residents without some form of pretreatment. Similar chloride concentrations are present in some wells in the Upper Floridan aquifer adjacent to Port Royal Sound, and these chloride concentrations were the primary reason for drilling the test well in the Cretaceous formations as a possible source of more potable water.

Treating nahcolite containing formations and saline zones

DOEpatents

Vinegar, Harold J

2013-06-11

A method for treating a nahcolite containing subsurface formation includes removing water from a saline zone in or near the formation. The removed water is heated using a steam and electricity cogeneration facility. The heated water is provided to the nahcolite containing formation. A fluid is produced from the nahcolite containing formation. The fluid includes at least some dissolved nahcolite. At least some of the fluid is provided to the saline zone.

Porosity estimates on basaltic basement samples using the neutron absorption cross section (Σ): Implications for fluid flow and alteration of the oceanic crust

NASA Astrophysics Data System (ADS)

Reichow, M. K.; Brewer, T. S.; Marvin, L. G.; Lee, S. V.

2008-12-01

Little information presently exists on the heterogeneity of hydrothermal alteration in the oceanic crust or the variability of the associated thermal, fluid, and chemical fluxes. Formation porosities are important controls on these fluxes and porosity measurements are routinely collected during wireline logging operations. These estimates on the formation porosity are measures of the moderating power of the formation in response to bombardment by neutrons. The neutron absorption macroscopic cross-section (Σ = σρ) is a representation of the ability of the rock to slow down neutrons, and as such can be used to invert the porosity of a sample. Boron, lithium and other trace elements are important controls on σ-values, and the distribution of these is influenced by secondary low-temperature alteration processes. Consequently, computed σ-values may be used to discriminate between various basalt types and to identify areas of secondary alteration. Critical in this analysis is the degree of alteration, since elements such as B and Li can dramatically affect the sigma value and leading to erroneous porosity values. We analysed over 150 'pool-samples' for S, Li, Be and B element concentrations to estimate their contribution to the measured neutron porosity. These chemical analyses allow the calculation of the model sigma values for individual samples. Using a range of variably altered samples recovered during IODP Expeditions 309 and 312 we provide bulk estimates of alteration within the drilled section using the measured neutron porosity. B concentration in Hole 1256D increases with depth, with sharp rises at 959 and 1139 mbsf. Elevated wireline neutron porosities cannot always be directly linked with high B content. However, our preliminary results imply that increased neutron porosity (~15) at depths below 1100 mbsf may reflect hydrothermal alteration rather than formation porosity. This interpretation is supported when compared with generally lower computed porosity estimates derived from resistivity measurements for the same intervals.

Numerical analysis of wellbore instability in gas hydrate formation during deep-water drilling

NASA Astrophysics Data System (ADS)

Zhang, Huaiwen; Cheng, Yuanfang; Li, Qingchao; Yan, Chuanliang; Han, Xiuting

2018-02-01

Gas hydrate formation may be encountered during deep-water drilling because of the large amount and wide distribution of gas hydrates under the shallow seabed of the South China Sea. Hydrates are extremely sensitive to temperature and pressure changes, and drilling through gas hydrate formation may cause dissociation of hydrates, accompanied by changes in wellbore temperatures, pore pressures, and stress states, thereby leading to wellbore plastic yield and wellbore instability. Considering the coupling effect of seepage of drilling fluid into gas hydrate formation, heat conduction between drilling fluid and formation, hydrate dissociation, and transformation of the formation framework, this study established a multi-field coupling mathematical model of the wellbore in the hydrate formation. Furthermore, the influences of drilling fluid temperatures, densities, and soaking time on the instability of hydrate formation were calculated and analyzed. Results show that the greater the temperature difference between the drilling fluid and hydrate formation is, the faster the hydrate dissociates, the wider the plastic dissociation range is, and the greater the failure width becomes. When the temperature difference is greater than 7°C, the maximum rate of plastic deformation around the wellbore is more than 10%, which is along the direction of the minimum horizontal in-situ stress and associated with instability and damage on the surrounding rock. The hydrate dissociation is insensitive to the variation of drilling fluid density, thereby implying that the change of the density of drilling fluids has a minimal effect on the hydrate dissociation. Drilling fluids that are absorbed into the hydrate formation result in fast dissociation at the initial stage. As time elapses, the hydrate dissociation slows down, but the risk of wellbore instability is aggravated due to the prolonged submersion in drilling fluids. For the sake of the stability of the wellbore in deep-water drilling through hydrate formation, the drilling fluid with low temperatures should be given priority. The drilling process should be kept under balanced pressures, and the drilling time should be shortened.

Hydrogeochemistry of groundwaters in and below the base of thick permafrost at Lupin, Nunavut, Canada

NASA Astrophysics Data System (ADS)

Stotler, Randy L.; Frape, Shaun K.; Ruskeeniemi, Timo; Ahonen, Lasse; Onstott, Tullis C.; Hobbs, Monique Y.

2009-06-01

SummaryShield fluids are commonly understood to evolve through water-rock interaction. However, fluids may also concentrate during ice formation. Very little is currently known about groundwater conditions beneath thick permafrost in crystalline environments. This paper evaluates three possible Shield fluid evolution pathways at a crystalline Shield location currently under 500+ meters of permafrost, including surfical cryogenic concentration of seawater, in situ cryogenic concentration and water-rock interaction. A primary goal of this study was to further scientific understanding of permafrost and its role in influencing deep flow system evolution, fluid movement and chemical evolution of waters in crystalline rocks. Precipitation, surface, permafrost and subpermafrost water samples were collected, as well as dissolved and free gas samples, fracture fillings and matrix fluid samples to characterize the site. Investigations of groundwater conditions beneath thick permafrost provides valuable information which can be applied to safety assessment of deep, underground nuclear waste repositories, effects of long-term mining in permafrost areas and understanding analogues to potential life-bearing zones on Mars. The study was conducted in the Lupin gold mine in Nunavut, Canada, located within the zone of continuous permafrost. Through-taliks beneath large lakes in the area provided potential hydraulic connections through the permafrost. Na-Cl and Na-Cl-SO 4 type permafrost waters were contaminated by mining activities, affecting the chloride and nitrate concentrations. High nitrate concentrations (423-2630 mg L -1) were attributed to remnants of blasting. High sulfate concentrations in the permafrost (578-5000 mg L -1) were attributed to naturally occurring and mining enhanced sulfide oxidation. Mine dewatering created an artificial hydraulic gradient, resulting in methane hydrate dissociation at depth. Less contaminated basal waters had medium sulfate concentrations and were Ca-Na dominated, similar to deeper subpermafrost waters. Subpermafrost waters had a wide range of salinities (2.6-40 g L -1). It was unclear from this investigation what impact talik waters would have on deep groundwaters in undisturbed environments. In situ cryogenic concentration due to ice and methane hydrate formation may have concentrated the remaining fluids, however there was no evidence that infiltration of cryogenically concentrated seawater occurred since the last glacial maximum. Matrix waters were dilute and unable to affect groundwater salinity. Fracture infillings were scarce, but calcite fluid inclusion microthermometry indicated a large range in salinities, potentially an additional source of salinity to the system.

Effect of Hydrothermal Alteration on Rock Properties in Active Geothermal Setting

NASA Astrophysics Data System (ADS)

Mikisek, P.; Bignall, G.; Sepulveda, F.; Sass, I.

2012-04-01

Hydrothermal alteration records the physical-chemical changes of rock and mineral phases caused by the interaction of hot fluids and wall rock, which can impact effective permeability, porosity, thermal parameters, rock strength and other rock properties. In this project, an experimental approach has been used to investigate the effects of hydrothermal alteration on rock properties. A rock property database of contrastingly altered rock types and intensities has been established. The database details horizontal and vertical permeability, porosity, density, thermal conductivity and thermal heat capacity for ~300 drill core samples from wells THM12, THM13, THM14, THM17, THM18, THM22 and TH18 in the Wairakei-Tauhara geothermal system (New Zealand), which has been compared with observed hydrothermal alteration type, rank and intensity obtained from XRD analysis and optical microscopy. Samples were selected from clay-altered tuff and intercalated siltstones of the Huka Falls Formation, which acts as a cap rock at Wairakei-Tauhara, and tuffaceous sandstones of the Waiora Formation, which is a primary reservoir-hosting unit for lateral and vertical fluid flows in the geothermal system. The Huka Falls Formation exhibits argillic-type alteration of varying intensity, while underlying Waiora Formations exhibits argillic- and propylithic-type alteration. We plan to use a tempered triaxial test cell at hydrothermal temperatures (up to 200°C) and pressures typical of geothermal conditions, to simulate hot (thermal) fluid percolation through the rock matrix of an inferred "reservoir". Compressibility data will be obtained under a range of operating (simulation reservoir) conditions, in a series of multiple week to month-long experiments that will monitor change in permeability and rock strength accompanying advancing hydrothermal alteration intensity caused by the hot brine interacting with the rock matrix. We suggest, our work will provide new baseline information concerning fluid-rock interaction processes in geothermal reservoirs, and their effects on rock properties, that will aid improved understanding of the evolution of high-temperature geothermal systems, provide constraints to parameterization of reservoir models and assist future well planning and design through prediction of rock properties in the context of drilling strategies.

Partitioning of Metals Throughout a Winter Storm-Generated Fluid Mud Event, Atchafalaya Shelf, Louisiana

NASA Astrophysics Data System (ADS)

Clark, F. R.; McKee, B. A.; Duncan, D. D.

2002-12-01

Particulate and dissolved phases of a suite of metals and radionuclides were analyzed in fluid mud samples collected during a time series. This time series was taken during the passage of a winter storm on the Atchafalaya Shelf off the coast of Louisiana. The shelf receives an estimated 30% of the flow of the Mississippi River from its distributary, the Atchafalaya River. This input contributes a high sediment load to the shelf. Frequent winter storms provide shear stress to resuspend sediments and form fluid mud. Samples of fluid mud and overlying water were collected every two hours for 56 hours. Meteorological data as well as turbidity measurements by OBS were collected throughout the study. Bottom sediments were also collected before and after the time series. Partitioning effects were investigated on Be7, Th234, and Pb210 by gamma spectroscopy. These effects were also studied on several redox-sensitive metals, including Fe, Mn, Mo, Te, Re, U, Al, Ti, and V by ICP-MS analysis. Preliminary results indicate a rapid establishment of reducing conditions in fluid mud immediately overlying the seabed. These conditions persist until the suspended sediments in the fluid mud settle, and the fluid mud dissipates. The recurrence of storm front passages and their subsequent fluid mud formation cause repeated cycling from oxic to suboxic conditions in these coastal bottom waters. This redox cycling could potentially alter the fates of redox-sensitive metals, especially those associated with metal oxide carrier phases.

Competition between reaction-induced expansion and creep compaction during gypsum formation: Experimental and numerical investigation

NASA Astrophysics Data System (ADS)

Skarbek, R. M.; Savage, H. M.; Spiegelman, M. W.; Kelemen, P. B.; Yancopoulos, D.

2017-12-01

Deformation and cracking caused by reaction-driven volume increase is an important process in many geological settings, however the conditions controlling these processes are poorly understood. The interaction of rocks with reactive fluids can change permeability and reactive surface area, leading to a large variety of feedbacks. Gypsum is an ideal material to study these processes. It forms rapidly at room temperature via bassanite hydration, and is commonly used as an analogue for rocks in high-temperature, high-pressure conditions. We conducted uniaxial strain experiments to study the effects of applied axial load on deformation and fluid flow during the formation of gypsum from bassanite. While hydration of bassanite to gypsum involves a solid volume increase, gypsum exhibits significant creep compaction when in contact with water. These two volume changing processes occur simultaneously during fluid flow through bassanite. We cold-pressed bassanite powder to form cylinders 2.5 cm in height and 1.2 cm in diameter. Samples were compressed with a static axial load of 0.01 to 4 MPa. Water infiltrated initially unsaturated samples through the bottom face and the height of the samples was recorded as a measure of the total volume change. We also performed experiments on pure gypsum samples to constrain the amount of creep observed in tests on bassanite hydration. At axial loads < 0.15 MPa, volume increase due to the reaction dominates and samples exhibit monotonic expansion. At loads > 1 MPa, creep in the gypsum dominates and samples exhibit monotonic compaction. At intermediate loads, samples exhibit alternating phases of compaction and expansion due to the interplay of the two volume changing processes. We observed a change from net compaction to net expansion at an axial load of 0.250 MPa. We explain this behavior with a simple model that predicts the strain evolution, but does not take fluid flow into account. We also implement a 1D poro-visco-elastic model of the imbibition process that includes the reaction and gypsum creep. We use the results of these models, with models of the creep rate in gypsum, to estimate the temperature dependence of the axial load where total strain transitions from compaction to expansion. Our results have implications for the depth dependence of reaction induced volume changes in the Earth.

The European FP7 ULTimateCO2 project: A comprehensive approach to study the long term fate of CO2 geological storage sites

NASA Astrophysics Data System (ADS)

Audigane, P.; Brown, S.; Dimier, A.; Pearce, J.; Frykman, P.; Maurand, N.; Le Gallo, Y.; Spiers, C. J.; Cremer, H.; Rutters, H.; Yalamas, T.

2013-12-01

The European FP7 ULTimateCO2 project aims at significantly advance our knowledge of specific processes that could influence the long-term fate of geologically stored CO2: i) trapping mechanisms, ii) fluid-rock interactions and effects on mechanical integrity of fractured caprock and faulted systems and iii) leakage due to mechanical and chemical damage in the well vicinity, iv) brine displacement and fluid mixing at regional scale. A realistic framework is ensured through collaboration with two demonstration sites in deep saline sandstone formations: the onshore former NER300 West Lorraine candidate in France (ArcelorMittal GeoLorraine) and the offshore EEPR Don Valley (former Hatfield) site in UK operated by National Grid. Static earth models have been generated at reservoir and basin scale to evaluate both trapping mechanisms and fluid displacement at short (injection) and long (post injection) time scales. Geochemical trapping and reservoir behaviour is addressed through experimental approaches using sandstone core materials in batch reactive mode with CO2 and impurities at reservoir pressure and temperature conditions and through geochemical simulations. Collection of data has been generated from natural and industrial (oil industry) analogues on the fluid flow and mechanical properties, structure, and mineralogy of faults and fractures that could affect the long-term storage capacity of underground CO2 storage sites. Three inter-related lines of laboratory experiments investigate the long-term evolution of the mechanical properties and sealing integrity of fractured and faulted caprocks using Opalinus clay of Mont Terri Gallery (Switzerland) (OPA), an analogue for caprock well investigated in the past for nuclear waste disposal purpose: - Characterization of elastic parameters in intact samples by measuring strain during an axial experiment, - A recording of hydraulic fracture flow properties by loading and shearing samples in order to create a 'realistic' fracture, followed by a gas injection in the fracture plan, - An assessment of temperature influences on carbonate and water content which affect carbonate bearing fault gouge using shear experiments at 20C and 120C on simulated fault gouges prepared by crushed OPA samples. To evaluate the interactions between CO2 (and formation fluids) and the well environment (formation, cement, casing) and to assess the consequences of these interactions on the transport properties of well materials, a 1:1 scale experiment has been set in the OPA to reproduce classical well objects (cemented annulus, casing and cement plug) perforating caprock formations (OPA). Innovative probabilistic modelling tools are also under development in order to build robust calibration methods for uncertainty management of the simulated long term scenarios.

25 CFR 226.32 - Well records and reports.

Code of Federal Regulations, 2010 CFR

2010-04-01

... LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.32 Well records and reports. (a) Lessee shall... and character of oil, gas, or water in each formation, and the kind, weight, size, landed depth and... pressure or fluid sample surveys, temperature surveys, directional surveys, and the like; the materials and...

Environmental baseline conditions for impact assessment of unconventional gas exploitation: the G-Baseline project

NASA Astrophysics Data System (ADS)

Kloppmann, Wolfram; Mayer, Berhard; Millot, Romain; Parker, Beth L.; Gaucher, Eric; Clarkson, Christopher R.; Cherry, John A.; Humez, Pauline; Cahill, Aaron

2015-04-01

A major scientific challenge and an indispensible prerequisite for environmental impact assessment in the context of unconventional gas development is the determination of the baseline conditions against which potential environmental impacts on shallow freshwater resources can be accurately and quantitatively tested. Groundwater and surface water resources overlying the low-permeability hydrocarbon host rocks containing shale gas may be impacted to different extents by naturally occurring saline fluids and by natural gas emanations. Baseline assessments in areas of previous conventional hydrocarbon production may also reveal anthropogenic impacts from these activities not related to unconventional gas development. Once unconventional gas exploitation has started, the baseline may be irrevocably lost by the intricate superposition of geogenic and potential anthropogenic contamination by stray gas, formation waters and chemicals used during hydraulic fracturing. The objective of the Franco-Canadian NSERC-ANR project G-Baseline is to develop an innovative and comprehensive methodology of geochemical and isotopic characterization of the environmental baseline for water and gas samples from all three essential zones: (1) the production zone, including flowback waters, (2) the intermediate zone comprised of overlying formations, and (3) shallow aquifers and surface water systems where contamination may result from diverse natural or human impacts. The outcome will be the establishment of a methodology based on innovative tracer and monitoring techniques, including traditional and non-traditional isotopes (C, H, O, S, B, Sr, Cl, Br, N, U, Li, Cu, Zn, CSIA...) for detecting, quantifying and modeling of potential leakage of stray gas and of saline formation water mixed with flowback fluids into fresh groundwater resources and surface waters taking into account the pathways and mechanisms of fluid and gas migration. Here we present an outline of the project as well as first results from chemical and isotopic analyses on gas, fluid and solid samples collected during a baseline monitoring program at the Carbon Management Canada field research site in south-eastern Alberta, Canada.

Molten salt as a heat transfer fluid for heating a subsurface formation

DOEpatents

Nguyen, Scott Vinh; Vinegar, Harold J.

2010-11-16

A heating system for a subsurface formation includes a conduit located in an opening in the subsurface formation. An insulated conductor is located in the conduit. A material is in the conduit between a portion of the insulated conductor and a portion of the conduit. The material may be a salt. The material is a fluid at operating temperature of the heating system. Heat transfers from the insulated conductor to the fluid, from the fluid to the conduit, and from the conduit to the subsurface formation.

Particle Formation and Product Formulation Using Supercritical Fluids.

PubMed

Knez, Željko; Knez Hrnčič, Maša; Škerget, Mojca

2015-01-01

Traditional methods for solids processing involve either high temperatures, necessary for melting or viscosity reduction, or hazardous organic solvents. Owing to the negative impact of the solvents on the environment, especially on living organisms, intensive research has focused on new, sustainable methods for the processing of these substances. Applying supercritical fluids for particle formation may produce powders and composites with special characteristics. Several processes for formation and design of solid particles using dense gases have been studied intensively. The unique thermodynamic and fluid-dynamic properties of supercritical fluids can be used also for impregnation of solid particles or for the formation of solid powderous emulsions and particle coating, e.g., for formation of solids with unique properties for use in different applications. We give an overview of the application of sub- and supercritical fluids as green processing media for particle formation processes and present recent advances and trends in development.

Exploring matrix effects and quantifying organic additives in hydraulic fracturing associated fluids using liquid chromatography electrospray ionization mass spectrometry.

PubMed

Nell, Marika; Helbling, Damian E

2018-05-23

Hydraulic fracturing (HF) operations utilize millions of gallons of water amended with chemical additives including biocides, corrosion inhibitors, and surfactants. Fluids injected into the subsurface return to the surface as wastewaters, which contain a complex mixture of additives, transformation products, and geogenic chemical constituents. Quantitative analytical methods are needed to evaluate wastewater disposal alternatives or to conduct adequate exposure assessments. However, our narrow understanding of how matrix effects change the ionization efficiency of target analytes limits the quantitative analysis of polar to semi-polar HF additives by means of liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). To address this limitation, we explored the ways in which matrix chemistry influences the ionization of seventeen priority HF additives with a modified standard addition approach. We then used the data to quantify HF additives in HF-associated fluids. Our results demonstrate that HF additives generally exhibit suppressed ionization in HF-associated fluids, though HF additives that predominantly form sodiated adducts exhibit significantly enhanced ionization in produced water samples, which is largely the result of adduct shifting. In a preliminary screening, we identified glutaraldehyde and 2-butoxyethanol along with homologues of benzalkonium chloride (ADBAC), polyethylene glycol (PEG), and polypropylene glycol (PPG) in HF-associated fluids. We then used matrix recovery factors to provide the first quantitative measurements of individual homologues of ADBAC, PEG, and PPG in HF-associated fluids ranging from mg L-1 levels in hydraulic fracturing fluid to low μg L-1 levels in PW samples. Our approach is generalizable across sample types and shale formations and yields important data to evaluate wastewater disposal alternatives or implement exposure assessments.

Investigating the Influence of Magmatic Volatile Input and Seawater Entrainment on Vent Deposit Morphology and Composition in Manus Basin (Back-arc) Hydrothermal Systems

NASA Astrophysics Data System (ADS)

Tivey, M.; Bach, W.; Tivey, M.; Seewald, J.; Craddock, P.; Rouxel, O.; Yoerger, D.; Yeats, C.; McConachy, T.; Quigley, M.; Vanko, D.

2006-12-01

In August 2006, hydrothermal activity within the eastern Manus Basin north of Papua New Guinea was investigated using a combination of mapping (SeaBeam from the R/V Melville, near-bottom multi-beam sonar and magnetometer from AUV ABE and ROV Jason-2) and sampling (fluids and solids using ROV Jason-2). Objectives included identifying tectonic/geologic settings, examining interactions of seawater with felsic rocks that constitute the high silica end-member in the range of basement compositions, determining the extent of volatile magmatic inputs into these systems, and examining the evolution of hydrothermal activity through time. At the PACMANUS (Papua New Guinea Australia Canada Manus) area five previously discovered vent fields were mapped and sampled, and a new very active field, Fenway, was located south of the Satanic Mills field. The core of the Fenway field is a 40 m diameter two-tiered mound. A large black smoker complex venting boiling (356C, 172 bar) fluids forms the upper tier, with the lower tier composed of sulfide debris, massive anhydrite-sulfide deposits, and anhydrite sand. At the DESMOS Caldera hyaloclastites and extensive patches of bleached and stained substrate were mapped and sampled, as were diffuse (72C) and focused (119C) acidic fluids with a pH (25C) of 1.0; no sulfide deposits were observed in the area. At the North Su vent field within the SuSu Knolls area even lower pH fluids were sampled (see Seewald et al., this session). Hydrothermal activity includes venting of white sulfur-rich fluids through cracks and sediments, formation of native sulfur flanges, diffuse venting through spires, and black smoker activity (324C). Anhydrite cement is also present. The abundance of massive anhydrite at Fenway and presence of anhydrite cement at North Su is consistent with significant local entrainment and heating of seawater. The extremely low pH (less than 2) of some vent fluids supports previous hypotheses that fluids in this area contain significant input of magmatic volatiles (e.g., Gamo et al. 1997, Geology 25). During the cruise, 104 black, gray, and clear fluids were sampled using gas-tight and major samplers, and 198 vent sulfide deposit, 83 altered substrate, and 43 fresh lava samples were recovered. Geophysical maps and geochemical data for solids and fluids will be used to determine the styles of mixing and reaction occurring beneath the vent fields, estimate subsurface mineral deposition, and investigate the extent to which input of magmatic fluids is occurring within each system.

Organic and inorganic composition and microbiology of produced waters from Pennsylvania shale gas wells

USGS Publications Warehouse

Akob, Denise M.; Cozzarelli, Isabelle M.; Dunlap, Darren S.; Rowan, Elisabeth L.; Lorah, Michelle M.

2015-01-01

Hydraulically fractured shales are becoming an increasingly important source of natural gas production in the United States. This process has been known to create up to 420 gallons of produced water (PW) per day, but the volume varies depending on the formation, and the characteristics of individual hydraulic fracture. PW from hydraulic fracturing of shales are comprised of injected fracturing fluids and natural formation waters in proportions that change over time. Across the state of Pennsylvania, shale gas production is booming; therefore, it is important to assess the variability in PW chemistry and microbiology across this geographical span. We quantified the inorganic and organic chemical composition and microbial communities in PW samples from 13 shale gas wells in north central Pennsylvania. Microbial abundance was generally low (66–9400 cells/mL). Non-volatile dissolved organic carbon (NVDOC) was high (7–31 mg/L) relative to typical shallow groundwater, and the presence of organic acid anions (e.g., acetate, formate, and pyruvate) indicated microbial activity. Volatile organic compounds (VOCs) were detected in four samples (∼1 to 11.7 μg/L): benzene and toluene in the Burket sample, toluene in two Marcellus samples, and tetrachloroethylene (PCE) in one Marcellus sample. VOCs can be either naturally occurring or from industrial activity, making the source of VOCs unclear. Despite the addition of biocides during hydraulic fracturing, H2S-producing, fermenting, and methanogenic bacteria were cultured from PW samples. The presence of culturable bacteria was not associated with salinity or location; although organic compound concentrations and time in production were correlated with microbial activity. Interestingly, we found that unlike the inorganic chemistry, PW organic chemistry and microbial viability were highly variable across the 13 wells sampled, which can have important implications for the reuse and handling of these fluids

Microbial communities at the borehole observatory on the Costa Rica Rift flank (Ocean Drilling Program Hole 896A).

PubMed

Nigro, Lisa M; Harris, Kate; Orcutt, Beth N; Hyde, Andrew; Clayton-Luce, Samuel; Becker, Keir; Teske, Andreas

2012-01-01

The microbiology of subsurface, hydrothermally influenced basaltic crust flanking mid-ocean ridges has remained understudied, due to the difficulty in accessing the subsurface environment. The instrumented boreholes resulting from scientific ocean drilling offer access to samples of the formation fluids circulating through oceanic crust. We analyzed the phylogenetic diversity of bacterial communities of fluid and microbial mat samples collected in situ from the observatory at Ocean Drilling Program Hole 896A, drilled into ~6.5 million-year-old basaltic crust on the flank of the Costa Rica Rift in the equatorial Pacific Ocean. Bacterial 16S rRNA gene sequences recovered from borehole fluid and from a microbial mat coating the outer surface of the fluid port revealed both unique and shared phylotypes. The dominant bacterial clones from both samples were related to the autotrophic, sulfur-oxidizing genus Thiomicrospira. Both samples yielded diverse gamma- and alphaproteobacterial phylotypes, as well as members of the Bacteroidetes, Planctomycetes, and Verrucomicrobia. Analysis of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) genes (cbbL and cbbM) from the sampling port mat and from the borehole fluid demonstrated autotrophic carbon assimilation potential for in situ microbial communities; most cbbL genes were related to those of the sulfur-oxidizing genera Thioalkalivibrio and Thiomicrospira, and cbbM genes were affiliated with uncultured phylotypes from hydrothermal vent plumes and marine sediments. Several 16S rRNA gene phylotypes from the 896A observatory grouped with phylotypes recovered from seawater-exposed basalts and sulfide deposits at inactive hydrothermal vents, but there is little overlap with hydrothermally influenced basaltic boreholes 1026B and U1301A on the Juan de Fuca Ridge flank, suggesting that site-specific characteristics of Hole 896A (i.e., seawater mixing into borehole fluids) affect the microbial community composition.

Tracing fluid transfer across subduction zones using iron and zinc stable isotopes

NASA Astrophysics Data System (ADS)

Williams, H. M.; Debret, B.; Pons, M. L.; Bouilhol, P.

2016-12-01

In subduction zones, serpentinite devolatilization within the downgoing slab and the fluids released play a fundamental role in volatile transfer as well as the redox evolution of the sub-arc mantle. Constraining subduction-related serpentinite devolatilisation is essential in order to better understand of the nature and composition of slab-derived fluids and fluid/rock interactions. Fe and Zn stable isotopes can trace fluid composition and speciation as isotope partitioning is driven by changes in oxidation state, coordination, and bonding environment. In the case of serpentinite devolatilisation, Fe isotope fractionation should reflect changes in Fe redox state and the formation of Fe-Cl- and SO42- complexes (Hill et al., GCA 2010); Zn isotope fractionation should be sensitive to complexation with CO32-, HS- and SO42- anions (Fujii et al., GCA 2011). We targeted samples from Western Alps ophiolite complexes, interpreted as remnants of serpentinized oceanic lithosphere metamorphosed and devolatilized during subduction (Hattori and Guillot, G3 2007; Debret et al., Chem. Geol. 2013). A striking negative correlation is present between bulk serpentinite Fe isotope composition and Fe3+/Fetot, with the highest grade samples displaying the heaviest Fe isotope compositions and lowest Fe3+/Fetot (Debret et al., Geology, 2016). The same samples also display a corresponding variation in Zn isotopes, with the highest grade samples displaying isotopically light compositions (Pons et al., in revision). The negative correlation between Fe and Zn isotopes and decrease in Fe3+/Fetot can explained by serpentinite sulfide breakdown and the release of fluids enriched in isotopically light Fe and heavy Zn sulphate complexes. The migration of these SOX-bearing fluids from the slab to the slab-mantle interface or mantle wedge has important implications for the redox evolution of the sub-arc mantle and the transport of metals from the subducting slab.

Hydrogeology, chemical and microbial activity measurement through deep permafrost

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stotler, R.L.; Frape, S.K.; Freifeld, B.M.

2010-04-01

Little is known about hydrogeochemical conditions beneath thick permafrost, particularly in fractured crystalline rock, due to difficulty in accessing this environment. The purpose of this investigation was to develop methods to obtain physical, chemical, and microbial information about the subpermafrost environment from a surface-drilled borehole. Using a U-tube, gas and water samples were collected, along with temperature, pressure, and hydraulic conductivity measurements, 420 m below ground surface, within a 535 m long, angled borehole at High Lake, Nunavut, Canada, in an area with 460-m-thick permafrost. Piezometric head was well above the base of the permafrost, near land surface. Initial watermore » samples were contaminated with drill fluid, with later samples <40% drill fluid. The salinity of the non-drill fluid component was <20,000 mg/L, had a Ca/Na ratio above 1, with {delta}{sup 18}O values {approx}5{per_thousand} lower than the local surface water. The fluid isotopic composition was affected by the permafrost-formation process. Nonbacteriogenic CH{sub 4} was present and the sample location was within methane hydrate stability field. Sampling lines froze before uncontaminated samples from the subpermafrost environment could be obtained, yet the available time to obtain water samples was extended compared to previous studies. Temperature measurements collected from a distributed temperature sensor indicated that this issue can be overcome easily in the future. The lack of methanogenic CH{sub 4} is consistent with the high sulfate concentrations observed in cores. The combined surface-drilled borehole/U-tube approach can provide a large amount of physical, chemical, and microbial data from the subpermafrost environment with few, controllable, sources of contamination.« less

Hydrogeology, Chemical and Microbial Activity Measurement Through Deep Permafrost

USGS Publications Warehouse

Stotler, R.L.; Frape, S.K.; Freifeld, B.M.; Holden, B.; Onstott, T.C.; Ruskeeniemi, T.; Chan, E.

2011-01-01

Little is known about hydrogeochemical conditions beneath thick permafrost, particularly in fractured crystalline rock, due to difficulty in accessing this environment. The purpose of this investigation was to develop methods to obtain physical, chemical, and microbial information about the subpermafrost environment from a surface-drilled borehole. Using a U-tube, gas and water samples were collected, along with temperature, pressure, and hydraulic conductivity measurements, 420 m below ground surface, within a 535 m long, angled borehole at High Lake, Nunavut, Canada, in an area with 460-m-thick permafrost. Piezometric head was well above the base of the permafrost, near land surface. Initial water samples were contaminated with drill fluid, with later samples <40% drill fluid. The salinity of the non-drill fluid component was <20,000 mg/L, had a Ca/Na ratio above 1, with ??18O values ???5??? lower than the local surface water. The fluid isotopic composition was affected by the permafrost-formation process. Nonbacteriogenic CH4 was present and the sample location was within methane hydrate stability field. Sampling lines froze before uncontaminated samples from the subpermafrost environment could be obtained, yet the available time to obtain water samples was extended compared to previous studies. Temperature measurements collected from a distributed temperature sensor indicated that this issue can be overcome easily in the future. The lack of methanogenic CH4 is consistent with the high sulfate concentrations observed in cores. The combined surface-drilled borehole/U-tube approach can provide a large amount of physical, chemical, and microbial data from the subpermafrost environment with few, controllable, sources of contamination. ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

ATimer-Actuated, Immunoassay Cassette for Detecting Molecular Markers in Oral Fluids

PubMed Central

Liu, Changchun; Qiu, Xianbo; Ongagna, Serge; Chen, Dafeng; Chen, Zongyuan; Abrams, William R.; Malamud, Daniel; Corstjens, Paul L.A.M.; Bau, Haim H.

2009-01-01

An inexpensive, hand-held, point-of-care, disposable, self-contained, immunoassay cassette comprised of air pouches for pumping, a metering chamber, reagents storage chambers, a mixer, and a lateral flow strip was designed, constructed, and tested. The assay was carried out in a consecutive flow format. The detection was facilitated with up-converting, phosphor (UCP) reporter particles. The automated, timely pumping of the various reagents was driven by a spring-loaded timer. The utility of the cassette was demonstrated by detecting antibodies to HIV in saliva samples and further evaluated with a non-contagious, haptenized DNA assay. The cassette has several advantages over dip sticks such as sample preprocessing, integrated storage of reagents, and automated operation that reduces operator errors and training. The cassette and actuator described herein can readily be extended to detect biomarkers of other diseases in body fluids and other fluids at the point of care. The system is particularly suitable for resource poor countries, where funds and trained personnel are in short supply. PMID:19255658

Phospholipid transfer protein is present in human tear fluid.

PubMed

Jauhiainen, Matti; Setälä, Niko L; Ehnholm, Christian; Metso, Jari; Tervo, Timo M T; Eriksson, Ove; Holopainen, Juha M

2005-06-07

The human tear fluid film consists of a superficial lipid layer, an aqueous middle layer, and a hydrated mucin layer located next to the corneal epithelium. The superficial lipid layer protects the eye from drying and is composed of polar and neutral lipids provided by the meibomian glands. Excess accumulation of lipids in the tear film may lead to drying of the corneal epithelium. In the circulation, phospholipid transfer protein (PLTP) and cholesteryl ester transfer protein (CETP) mediate lipid transfers. To gain insight into the formation of tear film, we investigated whether PLTP and CETP are present in human tear fluid. Tear fluid samples were collected with microcapillaries. The presence of PLTP and CETP was studied in tear fluid by Western blotting, and the PLTP concentration was determined by ELISA. The activities of the enzymes were determined by specific lipid transfer assays. Size-exclusion and heparin-affinity chromatography assessed the molecular form of PLTP. PLTP is present in tear fluid, whereas CETP is not. Quantitative assessment of PLTP by ELISA indicated that the PLTP concentration in tear fluid, 10.9 +/- 2.4 microg/mL, is about 2-fold higher than that in human plasma. PLTP-facilitated phospholipid transfer activity in tears, 15.1 +/- 1.8 micromol mL(-)(1) h(-)(1), was also significantly higher than that measured in plasma. Inactivation of PLTP by heat treatment (+58 degrees C, 60 min) or immunoinhibition abolished the phospholipid transfer activity in tear fluid. Size-exclusion chromatography of tear fluid indicated that PLTP eluted in a position corresponding to a size of 160-170 kDa. Tear fluid PLTP was quantitatively bound to Heparin-Sepharose and could be eluted as a single peak by 0.5 M NaCl. These data indicate that human tear fluid contains catalytically active PLTP protein, which resembles the active form of PLTP present in plasma. The results suggest that PLTP may play a role in the formation of the tear film by supporting phospholipid transfer.

CALCIPROTEIN PARTICLE FORMATION IN PERITONEAL DIALYSIS EFFLUENT IS DEPENDENT ON DIALYSATE CALCIUM CONCENTRATION.

PubMed

Cai, Michael M; Smith, Edward R; Kent, Annette; Huang, Louis; Hewitson, Tim D; McMahon, Lawrence P; Holt, Stephen G

2018-05-23

The accumulation of fetuin-A-containing calciprotein particles (CPP) in the serum of patients with renal disease and those with chronic inflammation may be involved in driving sterile inflammation and extraosseous mineral deposition. We previously showed that both fetuin-A and CPP were present in the peritoneal dialysis (PD) effluent of stable PD patients. It is unknown whether different PD fluids might affect the formation of CPP in vivo Method: Peritoneal effluent from 12 patients was collected after a 6-hour dwell with 7 different commercial PD fluids. Calciprotein particles and inflammatory cytokines were measured by flow cytometry. High inter-subject variability in CPP concentration was observed. Peritoneal dialysis fluids containing 1.75 mmol/L calcium were associated with enhanced formation of CPP in vivo , compared with fluids containing 1.25 mmol/L calcium. Osmotic agent, fluid pH, and glucose concentration did not affect CPP formation. Peritoneal dialysis effluent CPP levels were not associated with changes in inflammatory cytokines. High calcium-containing PD fluids favor intraperitoneal CPP formation. This finding may have relevance for future PD fluid design.

Fine-grained Goethite as a Precursor for Martian Gray Hematite

NASA Technical Reports Server (NTRS)

Glotch, T. D.; Morris, R. V.; Sharp, T. G.; Christensen, P. R.

2003-01-01

Several isolated deposits of gray, crystalline hematite on Mars were discovered using data returned from the Thermal Emission Spectrometer (TES) instrument aboard the Mars Global Surveyor spacecraft. Christensen et al. provided five testable hypotheses regarding the formation of crystalline hematite on Mars: 1) low-temperature precipitation of Fe oxides/hydroxides from standing, oxygenated, Fe-rich water, followed by subsequent alteration to gray hematite, 2) low-temperature leaching of iron-bearing silicates and other materials leaving a Fe-rich residue laterite-style weathering) which is subsequently altered to gray hematite, 3) direct precipitation of gray hematite from Fe-rich circulating fluids of hydrothermal or other origin, 4) formation of gray hematitic surface coatings during weathering, and 5) thermal oxidation of magnetite-rich lavas. Since this initial work, several authors have examined the hematite deposits to determine their formation mechanism. Lane et al. cited the absence of a 390/ cm absorption in the martian hematite spectrum as evidence for platy hematite grains. Their model for the formation of the deposits includes deposition of any of a variety of iron oxides or oxyhydroxides by aqueous or hydrothermal fluids, burial and metamorphosis to gray platy hematite grains, and exhumation in recent times. Based on a detailed geomorphic examination of the Sinus Meridiani region, Hynek et al. conclude that the most likely method of hematite formation was either emplacement by a hydrothermal fluid or oxidation of a magnetite-rich pyroclastic deposit. Similarly, Arvidson et al., favor a model involving the alteration of pyroclastic deposits by aqueous or hydrothermal fluids. Finally, based on geochemical modeling and an examination of Aram Chaos, Catling and Moore favor emplacement by hydrothermal fluids with a minimum temperature of 100 C. Comparison of the average martian hematite spectrum measured by TES to hematite emissivity spectra for a variety of naturally occurring hematites shows small but potentially important differences. In particular, band shapes, positions and relative band emissivities of hematite spectra vary over the range of samples. These differences imply that the natural variability of thermal infrared hematite spectra has not been fully characterized, especially with respect to the reaction pathway and crystal structure.

Method of producing drive fluid in situ in tar sands formations

DOEpatents

Mudunuri, Ramesh Raju; Jaiswal, Namit; Vinegar, Harold J.; Karanikas, John Michael

2010-03-23

Methods of treating a tar sands formation are described herein. Methods for treating a tar sands may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. The heat may be allowed to transfer from the heaters to at least a portion of the formation such that a drive fluid is produced in situ in the formation. The drive fluid may move at least some mobilized, visbroken, and/or pyrolyzed hydrocarbons from a first portion of the formation to a second portion of the formation. At least some of the mobilized, visbroken, and/or pyrolyzed hydrocarbons may be produced from the formation.

Recirculation System for Geothermal Energy Recovery in Sedimentary Formations: Laboratory Experiments and Numerical Simulations

NASA Astrophysics Data System (ADS)

Elkhoury, J. E.; Detwiler, R. L.; Serajian, V.; Bruno, M. S.

2012-12-01

Geothermal energy resources are more widespread than previously thought and have the potential for providing a significant amount of sustainable clean energy worldwide. In particular, hot permeable sedimentary formations provide many advantages over traditional geothermal recovery and enhanced geothermal systems in low permeability crystalline formations. These include: (1) eliminating the need for hydraulic fracturing, (2) significant reduction in risk for induced seismicity, (3) reducing the need for surface wastewater disposal, (4) contributing to decreases in greenhouse gases, and (5) potential use for CO2 sequestration. Advances in horizontal drilling, completion, and production technology from the oil and gas industry can now be applied to unlock these geothermal resources. Here, we present experimental results from a laboratory scale circulation system and numerical simulations aimed at quantifying the heat transfer capacity of sedimentary rocks. Our experiments consist of fluid flow through a saturated and pressurized sedimentary disc of 23-cm diameter and 3.8-cm thickness heated along its circumference at a constant temperature. Injection and production ports are 7.6-cm apart in the center of the disc. We used DI de-aired water and mineral oil as working fluids and explored temperatures from 20 to 150 oC and flow rates from 2 to 30 ml/min. We performed experiments on sandstone samples (Castlegate and Kirby) with different porosity, permeability and thermal conductivity to evaluate the effect of hydraulic and thermal properties on the heat transfer capacity of sediments. The producing fluid temperature followed an exponential form with time scale transients between 15 and 45 min. Steady state outflow temperatures varied between 60% and 95% of the set boundary temperature, higher percentages were observed for lower temperatures and flow rates. We used the flow and heat transport simulator TOUGH2 to develop a numerical model of our laboratory setting. Given the remarkable match between our observations and numerical results, we extended our model to explore a wider range of thermal and hydrological parameters beyond the experimental conditions. Our results prove the capability of heat transfer in sedimentary formations for geothermal energy production.) Sandstone sample with two thermally insulating Teflon caps (white discs). In and out arrows indicate the flow direction while the sample is heated along its circumference (heater not shown). B) Example of a 2D temperature distribution during injection. White x shows the location of the flow ports, inlet (left) and outlet (right). Red is the set boundary temperature and blue is the fluid temperature at the inlet.

Methods for forming wellbores in heated formations

DOEpatents

Guimerans, Rosalvina Ramona; Mansure, Arthur James

2012-09-25

A method for forming a wellbore in a heated formation includes flowing liquid cooling fluid to a bottom hole assembly in a wellbore in a heated formation. At least a portion of the liquid cooling fluid is vaporized at or near a region to be cooled. Vaporizing the liquid cooling fluid absorbs heat from the region to be cooled.

Fluid source inferred from strontium isotopes in pore fluid and carbonate recovered during Expedition 337 off Shimokita, Japan

NASA Astrophysics Data System (ADS)

Hong, W.; Moen, N.; Haley, B. A.

2013-12-01

IODP Expedition 337 was designed to understand the relationship between a deep-buried (2000 meters below seafloor) hydrocarbon reservoir off the Shimokita peninsula (Japan), and the microbial community that this carbon reservoir sustains at such depth. Understanding sources and pathways of flow of fluids that carry hydrocarbons, nutrients, and other reduced components is of particular interest to fulfilling the expedition objectives, since this migrating fluid supports microbial activity not only of the deep-seated communities but also to the shallow-dwelling organisms. To this aim, the concentration and isotopic signature of Sr can be valuable due to that it is relatively free from biogenic influence and pristine in terms of drill fluid contamination. From the pore water Sr profile, concentration gradually increases from 1500 to 2400 mbsf. The depth where highest Sr concentration is observed corresponds to the depths where couple layers of carbonate were observed. Such profile suggests an upward-migrating fluid carries Sr from those deep-seated carbonate layers (>2400 mbsf) to shallower sediments. To confirm this inference, pore water, in-situ formation fluid, and carbonate samples were analyzed for Sr isotopes to investigate the fluid source.

Prograde infiltration of Cl-rich fluid into the granulitic continental crust from a collision zone in East Antarctica (Perlebandet, Sør Rondane Mountains)

NASA Astrophysics Data System (ADS)

Kawakami, Tetsuo; Higashino, Fumiko; Skrzypek, Etienne; Satish-Kumar, M.; Grantham, Geoffrey; Tsuchiya, Noriyoshi; Ishikawa, Masahiro; Sakata, Shuhei; Hirata, Takafumi

2017-03-01

Utilizing microstructures of Cl-bearing biotite in pelitic and felsic metamorphic rocks, the timing of Cl-rich fluid infiltration is correlated with the pressure-temperature-time (P-T-t) path of upper amphibolite- to granulite-facies metamorphic rocks from Perlebandet, Sør Rondane Mountains (SRM), East Antarctica. Microstructural observation indicates that the stable Al2SiO5 polymorph changed from sillimanite to kyanite + andalusite + sillimanite, and P-T estimates from geothermobarometry point to a counterclockwise P-T path characteristic of the SW terrane of the SRM. In situ laser ablation inductively coupled plasma mass spectrometry for U-Pb dating of zircon inclusions in garnet yielded ca. 580 Ma, likely representing the age of garnet-forming metamorphism at Perlebandet. Inclusion-host relationships among garnet, sillimanite, and Cl-rich biotite (Cl > 0.4 wt%) reveal that formation of Cl-rich biotite took place during prograde metamorphism in the sillimanite stability field. This process probably predated partial melting consuming biotite (Cl = 0.1-0.3 wt%). This was followed by retrograde, moderately Cl-bearing biotite (Cl = 0.1-0.3 wt%) replacing garnet. Similar timings of Cl-rich biotite formation in different samples, and similar f(H2O)/f(HCl) values of coexisting fluid estimated for each stage can be best explained by prograde Cl-rich fluid infiltration. Fluid-present partial melting at the onset of prograde metamorphism probably contributed to elevate the Cl concentration (and possibly salinity) of the fluid, and consumption of the fluid resulted in the progress of dehydration melting. The retrograde fluid was released from crystallizing Cl-bearing partial melts or derived externally. The prograde Cl-rich fluid infiltration in Perlebandet presumably took place at the uppermost part of the footwall of the collision boundary. Localized distribution of Cl-rich biotite and hornblende along large-scale shear zones and detachments in the SRM supports external input of Cl-rich fluids through tectonic boundaries during continental collision.

Precipitation and growth of barite within hydrothermal vent deposits from the Endeavour Segment, Juan de Fuca Ridge

NASA Astrophysics Data System (ADS)

Jamieson, John William; Hannington, Mark D.; Tivey, Margaret K.; Hansteen, Thor; Williamson, Nicole M.-B.; Stewart, Margaret; Fietzke, Jan; Butterfield, David; Frische, Matthias; Allen, Leigh; Cousens, Brian; Langer, Julia

2016-01-01

Hydrothermal vent deposits form on the seafloor as a result of cooling and mixing of hot hydrothermal fluids with cold seawater. Amongst the major sulfide and sulfate minerals that are preserved at vent sites, barite (BaSO4) is unique because it requires the direct mixing of Ba-rich hydrothermal fluid with sulfate-rich seawater in order for precipitation to occur. Because of its extremely low solubility, barite crystals preserve geochemical fingerprints associated with conditions of formation. Here, we present data from petrographic and geochemical analyses of hydrothermal barite from the Endeavour Segment of the Juan de Fuca Ridge, northeast Pacific Ocean, in order to determine the physical and chemical conditions under which barite precipitates within seafloor hydrothermal vent systems. Petrographic analyses of 22 barite-rich samples show a range of barite crystal morphologies: dendritic and acicular barite forms near the exterior vent walls, whereas larger bladed and tabular crystals occur within the interior of chimneys. A two component mixing model based on Sr concentrations and 87Sr/86Sr of both seawater and hydrothermal fluid, combined with 87Sr/86Sr data from whole rock and laser-ablation ICP-MS analyses of barite crystals indicate that barite precipitates from mixtures containing as low as 17% and as high as 88% hydrothermal fluid component, relative to seawater. Geochemical modelling of the relationship between aqueous species concentrations and degree of fluid mixing indicates that Ba2+ availability is the dominant control on mineral saturation. Observations combined with model results support that dendritic barite forms from fluids of less than 40% hydrothermal component and with a saturation index greater than ∼0.6, whereas more euhedral crystals form at lower levels of supersaturation associated with greater contributions of hydrothermal fluid. Fluid inclusions within barite indicate formation temperatures of between ∼120 °C and 240 °C during barite crystallization. The comparison of fluid inclusion formation temperatures to modelled mixing temperatures indicates that conductive cooling of the vent fluid accounts for 60-120 °C reduction in fluid temperature. Strontium zonation within individual barite crystals records fluctuations in the amount of conductive cooling within chimney walls that may result from cyclical oscillations in hydrothermal fluid flux. Barite chemistry and morphology can be used as a reliable indicator for past conditions of mineralization within both extinct seafloor hydrothermal deposits and ancient land-based volcanogenic massive sulfide deposits.

Liquid microjunction surface sampling probe fluid dynamics: Characterization and application of an analyte plug formation operational mode

DOE Office of Scientific and Technical Information (OSTI.GOV)

ElNaggar, Mariam S.; Van Berkel, Gary J.

2011-08-10

The recently discovered sample plug formation and injection operational mode of a continuous flow, coaxial tube geometry, liquid microjunction surface sampling probe (LMJ-SSP) (J. Am. Soc. Mass Spectrom, 2011) was further characterized and applied for concentration and mixing of analyte extracted from multiple areas on a surface and for nanoliter-scale chemical reactions of sampled material. A transparent LMJ-SSP was constructed and colored analytes were used so that the surface sampling process, plug formation, and the chemical reactions could be visually monitored at the sampling end of the probe before being analyzed by mass spectrometry of the injected sample plug. Injectionmore » plug peak widths were consistent for plug hold times as long as the 8 minute maximum attempted (RSD below 1.5%). Furthermore, integrated injection peak signals were not significantly different for the range of hold times investigated. The ability to extract and completely mix individual samples within a fixed volume at the sampling end of the probe was demonstrated and a linear mass spectral response to the number of equivalent analyte spots sampled was observed. Lastly, using the color and mass changing chemical reduction of the redox dye 2,6-dichlorophenol-indophenol with ascorbic acid, the ability to sample, concentrate, and efficiently run reactions within the same plug volume within the probe was demonstrated.« less

Basic data report for drilling and hydrologic testing of drillhole DOE-2 at the Waste Isolation Pilot Plant (WIIP) site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mercer, J.W.; Beauheim, R.L.; Snyder, R.P.

1987-04-01

Drillhole DOE-2 was drilled to investigate a structural depression marked by the downward displacement of stratigraphic markers in the Salado Formation. Contrary to several hypotheses, halite layers were thicker in the lower part of the Salado, not thinner as a result of any removal of halite. The upper Castile anhydrite in Drillhole DOE-2 is anomalously thick and is strongly deformed relative to the anhydrite in adjacent drillholes. In contrast, the halite was <8 ft thick and significantly thinner than usually encountered. The lower Castile anhydrite appears to be normal. The depression within the correlated marker beds in the Salado Formationmore » in Drillhole DOE-2 is interpreted as a result of gravity-driven deformation of the underlying Castile Formation. Several stratigraphic units were hydrologically tested in Drillhole DOE-2. Testing of the unsaturated lower portion of the Dewey Lake Red Beds was unsuccessful because of exceptionally small rates of fluid intake. Drill-stem tests were conducted in five intervals in the Rustler Formation, over the Marker Bed 138-139 interval in the Salado formation, and over three sandstone members of the Bell Canyon Formation. A pumping test was conducted in the Culebra Dolomite Member of the Rustler Formation. Pressure-pulse tests were conducted over the entire Salado Formation. Fluid samples were collected from the Culebra Dolomite Member and from the Hays Member of the Bell Canyon Formation. 31 refs., 31 figs., 5 tabs.« less

The wavefield of acoustic logging in a cased hole with a single casing—Part II: a dipole tool

NASA Astrophysics Data System (ADS)

Wang, Hua; Fehler, Michael

2018-02-01

The acoustic method, being the most effective method for cement bond evaluation, has been used by industry for more than a half century. However, the methods currently used are almost always focused on the first arrival (especially for sonic logging), which has limitations. We use a 3-D finite-difference method to numerically simulate the wavefields from a dipole source in a single-cased hole with different cement conditions. By using wavefield snapshots and dispersion curves, we interpret the characteristics of the modes in the models. We investigate the effect of source frequency, the thickness and location of fluid columns on different modes. The dipole wavefield in a single-cased hole consists of a leaky P (for frequency >10 kHz) from formation, formation flexural, and also some casing modes. Depending on the mode, their behaviour is sometimes sensitive to the existence of fluid between the cement and formation and sometimes sensitive to the existence of fluid between the casing and cement. The formation S velocity can be obtained from the formation flexural mode at low frequency. However, interference from high-order casing modes makes the leaky P invisible and P velocity determination difficult when the casing is not well cemented. The dispersion curve of the formation flexural mode is sensitive to the fluid thickness when fluid exists only at the interface between casing and cement. The fundamental casing dipole mode is only sensitive to the total fluid thickness in the annulus between casing and formation. Either the arrival time or amplitude of the high-order casing dipole mode is sensitive to the fluid column when the fluid column is next to the casing. We provide a table that summarizes the ability of different modes to detect fluid columns between various layers of casing, cement and formation. Based on the results, we suggest a data processing flow for field application, which will highly improve cement evaluation.

Long-wave equivalent viscoelastic solids for porous rocks saturated by two-phase fluids

NASA Astrophysics Data System (ADS)

Santos, J. E.; Savioli, G. B.

2018-04-01

Seismic waves traveling across fluid-saturated poroelastic materials with mesoscopic-scale heterogeneities induce fluid flow and Biot's slow waves generating energy loss and velocity dispersion. Using Biot's equations of motion to model these type of heterogeneities would require extremely fine meshes. We propose a numerical upscaling procedure to determine the complex and frequency dependent P-wave and shear moduli of an effective viscoelastic medium long-wave equivalent to a poroelastic solid saturated by a two-phase fluid. The two-phase fluid is defined in terms of capillary pressure and relative permeability flow functions. The P-wave and shear effective moduli are determined using harmonic compressibility and shear experiments applied on representative samples of the bulk material. Each experiment is associated with a boundary value problem that is solved using the finite element method. Since a poroelastic solid saturated by a two-phase fluid supports the existence of two slow waves, this upscaling procedure allows to analyze their effect on the mesoscopic-loss mechanism in hydrocarbon reservoir formations. Numerical results show that a two-phase Biot medium model predicts higher attenuation than classic Biot models.

Long-wave equivalent viscoelastic solids for porous rocks saturated by two-phase fluids

NASA Astrophysics Data System (ADS)

Santos, J. E.; Savioli, G. B.

2018-07-01

Seismic waves travelling across fluid-saturated poroelastic materials with mesoscopic-scale heterogeneities induce fluid flow and Biot's slow waves generating energy loss and velocity dispersion. Using Biot's equations of motion to model these type of heterogeneities would require extremely fine meshes. We propose a numerical upscaling procedure to determine the complex and frequency-dependent Pwave and shear moduli of an effective viscoelastic medium long-wave equivalent to a poroelastic solid saturated by a two-phase fluid. The two-phase fluid is defined in terms of capillary pressure and relative permeability flow functions. The Pwave and shear effective moduli are determined using harmonic compressibility and shear experiments applied on representative samples of the bulk material. Each experiment is associated with a boundary value problem that is solved using the finite element method. Since a poroelastic solid saturated by a two-phase fluid supports the existence of two slow waves, this upscaling procedure allows to analyse their effect on the mesoscopic loss mechanism in hydrocarbon reservoir formations. Numerical results show that a two-phase Biot medium model predicts higher attenuation than classic Biot models.

Environmental consequences of shale gas exploitation and the crucial role of rock microfracturing

NASA Astrophysics Data System (ADS)

Renard, Francois

2015-04-01

The growing exploitation of unconventional gas and oil resources has dramatically changed the international market of hydrocarbons in the past ten years. However, several environmental concerns have also been identified such as the increased microseismicity, the leakage of gas into freshwater aquifers, and the enhanced water-rock interactions inducing the release of heavy metals and other toxic elements in the produced water. In all these processes, fluids are transported into a network of fracture, ranging from nanoscale microcracks at the interface between minerals and the kerogen of the source rock, to well-developed fractures at the meter scale. Characterizing the fracture network and the mechanisms of its formation remains a crucial goal. A major difficulty when analyzing fractures from core samples drilled at depth is that some of them are produced by the coring process, while some other are produced naturally at depth by the coupling between geochemical and mechanical forces. Here, I present new results of high resolution synchrotron 3D X-ray microtomography imaging of shale samples, at different resolutions, to characterize their microfractures and their mechanisms of formation. The heterogeneities of rock microstructure are also imaged, as they create local stress concentrations where cracks may nucleate or along which they propagate. The main results are that microcracks form preferentially along kerogen-mineral interfaces and propagate along initial heterogeneities according to the local stress direction, connecting to increase the total volume of fractured rock. Their lifetime is also an important parameter because they may seal by fluid circulation, fluid-rock interactions, and precipitation of a cement. Understanding the multi-scale processes of fracture network development in shales and the coupling with fluid circulation represents a key challenge for future research directions.

Treating tar sands formations with karsted zones

DOEpatents

Vinegar, Harold J.; Karanikas, John Michael

2010-03-09

Methods for treating a tar sands formation are described herein. The tar sands formation may have one or more karsted zones. Methods may include providing heat from one or more heaters to one or more karsted zones of the tar sands formation to mobilize fluids in the formation. At least some of the mobilized fluids may be produced from the formation.

Late-stage anhydrite-gypsum-siderite-dolomite-calcite assemblages record the transition from a deep to a shallow hydrothermal system in the Schwarzwald mining district, SW Germany

NASA Astrophysics Data System (ADS)

Burisch, Mathias; Walter, Benjamin F.; Gerdes, Axel; Lanz, Maximilian; Markl, Gregor

2018-02-01

The majority of hydrothermal vein systems of economic interest occur at relatively shallow crustal levels, although many of them formed at significantly greater depths. Their present position is a consequence of uplift and erosion. Although, many aspects of their formation are well constrained, the temporal chemical evolution of such systems during uplift and erosion is still poorly understood. These vein minerals comprise calcite, dolomite-ankerite, siderite-magnesite, anhydrite and gypsum forming the last gangue assemblages in Jurassic and Tertiary sulphide-fluorite-quartz-barite veins of the Schwarzwald mining district, SW Germany. Mineral textures of samples from nine localities reveal that in these sequences, mineral precipitation follows a recurring pattern: early calcite is followed by anhydrite or gypsum, siderite and/or dolomite. This succession may repeat up to three times. In-situ (LA-ICP-MS) U-Pb age dating of 15 carbonates from three subsequent generations of the late-stage vein assemblage yield robust ages between 20 and 0.6 Ma. Each mineral sequence forms in a distinctive period of about 2-5 Ma. These ages clearly relate these late-stage mineral phases to the youngest geological episode of the Schwarzwald, which is associated with the Cenozoic Rhine Graben rifting and basement uplift. Based on thermodynamic modelling, the formation of the observed mineral assemblages required an deeply sourced Mg-, Fe- and SO4-rich fluid (b), which was episodically mixed with a shallow crustal HCO3-rich fluid (a). As a consequence of fluid mixing, concentrations of Mg, Fe and SO4 temporarily increased and initiated the formation of the observed sulphate-carbonate mineral sequences. This discontinuous large-scale vertical fluid mixing was presumably directly related to episodes of active tectonics associated with the Cenozoic strike-slip regime of the Upper Rhine Graben. Analogously, episodic fluid mixing is a major key in the formation of older (Jurassic to early Tertiary) Pb-Zn-fluorite-quartz-barite assemblages in the same specific vein systems, albeit involving different fluid compositions. Late-stage hydrothermal (∼20-70 °C) vein assemblages reported in this study record the transition from deep (>2 km) to very shallow (0-1 km) crustal conditions. As a consequence of successive uplift, increasing proportions of shallower and cooler (∼50-70 °C) fluids could take part in such mixing processes. Associated changes in the fluid composition caused the vein mineralogy to change from sulphide-quartz-fluorite-barite to calcite-anhydrite/gypsum-siderite-dolomite, as the system passively ascended closer to the surface.

Long-lived interaction between hydrothermal and magmatic fluids in the Soultz-sous-Forêts granitic system (Rhine Graben, France)

NASA Astrophysics Data System (ADS)

Gardien, Véronique; Rabinowicz, Michel; Vigneresse, Jean-Louis; Dubois, Michel; Boulvais, Philippe; Martini, Rossana

2016-03-01

The 5 km deep drilling at Soultz-sous-Forêts samples a granitic intrusion under its sedimentary cover. Core samples at different depths allow study of the evolving conditions of fluid-rock interaction, from the syn-tectonic emplacement of Hercynian granites at depth until post-cooling history and alteration close to the surface. Hydrogen, carbon and oxygen isotope compositions of CO2 and H2O have been measured in fluid inclusions trapped in magmatic quartz within samples collected along the drill core. Early Fluid Inclusions Assemblage (FIA) contains aqueous carbonic fluids whereas the latest FIA are H2O-rich. In the early FIA, the amount of CO2 and the δ13C value both decrease with depth, revealing two distinct sources of carbon, one likely derived from sedimentary carbonates (δ13C = - 2‰ V-PDB) and another from the continental crust (δ13C = - 9‰ V-PDB). The carbon isotope composition of bulk granites indicates a third carbon source of organic derivation (δ13C = - 20‰ V-PDB). Using a δD - δ18O plot, we argue that the water trapped in quartz grains is mainly of meteoric origin somewhat mixed with magmatic water. The emplacement of the Soultz-sous-Forêts granite pluton occurred in a North 030-040° wrench zone. After consolidation of the granite mush at 600 °C, sinistral shear (γ 1) concentrated the final leucocratic melt in vertical planes oriented along (σ1, σ2). Crystallization of this residual leucocratic melt occurred while shearing was still active. At a temperature of 550 °C, crystallization ended with the formation of vertical quartz veins spaced about 5 mm, and exhibiting a width of several cm. The quartz veins form a connected network of a few kilometers in height, generated during hydrothermal contraction of the intrusion. Quartz crystallization led to the exsolution of 30% by volume of the aqueous fluid. As quartz grains were the latest solid phase still plastic, shearing localized inside the connected quartz network. Aqueous fluid was thus concentrated in these vertical channels. Eventually, when the channels intersected the top of the crack network, water boiling caused the formation of primary inclusions. At the same temperature, the saline magmatic waters, which were denser than the meteoric waters, initiated thermohaline convection with the buoyant "cold" hydrothermal water layer. This mechanism can explain the mixing of surface and deep-seated fluids in the same primary inclusions trapped during the crystallization of magmatic minerals. This study, which separately considers fluid-rock interactions at the level of successive mineral facies, brings new insights into how fluids may be different, their origin and composition, and depending on tectono-thermal conditions, bears implications for eventual ore forming processes.

Th-230 - U-238 series disequilibrium of the Olkaria rhyolites Gregory Rift Valley, Kenya: Petrogenesis

NASA Technical Reports Server (NTRS)

Black, S.; Macdonald, R.; Kelly, M.

1993-01-01

Positive correlations of (U-238/Th-230) versus Th show the rhyolites to be products of partial melting. Positive correlations of U and Cl and U and F show that the U enrichment in the rhyolites is associated with the halogen contents which may be related to the minor phenocryst phase fractionation. Instantaneous Th/U ratios exceed time integrated Th/U ratios providing further evidence of the hydrous nature of the Olkaria rhyolite source. Excess (U-238/Th-230) in the subduction related rocks has been associated to the preferential incorporation of uranium in slab derived fluids, but no evaluation of the size of this flux has been made. The majority of the Naivasha samples show a (U-238/Th-230) less than 1 and plot close to the subduction related samples indicating the Naivasha rhyolites may also have been influenced by fluids during their formation. In general samples with high (U-238/Th-230) ratios reflecting recent enrichment of uranium relative to thorium have high thorium contents, thereby the high (U-238/Th-230) ratios are restricted to the most incompatible element enriched magmas and, hence, are a good indication that the rhyolites were formed by partial melting. If a fluid phase had some influence on the formation of the rhyolites then the uranium and thorium may have some correlation with F and Cl contents which can be mirrored by the peralkalinity. Plots of uranium against F and Cl contents are shown. The positive correlation indicates that the uranium enrichments are associated with the halogen contents. There seems to be a greater correlation for U against Cl than F indicating that the U may be transported preferentially as Cl complexes.

Sample environment for in situ synchrotron XRD measurements for CO2 interaction with subsurface materials

NASA Astrophysics Data System (ADS)

Elbakhshwan, M.; Gill, S.; Weidner, R.; Ecker, L.

2017-12-01

Sequestration of CO2 in geological formations requires a deep understanding of its interaction with the cement-casing components in the depleted oil and gas wells. Portland cement is used to seal the wellbores; however it tends to interact with the CO2. Therefore it is critical to investigate the wellbore integrity over long term exposure to CO2. Studies showed that, CO2 leakage is due to the flow through the casing-cement microannulus, cement-cement fractures, or the cement-caprock interface. The objective of this work is to gain a better understanding of the dissolution process of the cement-casing in the CO2 flow channels alongside with the carbonation reactions at the interfaces using XRF, XANES and X-ray tomography techniques. In this study, a synthetic wellbore system, consisting of cement with an embedded rectangular length of steel casing that had grooves to accommodate fluid flow, was used to investigate the casing-cement microannulus through core-flood experiments. The objective of this work is to gain a better understanding of the dissolution process of the cement-casing in the CO2 flow channels alongside with the carbonation reactions at the interfaces using a sample environment designed and built for in situ X-ray diffraction in the National Synchrotron Light Source II (NSLS II). The formation of carbonate phases at cement -fluid and cement-steel/fluid interfaces will be monitored in real time. Samples may be exposed to super critical CO2 at pressures above 1100 psi and temperatures around 50°C. The reaction cell is built from hastealloy to provide corrosion resistance, while the experimental temperature and pressure are controlled with thermocouples and pressure vessel.

Systems and methods for separating particles and/or substances from a sample fluid

DOEpatents

Mariella, Jr., Raymond P.; Dougherty, George M.; Dzenitis, John M.; Miles, Robin R.; Clague, David S.

2016-11-01

Systems and methods for separating particles and/or toxins from a sample fluid. A method according to one embodiment comprises simultaneously passing a sample fluid and a buffer fluid through a chamber such that a fluidic interface is formed between the sample fluid and the buffer fluid as the fluids pass through the chamber, the sample fluid having particles of interest therein; applying a force to the fluids for urging the particles of interest to pass through the interface into the buffer fluid; and substantially separating the buffer fluid from the sample fluid.

Hydrothermal Signatures at Gale Crater, Mars, and Possible In-Situ Formation of Tridymite

NASA Astrophysics Data System (ADS)

Yen, A. S.; Morris, R. V.; Gellert, R.; Berger, J. A.; Sutter, B.; Downs, R. T.; Bristow, T.; Treiman, A. H.; Ming, D. W.; Achilles, C.; Blake, D. F.; Chipera, S.; Clark, B. C.; Craig, P.; Morrison, S. M.; Rampe, E. B.; Schmidt, M. E.; Schwenzer, S. P.; Thompson, L. M.; Vaniman, D.

2017-12-01

The occurrence of tridymite, a high temperature SiO2 polymorph definitively identified by the Curiosity rover in the Buckskin mudstone sample at Gale crater, Mars, has been attributed to detrital accumulation of rhyolitic material. This interpretation of a detrital origin is revisited in light of the observation that the tridymite-hosting sediments appear to have interacted with the same fluids that produced alteration halos in the overlying sandstone. The alteration halos in the Stimson sandstone are light-toned, elevated silica zones within 50 cm of a central fracture. They have likely experienced chemical leaching under acidic conditions resulting in depletion of metals (including Al), retention of Ti, formation of amorphous iron sulfates, 50% reduction of the pyroxene:plagioclase ratio, a factor of two increase in the Fe/Mn ratio, and passive enrichment of Si. This alteration is not constrained (nor precluded) to have occurred at elevated temperatures, but there are abundant indicators of hydrothermal activity within Gale crater. High concentrations of Ge, Zn, Ni, Pb, Cu, Se and Ga in a variety of samples analyzed by the Alpha Particle X-ray Spectrometer are indicative of mobility in hydrothermal solutions. Mineralogy of Gale crater samples determined by the CheMin X-ray diffraction instrument includes phases which may be associated with hydrothermal activity (smectites, anhydrite, hematite), but definitive detections of mineral assemblages that are necessarily hydrothermal in origin remain absent. The nearly identical patterns of enriched and depleted elements of the Stimson alteration halos (relative to parent rocks) and the tridymite-bearing unit (relative to typical mudstone samples) require the consideration of co-genetic origins. Cristobalite, a SiO2 polymorph stable above 1470°C found in the Buckskin sample, is known to form in hydrothermal solutions at temperatures well below its stability field (Henderson et al., 1971). Formation of well-crystalline tridymite at temperatures below its thermodynamic stability range (870-1470°C) has not been established, but cannot be excluded. Thus, the possibility that the fluids responsible for the passive enrichment of silica in the Stimson alteration halos also resulted in the in-situ formation of tridymite deserves further consideration.

A neurokinin 1 receptor antagonist decreases postoperative peritoneal adhesion formation and increases peritoneal fibrinolytic activity.

PubMed

Reed, Karen L; Fruin, A Brent; Gower, Adam C; Stucchi, Arthur F; Leeman, Susan E; Becker, James M

2004-06-15

Fibrous adhesions remain a major sequela of abdominal surgery. The proinflammatory peptide substance P (SP), known to participate in inflammatory events, may play a key role in adhesion formation. This hypothesis was tested by using an antagonist, CJ-12,255 (Pfizer), that blocks the binding of SP to the neurokinin 1 receptor (NK-1R). Adhesion formation was surgically induced in the peritoneum of rats receiving daily doses of the NK-1R antagonist (NK-1RA; 5.0 or 10.0 mg/kg per day) or saline. On postoperative day 7, both the low and high doses of NK-1RA significantly (P < 0.05) reduced adhesion formation by 45% and 53%, respectively, compared with controls. Subsequently, the effect of NK-1RA administration on peritoneal fibrinolytic activity was investigated to determine a potential mechanism for SP action in the peritoneum. Samples were collected from nonoperated controls and from animals 24 h postsurgery that were administered either NK-1RA or saline. Fibrinolytic activity in peritoneal fluid was assayed by zymography, and expression of tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1, both regulators of fibrinolytic activity, was assessed in peritoneal tissue and fluid by RT-PCR and bioassay, respectively. NK-1RA administration led to a marked (P < 0.05) increase in tPA mRNA levels in peritoneal tissue compared with nonoperated and saline-administered animals. Likewise, NK-1RA administration significantly (P < 0.05) increased tPA in the peritoneal fluid. These data suggest that activation of the NK-1R promotes peritoneal adhesion formation by limiting fibrinolytic activity in the postoperative peritoneum, thus enabling fibrinous adhesions to persist.

Determination of pharmacological levels of harmane, harmine and harmaline in mammalian brain tissue, cerebrospinal fluid and plasma by high-performance liquid chromatography with fluorimetric detection.

PubMed

Moncrieff, J

1989-11-24

Increased blood aldehyde levels, as occur in alcohol intoxication, could lead to the formation of beta-carbolines such as harmane by condensation with indoleamines. Endogenous beta-carbolines, therefore, should occur in specific brain areas where indoleamine concentrations are high, whilst exogenous beta-carbolines should exhibit an even distribution. The author presents direct and sensitive methods for assaying the beta-carbolines harmane, harmine and harmaline in brain tissue, cerebrospinal fluid and plasma at picogram sample concentrations using reversed-phase high-performance liquid chromatography with fluorimetric detection and minimal sample preparation. Using these assay methods, it was found that the distribution of beta-carbolines from a source exogenous to the brain results in a relatively even distribution within the brain tissue.

Downhole fluid injection systems, CO₂ sequestration methods, and hydrocarbon material recovery methods

DOEpatents

Schaef, Herbert T.; McGrail, B. Peter

2015-07-28

Downhole fluid injection systems are provided that can include a first well extending into a geological formation, and a fluid injector assembly located within the well. The fluid injector assembly can be configured to inject a liquid CO₂/H₂O-emulsion into the surrounding geological formation. CO₂ sequestration methods are provided that can include exposing a geological formation to a liquid CO₂/H₂O-emulsion to sequester at least a portion of the CO₂ from the emulsion within the formation. Hydrocarbon material recovery methods are provided that can include exposing a liquid CO₂/H₂O-emulsion to a geological formation having the hydrocarbon material therein. The methods can include recovering at least a portion of the hydrocarbon material from the formation.

New tracers identify hydraulic fracturing fluids and accidental releases from oil and gas operations.

PubMed

Warner, N R; Darrah, T H; Jackson, R B; Millot, R; Kloppmann, W; Vengosh, A

2014-11-04

Identifying the geochemical fingerprints of fluids that return to the surface after high volume hydraulic fracturing of unconventional oil and gas reservoirs has important applications for assessing hydrocarbon resource recovery, environmental impacts, and wastewater treatment and disposal. Here, we report for the first time, novel diagnostic elemental and isotopic signatures (B/Cl, Li/Cl, δ11B, and δ7Li) useful for characterizing hydraulic fracturing flowback fluids (HFFF) and distinguishing sources of HFFF in the environment. Data from 39 HFFFs and produced water samples show that B/Cl (>0.001), Li/Cl (>0.002), δ11B (25-31‰) and δ7Li (6-10‰) compositions of HFFF from the Marcellus and Fayetteville black shale formations were distinct in most cases from produced waters sampled from conventional oil and gas wells. We posit that boron isotope geochemistry can be used to quantify small fractions (∼0.1%) of HFFF in contaminated fresh water and likely be applied universally to trace HFFF in other basins. The novel environmental application of this diagnostic isotopic tool is validated by examining the composition of effluent discharge from an oil and gas brine treatment facility in Pennsylvania and an accidental spill site in West Virginia. We hypothesize that the boron and lithium are mobilized from exchangeable sites on clay minerals in the shale formations during the hydraulic fracturing process, resulting in the relative enrichment of boron and lithium in HFFF.

Studying microstructural dynamics of complex fluids with particle tracking microrheology

NASA Astrophysics Data System (ADS)

Breedveld, Victor

2004-11-01

Over the last decade, particle tracking microrheology has matured as a new tool for complex fluids research. The main advantages of microrheology over traditional macroscopic rheometry are: the required sample size is extremely small ( ˜ 1 microliter); local viscoelastic properties in a sample can be probed with high spatial resolution ( ˜1-10 micrometer); and the sample is not disturbed by moving rheometer parts. I will present two examples of recent work in my group that highlight how these characteristics can be exploited to acquire unique information about the microstructure of complex fluids. First, we have studied protein unfolding. Traditionally, protein unfolding is studied with spectroscopic techniques (circular dichroism, NMR, fluorescence). Although viscosity has been listed in textbooks as a suitable technique, few -if any- quantitative rheological studies of unfolding have been reported, mainly due to technical difficulties. With microrheology, we have been able to quantify the size of the folded and unfolded protein, as well as the Gibbs free energy of unfolding, for aqueous bovine serum albumine solutions upon addition of urea as a denaturant. The results are in excellent agreement with literature data. Secondly, we have developed new technology for studying the microstructural dynamics of solvent-responsive complex fluids. In macroscopic rheometry it is virtually impossible to change solvent composition and measure the rheological response of a sample. By integrating microfluidics and microrheology we have been able to overcome this barrier: due to the micrometer lengthscales in microfluidiv devices, diffusive timescales in a dialysis set-up become short enough to achieve rapid and reversible changes in sample composition, without affecting the concentration of macromolecular components. Our dialysis cell for microrheology is a unique tool for studying the dynamics of structural and rheological changes induced by solvent composition. I will present experimental results of calibration experiments that illustrate our quantitative understanding of the mass transport in the dialysis cell. Results will also be shown for the solvent-induced gel formation and break-up of alginate solutions. Alginate is a polysaccharide that only forms strong gels in the presence of multivalent cations; these gels are applied for drug delivery and in food products. The dialysis cell allows us to investigate the kinetics of the formation and break-up of these gels with high spatio-temporal resolution.

Ball assisted device for analytical surface sampling

DOEpatents

ElNaggar, Mariam S; Van Berkel, Gary J; Covey, Thomas R

2015-11-03

A system for sampling a surface includes a sampling probe having a housing and a socket, and a rolling sampling sphere within the socket. The housing has a sampling fluid supply conduit and a sampling fluid exhaust conduit. The sampling fluid supply conduit supplies sampling fluid to the sampling sphere. The sampling fluid exhaust conduit has an inlet opening for receiving sampling fluid carried from the surface by the sampling sphere. A surface sampling probe and a method for sampling a surface are also disclosed.

Dynamic strength, particle deformation, and fracture within fluids with impact-activated microstructures

NASA Astrophysics Data System (ADS)

Petel, Oren E.; Ouellet, Simon

2017-07-01

The evolution of material strength within several dense particle suspensions impacted by a projectile is investigated and shown to be strongly dependent on the particle material in suspension. For stronger particles, such as silicon carbide, the shear strength of the fluid is shown to increase with the ballistic impact strength. For weaker particles, such as silica, the shear strength of the suspension is found to be independent of impact strength in this dynamic range of tests. A soft-capture technique is employed to collect ejecta samples of a silica-based shear thickening fluid, following a ballistic impact and penetration event. Ejecta samples that were collected from impacts at three different velocities are observed and compared to the benchmark particles using a Scanning Electron Microscope. The images show evidence of fractured and deformed silica particles recovered among the nominally 1 μm diameter monodisperse spheres. There is also evidence of particle fragments that appear to be the result of interparticle grinding. The trends observed in the shear strength estimates are interpreted with regards to the particle damage seen in the ejecta recovery experiments to develop a concept of the impact response of these fluids. The results suggest that particle slip through deformation is likely the dominant factor in limiting the transient impact strength of these fluids. Particularly, particle strength is important in the formation and collapse of dynamically jammed particle contact networks in the penetration process.

Hydrothermal barite mineralization at Chenarvardeh deposit, Markazi Province, Iran: Evidences from REE geochemistry and fluid inclusions

NASA Astrophysics Data System (ADS)

Ehya, Farhad; Mazraei, Shaghayegh Moalaye

2017-10-01

Barite mineralization occurs at Chenarvardeh deposit as layers and lenses in Upper Eocene volcanic and pyroclastic rocks. The host rocks are intensely saussuritized in most places. Barite is accompanied by calcite, Mn-oxides, galena and malachite as subordinate minerals. The amount of Sr in barites is low and varies between 0.11 and 0.30 wt%. The concentration of Rb, Zr, Y, Ta and Hf is also low (<5 ppm) in barite samples. The amount of total REEs (∑REE) is low in barites, ranging from 7.51 to 30.50 ppm. Chondrite-normalized REE patterns reveal LREE enrichment with respect to HREE, and positive Ce anomalies. Fluid inclusions are common in barite samples, being dominantly from liquid-rich two phase (L + V) type. Salinity values in fluid inclusions range from 9.41 to 18.69 wt% NaCl equivalent with most frequent salinities falling in the range of 10-15 wt% NaCl equivalent. Homogenization temperatures (Th) range between 160 and 220 °C, being the 180-200 °C range as the most common Th interval. A combination of factors, including geologic setting, host rock, mineral assemblages, REE geochemistry and fluid inclusion data are consistent with a submarine volcanic hydrothermal model for barite formation at the Chenarvardeh deposit. Mineral-forming fluids originated from solutions related to submarine hydrothermal activities deposited barite on seafloor as they encountered sulfate-bearing seawater.

Supercritical fluid extraction of the non-polar organic compounds in meteorites

NASA Astrophysics Data System (ADS)

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

2001-01-01

The carbonaceous chondrite meteorites contain a variety of extraterrestrial organic molecules. These organic components provide a valuable insight into the formation and evolution of the solar system. Attempts at obtaining and interpreting this information source are hampered by the small sample sizes available for study and the interferences from terrestrial contamination. Supercritical fluid extraction represents an efficient and contamination-free means of isolating extraterrestrial molecules. Gas chromatography-mass spectrometry analyses of extracts from Orgueil and Cold Bokkeveld reveal a complex mixture of free non-polar organic molecules which include normal alkanes, isoprenoid alkanes, tetrahydronaphthalenes and aromatic hydrocarbons. These organic assemblages imply contributions from both terrestrial and extraterrestrial sources.

Chemical composition and geologic history of saline waters in Aux Vases and Cypress Formations, Illinois Basin

USGS Publications Warehouse

Demir, I.; Seyler, B.

1999-01-01

Seventy-six samples of formation waters were collected from oil wells producing from the Aux Vases or Cypress Formations in the Illinois Basin. Forty core samples of the reservoir rocks were also collected from the two formations. Analyses of the samples indicated that the total dissolved solids content (TDS) of the waters ranged from 43,300 to 151,400 mg/L, far exceeding the 35,400 mg/mL of TDS found in typical seawater. Cl-Br relations suggested that high salinities in the Aux Vases and Cypress formation waters resulted from the evaporation of original seawater and subsequent mixing of the evaporated seawater with concentrated halite solutions. Mixing with the halite solutions increased Na and Cl concentrations and diluted the concentration of other ions in the formation waters. The elemental concentrations were influenced further by diagenetic reactions with silicate and carbonate minerals. Diagenetic signatures revealed by fluid chemistry and rock mineralogy delineated the water-rock interactions that took place in the Aux Vases and Cypress sandstones. Dissolution of K-feldspar released K into the solution, leading to the formation of authigenic illite and mixed-layered illite/smectite. Some Mg was removed from the solution by the formation of authigenic chlorite and dolomite. Dolomitization, calcite recrystallization, and contribution from clay minerals raised Sr levels significantly in the formation waters. The trend of increasing TDS of the saline formation waters with depth can be explained with density stratification. But, it is difficult to explain the combination of the increasing TDS and increasing Ca/Na ratio with depth without invoking the controversial 'ion filtration' mechanism.

Osteoinduction on Acid and Heat Treated Porous Ti Metal Samples in Canine Muscle

PubMed Central

Kawai, Toshiyuki; Takemoto, Mitsuru; Fujibayashi, Shunsuke; Akiyama, Haruhiko; Tanaka, Masashi; Yamaguchi, Seiji; Pattanayak, Deepak K.; Doi, Kenji; Matsushita, Tomiharu; Nakamura, Takashi; Kokubo, Tadashi; Matsuda, Shuichi

2014-01-01

Samples of porous Ti metal were subjected to different acid and heat treatments. Ectopic bone formation on specimens embedded in dog muscle was compared with the surface characteristics of the specimen. Treatment of the specimens by H2SO4/HCl and heating at 600°C produced micrometer-scale roughness with surface layers composed of rutile phase of titanium dioxide. The acid- and heat-treated specimens induced ectopic bone formation within 6 months of implantation. A specimen treated using NaOH followed by HCl acid and then heat treatment produced nanometer-scale surface roughness with a surface layer composed of both rutile and anatase phases of titanium dioxide. These specimens also induced bone formation after 6 months of implantation. Both these specimens featured positive surface charge and good apatite-forming abilities in a simulated body fluid. The amount of the bone induced in the porous structure increased with apatite-forming ability and higher positive surface charge. Untreated porous Ti metal samples showed no bone formation even after 12 months. Specimens that were only heat treated featured a smooth surface composed of rutile. A mixed acid treatment produced specimens with micrometer-scale rough surfaces composed of titanium hydride. Both of them also showed no bone formation after 12 months. The specimens that showed no bone formation also featured almost zero surface charge and no apatite-forming ability. These results indicate that osteoinduction of these porous Ti metal samples is directly related to positive surface charge that facilitates formation of apatite on the metal surfaces in vitro. PMID:24520375

The composition of fluid inclusions in ore and gangue minerals from the Silesian-Cracow Mississippi Valley-type Zn-Pb deposits Poland: Genetic and environmental implications

USGS Publications Warehouse

Viets, J.G.; Hofstra, A.H.; Emsbo, P.; Kozlowski, A.

1996-01-01

The composition of fluids extracted from ore and gangue sulfide minerals that span most of the paragenesis of the Silesian-Cracow district was determined using a newly developed ion chromatographic (IC) technique. Ionic species determined were Na+, NH+4, Ca2+, Mg2+, K+, Rb+, Sr2+, Ba2+, Cl-, Br-, F-, I-, PO3-4, CO2-3, HS-, S2O2-3, SO2-4, NO-3, and acetate. Mineral samples included six from the Pomorzany mine and one from the Trzebionka mine which are hosted in the Triassic Muschelkalk Formation, and two samples of drill core from mineralized Upper Devonian strata. Nine paragenetically identifiable sulfide minerals occur throughout the Silesian-Cracow district. These include from earliest to latest: early iron sulfides, granular sphalerite, early galena, light-banded sphalerite, galena, dark-banded sphalerite, iron sulfides, late dark-banded sphalerite with late galena, and late iron sulfides. Seven of the minerals were sampled for fluid inclusion analysis in this study. Only the early iron sulfides and the last galena stage were not sampled. Although the number of analyses are limited to nine samples and two replicates and there is uncertainty about the characteristics of the fluid inclusions analyzed, the data show clear temporal trends in the composition of the fluids that deposited these minerals. Fluid inclusions in minerals deposited later in the paragenesis have significantly more K+, Br-, NH+4, and acetate but less Sr2+ than those deposited earlier in the paragenesis. The later minerals are also characterized by isotopically lighter sulfur and significantly more Tl and As in the solid minerals. The change in ore-fluid chemistry is interpreted to reflect a major change in the hydrologic regime of the district. Apparently, the migrational paths of ore fluids from the Upper Silesian basin changed during ore deposition and the fluids which deposited early minerals reacted with aquifers with very different geochemical characteristics than those that deposited late minerals. The early fluids may have reacted primarily with Devonian and Lower Carboniferous carbonate aquifers deeper in the basin, whereas the later fluids appear to have had extensive contact with organic-rich rocks, probably the shallower Middle and Upper Carboniferous flysch associated with coal measures. High concentrations of toxic Tl and As occur in the readily oxidized marcasite and pyrite minerals deposited by the later fluids. In general, the geochemistry of both the early and late fluids may be explained by an evaporite related origin or by water-rock modification of a saline basinal brine. When compared to the composition of fluid inclusions in Mississippi Valley-type (MVT) ore minerals from the Ozark region of the United States, fluid inclusions in minerals from Silesian-Cracow are fundamentally different, containing more Ca2+, Mg2+, NH+4, Br-, Sr2+ and acetate in all mineral stages with significantly more K+ in later stage minerals. The differences in ore fluid chemistry between the two regions are consistent with the lithologic differences of the respective basins thought to be the source of the mineralizing brines.

Optimizing drilling performance using a selected drilling fluid

DOEpatents

Judzis, Arnis [Salt Lake City, UT; Black, Alan D [Coral Springs, FL; Green, Sidney J [Salt Lake City, UT; Robertson, Homer A [West Jordan, UT; Bland, Ronald G [Houston, TX; Curry, David Alexander [The Woodlands, TX; Ledgerwood, III, Leroy W.

2011-04-19

To improve drilling performance, a drilling fluid is selected based on one or more criteria and to have at least one target characteristic. Drilling equipment is used to drill a wellbore, and the selected drilling fluid is provided into the wellbore during drilling with the drilling equipment. The at least one target characteristic of the drilling fluid includes an ability of the drilling fluid to penetrate into formation cuttings during drilling to weaken the formation cuttings.

Timing of Hydrocarbon Fluid Emplacement in Sandstone Reservoirs in Neogene in Huizhou Sag, Southern China Sea, by Authigenic Illite 40Ar- 39Ar Laser Stepwise Heating

NASA Astrophysics Data System (ADS)

Hesheng, Shi; Junzhang, Zhu; Huaning, Qiu; yu, Shu; Jianyao, Wu; Zulie, Long

Timing of oil or gas emplacements is a new subject in isotopic geochronology and petroleum geology. Hamilton et al. expounded the principle of the illite K-Ar age: Illite is often the last or one of the latest mineral cements to form prior to hydrocarbon accumulation. Since the displacement of formation water by hydrocarbons will cause silicate diagenesis to cease, K-Ar ages for illite will constrain the timing of this event, and also constrain the maximum age of formation of the trap structure. In this study, the possibility of authigenic illites 40Ar- 39Ar dating has been investigated. The illite samples were separated from the Tertiary sandstones in three rich oil reservoir belts within the Huizhou sag by cleaning, fracturing by cycled cooling-heating, soxhlet-extraction with solvents of benzene and methanol and separating with centrifugal machine. If oil is present in the separated samples, ionized organic fragments with m/e ratios of 36 to 40 covering the argon isotopes will be yielded by the ion source of a mass spectrometer, resulting in wrong argon isotopic analyses and wrong 40Ar- 39Ar ages. The preliminary experiments of illite by heating did show the presence of ionized organic fragments with m/e ratios of 36 to 44. In order to clean up the organic gases completely and obtain reliable analysis results, a special purification apparatus has been established by Qiu et al. and proved valid by the sequent illite analyses. All the illite samples by 40Ar- 39Ar IR-laser stepwise heating yield stair-up age spectra in lower laser steps and plateaux in higher laser steps. The youngest apparent ages corresponding to the beginning steps are reasonable to be interpreted for the hydrocarbon accumulation ages. The weighted mean ages of the illites from the Zhuhai and Zhujiang Formations are (12.1 ± 1.1) Ma and (9.9 ± 1.2) Ma, respectively. Therefore, the critical emplacement of petroleum accumulation in Zhujiang Formation in Huizhou sag took place in ca 10 Ma. Late fault activity strengthened the entrance of hydrocarbon fluids into the oil systems based on the data of the studies of the fault evolvement history, petroleum system combinations, and homogeneous temperatures of fluid inclusions.

Computerized X-ray Microtomography Observations and Fluid Flow Measurements of the Effect of Effective Stress on Fractured Reservoir Seal Shale

NASA Astrophysics Data System (ADS)

Welch, N.; Crawshaw, J.; Boek, E.

2014-12-01

The successful storage of carbon dioxide in geologic formations requires an in-depth understanding of all reservoir characteristics and morphologies. An intact and substantial seal formation above a storage reservoir is required for a significant portion of the initial sealing mechanisms believed to occur during carbon dioxide storage operations. Shales are a common seal formation rock types found above numerous hydrocarbon reservoirs, as well as potential saline aquifer storage locations. Shales commonly have very low permeability, however they also have the tendency to be quite fissile, and the formation of fractures within these seals can have a significant detrimental effect on the sealing potential of a reservoir and amount to large areas of high permeability and low capillary pressures compared to the surrounding intact rock. Fractured shales also have an increased current interest due to the increasing development of shale gas reservoirs using hydraulic fracturing techniques. This work shows the observed changes that occur within fractured pieces of reservoir seal shale samples, along with quarry analogues, using an in-situ micro-CT fluid flow imaging apparatus with a Hassler type core holder. Changes within the preferential flow path under different stress regimes as well as physical changes to the fracture geometry are reported. Lattice Boltzmann flow simulations were then performed on the extracted flow paths and compared to experiment permeability measurements. The preferential flow path of carbon dioxide through the fracture network is also observed and compared to the results two-phase Lattice Boltzmann fluid flow simulations.

Pressure/temperature fluid cell apparatus for the neutron powder diffractometer instrument: probing atomic structure in situ.

PubMed

Wang, Hsiu-Wen; Fanelli, Victor R; Reiche, Helmut M; Larson, Eric; Taylor, Mark A; Xu, Hongwu; Zhu, Jinlong; Siewenie, Joan; Page, Katharine

2014-12-01

This contribution describes a new local structure compatible gas/liquid cell apparatus for probing disordered materials at high pressures and variable temperatures in the Neutron Powder Diffraction instrument at the Lujan Neutron Scattering Center, Los Alamos National Laboratory. The new sample environment offers choices for sample canister thickness and canister material type. Finite element modeling is utilized to establish maximum allowable working pressures of 414 MPa at 15 K and 121 MPa at 600 K. High quality atomic pair distribution function data extraction and modeling have been demonstrated for a calibration standard (Si powder) and for supercritical and subcritical CO2 measurements. The new sample environment was designed to specifically target experimental studies of the local atomic structures involved in geologic CO2 sequestration, but will be equally applicable to a wide variety of energy applications, including sorption of fluids on nano/meso-porous solids, clathrate hydrate formation, catalysis, carbon capture, and H2 and natural gas uptake/storage.

Experimental study of the mechanism and sequence of calcite-dolomite replacement

NASA Astrophysics Data System (ADS)

Moraila-Martinez, Teresita; Putnis, Christine V.; Putnis, Andrew

2015-04-01

For many years the formation, mechanism and environmental settings of dolomite formation have been under discussion, mainly because dolomite is commonly found in ancient rocks, whereas it is rarely present in modern sediments. The most favoured hypothesis is the 'dolomitization' of limestone by Mg-bearing aqueous solutions [1,2]. The existence of sharp limestone-dolomite contacts in natural rocks suggests that dolomitization involves a coupled dissolution-precipitation process. For a better understanding of the replacement mechanism of calcite by dolomite we performed hydrothermal experiments using Carrara marble cubes of 1.5 mm size, that reacted with 1M (Ca,Mg)Cl2 solutions with a Mg:Ca ratio of 3, at 200°C for different duration times (10, 20, 40, 50 and 58 days). After reaction, the product phases were characterized using Raman spectroscopy, electron microprobe analysis, and scanning electron microscopy. After reaction, the external morphology of the samples was preserved. Back-scattered images revealed two replacement end products: dolomite and magnesite. Grain boundaries of the samples were maintained. Shorter time duration experiments resulted in the replacement reaction occurring mainly along grain boundaries, whereas in longer duration time experiments more replacement was located in the core of the sample. In this type of reaction, grain boundaries are very important for the replacement to occur, acting as fluid pathways, allowing the infiltration of the solution further from the rock surface, enhancing fluid permeability within the sample and allowing further replacement reactions to occur. 1. Kaczmarek S.E., Sibley D.F. On the evolution of dolomite stoichiometry and cation order during high temperature synthesis experiments: An alternative model for geochemical evolution of natural dolomites. Sedimentary Geology. 240, 30-40 (2011). 2. Etschmann B., Brugger J., Pearce M.A., Ta C., Brautigan D., Jung M., Pring A. Grain boundaries as microreactors during reactive fluid flow: experimental dolomitization of a calcite marble. Contributions to Mineralogy and Petrology. 168:1045 (2014).

Initial characterization of mudstone nanoporosity with small angle neutron scattering using caprocks from carbon sequestration sites.

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCray, John; Navarre-Sitchler, Alexis; Mouzakis, Katherine

Geological carbon sequestration relies on the principle that CO{sub 2} injected deep into the subsurface is unable to leak to the atmosphere. Structural trapping by a relatively impermeable caprock (often mudstone such as a shale) is the main trapping mechanism that is currently relied on for the first hundreds of years. Many of the pores of the caprock are of micrometer to nanometer scale. However, the distribution, geometry and volume of porosity at these scales are poorly characterized. Differences in pore shape and size can cause variation in capillary properties and fluid transport resulting in fluid pathways with different capillarymore » entry pressures in the same sample. Prediction of pore network properties for distinct geologic environments would result in significant advancement in our ability to model subsurface fluid flow. Specifically, prediction of fluid flow through caprocks of geologic CO{sub 2} sequestration reservoirs is a critical step in evaluating the risk of leakage to overlying aquifers. The micro- and nanoporosity was analyzed in four mudstones using small angle neutron scattering (SANS). These mudstones are caprocks of formations that are currently under study or being used for carbon sequestration projects and include the Marine Tuscaloosa Group, the Lower Tuscaloosa Group, the upper and lower shale members of the Kirtland Formation, and the Pennsylvanian Gothic shale. Total organic carbon varies from <0.3% to 4% by weight. Expandable clay contents range from 10% to {approx}40% in the Gothic shale and Kirtland Formation, respectively. Neutrons effectively scatter from interfaces between materials with differing scattering length density (i.e. minerals and pores). The intensity of scattered neutrons, I(Q), where Q is the scattering vector, gives information about the volume of pores and their arrangement in the sample. The slope of the scattering data when plotted as log I(Q) vs. log Q provides information about the fractality or geometry of the pore network. Results from this study, combined with high-resolution TEM imaging, provide insight into the differences in volume and geometry of porosity between these various mudstones.« less

Treating tar sands formations with dolomite

DOEpatents

Vinegar, Harold J.; Karanikas, John Michael

2010-06-08

Methods for treating a tar sands formation are described herein. The tar sands formation may include dolomite and hydrocarbons. Methods may include providing heat at less than the decomposition temperature of dolomite from one or more heaters to at least a portion of the formation. At least some of the hydrocarbon fluids are mobilized in the formation. At least some of the hydrocarbon fluids may be produced from the formation.

Iron isotope fractionation among magnetite, pyrrhotite, chalcopyrite, rhyolite melt and aqueous fluid at magmatic-hydrothermal conditions

NASA Astrophysics Data System (ADS)

Bilenker, L. D.; Simon, A.; Lundstrom, C.; Gajos, N.

2012-12-01

Fractionation of non-traditional stable isotopes (NTSI) such as Fe in magmatic systems is a relatively understudied subject. The fractionation of Fe stable isotopes has been quantified in some natural igneous samples, but there is a paucity of experimental data that could provide further insight into the causative processes of the observed fractionation. Substantial experimental work has been performed at higher temperatures pertaining to the formation of chondrites and the Earth's core, but only a handful of studies have addressed crustal rocks. To fill this knowledge gap, we performed isothermal, isobaric experiments containing mineral (e.g., magnetite, Fe-sulfides) and fluid, or mineral, rhyolite melt, and fluid assemblages to quantify equilibrium fractionation factors (α). These data, to our knowledge, are the first data that quantify the effect of a fluid phase on iron isotope fractionation at conditions appropriate for evolving magmatic systems. Charges were run inside gold capsules held in a René-41 cold seal vessel, and heated to 400, 600, or 800°C at 150 MPa for mineral-fluid, and 800°C and 100 MPa for mineral-melt-fluid runs. Use of the René vessel fixed the fO2 at the NNO buffer, an oxidation state consistent with arc magmas. The isotopic compositions of the starting and quenched phases were obtained by using a Multi-Collector Plasma Mass Spectrometer (MC-ICP-MS). Equilibrium was assessed by performing time-series runs and the three-isotope method, used only once before in a similar Fe isotope study. Correlation between Fe isotope mass and oxidation state is also being explored. Magnetite-fluid results indicate enrichment of heavy Fe isotopes in the mineral relative to the fluid, consistent with measurements of felsic igneous rocks. Magnetite-melt-fluid relationships are also consistent with measurements of natural samples. In the latter assemblage, over the course of the run, the rhyolite melt becomes heavy relative to the fluid while magnetite takes on a heavier Fe isotope signature than the starting value. These data corroborate the hypothesis that fluid exsolution caused the isotopic patterns observed in highly-differentiated igneous rocks. Further, owing to the ubiquitous importance of melt degassing as a critical process for the formation of magmatic-hydrothermal ore deposits, these data may be potentially serve as an exploration tool. This work contributes to our overall understanding of igneous processes by elucidating the Fe isotope fingerprints observed in the field as well as develop the laboratory techniques needed to study NTSI fractionation in magmatic systems and build a reliable dataset for interpretation of natural systems.

Creating fluid injectivity in tar sands formations

DOEpatents

Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

2012-06-05

Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons including mobilized hydrocarbons are produced from the portion.

Creating fluid injectivity in tar sands formations

DOEpatents

Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

2010-06-08

Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Djabbarah, N.F.

A miscible displacement process for recovering oil from a subterranean, oil-containing formation penetrated by at least one injection well and at least one spaced-apart production well and having fluid communication between the injection and the production wells is described comprising: (a) injecting a slug of til oil into the formation through the injection well; (b) injecting a slug of a displacing fluid into the formation through the injection well, the displacing fluid being selected from the group consisting of carbon monoxide, carbon dioxide, methane, nitrogen, air, flue gas, combustion gas and mixtures thereof, the injection of the tall oil loweringmore » the minimum miscibility pressure of the displacing fluid in the formation oil; and (c) recovering the oil through the production well.« less

Methane Hydrate Fformation in a Coarse-Grained, Brine-Saturated Sample Through the Induction of a Propagating Gas Front

NASA Astrophysics Data System (ADS)

Meyer, D.

2016-12-01

We generate methane hydrate in a coarse-grained, brine-saturated, vertically-oriented sample through gas injection. From 0 - 80 hours, we estimate a hydrate saturation of 0.56 behind the formation front, using mass balance, indicating that hydrate formation is limited by locally-elevated salinity creating three-phase equilibrium conditions. After 80 hours, the hydrate phase saturation drops to 0.50 and the magnitude of the pressure drop-rebound cycles increases, suggesting temporary reductions in permeability and the development of heterogeneous distributions of free gas in the sample. The sample consists of an industrial, fine sand mixed with a 0.5 wt% fraction of natural, smectitic clay from the Eugene Island region in the Gulf of Mexico (5.08cm diameter, 11.79cm length). The sample is initially saturated with a 7 wt% sodium chloride brine, pressurized to 12.24 MPa, and cooled to 1 degree Celsius, to bring the sample into the hydrate stability zone. Syringe pumps filled with methane gas and brine are connected to the top and bottom of the sample, respectively, to control fluid flow. We withdraw from the base of the sample at a rate of 0.0005 mL/min and inject methane to maintain a constant pressure, initiating hydrate formation. We analyze this experiment, as well as a gas flood experiment executed under the same conditions, using computed-tomography scans and an analytical solution to investigate the formation behavior and thermodynamic state of hydrate in gas-rich, coarse-grained reservoirs.

Simulation of the formation of nonequilibrium structures in magnetorheological fluids subject to an external magnetic field

NASA Astrophysics Data System (ADS)

Mohebi, M.; Jamasbi, N.; Liu, Jing

1996-11-01

We developed a computer model to understand the nonequilibrium structures induced in a magnetorheological (MR) fluid by rapidly applying an external magnetic field. MR fluids consist of particles suspended in a liquid where particles interact through dipole moments induced by the external magnetic field. We have simulated these induced structures in both directions, parallel and perpendicular to the field, in the limit of fastest response, by neglecting thermal motion and applying the field instantaneously. Our results show that the process of structure formation starts with particles forming chains aligned with the external field. The chains then coalesce to form columns and wall-like structures (``worms'' as viewed from the top). The complexity of this pattern is found to depend on the concentration of particles and the confinement of the cell in the direction of the external field. These results are consistent with experimental observations [G.A. Flores et al., in Proceedings of the Fifth International Conference on ER Fluids, MR Suspensions, and Associate Technology, University of Sheffield, Sheffield, 1995, edited by W. Bullough (World Scientific, Singapore, 1996), p. 140]. We have also used this model to study the interaction of two chains. The results of this study help in the understanding of the connection between the thickness of the sample and the increased complexity of the observed lateral pattern.

Fluid Characteristics and Evolution of Chelungpu fault of Taiwan

NASA Astrophysics Data System (ADS)

Song, S. R.

2017-12-01

We analyzed geochemical characteristics, such as hydrogen and oxygen isotopes, and ionic concentrations, of fluid samples retrieved from various depth along boreholes of the Hole A and Hole B of Taiwan Chelungpu fault Drilling Project(TCDP) to trace the fluid sources. The results show that the source of fluid in the Hole B is mainly the tap water, while there are two probable sources in the Hole A owing to the abrupt shift of ionic concentrations at the depth of 200-300 m. The shallower fluid might be from the leakage above the depth of 300 m and is characteristic of lower ionic concentrations and the isotopic ratios are close to those of adjacent river water. However, the deeper fluid should be the thermal water from Kueichulin formation because of high ionic concentrations, especially HCO3-, and higher oxygen isotope, which suggests higher temperature and more isotope exchange. Two sources of fluid of the Hole A are representative of the fluid systems in the hanging wall and foot wall respectively. The characteristics of fluids in the Hole A imply that the fault zone serves as a barrier in the inter-seismic period, resulting in distinctly different fluid between the Hanging wall and the foot wall. The frequent occurrence and the distribution of calcite veins provide the evidence of the upwelling of HCO3-rich fluid of Kueichulin formation and indicate that the fault served as fluid conduit during faulting and allowed the fluid flow across the fault zone to precipitate calcite veins in fractures of the hanging wall. Thus, we can deduce the mechanism of local groundwater flow during different stages of fault development by evidences such as calcite veins distribution, regional groundwater geology, and fluids characteristics in boreholes of the Hole-A and Hole B. During inter-seismic period, groundwater flows below and above the fault zone are separated by the impermeable fault gouge layer. In co-seismic time, faulting breaks the gouge layer, providing openings that let the over-pressured thermal water which contained high concentration of bicarbonate ion to surge up. After co-seismic period, the gouge layer is sealed again, residual thermal water which contained high concentration of bicarbonate ion in the hanging wall gradually precipitated calcite in fractures and the closer precipitation took place, the more calcite veins.

Organic tissues, graphite, and hydrocarbons in host rocks of the Rum Jungle Uranium Field, northern Australia

USGS Publications Warehouse

Foster, C.B.; Robbins, E.I.; Bone, Y.

1990-01-01

The Rum Jungle Uranium field consists of at least six early Proterozoic deposits that have been mined either for uranium and/or the associated base and precious metals. Organic matter in the host rocks of the Whites Formation and Coomalie Dolomite is now predominantly graphite, consistent with the metamorphic history of these rocks. For nine samples, the mean total organic carbon content is high (3.9 wt%) and ranged from 0.33 to 10.44 wt%. Palynological extracts from the host rocks include black, filamentous, stellate (Eoastrion-like), and spherical morphotypes, which are typical of early Proterozoic microbiota. The colour, abundance, and shapes of these morphotypes reflect the thermal history, organic richness, and probable lacustrine biofacies of the host rocks. Routine analysis of rock thin sections and of palynological residues shows that mineral grains in some of the host rocks are coated with graphitized organic matter. The grain coating is presumed to result from ultimate thermal degradation of a petroleum phase that existed prior to metamorphism. Hydrocarbons are, however, still present in fluid inclusions within carbonates of the Coomalie Dolomite and lower Whites Formation. The fluid inclusions fluoresce dull orange in blue-light excitation and their hydrocarbon content is confirmed by gas chromatography of whole-rock extracts. Preliminary analysis of the oil suggests that it is migrated, and because it has escaped graphitization through metamorphism it is probably not of early Proterozoic age. The presence of live oil is consistent with fluid inclusion data that suggest subsequent, low-temperature brine migration through the rocks. The present observations support earlier suggestions that organic matter in the host formations trapped uranium to form protore. Subsequent fluid migrations probably brought additional uranium and other metals to these formations, and the organic matter provided a reducing environment for entrapment. ?? 1990.

Characterization of a Monoclonal Antibody Directed against Mytilus spp Larvae Reveals an Antigen Involved in Shell Biomineralization

PubMed Central

Calvo-Iglesias, Juan; Pérez-Estévez, Daniel; Lorenzo-Abalde, Silvia; Sánchez-Correa, Beatriz; Quiroga, María Isabel; Fuentes, José M.; González-Fernández, África

2016-01-01

The M22.8 monoclonal antibody (mAb) developed against an antigen expressed at the mussel larval and postlarval stages of Mytilus galloprovincialis was studied on adult samples. Antigenic characterization by Western blot showed that the antigen MSP22.8 has a restricted distribution that includes mantle edge tissue, extrapallial fluid, extrapallial fluid hemocytes, and the shell organic matrix of adult samples. Other tissues such as central mantle, gonadal tissue, digestive gland, labial palps, foot, and byssal retractor muscle did not express the antigen. Immunohistochemistry assays identified MSP22.8 in cells located in the outer fold epithelium of the mantle edge up to the pallial line. Flow cytometry analysis showed that hemocytes from the extrapallial fluid also contain the antigen intracellularly. Furthermore, hemocytes from hemolymph have the ability to internalize the antigen when exposed to a cell-free extrapallial fluid solution. Our findings indicate that hemocytes could play an important role in the biomineralization process and, as a consequence, they have been included in a model of shell formation. This is the first report concerning a protein secreted by the mantle edge into the extrapallial space and how it becomes part of the shell matrix framework in M. galloprovincialis mussels. PMID:27008638

Ridge-flank crustal microbiology investigated with long-term borehole observatories

NASA Astrophysics Data System (ADS)

Orcutt, B. N.; Bach, W.; Becker, K.; Edwards, K. J.; Fisher, A. T.; Haddad, A.; Hulme, S.; Teske, A.; Toner, B.; Wheat, C. G.

2011-12-01

The ridge flank environment represents an important habitat for microbial life on Earth, considering its size and chemical disequilibria between circulating fluids and rocks. However, the potential for this habitat to harbor life, and the characteristics that such life might have, are poorly known at present. Furthermore, the interactions of microbial communities across deep sediment-basement interfaces are not well-characterized. Subseafloor borehole observatories provide a novel platform for sampling and monitoring the microbiology of the crustal ridge flank environment. We present current results from a series of subsurface microbial colonization experiments using borehole observatories on the eastern flank of the Juan de Fuca Ridge, as well as analysis of samples collected on a transect away from a seawater-recharging seamount on this ridge flank. These results are compared to the microbiology of observatories installed in the Costa Rica Rift flank with similar fluid composition and temperatures (i.e. anoxic and warm). We will also discuss on-going experiments on the western-flank of the Mid-Atlantic Ridge, where formation fluids in basement are oxic and cool. Results from these experiments represent some of the extremes in crustal fluid conditions, paving the way for additional studies that are needed to address the importance of this biome as a carbon reservoir and a mechanism for crustal alteration.

The Rapid Formation of Localized Compaction Bands Under Hydrostatic Load Leading to Pore-pressure Transients in Compacting Rocks

NASA Astrophysics Data System (ADS)

Faulkner, D.; Leclere, H.; Bedford, J. D.; Behnsen, J.; Wheeler, J.

2017-12-01

Compaction of porous rocks can occur uniformly or within localized deformation bands. The formation of compaction bands and their effects on deformation behaviour are poorly understood. Porosity may be primary and compaction can occur with burial, or it can be produced by metamorphic reactions with a solid volume reduction, that can then undergo collapse. We report results from hydrostatic compaction experiments on porous bassanite (CaSO4.0.5H2O) aggregates. Gypsum (CaSO4.2H2O) is first dehydrated under low effective pressure, 4 MPa, to produce a bassanite aggregate with a porosity of 27%. Compaction is induced by increasing confining pressure at rates from 0.001 MPa/s to 0.02 MPa/s while the sample is maintained at a temperature of 115°C. At slow compaction rates, porosity collapse proceeds smoothly. At higher compaction rates, sudden increases in the pore-fluid pressure occur with a magnitude of 5 MPa. Microstructural investigations using X-ray microtomography and SEM observations show that randomly oriented localized compaction features occur in all samples, where the bulk porosity of 18% outside the band is reduced to 5% inside the band. Previous work on deformation bands has suggested that localized compactive features only form under an elevated differential stress and not under a hydrostatic stress state. The magnitude of the pore-pressure pulses can be explained by the formation of compaction bands. The results indicate that the compaction bands can form by rapid (unstable) propagation across the sample above a critical strain rate, or quasi-statically at low compaction rates without pore-fluid pressure bursts. The absence of pore-fluid pressure bursts at slow compaction rates can be explained by viscous deformation of the bassanite aggregate around the tip of a propagating compaction band, relaxing stress, and promoting stable propagation. Conversely, at higher compaction rates, viscous deformation cannot relax the stress sufficiently and unstable, brittle propagation occurs. In nature, this type of compaction behaviour might result in a mechanism to produce pulses of pore pressure within porous rocks which might have a significant effect on the deformation behaviour at depth.

Melatonin in human preovulatory follicular fluid

NASA Technical Reports Server (NTRS)

Brzezinski, Amnon; Seibel, Machelle M.; Lynch, Harry J.; Deng, Mei-Hua; Wurtman, Richard J.

1987-01-01

Melatonin, the major hormone of the pineal gland, has antigonadotrophic activity in many mammals and may also be involved in human reproduction. Melatonin suppresses steroidogenesis by ovarian granulosa and luteal cells in vitro. To determine if melatonin is present in the human ovary, preovulatory follicular fluids (n = 32) from 15 women were assayed for melatonin by RIA after solvent extraction. The fluids were obtained by laparoscopy or sonographically controlled follicular puncture from infertile women undergoing in vitro fertilization and embryo transfer. All patients had received clomiphene citrate, human menopausal gonadotropin, and hCG to stimulate follicle formation. Blood samples were obtained by venipuncture 30 min or less after follicular aspiration. All of the follicular fluids contained melatonin, in concentrations (35.6 plus or minus 4.8 (plus or minus SEM) pg/mL) substantially higher than those in the corresponding serum (10.0 plus or minus 1.4 pg/mL). A positive correlation was found between follicular fluid and serum melatonin levels in each woman (r = 0.770; P less than 0.001). These observations indicate that preovulatory follicles contain substantial amounts of melatonin that may affect ovarian steroidogenesis.

Multispecies Biofilm Development on Space Station Heat Exhanger Core Material

NASA Technical Reports Server (NTRS)

Pyle, B. H.; Roth, S. R.; Vega, L. M.; Pickering, K. D.; Alvarez, Pedro J. J.; Roman, M. C.

2007-01-01

Investigations of microbial contamination of the cooling system aboard the International Space Station (ISS) suggested that there may be a relationship between heat exchanger (HX) materials and the degree of microbial colonization and biofilm formation. Experiments were undertaken to test the hypothesis that biofilm formation is influenced by the type and previous exposure of HX surfaces. Acidovorax delafieldii, Comamonas acidovorans, Hydrogenophaga pseudoflava, Pseudomonas stutzeri, Sphingomonas paucimobilis, and Stenotrophomonas maltophilia, originally isolated from ISS cooling system fluid, were cultured on R2A agar and suspended separately in fresh filter-sterilized ISS cooling fluid, pH 8.3. Initial numbers in each suspension ranged from 10(exp 6)-10(exp 7) CFU/ml, and a mixture contained greater than 10(exp 7) CFU/ml. Coupons of ISS HX material, previously used on orbit (HXOO) or unused (HXUU), polycarbonate (PC) and 316L polished stainless steel (SS) were autoclaved, covered with multispecies suspension in sterile tubes and incubated in the dark at ambient (22-25 C). Original HX material contained greater than 90% Ni, 4.5% Si, and 3.2% B, with a borate buffer. For approximately 10 weeks, samples of fluid were plated on R2A agar, and surface colonization assessed by SYBR green or BacLight staining and microscopy. Suspension counts for the PC and SC samples remained steady at around 10(exp 7) CFU/ml. HXUU counts declined about 1 log in 21 d then remained steady, and HXOO counts declined 2 logs in 28 d, fluctuated and stabilized about 10(exp 3) CFU/ml from 47-54 d. Predominantly yellow S. paucimobilis predominated on plates from HXOO samples up to 26 d, then white or translucent colonies of other species appeared. All colony types were seen on plates from other samples throughout the trial. Epifluorescence microscopy indicated microbial growth on all surfaces by 21 d, followed by variable colonization. After 54 d, all but the HXOO samples had well-distributed live and dead cells; the HXOO samples had few cells and most were live by BacLight. The results suggest that HX materials themselves are inhibiting microbial growth on the surfaces. The HX exposed on orbit to cooling system fluid inhibited growth of some species originally isolated from the system, whereas the unused HX material had a moderate effect compared to no inhibition with PC or SS controls. It is possible that chemistry or microbiology of the ISS system increased deposition of inhibitory compounds on the HXOO coupon surfaces; these may inhibit inoculated species to differing degrees.

Biogeochemistry of Produced Water from Unconventional Wells in the Powder River Basin, Wyoming

NASA Astrophysics Data System (ADS)

Drogos, D. L.; Nye, C.; Quillinan, S.; Urynowicz, M. A.; Wawrousek, K.

2017-12-01

Microbial activity in waters associated with unconventional oil and gas reservoirs is poorly described but can profoundly affect management strategies for produced water (PW), frac fluids, and biocides. Improved identification of microbial communities is required to develop targeted solutions for detrimental microbial activity such as biofouling and to exploit favorable activity such as microbial induced gas production. We quantified the microbial communities and inorganic chemistry in PW samples from cretaceous formations in six unconventional oil and gas wells in the Powder River Basin in northeast Wyoming. The wells are horizontal completions in the Frontier, Niobrara, Shannon, and Turner formations at depths of 10,000 to 12,000 feet, with PW temperatures ranging from 93oF to 130oF. Biocides utilized in frac fluids primarily included glutaraldehyde and Alkyl Dimethyl Benzyl Ammonium Chloride (ADBAC), with first production occurring in 2013. Geochemical results for PW are: pH 6.5 to 6.9; alkalinity (as CaCO3) 219 to 519 ppm; salinity 13,200 to 22,300 ppm; and TDS 39,364 to 62,725 ppm. Illumina MiSeq 16S rRNA sequencing identified the majority of communities in PW are related to anaerobic, thermophilic, halophilic, chemoheterotrophic, and chemoorganotrophic bacteria, including Thermotoga, Clostridiaceae, Thermoanaerobacter, Petrotoga, Anaerobaculum, Clostridiales, Desulfomicrobium, and Halanaerobiaceae. These findings are important for identification of biogeochemical reactions that affect the organic-inorganic-microbial interactions among reservoir rocks, formation waters, and frac fluids. Better understanding of these biogeochemical reactions would allow producers to formulate frac fluids and biocides to encourage beneficial microbial phenomena such as biogenic gas production while discouraging detrimental effects such as biofouling.

Re-evaluation of temperature of replacement dolomitization in the Triassic Latemar platform with clumped isotope thermometry

NASA Astrophysics Data System (ADS)

Müller, Inigo Andreas; Rodriguez-Blanco, Juan D.; Storck, Julian-Christopher; Benning, Liane G.; Wilson, Edith N.; Brack, Peter; Bernasconi, Stefano M.

2017-04-01

The Triassic Latemar platform shows different types of dolomitization styles including features such as dolomitized zones around basaltic dykes and patchy reddish or greyish dolomitization features in the central part of the platform. The processes leading to this partial dolomitization are still debated. Different geochemical tools were applied to determine the formation temperature of the patchy dolomite phases, thereby microthermometry on fluid inclusions and clumped isotope thermometry revealed significantly different temperature ranges (100 to 200 °C vs. 40 to 80 °C, from Wilson et al., 1990 and Ferry et al., 2011, respectively). We re-evaluated the origin of these patchy dolomites at Latemar using a new dolomite-specific clumped isotope temperature calibration based on dolomites synthetized in the laboratory at different temperatures. We directly compare the clumped isotope temperatures of patchy dolomites from Latemar with those obtained on the same samples by fluid inclusion microthermometry. With the new dolomite specific clumped isotope temperature calibration it is possible to determine more precisely the dolomite formation temperature and the oxygen isotope composition of the fluid source. Both are critical parameters for better constraining the origin of different dolomite fabrics on the Earth's surface and in ancient sediments. E.N. Wilson, L.A. Hardie and O.M. Phillips, 1990. Dolomitization front geometry, fluid flow patterns, and the origin of massive dolomite: the Triassic Latemar buildup, northern Italy. American Journal of Science 290, 741-796. J.M. Ferry, B.H. Passey, C. Vasconcelos and J.M. Eiler, 2011. Formation of dolomite at 40-80 °C in the Latemar carbonate buildup, Dolomites, Italy, from clumped isotope thermometry. Geology 39, 571-574.

Moving hydrocarbons through portions of tar sands formations with a fluid

DOEpatents

Stegemeier, George Leo; Mudunuri, Ramesh Raju; Vinegar, Harold J.; Karanikas, John Michael; Jaiswal, Namit; Mo, Weijian

2010-05-18

A method for treating a tar sands formation is disclosed. The method includes heating a first portion of a hydrocarbon layer in the formation from one or more heaters located in the first portion. The heat is controlled to increase a fluid injectivity of the first portion. A drive fluid and/or an oxidizing fluid is injected and/or created in the first portion to cause at least some hydrocarbons to move from a second portion of the hydrocarbon layer to a third portion of the hydrocarbon layer. The second portion is between the first portion and the third portion. The first, second, and third portions are horizontally displaced from each other. The third portion is heated from one or more heaters located in the third portion. Hydrocarbons are produced from the third portion of the formation. The hydrocarbons include at least some hydrocarbons from the second portion of the formation.

Data science implications in diamond formation and craton evolution

NASA Astrophysics Data System (ADS)

Pan, F.; Huang, F.; Fox, P. A.

2017-12-01

Diamonds are so-called "messengers" from the deep Earth. Fluid and mineral inclusions in diamonds could reflect the compositions of fluids/melts and wall-rocks in which diamond formed. Recently many diamond samples are examined to study the water content in the mantle transition zone1, the mechanism of diamond formation2 and the mantle evolution history3. However, most of the studies can only explain local activities. Therefore, an overall project of data grouping, comparison and correlation is needed, but limited progress has been made due to a lack of benchmark datasets on diamond formation and effective computing algorithms. In this study, we start by proposing the very first complete and easily-accessible dataset on mineral and fluid inclusions in diamonds. We rescue, collect and organize the data available from papers, journals and other publications resources ([2-4] and more), and then apply several state-of-the-art machine learning methods to tackle this earth science problem by clustering diamond formation process into distinct groups primarily based on the compositions, the formation temperature and pressure, the age and so on. Our ongoing work includes further data exploration and training existing models. Our preliminary results show that diamonds formed from older cratons usually have higher formation temperature. Also peridotitic diamonds take a much larger population than the ecologitic ones. More details are being discovered when we finish constructing the database and training our model. We expect the result to demonstrate the advantages of using machine learning and data science in earth science research problems. Our methodology for knowledge discovery are very general and can be broadly applied to other earth science research problems under the same framework.[1] Pearson et al, Nature (2014); [2] Tomlinson et al, EPSL (2006); [3] Weiss et al, Nature (2016); [4] Stachel and Harris, Ore Geology Reviews (2008); Weiss et al, EPSL (2013)

Formation of amorphous calcium carbonate in caves and its implications for speleothem research.

PubMed

Demény, Attila; Németh, Péter; Czuppon, György; Leél-Őssy, Szabolcs; Szabó, Máté; Judik, Katalin; Németh, Tibor; Stieber, József

2016-12-22

Speleothem deposits are among the most valuable continental formations in paleoclimate research, as they can be dated using absolute dating methods, and they also provide valuable climate proxies. However, alteration processes such as post-depositional mineralogical transformations can significantly influence the paleoclimatic application of their geochemical data. An innovative sampling and measurement protocol combined with scanning and transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy is presented, demonstrating that carbonate precipitating from drip water in caves at ~10 °C contains amorphous calcium carbonate (ACC) that later transforms to nanocrystalline calcite. Stable oxygen isotope fractionations among calcite, ACC and water were also determined, proving that ACC is 18 O-depleted (by >2.4 ± 0.8‰) relative to calcite. This, in turn, has serious consequences for speleothem-based fluid inclusion research as closed system transformation of ACC to calcite may induce a negative oxygen isotope shift in fluid inclusion water, resulting in deterioration of the original compositions. ACC formation increases the speleothems' sensitivity to alteration as its interaction with external solutions may result in the partial loss of original proxy signals. Mineralogical analysis of freshly precipitating carbonate at the studied speleothem site is suggested in order to determine the potential influence of ACC formation.

Rock Geochemistry and Mineralogy from Fault Zones and Polymetallic Fault Veins of the Central Front Range, Colorado

USGS Publications Warehouse

Caine, Jonathan S.; Bove, Dana J.

2010-01-01

During the 2004 to 2008 field seasons, approximately 200 hand samples of fault and polymetallic vein-related rocks were collected for geochemical and mineralogical analyses. The samples were collected by the U.S. Geological Survey as part of the Evolution of Brittle Structures Task under the Central Colorado Assessment Project (CCAP) of the Mineral Resources Program (http://minerals.cr.usgs.gov/projects/colorado_assessment/index.html). The purpose of this work has been to characterize the relation between epithermal, polymetallic mineral deposits, paleostress, and the geological structures that hosted fluid flow and localization of the deposits. The data in this report will be used to document and better understand the processes that control epithermal mineral-deposit formation by attempting to relate the geochemistry of the primary structures that hosted hydrothermal fluid flow to their heat and fluid sources. This includes processes from the scale of the structures themselves to the far field scale, inclusive of the intrusive bodies that have been thought to be the sources for the hydrothermal fluid flow. The data presented in this report are part of a larger assessment effort on public lands. The larger study area spans the region of the southern Rocky Mountains in Colorado from the Wyoming to New Mexico borders and from the eastern boundary of the Front Range to approximately the longitude of Vail and Leadville, Colorado. Although the study area has had an extensive history of geological mapping, the mapping has resulted in a number of hypotheses that are still in their infancy of being tested. For example, the proximity of polymetallic veins to intrusive bodies has been thought to reflect a genetic relation between the two features; however, this idea has not been well tested with geochemical indicators. Recent knowledge regarding the coupled nature of stress, strain, fluid flow, and geochemistry warrant new investigations and approaches to test a variety of ideas regarding the genetic processes associated with ore-deposit formation. The central part of the eastern Front Range has excellent exposures of fault zones and polymetallic fault veins, subsequently resulting in some of the most detailed mapping and associated data sets in the region. Thus, the area was chosen for detailed data compilation, new sample and data collection, and a variety of structural and geochemical analyses. The data presented in this report come from samples of fault-related exposures in the Front Range and include elemental chemistry and mineralogy from the outcrop-scale study localities within the larger CCAP study area.

CO 2-induced chemo-mechanical alteration in reservoir rocks assessed via batch reaction experiments and scratch testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aman, Michael; Espinoza, D. Nicolas; Ilgen, Anastasia G.

Here, the injection of carbon dioxide (CO 2) into geological formations results in a chemical re-equilibration between the mineral assemblage and the pore fluid, with ensuing mineral dissolution and re-precipitation. Hence, target rock formations may exhibit changes of mechanical and petrophysical properties due to CO 2 exposure. We conducted batch reaction experiments with Entrada Sandstone and Summerville Siltstone exposed to de-ionized water and synthetic brine under reservoir pressure (9–10 MPa) and temperature (80°C) for up to four weeks. Samples originate from the Crystal Geyser field site, where a naturally occurring CO 2 seepage alters portions of these geologic formations. Wemore » conducted micro-scratch tests on rock samples without alteration, altered under laboratory conditions, and naturally altered over geologic time. Scratch toughness and hardness decrease as a function of exposure time and water salinity up to 52% in the case of Entrada and 87% in the case of Summerville after CO 2-induced alteration in the laboratory. Imaging of altered cores with SEM-EDS and X-ray microCT methods show dissolution of carbonate and silica cements and matrix accompanied by minor dissolution of Fe-oxides, clays, and other silicates. Parallel experiments using powdered samples confirm that dissolution of carbonate and silica are the primary reactions. The batch reaction experiments in the autoclave utilize a high fluid to rock volume ratio and represent an end member of possible alteration associated with CO 2 storage systems. These types of tests serve as a pre-screening tool to identify the susceptibility of rock facies to CO 2-related chemical-mechanical alteration during long-term CO 2 storage.« less

CO 2-induced chemo-mechanical alteration in reservoir rocks assessed via batch reaction experiments and scratch testing

DOE PAGES

Aman, Michael; Espinoza, D. Nicolas; Ilgen, Anastasia G.; ...

2017-09-22

Here, the injection of carbon dioxide (CO 2) into geological formations results in a chemical re-equilibration between the mineral assemblage and the pore fluid, with ensuing mineral dissolution and re-precipitation. Hence, target rock formations may exhibit changes of mechanical and petrophysical properties due to CO 2 exposure. We conducted batch reaction experiments with Entrada Sandstone and Summerville Siltstone exposed to de-ionized water and synthetic brine under reservoir pressure (9–10 MPa) and temperature (80°C) for up to four weeks. Samples originate from the Crystal Geyser field site, where a naturally occurring CO 2 seepage alters portions of these geologic formations. Wemore » conducted micro-scratch tests on rock samples without alteration, altered under laboratory conditions, and naturally altered over geologic time. Scratch toughness and hardness decrease as a function of exposure time and water salinity up to 52% in the case of Entrada and 87% in the case of Summerville after CO 2-induced alteration in the laboratory. Imaging of altered cores with SEM-EDS and X-ray microCT methods show dissolution of carbonate and silica cements and matrix accompanied by minor dissolution of Fe-oxides, clays, and other silicates. Parallel experiments using powdered samples confirm that dissolution of carbonate and silica are the primary reactions. The batch reaction experiments in the autoclave utilize a high fluid to rock volume ratio and represent an end member of possible alteration associated with CO 2 storage systems. These types of tests serve as a pre-screening tool to identify the susceptibility of rock facies to CO 2-related chemical-mechanical alteration during long-term CO 2 storage.« less

Low-noise humidity controller for imaging water mediated processes in atomic force microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gaponenko, I., E-mail: iaroslav.gaponenko@unige.ch; Gamperle, L.; Herberg, K.

2016-06-15

We demonstrate the construction of a novel low-noise continuous flow humidity controller and its integration with a commercial variable-temperature atomic force microscope fluid cell, allowing precise control of humidity and temperature at the sample during nanoscale measurements. Based on wet and dry gas mixing, the design allows a high mechanical stability to be achieved by means of an ultrasonic atomiser for the generation of water-saturated gas, improving upon previous bubbler-based architectures. Water content in the flow is measured both at the inflow and outflow of the fluid cell, enabling the monitoring of water condensation and icing, and allowing controlled variationmore » of the sample temperature independently of the humidity. To benchmark the performance of the controller, the results of detailed noise studies and time-based imaging of the formation of ice layers on highly oriented pyrolytic graphite are shown.« less

Negative Magnetoresistance in Viscous Flow of Two-Dimensional Electrons.

PubMed

Alekseev, P S

2016-10-14

At low temperatures, in very clean two-dimensional (2D) samples, the electron mean free path for collisions with static defects and phonons becomes greater than the sample width. Under this condition, the electron transport occurs by formation of a viscous flow of an electron fluid. We study the viscous flow of 2D electrons in a magnetic field perpendicular to the 2D layer. We calculate the viscosity coefficients as the functions of magnetic field and temperature. The off-diagonal viscosity coefficient determines the dispersion of the 2D hydrodynamic waves. The decrease of the diagonal viscosity in magnetic field leads to negative magnetoresistance which is temperature and size dependent. Our analysis demonstrates that this viscous mechanism is responsible for the giant negative magnetoresistance recently observed in the ultrahigh-mobility GaAs quantum wells. We conclude that 2D electrons in those structures in moderate magnetic fields should be treated as a viscous fluid.

Negative Magnetoresistance in Viscous Flow of Two-Dimensional Electrons

NASA Astrophysics Data System (ADS)

Alekseev, P. S.

2016-10-01

At low temperatures, in very clean two-dimensional (2D) samples, the electron mean free path for collisions with static defects and phonons becomes greater than the sample width. Under this condition, the electron transport occurs by formation of a viscous flow of an electron fluid. We study the viscous flow of 2D electrons in a magnetic field perpendicular to the 2D layer. We calculate the viscosity coefficients as the functions of magnetic field and temperature. The off-diagonal viscosity coefficient determines the dispersion of the 2D hydrodynamic waves. The decrease of the diagonal viscosity in magnetic field leads to negative magnetoresistance which is temperature and size dependent. Our analysis demonstrates that this viscous mechanism is responsible for the giant negative magnetoresistance recently observed in the ultrahigh-mobility GaAs quantum wells. We conclude that 2D electrons in those structures in moderate magnetic fields should be treated as a viscous fluid.

Capillary Thinning of Particle-laden Drops

NASA Astrophysics Data System (ADS)

Wagoner, Brayden; Thete, Sumeet; Jahns, Matt; Doshi, Pankaj; Basaran, Osman

2015-11-01

Drop formation is central in many applications such as ink-jet printing, microfluidic devices, and atomization. During drop formation, a thinning filament is created between the about-to-form drop and the fluid hanging from the nozzle. Therefore, the physics of capillary thinning of filaments is key to understanding drop formation and has been thoroughly studied for pure Newtonian fluids. The thinning dynamics is, however, altered completely when the fluid contains particles, the physics of which is not well understood. In this work, we explore the impact of solid particles on filament thinning and drop formation by using a combination of experiments and numerical simulations.

Bioactivity studies on TiO₂-bearing Na₂O-CaO-SiO₂-B₂O₃ glasses.

PubMed

Jagan Mohini, G; Sahaya Baskaran, G; Ravi Kumar, V; Piasecki, M; Veeraiah, N

2015-12-01

Soda lime silica borate glasses mixed with different concentrations of TiO2 are synthesized by the melt-quenching technique. As a part of study on bioactivity of these glasses, the samples were immersed in simulated body fluid (SBF) solution for prolonged times (~21 days) during which weight loss along with pH measurements is carried out at specific intervals of time. The XRD and SEM analyses of post-immersed samples confirm the formation of crystalline hydroxyapatite layer (HA) on the surface of the samples. To assess the role of TiO2 on the formation of HA layer and degradability of the samples the spectroscopic studies viz. optical absorption and IR spectral studies on post- and pre-immersed samples have been carried out. The analysis of the results of degradability together with spectroscopic studies as a function of TiO2 concentration indicated that about 6.0 mol% of TiO2 is the optimal concentration for achieving better bioactivity of these glasses. The presence of the maximal concentration octahedral titanium ions in this glass that facilitates the formation of HA layer is found to be the reason for such a higher bioactivity. Copyright © 2015 Elsevier B.V. All rights reserved.

Fluid sampling tool

DOEpatents

Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

2000-01-01

A fluid-sampling tool for obtaining a fluid sample from a container. When used in combination with a rotatable drill, the tool bores a hole into a container wall, withdraws a fluid sample from the container, and seals the borehole. The tool collects fluid sample without exposing the operator or the environment to the fluid or to wall shavings from the container.

Impedance loading and radiation of finite aperture multipole sources in fluid filled boreholes

NASA Astrophysics Data System (ADS)

Geerits, Tim W.; Kranz, Burkhard

2017-04-01

In the exploration of oil and gas finite aperture multipole borehole acoustic sources are commonly used to excite borehole modes in a fluid-filled borehole surrounded by a (poro-) elastic formation. Due to the mutual interaction of the constituent sources and their immediate proximity to the formation it has been unclear how and to what extent these effects influence radiator performance. We present a theory, based on the equivalent surface source formulation for fluid-solid systems that incorporates these 'loading' effects and allows for swift computation of the multipole source dimensionless impedance, the associated radiator motion and the resulting radiated wave field in borehole fluid and formation. Dimensionless impedance results are verified through a comparison with finite element modeling results in the cases of a logging while drilling tool submersed in an unbounded fluid and a logging while drilling tool submersed in a fluid filled borehole surrounded by a fast and a slow formation. In all these cases we consider a monopole, dipole and quadrupole excitation, as these cases are relevant to many borehole acoustic applications. Overall, we obtain a very good agreement.

Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

NASA Astrophysics Data System (ADS)

Ohtomo, Y.; Ijiri, A.; Ikegawa, Y.; Tsutsumi, M.; Imachi, H.; Uramoto, G.; Hoshino, T.; Morono, Y.; Tanikawa, W.; Hirose, T.; Inagaki, F.

2013-12-01

The geological CO2 sequestration into subsurface unmineable oil/gas fields and coal formations has been considered as one of the possible ways to reduce dispersal of anthropogenic greenhouse gasses into the atmosphere. However, feasibility of CO2 injection largely depends on a variety of geological and economical settings, and its ecological consequences have remained largely unpredictable. To address these issues, we developed a new flow-through-type CO2 injection system designated as the 'geobio-reactor system' to examine possible geophysical, geochemical and microbiological impact caused by CO2 injection under in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. In this study, we investigated Eocene bituminous coal-sandstones in the northwestern Pacific coast, Hokkaido, Japan, using the geobio-reactor system. Anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 mL/min, respectively) were continuously supplemented into the coal-sand column under the pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. Molecular analysis of bacterial 16S rRNA genes showed that predominant bacterial components were physically dispersed from coal to sand as the intact form during experiment. Cultivation experiments from sub-sampling fluids indicated that some terrestrial microbes could preserve their survival in subsurface condition. Molecular analysis of archaeal 16S rRNA genes also showed that no methanogens were activated during experiment. We also anaerobically incubated the coal sample using conventional batch-type cultivation technique with a medium for methanogens. After one year of the batch incubation at 20°C, methane could be detected from the cultures except for the acetate-fed culture. The sequence of archaeal 16S rRNA genes via PCR amplification obtained from the H2 plus formate-fed culture was affiliated with a hydrogenotrophic methanogen within the genus Methanobacterium, whereas the methanol plus trimethylamine culture belonged to a methylotrophic methanogen within the genus Methanosarcina. For the acetate-fed culture, no cell proliferation and methane-production were observed after two-years incubation. During the injection of CO2 and fluid, increase of dissolved CH4 concentration was observed, of which δ13CCH4 were constantly similar to those of the absorbed coal-bed methane (δ13CCBM, ~70‰), suggesting the enhanced gas recovery with fluid flow. The output volume of CO2 (ΣCO2out, 22.1 to 125.6 mM) was smaller than initial concentration (ΣCO2in, 138.38 mM), which can be explained by either adsorption on coal, formation of carbonate minerals, or microbial consumption. Increase of acetate concentration in the fluids was also observed, whereas δ13Cacetate depleted during experiment. Considering with the decrease of additive H2, it is most likely that homo-acetogenesis would occur during experiments, which is consistent with detection of Sporomusa-related 16S rRNA genes, homo-acetogenic bacterium, in cloning analysis of sandstone after experiment. Decrease of formate concentrations and increase of δ13Cformate indicate bacterial consumption of formate and isotopic fractionation. Our results suggest that CO2 injection to natural coal-sand formation stimulates homo-acetogenesis rather than methanogenesis, accompanied by biogenic CO2 conversion to acetate.

High-performance liquid chromatographic determination of histamine in biological samples: the cerebrospinal fluid challenge--a review.

PubMed

Wang, Zhaopin; Wu, Juanli; Wu, Shihua; Bao, Aimin

2013-04-24

Histamine, a neurotransmitter crucially involved in a number of basic physiological functions, undergoes changes in neuropsychiatric disorders. Detection of histamine in biological samples such as cerebrospinal fluid (CSF) is thus of clinical importance. The most commonly used method for measuring histamine levels is high performance liquid chromatography (HPLC). However, factors such as very low levels of histamine, the even lower CSF-histamine and CSF-histamine metabolite levels, especially in certain neuropsychiatric diseases, rapid formation of histamine metabolites, and other confounding elements during sample collection, make analysis of CSF-histamine and CSF-histamine metabolites a challenging task. Nonetheless, this challenge can be met, not only with respect to HPLC separation column, derivative reagent, and detector, but also in terms of optimizing the CSF sample collection. This review aims to provide a general insight into the quantitative analyses of histamine in biological samples, with an emphasis on HPLC instruments, methods, and hyphenated techniques, with the aim of promoting the development of an optimal and practical protocol for the determination of CSF-histamine and/or CSF-histamine metabolites. Copyright © 2013 Elsevier B.V. All rights reserved.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, Louis K.; Alper, Naum I.

1994-01-01

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, L.K.; Alper, N.I.

1994-11-22

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump. 1 fig.

Development and application of laser microprobe techniques for oxygen isotope analysis of silicates, and, fluid/rock interaction during and after granulite-facies metamorphism, highland southwestern complex, Sri Lanka

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elsenheimer, D.W.

1992-01-01

The extent of fluid/rock interaction within the crust is a function of crustal depth, with large hydrothermal systems common in the brittle, hydrostatically pressured upper crust, but restricted fluid flow in the lithostatically pressured lower crust. To quantify this fluid/rock interaction, a Nd-YAG/CO[sub 2] laser microprobe system was constructed to analyze oxygen isotope ratios in silicates. Developed protocols produce high precision in [sigma][sup 18]O ([+-]0.2, 1[sigma]) and accuracy comparable to conventional extraction techniques on samples of feldspar and quartz as small as 0.3mg. Analysis of sub-millimeter domains in quartz and feldspar in granite from the Isle of Skye, Scotland, revealsmore » complex intragranular zonation. Contrasting heterogeneous and homogeneous [sigma][sup 18]O zonation patterns are revealed in samples <10m apart. These differences suggest fluid flow and isotopic exchange was highly heterogeneous. It has been proposed that granulite-facies metamorphism in the Highland Southwestern Complex (HSWC), Sri Lanka, resulted from the pervasive influx of CO[sub 2], with the marbles and calc-silicates within the HSWC a proposed fluid source. The petrologic and stable isotopic characteristic of HSWC marbles are inconsistent with extensive decarbonation. Wollastonite calc-silicates occur as deformed bands and as post-metamorphis veins with isotopic compositions that suggest vein fluids that are at least in part magmatic. Post-metamorphic magmatic activity is responsible for the formation of secondary disseminated graphite growth in the HSWC. This graphite has magmatic isotopic compositions and is associated with vein graphite and amphibolite-granulite facies transitions zones. Similar features in Kerela Khondalite Belt, South India, may suggest a common metamorphic history for the two terranes.« less

Characterisation of dissolved organic compounds in hydrothermal fluids by stir bar sorptive extraction - gas chomatography - mass spectrometry. Case study: the Rainbow field (36°N, Mid-Atlantic Ridge)

PubMed Central

2012-01-01

The analysis of the dissolved organic fraction of hydrothermal fluids has been considered a real challenge due to sampling difficulties, complexity of the matrix, numerous interferences and the assumed ppb concentration levels. The present study shows, in a qualitative approach, that Stir Bar Sorptive Extraction (SBSE) followed by Thermal Desorption – Gas Chromatography – Mass Spectrometry (TD-GC-MS) is suitable for extraction of small sample volumes and detection of a wide range of volatile and semivolatile organic compounds dissolved in hydrothermal fluids. In a case study, the technique was successfully applied to fluids from the Rainbow ultramafic-hosted hydrothermal field located at 36°14’N on the Mid-Atlantic Ridge (MAR). We show that n-alkanes, mono- and poly- aromatic hydrocarbons as well as fatty acids can be easily identified and their retention times determined. Our results demonstrate the excellent repeatability of the method as well as the possibility of storing stir bars for at least three years without significant changes in the composition of the recovered organic matter. A preliminary comparative investigation of the organic composition of the Rainbow fluids showed the great potential of the method to be used for assessing intrafield variations and carrying out time series studies. All together our results demonstrate that SBSE-TD-GC-MS analyses of hydrothermal fluids will make important contributions to the understanding of geochemical processes, geomicrobiological interactions and formation of mineral deposits. PMID:23134621

Evolution of fracture and fault-controlled fluid pathways in carbonates of the Albanides fold-thrust belt

USGS Publications Warehouse

Graham, Wall B.R.; Girbacea, R.; Mesonjesi, A.; Aydin, A.

2006-01-01

The process of fracture and fault formation in carbonates of the Albanides fold-thrust belt has been systematically documented using hierarchical development of structural elements from hand sample, outcrop, and geologic-map scales. The function of fractures and faults in fluid migration was elucidated using calcite cement and bitumen in these structures as a paleoflow indicator. Two prefolding pressure-solution and vein assemblages were identified: an overburden assemblage and a remote tectonic stress assemblage. Sheared layer-parallel pressure-solution surfaces of the overburden assemblage define mechanical layers. Shearing of mechanical layers associated with folding resulted in the formation of a series of folding assemblage fractures at different orientations, depending on the slip direction of individual mechanical layers. Prefolding- and folding-related fracture assemblages together formed fragmentation zones in mechanical layers and are the sites of incipient fault localization. Further deformation along these sites was accommodated by rotation and translation of fragmented rock, which formed breccia and facilitated fault offset across multiple mechanical layers. Strike-slip faults formed by this process are organized in two sets in an apparent conjugate pattern. Calcite cement and bitumen that accumulated along fractures and faults are evidence of localized fluid flow along fault zones. By systematic identification of fractures and faults, their evolution, and their fluid and bitumen contents, along with subsurface core and well-log data, we identify northeast-southwest-trending strike-slip faults and the associated structures as dominant fluid pathways in the Albanides fold-thrust belt. Copyright ?? 2006. The American Association of Petroleum Geologists. All rights reserved.

Compositions produced using an in situ heat treatment process

DOEpatents

Roes, Augustinus Wilhelmus Maria; Nair, Vijay; Munsterman, Erwin Hunh; Van Bergen, Petrus Franciscus; Van Den Berg, Franciscus Gondulfus Antonius

2013-05-28

Methods for treating a subsurface formation and compositions produced therefrom are described herein. At least one method for producing hydrocarbons from a subsurface formation includes providing heat to the subsurface formation using an in situ heat treatment process. One or more formation particles may be formed during heating of the subsurface formation. Fluid that includes hydrocarbons and the formation particles may be produced from the subsurface formation. The formation particles in the produced fluid may include cenospheres and have an average particle size of at least 0.5 micrometers.

Compositions produced using an in situ heat treatment process

DOEpatents

Roes, Augustinus Wilhelmus Maria [Houston, TX; Nair, Vijay [Katy, TX; Munsterman, Erwin Henh [Amsterdam, NL; Van Bergen, Petrus Franciscus [Amsterdam, NL; Van Den Berg, Franciscus Gondulfus Antonius

2009-10-20

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for producing hydrocarbons from a subsurface formation includes providing heat to the subsurface formation using an in situ heat treatment process. One or more formation particles may be formed during heating of the subsurface formation. Fluid that includes hydrocarbons and the formation particles may be produced from the subsurface formation. The formation particles in the produced fluid may include cenospheres and have an average particle size of at least 0.5 micrometers.

Gas injection to inhibit migration during an in situ heat treatment process

DOEpatents

Kuhlman, Myron Ira; Vinegar; Harold J.; Baker, Ralph Sterman; Heron, Goren

2010-11-30

Methods of treating a subsurface formation are described herein. Methods for treating a subsurface treatment area in a formation may include introducing a fluid into the formation from a plurality of wells offset from a treatment area of an in situ heat treatment process to inhibit outward migration of formation fluid from the in situ heat treatment process.

Field and Lab-Based Microbiological Investigations of the Marcellus Shale

NASA Astrophysics Data System (ADS)

Wishart, J. R.; Neumann, K.; Edenborn, H. M.; Hakala, A.; Yang, J.; Torres, M. E.; Colwell, F. S.

2013-12-01

The recent exploration of shales for natural gas resources has provided the opportunity to study their subsurface geochemistry and microbiology. Evidence indicates that shale environments are marked by extreme conditions such as high temperature and pressure, low porosity, permeability and connectivity, and the presence of heavy metals and radionuclides. It has been postulated that many of these shales are naturally sterile due to the high pressure and temperature conditions under which they were formed. However, it has been shown in the Antrim and New Albany shales that microbial communities do exist in these environments. Here we review geochemical and microbiological evidence for the possible habitation of the Marcellus shale by microorganisms and compare these conditions to other shales in the U.S. Furthermore, we describe the development of sampling and analysis techniques used to evaluate microbial communities present in the Marcellus shale and associated hydraulic fracturing fluid. Sampling techniques thus far have consisted of collecting flowback fluids from wells and water impoundments and collecting core material from previous drilling expeditions. Furthermore, DNA extraction was performed on Marcellus shale sub-core with a MoBio PowerSoil kit to determine its efficiency. Assessment of the Marcellus shale indicates that it has low porosity and permeability that are not conducive to dense microbial populations; however, moderate temperatures and a natural fracture network may support a microbial community especially in zones where the Marcellus intersects more porous geologic formations. Also, hydraulic fracturing extends this fracture network providing more environments where microbial communities can exist. Previous research which collected flowback fluids has revealed a diverse microbial community that may be derived from hydrofrac fluid production or from the subsurface. DNA extraction from 10 g samples of Marcellus shale sub-core were unsuccessful even when samples were spiked with 8x108 cells/g of shale. This indicated that constituents of shale such as high levels of carbonates, humic acids and metals likely inhibited components of the PowerSoil kit. Future research is focused on refining sample collection and analyses to gain a full understanding of the microbiology of the Marcellus shale and associated flowback fluids. This includes the development of an in situ osmosampler, which will collect temporally relevant fluid and colonized substrate samples. The design of the osmosampler for hydraulic fracturing wells is being adapted from those used to sample marine environments. Furthermore, incubation experiments are underway to study interactions between microbial communities associated with hydraulic fracturing fluid and Marcellus shale samples. In conclusion, evidence suggests that the Marcellus shale is a possible component of the subsurface biosphere. Future studies will be valuable in determining the microbial community structure and function in relation to the geochemistry of the Marcellus shale and its future development as a natural gas resource.

Using geothermal energy to heat a portion of a formation for an in situ heat treatment process

DOEpatents

Pieterson, Roelof; Boyles, Joseph Michael; Diebold, Peter Ulrich

2010-06-08

Methods of using geothermal energy to treat subsurface formations are described herein. Methods for using geothermal energy to treat a subsurface treatment area containing or proximate to hydrocarbons may include producing geothermally heated fluid from at least one subsurface region. Heat from at least a portion of the geothermally heated fluid may be transferred to the subsurface treatment area to heat the subsurface treatment area. At least some hydrocarbon fluids may be produced from the formation.

Experimental study of CO2 effect on shale mechanical properties in the processes of complete strain-stress and post-failure tests

NASA Astrophysics Data System (ADS)

Wang, Y.; Ji, J.; Li, M.

2017-12-01

CO2 enhanced shale gas recovery has proved to be one of the most efficient methods to extract shale gas, and represent a mutually beneficial approach to mitigate greenhouse gas emission into the atmosphere. During the processes of most CO2 enhanced shale gas recovery, liquid CO2 is injected into reservoirs, fracturing the shale, making competitive adsorption with shale gas and displacing the shale gas at multi-scale to the production well. Hydraulic and mechanical coupling actions between the shale and fluid media are expected to play important roles in affecting fracture propagation, CO2 adsorption and shale gas desorption, multi-scale fluid flow, plume development, and CO2 storage. In this study, four reservoir shale samples were selected to carry out triaxial compression experiments of complete strain-stress and post failure tests. Two fluid media, CO2 and N2, were used to flow through the samples and produce the pore pressure. All of the above four compression experiments were conducted under the same confining and pore pressures, and loaded the axial pressure with the same loading path. Permeability, strain-stress, and pore volumetric change were measured and recorded over time. The results show that, compared to N2, CO2 appeared to lower the peak strength and elastic modulus of shale samples, and increase the permeability up two to six orders of magnitudes after the sample failure. Furthermore, the shale samples were dilated by CO2 much more than N2, and retained the volume of CO2 2.6 times more than N2. Results from this study indicate that the CO2 can embrittle the shale formation so as to form fracture net easily to enhance the shale gas recovery. Meanwhile, part of the remaining CO2 might be adsorbed on the surface of shale matrix and the rest of the CO2 be in the pore and fracture spaces, implying that CO2 can be effectively geo-stored in the shale formation.

"Smart" Magnetic Fluids Experiment Operated on the International Space Station

NASA Technical Reports Server (NTRS)

Agui, Juan H.; Lekan, Jack F.

2004-01-01

InSPACE is a microgravity fluid physics experiment that was operated on the International Space Station (ISS) in the Microgravity Science Glovebox from late March 2003 through early July 2003. (InSPACE is an acronym for Investigating the Structure of Paramagnetic Aggregates From Colloidal Emulsions.) The purpose of the experiment is to obtain fundamental data of the complex properties of an exciting class of smart materials termed magnetorheological (MR) fluids. MR fluids are suspensions, or colloids, comprised of small (micrometer-sized) superparamagnetic particles in a nonmagnetic medium. Colloids are suspensions of very small particles suspended in a liquid. (Examples of other colloids are blood, milk, and paint.) These controllable fluids can quickly transition into a nearly solid state when exposed to a magnetic field and return to their original liquid state when the magnetic field is removed. Controlling the strength of the magnetic field can control the relative stiffness of these fluids. MR fluids can be used to improve or develop new seat suspensions, robotics, clutches, airplane landing gear, and vibration damping systems. The principal investigator for InSPACE is Professor Alice P. Gast of the Massachusetts Institute of Technology (MIT). The InSPACE hardware was developed at the NASA Glenn Research Center. The InSPACE samples were delivered to the ISS in November 2002, on the Space Shuttle Endeavour, on Space Station Utilization Flight UF-2/STS113. Operations began on March 31, 2003, with the processing of three different particle size samples at multiple test parameters. This investigation focused on determining the structural organization of MR colloidal aggregates when exposed to a pulsing magnetic field. On Earth, the aggregates take the shape of footballs with spiky tips. This characteristic shape may be influenced by the pull of gravity, which causes most particles initially suspended in the fluid to sediment, (i.e., settle and collect at the bottom of the cell). In the absence of sedimentation effects on the ISS, the behavior and shape of these MR aggregate structures are dominated exclusively by magnetic and surface tension forces. The microscopic detail of these structures was imaged under two orthogonal camera views. The video was downlinked to the InSPACE team at Glenn's Telescience Support Center and to MIT and also recorded onboard the ISS on videotapes that will be brought back to the ground by the space shuttles. The study examined the effect on the structure formation by varying the magnetic field strength and pulse frequency, and particle size. Fundamental data that characterized the structure formation were obtained. InSPACE completed its last planned test run on July 2, 2003. Operations occurred on 21 days over approximately a 3-month period. Forty-one test points were completed during 26 test runs. During the initial testing, the procedures followed by the crew were modified to maximize the observation of some unexpected and interesting aggregate behavior. As a result Dr. Gast has reported on the formation of aggregate shapes that are more extended and diverse than those observed on the ground. Sheets of magnetic material folded over in a labyrinth pattern and large columnar aggregates with complex interfaces with the surrounding fluid are examples of the interesting structures that have been observed on the ISS. In light of these early findings, the understanding of the fundamental properties of MR fluids on the basis of ground-based observations may need to be reconsidered.The experiments on the ISS have provided a vast amount of video data for analysis. While this analysis is ongoing, plans are being made for additional experimental runs. For this purpose, additional hardware and cells containing samples of different magnetic particles and sizes are being fabricated for a future launch to the ISS. The InSPACE hardware will remain on orbit until this testing is completed.

Self-assembling iron oxyhydroxide/oxide tubular structures: laboratory-grown and field examples from Rio Tinto.

PubMed

Barge, Laura M; Cardoso, Silvana S S; Cartwright, Julyan H E; Doloboff, Ivria J; Flores, Erika; Macías-Sánchez, Elena; Sainz-Díaz, C Ignacio; Sobrón, Pablo

2016-11-01

Rio Tinto in southern Spain has become of increasing astrobiological significance, in particular for its similarity to environments on early Mars. We present evidence of tubular structures from sampled terraces in the stream bed at the source of the river, as well as ancient, now dry, terraces. This is the first reported finding of tubular structures in this particular environment. We propose that some of these structures could be formed through self-assembly via an abiotic mechanism involving templated precipitation around a fluid jet, a similar mechanism to that commonly found in so-called chemical gardens. Laboratory experiments simulating the formation of self-assembling iron oxyhydroxide tubes via chemical garden/chemobrionic processes form similar structures. Fluid-mechanical scaling analysis demonstrates that the proposed mechanism is plausible. Although the formation of tube structures is not itself a biosignature, the iron mineral oxidation gradients across the tube walls in laboratory and field examples may yield information about energy gradients and potentially habitable environments.

Self-assembling iron oxyhydroxide/oxide tubular structures: laboratory-grown and field examples from Rio Tinto

PubMed Central

Barge, Laura M.; Doloboff, Ivria J.; Flores, Erika; Sobrón, Pablo

2016-01-01

Rio Tinto in southern Spain has become of increasing astrobiological significance, in particular for its similarity to environments on early Mars. We present evidence of tubular structures from sampled terraces in the stream bed at the source of the river, as well as ancient, now dry, terraces. This is the first reported finding of tubular structures in this particular environment. We propose that some of these structures could be formed through self-assembly via an abiotic mechanism involving templated precipitation around a fluid jet, a similar mechanism to that commonly found in so-called chemical gardens. Laboratory experiments simulating the formation of self-assembling iron oxyhydroxide tubes via chemical garden/chemobrionic processes form similar structures. Fluid-mechanical scaling analysis demonstrates that the proposed mechanism is plausible. Although the formation of tube structures is not itself a biosignature, the iron mineral oxidation gradients across the tube walls in laboratory and field examples may yield information about energy gradients and potentially habitable environments. PMID:27956875

Multiple stages of aqueous alteration along fractures in mudstone and sandstone strata in Gale Crater, Mars

NASA Astrophysics Data System (ADS)

Yen, A. S.; Ming, D. W.; Vaniman, D. T.; Gellert, R.; Blake, D. F.; Morris, R. V.; Morrison, S. M.; Bristow, T. F.; Chipera, S. J.; Edgett, K. S.; Treiman, A. H.; Clark, B. C.; Downs, R. T.; Farmer, J. D.; Grotzinger, J. P.; Rampe, E. B.; Schmidt, M. E.; Sutter, B.; Thompson, L. M.; MSL Science Team

2017-08-01

The Mars rover Curiosity in Gale crater conducted the first-ever direct chemical and mineralogical comparisons of samples that have clear parent (unaltered) and daughter (altered) relationships. The mineralogy and chemistry of samples within and adjacent to alteration halos in a sandstone formation were established by the Chemistry and Mineralogy (CheMin) X-ray diffraction (XRD) instrument and the Alpha Particle X-ray Spectrometer (APXS), respectively. The Stimson formation sandstones unconformably overlie the Murray mudstone formation and represent the youngest stratigraphic unit explored by Curiosity to date. Aqueous alteration of the parent sandstone resulted in a loss of half of the original crystalline mineral phases and a three-fold increase in X-ray amorphous material. Aqueous fluids extensively leached Mg, Al, Mn, Fe, Ni, Zn and other elements from the parent material, decreased the pyroxene to feldspar ratio by a factor of two, introduced Ca and mixed-cation sulfates, and both passively and actively enriched the silica content. Leaching of Mg, Al, Mn, Fe, Ni and Zn and enrichment of Si and S are also observed in alteration halos in the underlying mudstone. These observations are consistent with infiltration of subsurface fluids, initially acidic and then alkaline, propagating along fractures crosscutting the Stimson sandstone and Murray mudstone. The geochemistry and mineralogy suggest a complicated diagenetic history with multiple stages of aqueous alteration under a variety of environmental conditions (e.g. both low and moderate pH). The formation of these alteration halos post-dates lithification of the sandstones and mudstones and represents one of the youngest hydrogeologic events presently known to have occurred in Gale crater.

Identification of Psychoactive Degradants of Cannabidiol in Simulated Gastric and Physiological Fluid

PubMed Central

Merrick, John; Lane, Brian; Sebree, Terri; Yaksh, Tony; O'Neill, Carol; Banks, Stan L.

2016-01-01

Abstract Introduction: In recent research, orally administered cannabidiol (CBD) showed a relatively high incidence of somnolence in a pediatric population. Previous work has suggested that when CBD is exposed to an acidic environment, it degrades to Δ9-tetrahydrocannabinol (THC) and other psychoactive cannabinoids. To gain a better understanding of quantitative exposure, we completed an in vitro study by evaluating the formation of psychoactive cannabinoids when CBD is exposed to simulated gastric fluid (SGF). Methods: Materials included synthetic CBD, Δ8-THC, and Δ9-THC. Linearity was demonstrated for each component over the concentration range used in this study. CBD was spiked into media containing 1% sodium dodecyl sulfate (SDS). Samples were analyzed using chromatography with UV and mass spectrometry detection. An assessment time of 3 h was chosen as representative of the maximal duration of exposure to gastric fluid. Results: CBD in SGF with 1% SDS was degraded about 85% after 60 min and more than 98% at 120 min. The degradation followed first-order kinetics at a rate constant of −0.031 min−1 (R2=0.9933). The major products formed were Δ9-THC and Δ8-THC with less significant levels of other related cannabinoids. CBD in physiological buffer performed as a control did not convert to THC. Confirmation of THC formation was demonstrated by comparison of mass spectral analysis, mass identification, and retention time of Δ9-THC and Δ8-THC in the SGF samples against authentic reference standards. Conclusions: SGF converts CBD into the psychoactive components Δ9-THC and Δ8-THC. The first-order kinetics observed in this study allowed estimated levels to be calculated and indicated that the acidic environment during normal gastrointestinal transit can expose orally CBD-treated patients to levels of THC and other psychoactive cannabinoids that may exceed the threshold for a physiological response. Delivery methods that decrease the potential for formation of psychoactive cannabinoids should be explored. PMID:28861485

Metabolic Potential and Activity in Fluids of the Coast Range Ophiolite Microbial Observatory, California, USA

NASA Technical Reports Server (NTRS)

Hoehler, T.; Som, S.; Schrenk, M.; McCollom, T.; Cardace, D.

2016-01-01

Metabolic potential and activity associated with hydrogen and carbon monoxide were characterized in fluids sampled from the the Coast Range Ophiolite Microbial Observatory (CROMO). CROMO consists of two clusters of science-dedicated wells drilled to varying depths up to 35m in the actively serpentinizing, Jurassic-age Coast Range Ophiolite of Northern California, along with a suite of pre-existing monitoring wells at the same site. Consistent with the fluid chemistry observed in other serpentinizing systems, CROMO fluids are highly alkaline, with pH up to 12.5, high in methane, with concentrations up 1600 micromolar, and low in dissolved inorganic carbon (DIC), with concentrations of 10's to 100's of micromolar. CROMO is conspicuous for fluid H2 concentrations that are consistently sub-micromolar, orders of magnitude lower than is typical of other systems. However, higher H2 concentrations (10's -100's of micromolar) at an earlier stage of fluid chemical evolution are predicted by, or consistent with: thermodynamic models for fluid chemistry based on parent rock composition equivalent to local peridotite and with water:rock ratio constrained by observed pH; the presence of magnetite at several wt% in CROMO drill cores; and concentrations of formate and carbon monoxide that would require elevated H2 if formed in equilibrium with H2 and DIC. Calculated Gibbs energy changes for reaction of H2 and CO in each of several metabolisms, across the range of fluid composition encompassed by the CROMO wells, range from bioenergetically feasible (capable of driving ATP synthesis) to thermodynamically unfavorable. Active consumption relative to killed controls was observed for both CO and H2 during incubation of fluids from the pre-existing monitoring wells; in incubations of freshly cored solids, consumption was only observed in one sample set (corresponding to the lowest pH) out of three. The specific metabolisms by which H2 and CO are consumed remain to be determined.

Fluid inclusion studies on the mineralized quartz-rich hydrothermal breccias and quartz veins of the Kay Tanda epithermal gold deposit, Lobo, Batangas, Philippines

NASA Astrophysics Data System (ADS)

Frias, S. M. P.; Takahashi, R.; Imai, A.; Blamey, N.

2017-12-01

The Kay Tanda epithermal deposit in Lobo, Batangas, Philippines is mainly hosted in quartz-rich hydrothermal breccia and quartz veins. These contain varying gold grades with some reaching bonanza gold grades as high as 200 ppm Au. They also contain varying amounts of base metal sulfides such as sphalerite, galena, chalcopyrite and pyrite whose abundances increase with depth. Petrographic analysis of the samples revealed different quartz textures such as colloform textures in quartz veins at shallow levels and feathery, flamboyant and mosaic textures in the matrix of hydrothermal breccias at deeper levels. These textures are indicative of boiling conditions. To elucidate the fluid conditions, fluid source, composition and processes during the formation of the deposit, fluid inclusion microthermometry, quantitative fluid inclusion gas analysis and laser Raman spectroscopy were conducted. Doubly polished thin wafers prepared from the quartz veins and quartz crystals in the matrix of hydrothermal breccias. Microthermometric analysis of primary fluid inclusions included measurements of the freezing temperature Tf, the temperature of ice melting Tm, and the homogenization temperature of the fluid phase by disappearance of vapor Th. Liquid-to-vapor (L-V) ratios are variable, thus, liquid-rich liquid-vapor inclusions and vapor-rich liquid-vapor inclusions coexist in some samples. The sizes of the primary fluid inclusions may reach 100 micrometers. The homogenization temperatures range 200 °C to 380 °C, with the mode around 250 °C to 280 °C. Salinities range from 2 to 7 wt% NaCl equivalent, with the mode around 4 to 5 wt% NaCl equivalent. Trends of the distribution of fluid inclusion populations based on their homogenization temperature and salinity suggest boiling which is consistent with the variable liquid to vapor ratios, i.e. coexistence of liquid-rich inclusions and vapor-rich inclusions.

Effect of alkali earth oxides on hydroxy-carbonated apatite nano layer formation for SiO2-BaO-CaO-Na2O-P2O5 glass system

NASA Astrophysics Data System (ADS)

Kiran, P.; Ramakrishna, V.; Shashikala, H. D.; Udayashankar, N. K.

2017-11-01

Barium soda lime phosphosilicate [(58SiO2-(32 - x)BaO- xCao-6Na2O-4P2O5 (where x = 15, 20, 25 and 30 mol%)] samples were synthesised using conventional sol-gel method at 700 °C sintering temperature. Thermal, structural properties were studied using thermo gravimetric analysis and differential thermal analysis, X-ray diffraction, scanning electron microscopy, fourier transform infrared and Raman spectroscopy. Using Raman spectra non-bridging oxygen concentrations were estimated. The hydroxy-carbonated apatite (HCA) layer formation on samples was analysed for 7 days using simulated body fluid (SBF) soaked samples. The growth of HCA layers self-assembled on the sample surface was discussed as a function of NBO/BO ratio. Results indicated that the number of Ca2+ ions released into SBF solution in dissolution process and weight loss of SB-treated samples vary with NBO/BO ratio. The changes in NBO/BO ratios were observed to be proportional to HCA forming ability of barium soda lime phosphosilicate glasses.

δ37Cl of Mid-Ocean Ridge Vent Fluids Determined by a new SIMS Method for Stable Chlorine Isotope Ratio Measurements

NASA Astrophysics Data System (ADS)

Bach, W.; Layne, G. L.; von Damm, K. L.

2002-12-01

A method has been developed for the direct determination of δ37Cl in natural fluid samples or rock leachates (pyrohydrolysis products) using Secondary Ion Mass Spectrometry (SIMS). Samples as small as 1 μl (<2 μg Cl) are simply dried by evaporation and the residual salts are then admixed with 1 mg of graphite powder and pressed into a small (1mm diameter) pellet amenable to SIMS analysis. Analyses are performed with a large format high-transmission, high-resolution ion microprobe -- the IMS 1270. Mass resolving powers of greater than 5000 are used to exclude isobaric interferences on 35Cl and 37Cl, producing an accurate and reproducible measurement of δ37Cl. Nine analyses of NIST Cl isotope standard 975a yield an external reproducibility of 0.5 ‰ (2σ ). Repeat analyses of samples are reproducible within 1 ‰ . First δ37Cl data for mid-ocean ridge hydrothermal vent fluids from three sites at EPR 9°N and the Logatchev site (MAR 15°N) have been collected. End member δ37Cl compositions for the EPR fluids are between +6.5 and +7.1 ‰ , whereas that of the Logatchev fluid is +4.6 ‰ . Together with pore waters from accretionary prisms, which are depleted in 37Cl (-2.0 to -7.7 ‰ ; Ransom et al., Geology, 23, 715-718, 1995), seawater-derived fluids in the marine environment span range in δ37Cl of 15 ‰ . This variability is remarkably large when compared to >100 analyses of continental waters (formation and oil-field waters, fresh waters, brines, etc.) that cluster around 0 ‰ with a maximum variation of only 5 ‰ . Two observations suggest that the 37Cl enriched nature of the vent fluids is not related to phase separation. (1) Laboratory experiments indicate that the Δ37Cl(vapor-brine) associated with super-critical phase separation of seawater between 420 and 450°C is small (-0.6 to 0.2 ‰ ; Magenheim, PhD Thesis, UCSD, 1995). (2) Conjugate vapor-brine pairs of boiling sampled in 1991 and 1994 at F vent (Von Damm et al. EPSL, 149, 101-111, 1997) have basically identical δ37Cl values indicating that phase separation (sub- or super-critical) does not significantly fractionate chlorine isotopes. We suggest, therefore, that the heavy Cl isotope signature of the fluids is a result of seawater-rock interaction and/or mineral precipitation rather than phase separation of seawater. However, the specific mechanisms responsible for this enrichment are not yet understood. The Cl isotope signatures of hydrothermally altered gabbros and sheeted dike rocks (δ37Cl: 0.4-3.4 ‰ ) tend to be heavier than seawater and it has been suggested that this indicates preferential uptake of 37Cl by amphibole (Magenheim et al., EPSL 131, 427-432, 1995). Amphibolitization can therefore not account for the development of the 37Cl enrichment of the fluids. Although the exact mechanisms of Cl isotope fractionation are not yet defined, our data suggest that Cl may not be a strictly conservative component in MOR hydrothermal systems.

A Framework for Fracture Network Formation in Overpressurised Impermeable Shale: Deformability Versus Diagenesis

NASA Astrophysics Data System (ADS)

Alevizos, Sotiris; Poulet, Thomas; Sari, Mustafa; Lesueur, Martin; Regenauer-Lieb, Klaus; Veveakis, Manolis

2017-03-01

Understanding the formation, geometry and fluid connectivity of nominally impermeable unconventional shale gas and oil reservoirs is crucial for safe unlocking of these vast energy resources. We present a recent discovery of volumetric instabilities of ductile materials that may explain why impermeable formations become permeable. Here, we present the fundamental mechanisms, the critical parameters and the applicability of the novel theory to unconventional reservoirs. We show that for a reservoir under compaction, there exist certain ambient and permeability conditions at which diagenetic (fluid-release) reactions may provoke channelling localisation instabilities. These channels are periodically interspersed in the matrix and represent areas where the excess fluid from the reaction is segregated at high velocity. We find that channelling instabilities are favoured from pore collapse features for extremely low-permeability formations and fluid-release diagenetic reactions, therefore providing a natural, periodic network of efficient fluid pathways in an otherwise impermeable matrix (i.e. fractures). Such an outcome is of extreme importance the for exploration and extraction phases of unconventional reservoirs.

Geochemical monitoring of drilling fluids; A powerful tool to forecast and detect formation waters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vuataz, F.D.; Brach, M.; Criaud, A.

1990-06-01

This paper describes a method based on the difference between the chemical compositions of formation and drilling fluids for analyzing drilling mud to forecast fluid-producing zones. The method was successfully applied in three boreholes in crystalline rocks in France. Subsequent geophysical logs and hydraulic tests confirmed the occurrence of flowing fractures.

The influence of solution composition and grain boundaries on the replacement of calcite by dolomite

NASA Astrophysics Data System (ADS)

Moraila Martinez, Teresita de Jesus; Putnis, Christine V.; Putnis, Andrew

2016-04-01

Dolomite formation is a mineral replacement reaction that affects extensive rock volumes and comprises a large fraction of oil and gas reservoirs [1,2]. The most accepted hypothesis is the 'dolomitization' of limestone by Mg-rich fluids [3]. The objective of this research is to study the replacement mechanism of calcite by dolomite, the role of grain boundaries, highlighted by Etschmann et al. (2014), and the possible influence of solutions in dolomite formation under the presence of ions that are normally in crustal aqueous fluids. To accomplish this purpose, we performed hydrothermal experiments using Carrara marble cubes of ~1.5 mm size and 7-9 mg weight as starting material, reacted with 1M (Mg,Ca)Cl2 aqueous solutions, with Mg/Ca ratios of 3 and 5 at 200°C, for different reaction times. Additional experiments were performed adding 1mM of Na2SO4, NaCl or NaF to the previous solutions. After the reaction, the product phases were identified using Raman spectroscopy, X-Ray powder diffraction (XRD), electron microprobe analysis (EMPA), and the textural evolution was studied by scanning electron microscopy (SEM). Samples reacted with aqueous solutions resulted in the replacements of the calcite rock into magnesite and dolomite. The amount and type of reaction strongly depends on the Mg/Ca ratio. Samples reacted with a Mg/Ca ratio of 5 resulted in an almost complete replacement reaction and more favorable for magnesite formation than for dolomite. When the Mg/Ca ratio was 3 dolomite formed but the replacement was located in the core of the sample. We show that grain boundaries are very important for the infiltration of solution and the progress of a replacement reaction, acting as fluid pathways. Solution composition controls the nature of the replacement product. Acknowledgment: This work is funded within a Marie Curie EU Initial Training Network- CO2-React. 1. Etschmann B., Brugger J., Pearce M.A., Ta C., Brautigan D., Jung M., Pring A. (2014). Grain boundaries as microreactors during reactive fluid flow: experimental dolomitization of a calcite marble. Contributions to Mineralogy and Petrology. 168:1045. 2. Jonas L., Müller T., Dohmen R., Baumgartner L., Putlitz B. (2015). Transport-controlled hydrothermal replacement of calcite by Mg-carbonates. Geology. doi:10.1130/G36934.1 3. Kaczmarek S.E., Sibley D.F., (2011). On the evolution of dolomite stoichiometry and cation order during high-temperature synthesis experiments: An alternative model for geochemical evolution of natural dolomites. Sedimentary Geology. 246, 30-40.

Numerical modeling of fluid and electrical currents through geometries based on synchrotron X-ray tomographic images of reservoir rocks using Avizo and COMSOL

NASA Astrophysics Data System (ADS)

Bird, M. B.; Butler, S. L.; Hawkes, C. D.; Kotzer, T.

2014-12-01

The use of numerical simulations to model physical processes occurring within subvolumes of rock samples that have been characterized using advanced 3D imaging techniques is becoming increasingly common. Not only do these simulations allow for the determination of macroscopic properties like hydraulic permeability and electrical formation factor, but they also allow the user to visualize processes taking place at the pore scale and they allow for multiple different processes to be simulated on the same geometry. Most efforts to date have used specialized research software for the purpose of simulations. In this contribution, we outline the steps taken to use commercial software Avizo to transform a 3D synchrotron X-ray-derived tomographic image of a rock core sample to an STL (STereoLithography) file which can be imported into the commercial multiphysics modeling package COMSOL. We demonstrate that the use of COMSOL to perform fluid and electrical current flow simulations through the pore spaces. The permeability and electrical formation factor of the sample are calculated and compared with laboratory-derived values and benchmark calculations. Although the simulation domains that we were able to model on a desk top computer were significantly smaller than representative elementary volumes, and we were able to establish Kozeny-Carman and Archie's Law trends on which laboratory measurements and previous benchmark solutions fall. The rock core samples include a Fountainebleau sandstone used for benchmarking and a marly dolostone sampled from a well in the Weyburn oil field of southeastern Saskatchewan, Canada. Such carbonates are known to have complicated pore structures compared with sandstones, yet we are able to calculate reasonable macroscopic properties. We discuss the computing resources required.

Fracture Fluid Additive and Formation Degradations

EPA Pesticide Factsheets

This presentation is on reactions that describe the degradation of fracturing fluids & formations during the hydraulic fracturing process & the clean‐up period. It contains a description of primary chemical reaction controls, & common degradation reactions

Investigation of bioactive CaO-P2O5-MgO-SiO2 ceramic composition for orthopedic applications

NASA Astrophysics Data System (ADS)

Kaur, Pardeep; Singh, K. J.; Sood, Henna; Arora, Daljit Singh

2017-05-01

Bioactive sample of the composition 41CaO-8P2O5-17MgO-34SiO2 has been prepared in the laboratory by quick alkali mediated sol-gel method. 1M ammonia solution has been used to form the gel. Bioactivity of the sample has been analyzed by soaking the samples in simulated body fluid. Degradation study has also undertaken to check the degradation behavior of the sample. MTT cytotoxic test has also been done to know the toxicity of the sample and results show that samples has good percentage of cell viability in the cell culture media. Formation of the hydroxyapatite has been confirmed by the XRD, Raman spectroscopy and FESEM-EDX study.

Immiscibility of Fluid Phases at Magmatic-hydrothermal Transition: Formation of Various PGE-sulfide Mineralization for Layered Basic Intrusions

NASA Astrophysics Data System (ADS)

Zhitova, L.; Borisenko, A.; Morgunov, K.; Zhukova, I.

2007-12-01

Fluid inclusions in quartz of the Merensky Reef (Bushveld Complex, South Africa) and the Chineisky Pluton (Transbaikal Region, Russia) were studied using cryometry, microthermometry, Raman-spectroscopy, LA ICP- MS, scanning electronic microscopy, gas-chromatography and isotopic methods. This allowed us to document some examples of fluid phase separation resulting in formation of different types of PGE-sulfide mineralization for layered basic intrusions. The results obtained show at least three generations of fluid separated from boiling residual alumosilicate intercumulus liquid of the Merensky Reef. The earliest fluid phase composed of homogenous high-dense methane and nitrogen gas mixture was identified in primary gas and co-existing anomalous fluid inclusions from symplectitic quartz. The next generation, heterophase fluid, composed of brines containing a free low-dense (mostly of carbon dioxide) gas phase, was observed in primary multiphase and coexisting gas-rich inclusions of miarolitic quartz crystals. The latest generation was also a heterophase fluid (low salinity water-salt solution and free low-dense methane gas phase) found in primary water-salt and syngenetic gas inclusions from peripheral zones of miarolitic quartz crystals. For the Chineisky Pluton reduced endocontact magmatogene fluids changed to oxidized low salinity hydrothermal fluids in exocontact zone. This resulted in formation of sulfide-PGE enrichment marginal zones of intrusion. The results obtained give us a possibility to suggest that: 1) Fluid phase separation is a typical feature of magmatogene fluids for layered basic intrusions. 2) Reduced fluids can extract and transport substantial PGE and sulfide concentrations. 3) Oxidation of reduced fluids is one of the most important geochemical barriers causing abundant PGE minerals and sulfides precipitation. This in turn results in both formation of PGE reefs or enriched contact zones of layered basic intrusions. This work was supported by the Ministry for Russian Science and Education, Grant DSP.2.1.1.702, by RFBR Grants ## 07-05-00685, 07-05-00803, Grant VMTK-2007 IGM SB RAS.

Characterization of fluids and fluid-fluid interaction by fiber optic refractive index sensor measurements

NASA Astrophysics Data System (ADS)

Schmidt-Hattenberger, C.; Weiner, M.; Liebscher, A.; Spangenberg, E.

2009-04-01

A fiber optic refractive index sensor is tested for continuous monitoring of fluid-fluid and fluid-gas interactions within the frame of laboratory investigations of CO2 storage, monitoring and safety technology research (COSMOS project, "Geotechnologien" program). The sensor bases on a Fabry-Perot white light interferometer technique, where the refractive index (RI) of the solution under investigation is measured by variation of the liquid-filled Fabry-Perot optical cavity length. Such sensor system is typically used for measuring and controlling oil composition and also fluid quality. The aim of this study is to test the application of the fiber optic refractive index sensor for monitoring the CO2 dissolution in formation fluids (brine, oil, gas) of CO2 storage sites. Monitoring and knowledge of quantity and especially rate of CO2 dissolution in the formation fluid is important for any assessment of long-term risks of CO2 storage sites. It is also a prerequisite for any precise reservoir modelling. As a first step we performed laboratory experiments in standard autoclaves on a variety of different fluids and fluid mixtures (technical alcohols, pure water, CO2, synthetic brines, natural formation brine from the Ketzin test site). The RI measurements are partly combined with default electrical conductivity and sonic velocity measurements. The fiber optic refractive index sensor system allows for RI measurements within the range 1.0000 to 1.7000 RI with a resolution of approximately 0.0001 RI. For simple binary fluid mixtures first results indicate linear relationships between refractive indices and fluid composition. Within the pressure range investigated (up to 60 bar) the data suggest only minor changes of RI with pressure. Further, planned experiments will focus on the determination of i) the temperature dependency of RI, ii) the combined effects of pressure and temperature on RI, and finally iii) the kinetics of CO2 dissolution in realistic formation fluids.

The geochemical controls on vent fluids from the Lucky Strike vent field, Mid-Atlantic Ridge

NASA Astrophysics Data System (ADS)

Von Damm, K. L.; Bray, A. M.; Buttermore, L. G.; Oosting, S. E.

1998-08-01

Hydrothermal vent fluids were collected from the Lucky Strike site at 37°17'N on the Mid-Atlantic Ridge in both 1993 and 1996. Seven vents were sampled with the DSV Alvin in 1993 and six vents were sampled in 1996 using the ROV Jason during the LUSTRE '96 Cruise. As three of the vents were sampled in both 1993 and in 1996, a time series of vent fluid chemistry is also reported. Measured temperatures ranged from 202 to 333°C at the 1618-1726 m depth of the vent field, which is located on Lucky Strike Seamount. These fluids are either equal to or less than the local bottom seawater in chlorinity. While the range in fluid compositions at Lucky Strike is generally within that observed elsewhere, the unusual aspects of the fluid chemistries are the relatively high pH and low Fe, Mn, Li and Zn. We attribute this, as well as an usually low Sr/Ca ratio, to reaction with a highly altered substrate. The high Si and Cu contents suggest a deep, as well as hot, source for these fluids. The fluid compositions therefore suggest formation by super-critical phase separation at a depth not less than 1300 m below the seafloor, and reaction with a relatively oxic, and previously altered, substrate. There is temporal variability in some of the vent fluid compositions as Li, K, Ca and Fe concentrations have increased in some of the vents, as has the Fe/Mn (molar) ratio, although the chlorinities have remained essentially constant from 1993 to 1996. While there is not a simple relationship between vent fluid compositions (or temperatures) and distance from the lava lake at the summit of the seamount, the vent fluids from many of the vents can be shown to be related to others, often at distances >200 m. The most southeasterly vents (Eiffel Tower and the Marker/Mounds vents) are distinct in chlorinity and other chemical parameters from the rest of the vents, although closely related to each other within the southeastern area. Similarly all of the vents not in this one area, appear closely related to each other. This suggests one or two source fluids for many of the vents, as is also inferred to be the case at TAG, but which is in contrast to observations on faster spreading ridges. This may suggest inherently different plumbing for hydrothermal systems at slower versus faster spreading ridges.

In situ conversion process utilizing a closed loop heating system

DOEpatents

Sandberg, Chester Ledlie [Palo Alto, CA; Fowler, Thomas David [Houston, TX; Vinegar, Harold J [Bellaire, TX; Schoeber, Willen Jan Antoon Henri

2009-08-18

An in situ conversion system for producing hydrocarbons from a subsurface formation is described. The system includes a plurality of u-shaped wellbores in the formation. Piping is positioned in at least two of the u-shaped wellbores. A fluid circulation system is coupled to the piping. The fluid circulation system is configured to circulate hot heat transfer fluid through at least a portion of the piping to form at least one heated portion of the formation. An electrical power supply is configured to provide electrical current to at least a portion of the piping located below an overburden in the formation to resistively heat at least a portion of the piping. Heat transfers from the piping to the formation.

Isotopic studies of authigenic sulfides, silicates and carbonates, and calcite and pyrite veinlets in the Creede Formation, San Juan Mountains, Southwest Colorado

USGS Publications Warehouse

Bethke, Philip M.; Rye, Robert O.; Finkelstein, David B.

2000-01-01

Sulfur isotope analysis of authigenic pyrite in the Creede Formation documents its precipitation by the reaction between iron in the volcaniclastic sediments and H2S formed through bacteriogenic reduction of sulfate added to the lake during and immediately following repeated volcanic eruptions during sedimentation. Pyrite veinlets in the underlying Snowshoe Mountain Tuff were formed by the percolation of H2S-bearing pore waters into fractures in the tuff. Conventional analyses of bulk samples of authigenic pyrite range from -20.4% to 34.5% essentially equivalent to the range of -30% to 40% determined using SHRIMP microprobe techniques. Conventional analyses of bulk samples of pyrite from veinlets in the Snowshow Mountain Tiff range from -3.5% to 17.6% much more limited than the ranges of -23% to 111% and -15.6% to 67.0% determined by SHRIMP and laser ablation microbeam techniques, respectively. The extreme range of δ34S for the veinlets is interpreted to be the result of continued fractionation of the already 34S-depleted pore water. Oxygen isotope analysis of authigenic smectite, kaolinite, and K-feldspar together with fluid-inclusion temperatures and oxygen isotope analysis of calcite coexisting with kaolinite indicate that the smectites formed early during burial diagenesis, in accord with petrographic observations. The 40Ar/39Ar dating of K-feldspar, concorfance of K-feldspar, kaolinite, and calcite δ18O values, and fluid-inclusion temperatures in calcite, indicate that the sediments at core hole CCM-1 were subjected to a hydrothermal event at 17.6 Ma. The minerals formed oxygen-shifted meteoric waters with δ18O values of ~-9% Smecities at CCM-1 at least partially exchanged with these waters. Carbon and oxygen isotope analysis of authigenic calcites in the Creede Formation show that they formed over a wide range of temperatures from fluids having a wide range of isotopic composition, presumably over an extended period time. Some of the cements apparently formed very late from unexchanged meteoric water. Concretions and possibly some cements at CCM-1 appear to have exchanged with the 17.6 Ma oxygen-shifted hydrothermal fluids. Such exchange is consistent with evidence that lacustrine carbonates at CCM-1 exchanged with low 18O waters, whereas those at CCM-2 underwent little, if any, exchange. The δ13C-δ18O values for calcite veinlets in the Creede Formation are similar to those for authegenic calcites. Fluid-inclusion temperatures and δ18O indicate that some were deposited during the 17.6 Ma hydrothermal event and others from unexchanged meteoric water at a later date. The isotope studies confirm that part of the model of Rye et al., proposing that the barites in the southern end of the Creede Mining District were formed by mixing of the Creede hydrotermal system with Lake Creede pore of lake waters. The silicate and carbonate isotope data indicate that the pores of the Creede Formation were occupied by at least three isotopically distinct water since the time of deposition. The original pore fluids were probably shifted to lower δ18O values during burial diagensis as a result of the hydrolysis of the volcanic glass to for smectites and other hydrous silicates. During or prior to a 17.6 Ma hydrothermal event in the vicinity of CCM-1, the Creede Formation was flushed with oxygen-shifted meteoric water, possibly related to the breaching of the east side of the caldera wall sometime between 20 and 22 Ma. Later, the Creede Formation was again flushed, this time with unexchanged meteoric water with δD-δ18O values of present-day waters, possibly during the incision of the Rio Grande drainage during uplifting of the southern Rocky Mountains beginning about 5 Ma.

Time-dependent deformation of gas shales - role of rock framework versus reservoir fluids

NASA Astrophysics Data System (ADS)

Hol, Sander; Zoback, Mark

2013-04-01

Hydraulic fracturing operations are generally performed to achieve a fast, drastic increase of permeability and production rates. Although modeling of the underlying short-term mechanical response has proven successful via conventional geomechanical approaches, predicting long-term behavior is still challenging as the formation interacts physically and chemically with the fluids present in-situ. Recent experimental work has shown that shale samples subjected to a change in effective stress deform in a time-dependent manner ("creep"). Although the magnitude and nature of this behavior is strongly related to the composition and texture of the sample, also the choice of fluid used in the experiments affects the total strain response - strongly adsorbing fluids result in more, recoverable creep. The processes underlying time-dependent deformation of shales under in-situ stresses, and the long-term impact on reservoir performance, are at present poorly understood. In this contribution, we report triaxial mechanical tests, and theoretical/thermodynamic modeling work with the aim to identify and describe the main mechanisms that control time-dependent deformation of gas shales. In particular, we focus on the role of the shale solid framework versus the type and pressure of the present pore fluid. Our experiments were mainly performed on Eagle Ford Shale samples. The samples were subjected to cycles of loading and unloading, first in the dry state, and then again after equilibrating them with (adsorbing) CO2 and (non-adsorbing) He at fluid pressures of 4 MPa. Stresses were chosen close to those persisting under in-situ conditions. The results of our tests demonstrate that likely two main types of deformation mechanisms operate that relate to a) the presence of microfractures as a dominating feature in the solid framework of the shale, and b) the adsorbing potential of fluids present in the nanoscale voids of the shale. To explain the role of adsorption in the observed compaction creep, we postulate a serial coupling between 1) stress-driven desorption of the fluid species, 2) diffusion of the desorbed species out of the solid, and 3) consequent shrinkage. We propose a model in which the total shrinkage of the solid (Step 3) that is measured as bulk compaction, is driven by a change in stress state (Step 1), and evolves in time controlled by the diffusion characteristics of the system (Step 2). Our experimental and modeling study shows that both the nature of the solid framework of the shale, as well as the type and pressure of pore fluids affect the long-term in-situ mechanical behavior of gas shale reservoirs.

Incidence, risk factors and clinical course of pancreatic fluid collections in acute pancreatitis.

PubMed

Cui, Mei Lan; Kim, Kook Hyun; Kim, Ho Gak; Han, Jimin; Kim, Hyunsoo; Cho, Kwang Bum; Jung, Min Kyu; Cho, Chang Min; Kim, Tae Nyeun

2014-05-01

Acute pancreatitis is an acute inflammatory process of the pancreas with variable involvement of other regional tissues or remote organ systems. Acute fluid collections and pseudocyst formation are the most frequent complications of acute pancreatitis. The aims of this study were to evaluate the incidence, risk factors, and clinical course of pancreatic fluid collections and pseudocyst formation following acute pancreatitis. A prospective multicenter study was conducted in five participating centers with 302 patients diagnosed with acute pancreatitis from January 2011 to July 2012. The incidence of pancreatic fluid collections and pseudocyst was 42.7 and 6.3 %, respectively. Patients with fluid collections were significantly younger, compared to those without fluid collections (51.5 ± 15.9 vs. 60.4 ± 16.5 years, P = 0.000). The proportion of alcoholic etiology (54.3 %) in patients with fluid collections was significantly higher compared to other etiologies (P = 0.000). C-reactive protein (CRP) (48 h) was significantly higher in patients with fluid collections, compared to patients without fluid collections (39.2 ± 77.4 vs. 15.1 ± 36.2 mg/dL, P = 0.016). LDH (48 h) was significantly higher in patients with pseudocyst formation, compared to patients with complete resolution (1,317.6 ± 706.4 vs. 478.7 ± 190.5 IU/L, P = 0.000). Pancreatic fluid collections showed spontaneous resolution in 69.8 % (90/129) and 84.2 % of the pseudocysts disappeared or decreased in size during follow up. Age, CRP (48 h), and alcohol etiology are risk factors for pancreatic fluid collections. LDH (48 h) appears to be a risk factor for pseudocyst formation. Most pseudocysts showed a decrease in size or spontaneous resolution with conservative management.

Genesis of the Abu Marawat gold deposit, central Eastern Desert of Egypt

NASA Astrophysics Data System (ADS)

Zoheir, Basem A.; Akawy, Ahmed

2010-06-01

Gold mineralisation at the Abu Marawat mine, central Eastern Desert of Egypt, is related to a system of massive and sheared, milky quartz veins cutting a sequence of Neoproterozoic island arc metavolcanic/volcaniclastic rocks and related banded iron formation (BIF). Sulphide-bearing quartz veins and related hydrothermal breccia bodies display a range of textures including sheared, boudinaged and recrystallised quartz, open space filling and microbreccia. These variable textures imply a complex history of crack-seal mechanism characterising the relation between mineral deposition and a major N-S-trending shear zone, during a late brittle-ductile deformation event which affected the area at about 550 Ma. Gold-base metal mineralisation is associated with brecciation and fracturing of the iron ore bands, close to silicified shears and related quartz veins. The auriferous quartz lodes are characterised by the occurrence of visible pyrite-chalcopyrite ± pyrrhotite ± sphalerite ± galena mineralisation. Gold is refractory in pyrite and chalcopyrite, but rare visible gold/electrum and telluride specks were observed in a few samples. Hydrothermal alteration includes pervasive silicification, pyritisation, sericitisation, carbonatisation confined to a delicate set of veins and altered shears, and a more widespread propylitic alteration assemblage (quartz + chlorite + pyrite + calcite ± epidote). Fluid inclusion petrography and microthermometric studies suggest heterogeneous trapping of a low-salinity (1.4-6.7 wt.% eq. NaCl) aqueous solution and a carbonic fluid. Evidence for fluid immiscibility during ore formation includes variable liquid/vapour ratios in inclusions along individual trails and bulk inclusion homogenisation into liquid and occasionally to vapour at comparable temperatures. The trapping conditions of intragranular aqueous-carbonic inclusions approximate 264-378 °C at 700-1300 bar. Similar temperature estimates have been obtained from Al-in-chlorite geothermometry of chlorite associated with sulphides in the mineralised quartz veins. Fracturing enhanced fluid circulation through the wallrock and related BIF, allowing reaction of the S-bearing ore fluid with iron oxides. This caused pyrite formation and concomitant Au precipitation, enhanced by fluid immiscibility as H 2S partitioned preferentially into the carbonic phase. The ore fluids may have originated from granitoid intrusions (likely the post-Hammamat felsites, whereas gold and base metals might have been leached from the Abu Marawat basic metavolcanics.

Ore-forming fluid system of bauxite in WZD area of northern Guizhou province, China

NASA Astrophysics Data System (ADS)

Cui, Tao

2017-12-01

The ore-forming fluid system of bauxite in Wuchuan-Zheng,an-Daozhen (short for WZD) Area of northern Guizhou Province was studied from the perspective of deposit formation mechanism. It was discovered that ore-forming fluids were mainly effective for transporting and leaching during the formation of bauxite. The means of transport mainly included colloidal transport, suspended transport and gravity flow transport. In the course of their leaching, fluids had a range of chemical reactions, as a result of which elements such as silicon and iron migrated downwards. In this process, properties of fluids changed as well.

BAT3 Analyzer: Real-Time Data Display and Interpretation Software for the Multifunction Bedrock-Aquifer Transportable Testing Tool (BAT3)

USGS Publications Warehouse

Winston, Richard B.; Shapiro, Allen M.

2007-01-01

The BAT3 Analyzer provides real-time display and interpretation of fluid pressure responses and flow rates measured during geochemical sampling, hydraulic testing, or tracer testing conducted with the Multifunction Bedrock-Aquifer Transportable Testing Tool (BAT3) (Shapiro, 2007). Real-time display of the data collected with the Multifunction BAT3 allows the user to ensure that the downhole apparatus is operating properly, and that test procedures can be modified to correct for unanticipated hydraulic responses during testing. The BAT3 Analyzer can apply calibrations to the pressure transducer and flow meter data to display physically meaningful values. Plots of the time-varying data can be formatted for a specified time interval, and either saved to files, or printed. Libraries of calibrations for the pressure transducers and flow meters can be created, updated and reloaded to facilitate the rapid set up of the software to display data collected during testing with the Multifunction BAT3. The BAT3 Analyzer also has the functionality to estimate calibrations for pressure transducers and flow meters using data collected with the Multifunction BAT3 in conjunction with corroborating check measurements. During testing with the Multifunction BAT3, and also after testing has been completed, hydraulic properties of the test interval can be estimated by comparing fluid pressure responses with model results; a variety of hydrogeologic conceptual models of the formation are available for interpreting fluid-withdrawal, fluid-injection, and slug tests.

Laboratory simulations of acid-sulfate weathering under volcanic hydrothermal conditions: Implications for early Mars.

PubMed

Marcucci, Emma C; Hynek, Brian M

2014-03-01

We have completed laboratory experiments and thermochemical equilibrium models to investigate secondary mineral formation under conditions akin to volcanic, hydrothermal acid-sulfate weathering systems. Our research used the basaltic mineralogy at Cerro Negro Volcano, Nicaragua, characterized by plagioclase, pyroxene, olivine, and volcanic glass. These individual minerals and whole-rock field samples were reacted in the laboratory with 1 molal sulfuric acid at varying temperatures (65, 150, and 200°C), fluid:rock weight ratios (1:1, 4:1, and 10:1), and durations (1-60 days). Thermochemical equilibrium models were developed using Geochemist's Workbench. To understand the reaction products and fluids, we employed scanning electron microscopy/energy dispersive spectroscopy, X-ray diffraction, and inductively coupled plasma-atomic emission spectroscopy. The results of our experiments and models yielded major alteration minerals that include anhydrite, natroalunite, minor iron oxide, and amorphous Al-Si gel. We found that variations in experimental parameters did not drastically change the suite of minerals produced; instead, abundance, size, and crystallographic shape changed. Our results also suggest that it is essential to separate phases formed during experiments from those formed during fluid evaporation to fully understand the reaction processes. Our laboratory reacted and model predicted products are consistent with the mineralogy observed at places on Mars. However, our results indicate that determination of the formation conditions requires microscopic imagery and regional context, as well as a thorough understanding of contributions from both experiment precipitation and fluid evaporation minerals.

Laboratory simulations of acid-sulfate weathering under volcanic hydrothermal conditions: Implications for early Mars

PubMed Central

Marcucci, Emma C; Hynek, Brian M

2014-01-01

We have completed laboratory experiments and thermochemical equilibrium models to investigate secondary mineral formation under conditions akin to volcanic, hydrothermal acid-sulfate weathering systems. Our research used the basaltic mineralogy at Cerro Negro Volcano, Nicaragua, characterized by plagioclase, pyroxene, olivine, and volcanic glass. These individual minerals and whole-rock field samples were reacted in the laboratory with 1 molal sulfuric acid at varying temperatures (65, 150, and 200°C), fluid:rock weight ratios (1:1, 4:1, and 10:1), and durations (1–60 days). Thermochemical equilibrium models were developed using Geochemist's Workbench. To understand the reaction products and fluids, we employed scanning electron microscopy/energy dispersive spectroscopy, X-ray diffraction, and inductively coupled plasma-atomic emission spectroscopy. The results of our experiments and models yielded major alteration minerals that include anhydrite, natroalunite, minor iron oxide, and amorphous Al-Si gel. We found that variations in experimental parameters did not drastically change the suite of minerals produced; instead, abundance, size, and crystallographic shape changed. Our results also suggest that it is essential to separate phases formed during experiments from those formed during fluid evaporation to fully understand the reaction processes. Our laboratory reacted and model predicted products are consistent with the mineralogy observed at places on Mars. However, our results indicate that determination of the formation conditions requires microscopic imagery and regional context, as well as a thorough understanding of contributions from both experiment precipitation and fluid evaporation minerals. PMID:26213665

Mantle Metasomatism under Island Arcs, Magnetic Implications

NASA Astrophysics Data System (ADS)

Friedman, S. A.; Ferre, E. C.; Arai, S.

2013-12-01

The wedge of upper mantle beneath oceanic and island arcs receives an abundant flux of fluids derived from dehydration of subducted slabs. These fluids may cause metasomatism, serpentinization or partial melting at increasing distance from the trench. Each one of these processes profoundly modifies the oxygen fugacity, mineral assemblage, rheology and seismic properties of mantle rocks. Mantle xenoliths in arcs are relatively rare compared to other tectonic settings yet, due to their rapid ascent, they provide the best record of mantle rocks at depth. Previous studies on the metasomatism of the arc mantle wedge focused on the geochemistry and mineralogy of these xenoliths. Here we present new rock magnetic and paleomagnetic results to track changes in the magnetic assemblage of mantle peridotites. Peridotites undergo a wide range of fluid-reactions that involve formation of magnetically remanent phases such as magnetite, maghemite, hematite or monosulfide solutions. Samples for this study originate from three localities displaying different degrees of metasomatism: a) Five samples from Ichinomegata crater, Megata volcano, in NE Japan are characteristically lherzolitic with metasomatic pargasite present; b) Six samples from Kurose, Hakata Bay, in SW Japan are mainly harzburgites that contain rare, late stage metasomatic sulfides; and c) Ten samples from the Iraya volcano, Batan Island, in the Philippines are lherzolites, harzburgites, and dunites that contain metasomatic olivine, orthopyroxene, clinopyroxene and pargasite. Both remanent and induced magnetizations of these mantle peridotites exhibit systematic variations as a function of the degrees of metasomatism. The contribution of these mantle peridotites to long wavelength magnetic anomalies might be significant.

Evaluation of Bacteriological and Chemical Quality of Dialysis Water and Fluid in Isfahan, Central Iran

PubMed Central

SHAHRYARI, Ali; NIKAEEN, Mahnaz; HATAMZADEH, Maryam; VAHID DASTJERDI, Marzieh; HASSANZADEH, Akbar

2016-01-01

Background: Chemical and microbial quality of water used in hemodialysis play key roles in a number of dialysis-related complications. In order to avoid the complications and to guarantee safety and health of patients therefore, vigorous control of water quality is essential. The objective of present study was to investigate the chemical and bacteriological characteristics of water used in dialysis centers of five hospitals in Isfahan, central Iran. Methods: A total of 30 water samples from the input of dialysis purification system and dialysis water were analyzed for chemical parameters. Heterotrophic plate count and endotoxin concentration of drinking water, dialysis water and dialysis fluid of 40 machines were also monitored over a 5-month period in 2011–2012. Results: Concentration of the determined chemicals (copper, zinc, sulfate, fluoride, chloramines and free chlorine) did not exceed the recommended concentration by the Association for the Advancement of Medical Instrumentation (AAMI) exclude lead, nitrate, aluminum and calcium. Furthermore, the magnesium; cadmium and chromium concentration exceeded the maximum level in some centers. No contamination with heterotrophic bacteria was observed in all samples, while the AMMI standard for endotoxin level in dialysis fluid (<2 EU/ml) was achieved in 95% of samples. Conclusion: Dialysis water and fluid failed to meet the all chemical and bacteriological requirements for hemodialysis. To minimize the risk of contaminants for hemodialysis patients therefore, a water quality management program including monitoring, maintenance and development of water treatment system in hemodialysis centers is extremely important. In addition, an appropriate disinfection program is needed to guarantee better control of bacterial growth and biofilm formation. PMID:27398338

Physical, chemical and mineralogical evolution of the Tolhuaca geothermal system, southern Andes, Chile: Insights into the interplay between hydrothermal alteration and brittle deformation

NASA Astrophysics Data System (ADS)

Sanchez-Alfaro, Pablo; Reich, Martin; Arancibia, Gloria; Pérez-Flores, Pamela; Cembrano, José; Driesner, Thomas; Lizama, Martin; Rowland, Julie; Morata, Diego; Heinrich, Christoph A.; Tardani, Daniele; Campos, Eduardo

2016-09-01

In this study, we unravel the physical, chemical and mineralogical evolution of the active Tolhuaca geothermal system in the Andes of southern Chile. We used temperature measurements in the deep wells and geochemical analyses of borehole fluid samples to constrain present-day fluid conditions. In addition, we reconstructed the paleo-fluid temperatures and chemistry from microthermometry and LA-ICP-MS analysis of fluid inclusions taken from well-constrained parageneses in vein samples retrieved from a 1000 m borehole core. Based on core logging, mineralogical observations and fluid inclusions data we identify four stages (S1-S4) of progressive hydrothermal alteration. An early heating event (S1) was followed by the formation of a clay-rich cap in the upper zone (< 670 m) and the development of a propylitic alteration assemblage at greater depth (S2). Boiling, flashing and brecciation occurred later (S3), followed by a final phase of fluid mixing and boiling (S4). The evolution of hydrothermal alteration at Tolhuaca has produced a mineralogical, hydrological and structural vertical segmentation of the system through the development of a low-permeability, low-cohesion clay-rich cap at shallow depth. The quantitative chemical analyses of fluid inclusions and borehole fluids reveal a significant change in chemical conditions during the evolution of Tolhuaca. Whereas borehole (present-day) fluids are rich in Au, B and As, but Cu-poor (B/Na 100.5, As/Na 10- 1.1, Cu/Na 10- 4.2), the paleofluids trapped in fluid inclusions are Cu-rich but poor in B and As (B/Na 10- 1, As/Na 10- 2.5, Cu/Na 10- 2.5 in average). We interpret the fluctuations in fluid chemistry at Tolhuaca as the result of transient supply of metal-rich, magmatically derived fluids where As, Au and Cu are geochemically decoupled. Since these fluctuating physical and chemical conditions at the reservoir produced a mineralogical vertical segmentation of the system that affects the mechanical and hydrological properties of host rock, we explored the effect of the development of a low-cohesion low-permeability clay cap on the conditions of fault rupture and on the long-term thermal structure of the system. These analyses were performed by using rock failure condition calculations and numerical simulations of heat and fluid flows. Calculations of the critical fluid pressures required to produce brittle rupture indicate that within the clay-rich cap, the creation or reactivation of highly permeable extensional fractures is inhibited. In contrast, in the deep upflow zone the less pervasive formation of clay mineral assemblages has allowed retention of rock strength and dilatant behavior during slip, sustaining high permeability conditions. Numerical simulations of heat and fluid flows support our observations and suggest that the presence of a low permeability clay cap has helped increase the duration of high-enthalpy conditions by a factor of three in the deep upflow zone at Tolhuaca geothermal system, when compared with an evolutionary scenario where a clay cap was not developed. Furthermore, our data demonstrate that the dynamic interplay between fluid flow, crack-seal processes and hydrothermal alteration are key factors in the evolution of the hydrothermal system, leading to the development of a high enthalpy reservoir at the flank of the dormant Tolhuaca volcano.

Constraints on the composition of ore fluids and implications for mineralising events at the Cleo gold deposit, Eastern Goldfields Province, Western Australia

USGS Publications Warehouse

Brown, S.M.; Johnson, C.A.; Watling, R.J.; Premo, W.R.

2003-01-01

The Cleo gold deposit, 55 km south of Laverton in the Eastern Goldfields Province of Western Australia, is characterised by banded iron-formation (BIF)-hosted ore zones in the gently dipping Sunrise Shear Zone and high-grade vein-hosted ore in the Western Lodes. There is evidence that gold mineralisation in the Western Lodes (which occurred at ca 2655 Ma) post-dates the majority of displacement along the Sunrise Shear Zone, but it remains uncertain if the ore in both structures formed simultaneously or separately. Overall, the Pb, Nd, Sr, C. O and S isotopic compositions of ore-related minerals from both the Western Lodes and ore zones in the Sunrise Shear Zone are similar. Early low-salinity aqueous-carbonic fluids and late high-salinity fluids with similar characteristics are trapped in inclusions in quartz veins from both the Sunrise Shear Zone and the Western Lodes. The early CO2, CO2-H2O, and H2O- dominant inclusions are interpreted as being related to ore formation, and to have formed from a single low-salinity aqueous-carbonic fluid as a result of intermittent fluid immiscibility. Homogenisation temperatures indicate that these inclusions were trapped at approximately 280??C and at approximately 4 km depth, in the deeper epizonal range. Differences between the ore zones are detected in the trace-element composition of gold samples, with gold from the Sunrise Shear Zone enriched in Ni, Pb, Sn, Te and Zn, and depleted In As, Bi, Cd, Cu and Sb, relative to gold from the Western Lodes. Although there are differences in gold composition between the Sunrise Shear Zone and Western Lodes, and hence the metal content of ore fluids may have varied slightly between the different ore zones, no other systematic fluid or solute differences are detected between the ore zones. Given the fact that the ore fluids in each zone have very similar bulk properties, the considerable differences in gold grade, sulfide mineral abundance, and ore textures between the two ore zones most likely result from different gold-deposition mechanisms. The association of ore zones in the Sunrise Shear Zone with pyrite-replaced BIF suggests that wall-rock sulfidation was the most significant mechanism of gold precipitation, through the destabilisation of gold-bisulfide complexes. The Western Lodes, however, do not exhibit any host-rock preference and multistage veins commonly contain coarse-grained gold. Fluid-inclusion characteristics and breccia textures in veins in the Western Lodes suggest that rapid pressure changes, brought about by intermittent release of overpressured fluids and concomitant phase separation, are likely to have caused the destabilisation of gold-thiocomplexes, leading to formation of higher-grade gold ore zones.

Pressure/temperature fluid cell apparatus for the neutron powder diffractometer instrument: Probing atomic structure in situ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hsiu-Wen; Fanelli, Victor R.; Reiche, Helmut M.

This contribution describes a new local structure compatible gas/liquid cell apparatus for probing disordered materials at high pressures and variable temperatures in the Neutron Powder Diffraction instrument at the Lujan Neutron Scattering Center, Los Alamos National Laboratory. The new sample environment offers choices for sample canister thickness and canister material type. Finite element modeling is utilized to establish maximum allowable working pressures of 414 MPa at 15 K and 121 MPa at 600 K. High quality atomic pair distribution function data extraction and modeling have been demonstrated for a calibration standard (Si powder) and for supercritical and subcritical CO{sub 2}more » measurements. The new sample environment was designed to specifically target experimental studies of the local atomic structures involved in geologic CO{sub 2} sequestration, but will be equally applicable to a wide variety of energy applications, including sorption of fluids on nano/meso-porous solids, clathrate hydrate formation, catalysis, carbon capture, and H{sub 2} and natural gas uptake/storage.« less

Pressure/temperature fluid cell apparatus for the neutron powder diffractometer instrument: Probing atomic structure in situ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hsiu -Wen; Fanelli, Victor R.; Reiche, Helmut M.

This contribution describes a new local structure compatible gas/liquid cell apparatus for probing disordered materials at high pressures and variable temperatures in the Neutron Powder Diffraction instrument at the Lujan Neutron Scattering Center, Los Alamos National Laboratory. The new sample environment offers choices for sample canister thickness and canister material type. Finite element modeling is utilized to establish maximum allowable working pressures of 414 MPa at 15 K and 121 MPa at 600 K. High quality atomic pair distribution function data extraction and modeling have been demonstrated for a calibration standard (Si powder) and for supercritical and subcritical CO 2measurements.more » As a result, the new sample environment was designed to specifically target experimental studies of the local atomic structures involved in geologic CO 2 sequestration, but will be equally applicable to a wide variety of energy applications, including sorption of fluids on nano/meso-porous solids, clathrate hydrate formation, catalysis, carbon capture, and H 2 and natural gas uptake/storage.« less

Pressure/temperature fluid cell apparatus for the neutron powder diffractometer instrument: Probing atomic structure in situ

DOE PAGES

Wang, Hsiu -Wen; Fanelli, Victor R.; Reiche, Helmut M.; ...

2014-12-24

This contribution describes a new local structure compatible gas/liquid cell apparatus for probing disordered materials at high pressures and variable temperatures in the Neutron Powder Diffraction instrument at the Lujan Neutron Scattering Center, Los Alamos National Laboratory. The new sample environment offers choices for sample canister thickness and canister material type. Finite element modeling is utilized to establish maximum allowable working pressures of 414 MPa at 15 K and 121 MPa at 600 K. High quality atomic pair distribution function data extraction and modeling have been demonstrated for a calibration standard (Si powder) and for supercritical and subcritical CO 2measurements.more » As a result, the new sample environment was designed to specifically target experimental studies of the local atomic structures involved in geologic CO 2 sequestration, but will be equally applicable to a wide variety of energy applications, including sorption of fluids on nano/meso-porous solids, clathrate hydrate formation, catalysis, carbon capture, and H 2 and natural gas uptake/storage.« less

Method of absorbance correction in a spectroscopic heating value sensor

DOEpatents

Saveliev, Alexei; Jangale, Vilas Vyankatrao; Zelepouga, Sergeui; Pratapas, John

2013-09-17

A method and apparatus for absorbance correction in a spectroscopic heating value sensor in which a reference light intensity measurement is made on a non-absorbing reference fluid, a light intensity measurement is made on a sample fluid, and a measured light absorbance of the sample fluid is determined. A corrective light intensity measurement at a non-absorbing wavelength of the sample fluid is made on the sample fluid from which an absorbance correction factor is determined. The absorbance correction factor is then applied to the measured light absorbance of the sample fluid to arrive at a true or accurate absorbance for the sample fluid.

Leaching of organic acids from macromolecular organic matter by non-supercritical CO2

NASA Astrophysics Data System (ADS)

Sauer, P.; Glombitza, C.; Kallmeyer, J.

2012-04-01

The storage of CO2 in underground reservoirs is discussed controversly in the scientific literature. The worldwide search for suitable storage formations also considers coal-bearing strata. CO2 is already injected into seams for enhanced recovery of coal bed methane. However, the effects of increased CO2 concentration, especially on organic matter rich formations, are rarely investigated. The injected CO2 will dissolve in the pore water, causing a decrease in pH and resulting in acidic formation waters. Huge amounts of low molecular weight organic acids (LMWOAs) are chemically bound to the macromolecular matrix of sedimentary organic matter and may be liberated by hydrolysis, which is enhanced by the acidic porewater. Recent investigations outlined the importance of LMWOAs as a feedstock for microbial life in the subsurface [1]. Therefore, injection of CO2 into coal formations may result in enhanced nutrient supply for subsurface microbes. To investigate the effect of high concentrations of dissolved CO2 on the release of LMWOAs from coal we developed an inexpensive high-pressure high temperature system that allows manipulating the partial pressure of dissolved gases at pressures and temperatures up to 60 MPa and 120° C, respectively. In a reservoir vessel, gases are added to saturate the extraction medium to the desired level. Inside the extraction vessel hangs a flexible and inert PVDF sleeve (polyvinylidene fluoride, almost impermeable for gases), holding the sample and separating it from the pressure fluid. The flexibility of the sleeve allows for subsampling without loss of pressure. Coal samples from the DEBITS-1 well, Waikato Basin, NZ (R0 = 0.29, TOC = 30%). were extracted at 90° C and 5 MPa, either with pure or CO2-saturated water. Subsamples were taken at different time points during the extraction. The extracted LMWOAs such as formate, acetate and oxalate were analysed by ion chromatography. Yields of LMWOAs were higher with pure water than with CO2-saturated water, revealing a suppressing effect of CO2. Both extractions had higher yields than those reported for soxhlet extraction [2]. LMWOAs found in the extraction fluid may not just result from hydrolysis but also from different secondary reactions. It was suggested that oxalate in aqueous extracts of coals is a result of the decomposition of 1,2-dihydroxy-carboxylic acids [3]. We assume that for oxalate (and maybe for other LMWOAs as well) the extraction yield is not only affected by hydrolysis but also by secondary reactions, which may be inhibited or suppressed in the presence of CO2 in the extraction medium. During soxhlet extraction the sample only gets into contact with freshly distilled water, not with an acidic fluid. This may explain the lower yields.

Fluid sampling device

NASA Technical Reports Server (NTRS)

Studenick, D. K. (Inventor)

1977-01-01

An inlet leak is described for sampling gases, more specifically, for selectively sampling multiple fluids. This fluid sampling device includes a support frame. A plurality of fluid inlet devices extend through the support frame and each of the fluid inlet devices include a longitudinal aperture. An opening device that is responsive to a control signal selectively opens the aperture to allow fluid passage. A closing device that is responsive to another control signal selectively closes the aperture for terminating further fluid flow.

Genetic characteristics of fluid inclusions in sphalerite from the Silesian-Cracow ores, Poland

USGS Publications Warehouse

Kozlowski, A.; Leach, D.L.; Viets, J.G.

1996-01-01

Fluid inclusion studies in sphalerite from early-stage Zn-Pb mineralization in the Silesian-Cracow region (southern Poland), yielded homogenization temperatures (Th) from 80 to 158??C. Vertical thermal gradient of the parent fluids was 6 to 10??C, and the ore crystallization temperature ranges varied from <10??C at deep levels to 25??C at shallow levels. The peculiarities of formation of primary and secondary fluid inclusions from organic-matter-bearing water-dominated medium, position of the inclusions in crystals, features of secondary inclusions, the inclusion refilling phenomena, their formation on recrystallization of ores, and Th distribution in single fissure fillings were considered. The ore-forming fluids were liquid-hydrocarbon-bearing aqueous solutions of Na-Ca-Cl type with lower Ca contents in the south and higher Ca contents in the north of the region. The ore-forming fluids had salinities from nul to about 23 weight percent of NaCl equivalent. Three types of fluids were recognized, that mixed during ore precipitation: a) ascending fluids of low-to-moderate salinity and high, b) formation brines of high salinity and moderate Th, and c) descending waters of low salinity and low-to-moderate Th.

High-resolution chemical composition of geothermal scalings from Hungary: Preliminary results

NASA Astrophysics Data System (ADS)

Boch, Ronny; Dietzel, Martin; Deák, József; Leis, Albrecht; Mindszenty, Andrea; Demeny, Attila

2015-04-01

Geothermal fluids originating from several hundreds to thousands meters depth mostly hold a high potential for secondary mineral precipitation (scaling) due to high total dissolved solid contents at elevated temperature and pressure conditions. The precipitation of e.g. carbonates, sulfates, sulfides, and silica has shown to cause severe problems in geothermal heat and electric power production, when clogging of drill-holes, downhole pumps, pipes and heat exchangers occurs (e.g. deep geothermal doublet systems). Ongoing scaling reduces the efficiency in energy extraction and might even question the abandonment of installations in worst cases. In an attempt to study scaling processes both temporally and spatially we collected mineral precipitates from selected sites in Hungary (Bükfürdo, Szechenyi, Szentes, Igal, Hajduszoboszlo). The samples of up to 8 cm thickness were recovered from different positions of the geothermal systems and precipitated from waters of various temperatures (40-120 °C) and variable overall chemical composition. Most of these scalings show fine lamination patterns representing mineral deposition from weeks up to 45 years at our study sites. Solid-fluid interaction over time captured in the samples are investigated applying high-resolution analytical techniques such as laser-ablation mass-spectrometry and electron microprobe, micromill-sampling for stable isotope analysis, and micro-XRD combined with hydrogeochemical modeling. A detailed investigation of the processes determining the formation and growth of precipitates can help to elucidate the short-term versus long-term geothermal performance with regard to anthropogenic and natural reservoir and production dynamics. Changes in fluid chemistry, temperature, pressure, pH, degassing rate (CO2) and flow rate are reflected by the mineralogical, chemical and isotopic composition of the precipitates. Consequently, this high-resolution approach is intended as a contribution to decipher the environmental conditions during the formation of the investigated scalings and to increase our knowledge on retarding and preventive measures of scaling for geothermal applications.

By-products of the serpentinization process on the Oman ophiolite : chemical and isotopic composition of carbonate deposits in alkaline springs, and associated secondary phases

NASA Astrophysics Data System (ADS)

Sissmann, O.; Martinez, I.; Deville, E.; Beaumont, V.; Pillot, D.; Prinzhofer, A.; Vacquand, C.; Chaduteau, C.; Agrinier, P.; Guyot, F. J.

2014-12-01

The isotopic compositions (d13C, d18O) of natural carbonates produced by the alteration of basic and ultrabasic rocks on the Oman ophiolite have been measured in order to better understand their formation mechanisms. Fossil carbonates developed on altered peridotitic samples, mostly found in fractures, and contemporary carbonates were studied. The samples bear a large range of d13C. Those collected in veins are magnesian (magnesite, dolomite) and have a carbon signature reflecting mixing of processes and important fractionation (-11‰ to 8‰). Their association with talc and lizardite suggests they are by-products of a serpentinization process, that must have occurred as a carbon-rich fluid was circulating at depth. On the other hand, the carbonates are mostly calcic when formed in alkaline springs, most of which are located in the vicinity of lithological discontinuities such as the peridotite-gabbro contact (Moho). Aragonite forms a few meters below the surface of the ponds in Mg-poor water, and is systematically associated with brucite (Mg(OH)2). This suggests most of the Mg dissolved at depth has reprecipitated during the fluid's ascension through fractures or faults as carbonates and serpentine. Further up, on the surface waters of the ponds (depleted in Mg and D.I.C.), thin calcite films precipitate and reach extremely negative d13C values (-28‰), which could reflect either a biological carbon source, or kinetic fractionation from pumping atmospheric CO2. Their formation represent an efficient and natural process for carbon dioxide mineral sequestration. The d18O signature from all samples confirm the minerals crystallized from a low-temperature fluid. The hyperalkaline conditions (pH between 11 and 12) allowing for these fast precipitation kinetics are generated by the serpentinization process occurring at depth, as indicated by the measured associated H2-rich gas flows (over 50%) seeping out to the surface.

Quantification of CO2-FLUID-ROCK Reactions Using Reactive and Non-Reactive Tracers

NASA Astrophysics Data System (ADS)

Matter, J.; Stute, M.; Hall, J. L.; Mesfin, K. G.; Gislason, S. R.; Oelkers, E. H.; Sigfússon, B.; Gunnarsson, I.; Aradottir, E. S.; Alfredsson, H. A.; Gunnlaugsson, E.; Broecker, W. S.

2013-12-01

Carbon dioxide mineralization via fluid-rock reactions provides the most effective and long-term storage option for geologic carbon storage. Injection of CO2 in geologic formations induces CO2 -fluid-rock reactions that may enhance or decrease the storage permanence and thus the long-term safety of geologic carbon storage. Hence, quantitative characterization of critical CO2 -fluid-rock interactions is essential to assess the storage efficiency and safety of geologic carbon storage. In an attempt to quantify in-situ fluid-rock reactions and CO2 transport relevant for geologic carbon storage, we are testing reactive (14C, 13C) and non-reactive (sodium fluorescein, amidorhodamine G, SF5CF3, and SF6) tracers in an ongoing CO2 injection in a basaltic storage reservoir at the CARBFIX pilot injection site in Iceland. At the injection site, CO2 is dissolved in groundwater and injected into a permeable basalt formation located 500-800 m below the surface [1]. The injected CO2 is labeled with 14C by dynamically adding calibrated amounts of H14CO3-solution into the injection stream in addition to the non-reactive tracers. Chemical and isotopic analyses of fluid samples collected in a monitoring well, reveal fast fluid-rock reactions. Maximum SF6 concentration in the monitoring well indicates the bulk arrival of the injected CO2 solution but dissolved inorganic carbon (DIC) concentration and pH values close to background, and a potentially lower 14C to SF6 ratio than the injection ratio suggest that most of the injected CO2 has reacted with the basaltic rocks. This is supported by δ13CDIC, which shows a drop from values close to the δ 13C of the injected CO2 gas (-3‰ VPDB) during breakthrough of the CO2 plume to subsequent more depleted values (-11.25‰ VPDB), indicating precipitation of carbonate minerals. Preliminary mass balance calculations using mixing relationships between the background water in the storage formation and the injected solution, suggest that approximately 85% of the injected CO2 must have reacted along the flow path from the injection well to the monitoring well within less than one year. Monitoring is still going on and we will extend the time series and the mass balance accordingly. Our study demonstrates that by combining reactive and non-reactive tracers, we are able to quantify CO2-fluid-rock interactions on a reservoir scale. [1] Gislason et al. (2010), Int. J. Greenh. Gas Con. 4, 537-545.

Hydraulic properties of siliciclastic geothermal reservoir rocks under triaxial stress conditions, a multidisciplinary approach.

NASA Astrophysics Data System (ADS)

Bakker, Richard; Gholizadeh Doonechaly, Nima; Bruhn, David

2017-04-01

Cretaceous Sandstone bodies in the subsurface of western Netherlands are already used for heating some of the greenhouses in that area. The reservoirs used are typically at depths between 1500 and 3000m, with temperatures generally <100 ˚C. For higher temperature applications deeper reservoirs are required. However, deeper reservoirs are subjected to higher effective pressures due to more overburden, which can lead to more compacted rocks, and thereby reduced permeability. We assess the effects of effective pressure on Triassic Buntsandstein, a formation targeted to act as a deep geothermal reservoir in the western Netherlands. Rock samples are acquired from laterally equivalent quarries and prepared for permeability measurements within a tri-axial apparatus. To determine anisotropy, cores are drilled both perpendicular and parallel to bedding. Experiments are conducted by maintaining hydrostatic confining pressure, stepwise increasing up to 700 bar (if still permeable enough for accurate measurements) and a pore pressure of 25 bar. At each step the permeability is assessed by imposing a number of constant flow rates and continuous measurement of the pore pressure difference between up and downstream reservoirs. Throughout the experiment the sample strain is measured in radial and axial directions, such that elastic constants can be determined and micromechanical mechanisms may be observed. In addition to measurements on in-tact rock samples, we also assess the effect of induced fracturing on permeability by similar measurements. First, rock samples are fractured within the tri-axial cell with normal jacketing to evaluate the stress conditions of failure. Secondly, the experiment is repeated using relatively strong jackets which remain sealing after sample failure, allowing for permeability measurements. Preliminary results show that an increase of confining pressure leads to a decrease of permeability by three orders of magnitude, from 1e-13 to 1e-16 m2. Anisotropy results in permeability parallel to bedding to be roughly one order of magnitude higher than perpendicular to it. Based on the collected data, the validity of the available exponential permeability-porosity-stress relationship is assessed and the model parameters with the best fitting characteristic is chosen for the selected formation. The established relationship is then used as an input for field scale numerical simulation of cold fluid circulation in Buntsandstein formation to predict the reservoir behavior over longer term of fluid circulation. The Finite Element Method is used to evaluate the reservoir behaviour during injection/production of the cold/hot fluid in a fully coupled poro-thermo-elastic environment. Weighted residual method is used for deriving the weak formulation of the mass-, momentum- and energy balance equations. Consequently the standard Galerkin approach is used for spatial discretization of the weak formulas. Temporal discretization is also carried out in a fully implicit manner to avoid the time-stepping limitation. The preliminary results of this study show a promising capacity of heat extraction from the Buntsandstein formation as a geothermal reservoir within western Netherlands.

Mapping bone interstitial fluid movement: Displacement of ferritin tracer during histological processing

PubMed Central

Ciani, Cesare; Doty, Stephen B.; Fritton, Susannah P.

2014-01-01

Bone interstitial fluid flow is thought to play a fundamental role in the mechanical stimulation of bone cells, either via shear stresses or cytoskeletal deformations. Recent evidence indicates that osteocytes are surrounded by a fiber matrix that may be involved in the mechanotransduction of external stimuli as well as in nutrient exchange. In our previous tracer studies designed to map how different-sized molecules travel through the bone porosities, we found that injected ferritin was confined to blood vessels and did not pass into the mineralized matrix. However, other investigators have shown that ferritin forms halo-shaped labeling that enters the mineralized matrix around blood vessels. This labeling is widely used to explain normal interstitial fluid movement in bone; in particular, it is said to demonstrate bulk centrifugal interstitial fluid movement away from a highly pressurized vascular porosity. In addition, appositional ferritin fronts are said to demonstrate centrifugal interstitial fluid movement from the medullary canal to the periosteal surface. The purpose of this study was to investigate the conflicting ferritin labeling results by evaluating the role of different histological processes in the formation of ferritin “halos.” Ferritin was injected into the rat vasculature and allowed to circulate for 5 min. Samples obtained from tibiae were reacted for different times with Perl's reagent and then were either paraffin-embedded or sectioned with a cryostat. Halo-like labeling surrounding vascular pores was found in all groups, ranging from 1.2–3.9% for the samples treated with the shortest histological processes (unembedded, frozen sections) to 5.6–15% for the samples treated with the longest histological processes (paraffin-embedded sections). These results indicate that different histological processing methods are able to create ferritin “halos,” with some processing methods allowing more redistribution of the ferritin tracer than others. Based on these results and the fact that “halo” labeling has not been found with any other tracer, as we seek to further delineate the movement of interstitial fluid and the role it plays in bone mechanotransduction, we believe that ferritin “halo” labeling should not be used to demonstrate physiological bone interstitial fluid flow. PMID:15964255

Mapping bone interstitial fluid movement: displacement of ferritin tracer during histological processing.

PubMed

Ciani, Cesare; Doty, Stephen B; Fritton, Susannah P

2005-09-01

Bone interstitial fluid flow is thought to play a fundamental role in the mechanical stimulation of bone cells, either via shear stresses or cytoskeletal deformations. Recent evidence indicates that osteocytes are surrounded by a fiber matrix that may be involved in the mechanotransduction of external stimuli as well as in nutrient exchange. In our previous tracer studies designed to map how different-sized molecules travel through the bone porosities, we found that injected ferritin was confined to blood vessels and did not pass into the mineralized matrix. However, other investigators have shown that ferritin forms halo-shaped labeling that enters the mineralized matrix around blood vessels. This labeling is widely used to explain normal interstitial fluid movement in bone; in particular, it is said to demonstrate bulk centrifugal interstitial fluid movement away from a highly pressurized vascular porosity. In addition, appositional ferritin fronts are said to demonstrate centrifugal interstitial fluid movement from the medullary canal to the periosteal surface. The purpose of this study was to investigate the conflicting ferritin labeling results by evaluating the role of different histological processes in the formation of ferritin "halos." Ferritin was injected into the rat vasculature and allowed to circulate for 5 min. Samples obtained from tibiae were reacted for different times with Perl's reagent and then were either paraffin-embedded or sectioned with a cryostat. Halo-like labeling surrounding vascular pores was found in all groups, ranging from 1.2-3.9% for the samples treated with the shortest histological processes (unembedded, frozen sections) to 5.6-15% for the samples treated with the longest histological processes (paraffin-embedded sections). These results indicate that different histological processing methods are able to create ferritin "halos," with some processing methods allowing more redistribution of the ferritin tracer than others. Based on these results and the fact that "halo" labeling has not been found with any other tracer, as we seek to further delineate the movement of interstitial fluid and the role it plays in bone mechanotransduction, we believe that ferritin "halo" labeling should not be used to demonstrate physiological bone interstitial fluid flow.

Determining the Area of Review for Industrial Waste Disposal Wells.

DTIC Science & Technology

1981-12-01

pressure increases sufficiently to force formation fluids and/or injected wastes up abandoned well bores to contaminate underground sources of drinking...Drilling Mud Circulating System . . 72 9. Increase in Gel Strength of Various Mud Types With Time . . . . . . . . . . . . . . . . . . 96 10. Gel... increased fluid pressure in a disposal zone which results from a waste injection operation may force injected and/or formation fluid to migrate up an

Rebound and jet formation of a fluid-filled sphere

NASA Astrophysics Data System (ADS)

Killian, Taylor W.; Klaus, Robert A.; Truscott, Tadd T.

2012-12-01

This study investigates the impact dynamics of hollow elastic spheres partially filled with fluid. Unlike an empty sphere, the internal fluid mitigates some of the rebound through an impulse driven exchange of energy wherein the fluid forms a jet inside the sphere. Surprisingly, this occurs on the second rebound or when the free surface is initially perturbed. Images gathered through experimentation show that the fluid reacts more quickly to the impact than the sphere, which decouples the two masses (fluid and sphere), imparts energy to the fluid, and removes rebound energy from the sphere. The experimental results are analyzed in terms of acceleration, momentum and an energy method suggesting an optimal fill volume in the neighborhood of 30%. While the characteristics of the fluid (i.e., density, viscosity, etc.) affect the fluid motion (i.e., type and size of jet formation), the rebound characteristics remain similar for a given fluid volume independent of fluid type. Implications of this work are a potential use of similar passive damping systems in sports technology and marine engineering.

Deciphering fluid sources of hydrothermal systems: A combined Sr- and S-isotope study on barite (Schwarzwald, SW Germany)

USGS Publications Warehouse

Staude, S.; Gob, S.; Pfaff, K.; Strobele, F.; Premo, W.R.; Markl, G.

2011-01-01

Primary and secondary barites from hydrothermal mineralizations in SW Germany were investigated, for the first time, by a combination of strontium (Sr) isotope systematics (87Sr/86Sr), Sr contents and δ34S values to distinguish fluid sources and precipitation mechanisms responsible for their formation. Barite of Permian age derived its Sr solely from crystalline basement rocks, whereas all younger barite also incorporate Sr from formation waters of the overlying sediments. In fact, most of the Sr in younger barite is leached from Lower and Middle Triassic sediments. In contrast, most of the sulfur (S) of Permian, Jurassic and northern Schwarzwald Miocene barite originated from basement rocks. The S source of Upper Rhinegraben (URG)-related Paleogene barite differs depending on geographic position: for veins of the southern URG, it is the Oligocene evaporitic sequence, while central URG mineralizations derived its S from Middle Triassic evaporites. Using Sr isotopes of barite of known age combined with estimates on the Sr contents and Sr isotopic ratios of the fluids' source rocks, we were able to quantify mixing ratios of basement-derived fluids and sedimentary formation waters for the first time. These calculations show that Jurassic barite formed by mixing of 75–95% ascending basement-derived fluids with 5–25% sedimentary formation water, but that only 20–55% of the Sr was brought by the basement-derived fluid to the depositional site. Miocene barite formed by mixing of an ascending basement-derived brine (60–70%) with 30–40% sedimentary formation waters. In this case, only 8–15% of the Sr was derived from the deep brine. This fluid-mixing calculation is an example for deposits in which the fluid source is known. This method applied to a greater number of deposits formed at different times and in various geological settings may shed light on more general causes of fluid movement in the Earth's crust and on the formation of hydrothermal ore deposits.

Hydroxyl Radical Formation from HULIS and Fe(II) Interactions: Fulvic Acid-Fe(II) Complexes in Simulated and Human Lung Fluids

NASA Astrophysics Data System (ADS)

Gonzalez, D.

2017-12-01

Inhalation of fine particulate matter (PM2.5) has long been associated with adverse health outcomes. However, the causative agents and underlying mechanisms for these health effects have yet to be identified. One hypothesis is that PM2.5 deposited in the alveoli produce an excess of highly reactive radicals, leading to oxidative stress. The OH radical may be the most physiologically damaging, capable of oxidizing of lipids, proteins and DNA. Due to the variability and uncertainty in PM2.5 composition, the components that contribute to OH formation are not well understood. Soluble Fe is a component of PM2.5that produces OH under physiological conditions. Humic-like substances are water soluble organics found in biomass burning and tobacco smoke. Humic-like substances are capable of binding to Fe and enhancing OH formation, but this chemistry is not well understood. In this work, we use soil derived fulvic acid as a surrogate for Humic-like substances and investigate its effect on OH formation from Fe(II) under conditions relevant to the lungs. We use a fluorescent OH trapping probe, chemical kinetics and thermodynamic modeling to investigate OH formation from fulvic acid and Fe(II) dissolved in simulated and human lung fluids. In simulated lung fluid, we find that fulvic acid binds to Fe(II) and enhances the rate of key reactions that form OH. When fulvic acid is added to human lung fluids containing Fe(II), an enhancement of OH formation is observed. In human lung fluid, fulvic acid and metal binding proteins compete for Fe binding. These metal binding proteins are typically not found in simulated lung fluids. Results show that fulvic acid strongly binds Fe(II) and catalyzes key reactions that form OH in both simulated and human lung fluids. These results may help explain the role of Humic-like substances and Fe in oxidative stress and adverse health outcomes. Furthermore, we suggest that future studies employ simulated lung fluids containing metal binding proteins to better reflect human lung fluids.

The Microgravity Research Experiments (MICREX) Data Base. Volume 2

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the experimental facilities employed to examine reduced gravity fluid flow, (3) discusses the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

The Microgravity Research Experiments (MICREX) Data Base. Volume 1

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J.C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators, (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the experimental facilities employed to examine reduced gravity fluid flow, (3) discusses the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

Streptococcus mutans dextransucrase: stimulation by phospholipids from human sera and oral fluids.

PubMed Central

Schachtele, C F; Harlander, S K; Bracke, J W; Ostrum, L C; Maltais, J A; Billings, R J

1978-01-01

Serum, gingival crevicular fluid, and parotid, submandibular, and labial minor gland saliva from four individuals stimulated glucan formation from sucrose by the Streptococcus mutans strain 6715 dextransucrase (EC 2.4.1.5). At final dilutions of 1:10 all of the fluids stimulated crude enzyme preparations approximately 1.8-fold. The fluids stimulated the purified water-insoluble glucan-synthesizing form of the dextransucrase approximately 3.2-fold and the water-soluble glucan-producing form of the enzyme approximately 2.4-fold. The fluids all contained concentrations of stimulatory material that could be reduced to undetectable levels only after dilutions of greater than 1:1,000. The increased rates of glucan formation caused by the fluids and dextran were additive, indicating that stimulation by the fluids was primarily due to interactions with entities other than glucan primer molecules. In contrast, the elevated levels of glucan formation in the presence of the fluids was not further enhanced by the addition of lysophosphatidylcholine. Lysophosphatidylcholine purified from parotid and submandibular saliva by solvent extraction and thin-layer chromatography stimulated the dextransucrase as effectively as egg yolk lysophosphatidylcholine. Thus, phospholipids normally found in human oral fluids can enhance the activity of an enzyme believed to be directly associated with the cariogenic potential of S. mutans. PMID:365766

Diamond formation due to a pH drop during fluid–rock interactions

DOE PAGES

Sverjensky, Dimitri A.; Huang, Fang

2015-11-03

Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly withmore » eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.« less

Diamond formation due to a pH drop during fluid–rock interactions

PubMed Central

Sverjensky, Dimitri A.; Huang, Fang

2015-01-01

Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly with eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state. PMID:26529259

The effect of spherical nanoparticles on rheological properties of bi-dispersed magnetorheological fluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kannappan, K. Thiruppathi, E-mail: thiruppathi.ka@gmail.com; Laherisheth, Zarana; Parekh, Kinnari

2015-06-24

In the present investigation, the rheological properties of bi-dispersed magnetorheological (MR) fluid based on Fe{sub 3}O{sub 4} nanosphere and microsphere of iron particles are experimentally investigated. The MR fluid is prepared by substituting nanosphere of 40nm Fe{sub 3}O{sub 4} particles in MR fluids having microsphere iron particles (7-8 μm). Three different weight fractions (0%, 1% and 3%) of nanosphere-microsphere MR fluids are synthesized. In the absence of the magnetic field, substitution of magnetic nanosphere decreases the viscosity lower than without substituted sample at high as well as low shear rate. Upon the application of the magnetic field, the particles alignmore » along the direction of the field, which promotes the yield stress. Here too the yield stress value decreases with magnetic nanosphere substitution. This behaviour is explain based on the inter-particle interaction as well as formation of nanosphere cloud around the magnetic microsphere, which effectively reduces the viscosity and works as weak point when chains are formed. Variation of dynamic yield stress with magnetic field is explained using microscopic model. In any event such fluid does not sediment and is not abrasive so it could be useful if not too high yield stress is needed.« less

Aerated drilling cutting transport analysis in geothermal well

NASA Astrophysics Data System (ADS)

Wakhyudin, Aris; Setiawan, Deni; Dwi Marjuan, Oscar

2017-12-01

Aeratad drilling widely used for geothermal drilling especially when drilled into predicted production zone. Aerated drilling give better performance on preventing lost circulation problem, improving rate of penetration, and avoiding drilling fluid invasion to productive zone. While well is drilled, cutting is produced and should be carried to surface by drilling fluid. Hole problem, especially pipe sticking will occur while the cutting is not lifted properly to surface. The problem will effect on drilling schedule; non-productive time finally result more cost to be spent. Geothermal formation has different characteristic comparing oil and gas formation. Geothermal mainly has igneous rock while oil and gas mostly sedimentary rock. In same depth, formation pressure in geothermal well commonly lower than oil and gas well while formation temperature geothermal well is higher. While aerated drilling is applied in geothermal well, Igneous rock density has higher density than sedimentary rock and aerated drilling fluid is lighter than water based mud hence minimum velocity requirement to transport cutting is larger than in oil/gas well drilling. Temperature and pressure also has impact on drilling fluid (aerated) density. High temperature in geothermal well decrease drilling fluid density hence the effect of pressure and temperature also considered. In this paper, Aerated drilling cutting transport performance on geothermal well will be analysed due to different rock and drilling fluid density. Additionally, temperature and pressure effect on drilling fluid density also presented to merge.

Real Time Mud Gas Logging During Drilling of DFDP-2B

NASA Astrophysics Data System (ADS)

Mathewson, L. A.; Toy, V.; Menzies, C. D.; Zimmer, M.; Erzinger, J.; Niedermann, S.; Cox, S.

2015-12-01

The Deep Fault Drilling Project (DFDP) aims to improve our understanding of the Alpine Fault Zone, a tectonically active mature fault system in New Zealand known to rupture in large events, by deep scientific drilling. The borehole DFDP-2B approached the Alpine Fault at depth, reaching a final depth of 892 m (820 m true vertical depth). Online gas analysis (OLGA) while drilling tracked changes in the composition of gases extracted from the circulating drill mud. The composition of fluids from fault zones can provide information about their origins, flow rates and -paths, fluid-rock interactions along these paths, and the permeability structure of the faulted rock mass. Apart from an atmospheric input, the gases in drilling mud derive from the pore space of rock, crushed at the drill bit, and from permeable layers intersected by the borehole. The rapid formation of mud wall cake seals the borehole from further fluid inflow, hence formation-derived gases enter mostly at the depth of the drill bit. OLGA analyses N2, O2, Ar, CO2, CH4, He, and H2 on a mass spectrometer, hydrocarbons CH4, C2H6, C3H8, i-C4H10, and n-C4H10 on a gas chromatograph, and Rn using a lucas-cell detector. Gas was sampled for offline analyses on noble gas and stable isotopes to complement the OLGA dataset. The principle formation-derived gases found in drilling mud during drilling of DFDP-2 were CO2 and CH4, with smaller component of H2 and He2. High radon activity is interpreted to reflect intervals of active fluid flow through highly fractured and faulted rock. 3He/4He values in many samples were extremely air-contaminated, i.e. there was almost no excess of non-atmospheric He. The 3He/4He values measured at 236 m and 610 m, which are the only analyses with uncertainties <100%, are very similar to those measured in hot springs along the Alpine Fault, e.g. Fox River (0.64 Ra), Copland (0.42 Ra), Lower Wanganui (0.81 Ra). We will compare these data to those gathered using OLGA and discuss the implications.

Patterns of pulmonary maturation in normal and abnormal pregnancy.

PubMed

Goldkrand, J W; Slattery, D S

1979-03-01

Fetal pulmonary maturation may be a variable event depending on various feto-maternal environmental and biochemical influences. The patterns of maturation were studied in 211 amniotic fluid samples from 123 patients (normal 55; diabetes 23; Rh sensitization 19; preeclampsia 26). The phenomenon of globule formation from the amniotic fluid lipid extract and is relation to pulmonary maturity was utilized for this analysis. Validation of this technique is presented. A normal curve was constructed from 22 to 42 weeks; gestation and compared to the abnormal pregnancies. Patients with class A, B, and C diabetes and Rh-sensitized pregnancies had delayed pulmonary maturation. Patients with class D diabetes and preclampsia paralleled the normal course of maturation. A discussion of these results and their possible cause is presented.

Integration of inorganic and isotopic geochemistry with endocrine disruption activity assays to assess risks to water resources near unconventional oil and gas development in Garfield County, CO.

NASA Astrophysics Data System (ADS)

Harkness, J.; Kassotis, C.; Cornelius, J.; Nagel, S.; Vengosh, A.

2016-12-01

The rise of hydraulic fracturing in the United States has sparked a debate about the impact of oil and gas development on the quality of water resources. Wastewater associated with hydraulic fracturing includes injection fluid that is a mixture of sand, freshwater and synthetic organic chemicals, flowback water that is a mixture of injection fluid and formation brine, and produced water that is primarily brine. The fluids range in salinity and chemical composition that can have different environmental impacts. We analyzed the inorganic and isotope geochemistry of 58 surface and groundwater samples near and away from unconventional oil and gas operations (UOG), along with hormonal profiles via bioassays. Cl (0.12 to 198 mg/L), Na (1.2 to 518 mg/L) and Sr (1.4 to 2410 ug/L) were higher in both groundwater and surface water near UOG wells. Four surface waters and one groundwater had Br/Cl indicative of brine contamination (>1.5x10-3). Three of the SW samples also had 87Sr/86Sr ratios similar to values found in produced or flowback water (0.7118 and 0.7158, respectively) from the Williams-Fork formation and elevated compared to background ratios (0.71062 to 0.7115). Increased progestogenic activity was observed in groundwater near UOG operations and inncreased estrogenic, androgenic, progestogenic, anti-androgenic, anti-progestogenic, and anti-glucocorticoid activities in surface water near UOG operations. The association of increased EDCs with inorganic and isotopic indicators of UOG wastewater provides evidence for possible environmental and health impacts from drilling activity.

Significant enhancement of 11-Hydroxy-THC detection by formation of picolinic acid esters and application of liquid chromatography/multi stage mass spectrometry (LC-MS(3) ): Application to hair and oral fluid analysis.

PubMed

Thieme, Detlef; Sachs, Ulf; Sachs, Hans; Moore, Christine

2015-07-01

Formation of picolinic acid esters of hydroxylated drugs or their biotransformation products is a promising tool to improve their mass spectrometric ionization efficiency, alter their fragmentation behaviour and enhance sensitivity and specificity of their detection. The procedure was optimized and tested for the detection of cannabinoids, which proved to be most challenging when dealing with alternative specimens, for example hair and oral fluid. In particular, the detection of the THC metabolites hydroxyl-THC and carboxy-THC requires ultimate sensitivity because of their poor incorporation into hair or saliva. Both biotransformation products are widely accepted as incorporation markers to distinguish drug consumption from passive contamination. The derivatization procedure was carried out by adding a mixture of picolinic acid, 4-(dimethylamino)pyridine and 2-methyl-6-nitrobenzoic anhydride in tetrahydrofuran/triethylamine to the dry extraction residues. Resulting derivatives were found to be very stable and could be reconstituted in aqueous or organic buffers and subsequently analyzed by liquid chromatography-mass spectrometry (LC-MS). Owing to the complex consecutive fragmentation patterns, the application of multistage MS3 proved to be extremely useful for a sensitive identification of doubly picolinated hydroxy-THC in complex matrices. The detection limits - estimated by comparison of corresponding signal-to-noise ratios - increased by a factor of 100 following picolination. All other species examined, like cannabinol, THC, cannabidiol, and carboxy-THC, could also be derivatized exhibiting only moderate sensitivity improvements. The assay was systematically tested using hair samples and exemplarily applied to oral fluid. Concentrations of OH-THC identified in THC-positive hair samples ranged from 0.02 to 0.29pg/mg. Copyright © 2014 John Wiley & Sons, Ltd.

Low temperature barriers with heat interceptor wells for in situ processes

DOEpatents

McKinzie, II, Billy John

2008-10-14

A system for reducing heat load applied to a frozen barrier by a heated formation is described. The system includes heat interceptor wells positioned between the heated formation and the frozen barrier. Fluid is positioned in the heat interceptor wells. Heat transfers from the formation to the fluid to reduce the heat load applied to the frozen barrier.

Apparatus for suppressing formation of vortices in the coolant fluid of a nuclear reactor and associated method

DOEpatents

Ekeroth, D.E.; Garner, D.C.; Hopkins, R.J.; Land, J.T.

1993-11-30

An apparatus and method are provided for suppressing the formation of vortices in circulating coolant fluid of a nuclear reactor. A vortex-suppressing plate having a plurality of openings therein is suspended within the lower plenum of a reactor vessel below and generally parallel to the main core support of the reactor. The plate is positioned so as to intersect vortices which may form in the circulating reactor coolant fluid. The intersection of the plate with such vortices disrupts the rotational flow pattern of the vortices, thereby disrupting the formation thereof. 3 figures.

High temperature methods for forming oxidizer fuel

DOEpatents

Bravo, Jose Luis [Houston, TX

2011-01-11

A method of treating a formation fluid includes providing formation fluid from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes carbon dioxide, hydrogen sulfide, hydrocarbons, hydrogen or mixtures thereof. Molecular oxygen is separated from air to form a molecular oxygen stream comprising molecular oxygen. The first gas stream is combined with the molecular oxygen stream to form a combined stream comprising molecular oxygen and the first gas stream. The combined stream is provided to one or more downhole burners.

Apparatus for suppressing formation of vortices in the coolant fluid of a nuclear reactor and associated method

DOEpatents

Ekeroth, Douglas E.; Garner, Daniel C.; Hopkins, Ronald J.; Land, John T.

1993-01-01

An apparatus and method are provided for suppressing the formation of vortices in circulating coolant fluid of a nuclear reactor. A vortex-suppressing plate having a plurality of openings therein is suspended within the lower plenum of a reactor vessel below and generally parallel to the main core support of the reactor. The plate is positioned so as to intersect vortices which may form in the circulating reactor coolant fluid. The intersection of the plate with such vortices disrupts the rotational flow pattern of the vortices, thereby disrupting the formation thereof.

Sampling device for withdrawing a representative sample from single and multi-phase flows

DOEpatents

Apley, Walter J.; Cliff, William C.; Creer, James M.

1984-01-01

A fluid stream sampling device has been developed for the purpose of obtaining a representative sample from a single or multi-phase fluid flow. This objective is carried out by means of a probe which may be inserted into the fluid stream. Individual samples are withdrawn from the fluid flow by sampling ports with particular spacings, and the sampling parts are coupled to various analytical systems for characterization of the physical, thermal, and chemical properties of the fluid flow as a whole and also individually.

Simultaneous Neutron and X-ray Tomography for Quantitative analysis of Geological Samples

NASA Astrophysics Data System (ADS)

LaManna, J.; Hussey, D. S.; Baltic, E.; Jacobson, D. L.

2016-12-01

Multiphase flow is a critical area of research for shale gas, oil recovery, underground CO2 sequestration, geothermal power, and aquifer management. It is critical to understand the porous structure of the geological formations in addition to the fluid/pore and fluid/fluid interactions. Difficulties for analyzing flow characteristics of rock cores are in obtaining 3D distribution information on the fluid flow and maintaining the cores in a state for other analysis methods. Two powerful non-destructive methods for obtaining 3D structural and compositional information are X-ray and neutron tomography. X-ray tomography produces information on density and structure while neutrons excel at acquiring the liquid phase and produces compositional information. These two methods can offer strong complementary information but are typically conducted at separate times and often at different facilities. This poses issues for obtaining dynamic and stochastic information as the sample will change between analysis modes. To address this, NIST has developed a system that allows for multimodal, simultaneous tomography using thermal neutrons and X-rays by placing a 90 keVp micro-focus X-ray tube 90° to the neutron beam. High pressure core holders that simulate underground conditions have been developed to facilitate simultaneous tomography. These cells allow for the control of confining pressure, axial load, temperature, and fluid flow through the core. This talk will give an overview the simultaneous neutron and x-ray tomography capabilities at NIST, the benefits of multimodal imaging, environmental equipment for geology studies, and several case studies that have been conducted at NIST.

Experimental evidence for chemo-mechanical coupling during carbon mineralization in ultramafic rocks

NASA Astrophysics Data System (ADS)

Lisabeth, H. P.; Zhu, W.; Kelemen, P. B.; Ilgen, A.

2017-09-01

Storing carbon dioxide in the subsurface as carbonate minerals has the benefit of long-term stability and immobility. Ultramafic rock formations have been suggested as a potential reservoir for this type of storage due to the availability of cations to react with dissolved carbon dioxide and the fast reaction rates associated with minerals common in ultramafic formations; however, the rapid reactions have the potential to couple with the mechanical and hydraulic behavior of the rocks and little is known about the extent and mechanisms of this coupling. In this study, we argue that the dissolution of primary minerals and the precipitation of secondary minerals along pre-existing fractures in samples lead to reductions in both the apparent Young's modulus and shear strength of aggregates, accompanied by reduction in permeability. Hydrostatic and triaxial deformation experiments were run on dunite samples saturated with de-ionized water and carbon dioxide-rich solutions while stress, strain, permeability and pore fluid chemistry were monitored. Sample microstructures were examined after reaction and deformation using scanning electron microscopy (SEM). The results show that channelized dissolution and carbonate mineral precipitation in the samples saturated with carbon dioxide-rich solutions modify the structure of grain boundaries, leading to the observed reductions in stiffness, strength and permeability. A geochemical model was run to help interpret fluid chemical data, and we find that the apparent reaction rates in our experiments are faster than rates calculated from powder reactors, suggesting mechanically enhanced reaction rates. In conclusion, we find that chemo-mechanical coupling during carbon mineralization in dunites leads to substantial modification of mechanical and hydraulic behavior that needs to be accounted for in future modeling efforts of in situ carbon mineralization projects.

Gas-water-rock interactions in Frio Formation following CO2 injection: Implications for the storage of greenhouse gases in sedimentary basins

USGS Publications Warehouse

Kharaka, Yousif K.; Cole, David R.; Hovorka, Susan D.; Gunter, W.D.; Knauss, Kevin G.; Freifeild, Barry M.

2006-01-01

To investigate the potential for the geologic storage of CO2 in saline sedimentary aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick sandstone section of the Frio Formation, a regional brine and oil reservoir in the U.S. Gulf Coast. Fluid samples obtained from the injection and observation wells before CO2 injection showed a Na-Ca-Cl–type brine with 93,000 mg/L total dissolved solids (TDS) at near saturation with CH4 at reservoir conditions. Following CO2 breakthrough, samples showed sharp drops in pH (6.5–5.7), pronounced increases in alkalinity (100–3000 mg/L as HCO3) and Fe (30–1100 mg/L), and significant shifts in the isotopic compositions of H2O, dissolved inorganic carbon (DIC), and CH4. Geochemical modeling indicates that brine pH would have dropped lower but for the buffering by dissolution of carbonate and iron oxyhydroxides. This rapid dissolution of carbonate and other minerals could ultimately create pathways in the rock seals or well cements for CO2 and brine leakage. Dissolution of minerals, especially iron oxyhydroxides, could mobilize toxic trace metals and, where residual oil or suitable organics are present, the injected CO2 could also mobilize toxic organic compounds. Environmental impacts could be major if large brine volumes with mobilized toxic metals and organics migrated into potable groundwater. The δ18O values for brine and CO2 samples indicate that supercritical CO2 comprises ∼50% of pore-fluid volume ∼6 mo after the end of injection. Postinjection sampling, coupled with geochemical modeling, indicates that the brine gradually will return to its preinjection composition.

Measuring resistivity changes from within a first cased well to monitor fluids injected into oil bearing geological formations from a second cased well while passing electrical current between the two cased wells

DOEpatents

Vail, III, William B.

1993-01-01

A.C. current is conducted through geological formations separating two cased wells in an oil field undergoing enhanced oil recovery operations such as water flooding operations. Methods and apparatus are disclosed to measure the current leakage conducted into a geological formation from within a first cased well that is responsive to fluids injected into formation from a second cased well during the enhanced oil production activities. The current leakage and apparent resistivity measured within the first cased well are responsive to fluids injected into formation from the second cased well provided the distance of separation between the two cased wells is less than, or on the order of, a Characteristic Length appropriate for the problem.

Measuring resistivity changes from within a first cased well to monitor fluids injected into oil bearing geological formations from a second cased well while passing electrical current between the two cased wells

DOEpatents

Vail, W.B. III.

1993-02-16

A.C. current is conducted through geological formations separating two cased wells in an oil field undergoing enhanced oil recovery operations such as water flooding operations. Methods and apparatus are disclosed to measure the current leakage conducted into a geological formation from within a first cased well that is responsive to fluids injected into formation from a second cased well during the enhanced oil production activities. The current leakage and apparent resistivity measured within the first cased well are responsive to fluids injected into formation from the second cased well provided the distance of separation between the two cased wells is less than, or on the order of, a Characteristic Length appropriate for the problem.

Mineralogy, alteration patterns, geochemistry, and fluid properties of the Ag-Au epithermal deposit Nová Baňa, Slovakia

NASA Astrophysics Data System (ADS)

Majzlan, Juraj; Berkh, Khulan; Kiefer, Stefan; Koděra, Peter; Fallick, Anthony E.; Chovan, Martin; Bakos, František; Biroň, Adrián; Ferenc, Štefan; Lexa, Jaroslav

2018-02-01

In this contribution, we report new data on mineralogy, alteration patterns, geochemistry, fluid properties and source of fluids for the deposit Nová Baňa, one of the smaller epithermal deposits in the Middle Miocene Štiavnica andesite stratovolcano (Western Carpathians, Slovakia). Ore veins and the associated rocks were studied in samples from outcrops and old mines, grab samples, and bore holes from the central part of the deposit (ore structures Althandel, Jozef, Jakub, Vavrinec), northern part (Freischurf), SE part (Gupňa) and SW part (Šibeničný vrch). Pervasive hydrothermal alteration transformed the rock-forming minerals into a mixture of adularia and fine-grained quartz, with lesser amount of pyrite, Ti oxides and Fe oxides. This assemblage was further altered to omnipresent interstratified illite/smectite that was used in this study as a geothermometer, corroborating the results from the fluid inclusion work. Ore minerals comprise predominantly pyrite, sphalerite, galena but all sulfides are relatively sparse in the samples studied. Minerals of precious metals are electrum, Ag-tetrahedrite, acanthite, members of the polybasite-pearceite and pyrargyrite-proustite solid solution, and rare miargyrite, Hg-Ag tetrahedrite, and diaphorite. In the central part, we have found also some stibnite. In the SE part of the deposit, acanthite, uytenbogaardtite, and petrovskaite occur and seem to be related to supergene enrichment of the ores. In bulk ore samples, Zn usually dominates over Pb and Cu. The average Ag:Au ratio for the entire deposit is 64:1. The concentrations of precious metals in the grab samples reach maxima of 50 ppm Au and 570 ppm Ag in the SE part and 116 ppm Au and 1110 ppm Ag in the central part of the deposit. Fluid inclusions show signs of trapping of a heterogeneous fluid. In the central, northern and SE parts of the deposit, homogenization temperatures of 190-260 °C and consistently low salinities of <5 wt% NaCl eq were recorded. In the SW part, primary fluid inclusions gave homogenization temperatures of 160-180 °C and similar low salinities. The secondary inclusions, however, show salinities up to 24 wt% NaCl eq., interpreted as fluid boiling almost to dryness. Isotopic composition of quartz and clay minerals is recalculated to fluid composition of -5.6 to -0.6 ‰ δ18Ofluid and -80 to -36 ‰ δDfluid, indicating mixed character of hydrothermal fluids falling between the compositions of magmatic and meteoric waters, with predominance of meteoric waters. Assuming hydrostatic pressure in the fluids, the measured data suggest paleodepths of ore formation of 50-170 m in the SW part of the ore deposit, 130-420 m in the SE and N parts, and a range of 120-470 m for the central part. These observations, comparison with other epithermal deposits in the Central Slovak volcanic field, and additional data from published literature show that Nová Baňa is a low- to intermediate sulfidation epithermal deposit, genetically associated to late rhyolitic volcanic activity in this area.

FLUID EVOLUTION AND MINERAL REACTIONS DURING SHEAR ZONE FORMATION AT NUSFJORD, LOFOTEN, NORWAY (Invited)

NASA Astrophysics Data System (ADS)

Kullerud, K.

2009-12-01

At Nusfjord in Lofoten, Norway, three 0.3 - 3 m thick shear zones occur in a gabbro-anorthosite. During deformation, the shear zones were infiltrated by a hydrous fluid enriched in Cl. In the central parts of the shear zones, fluid-rock interaction resulted in complete break-down of the primary mafic silicates. Complete hydration of these minerals to Cl-free amphibole and biotite suggests that the hydrous fluid was present in excess during deformation in these parts of the shear zones. Along the margins of the shear zones, however, the igneous mafic silicates (Cpx, Bt, Opx) were only partly overgrown by hydrous minerals. Here, Cl-enriched minerals (Amph, Bt, Scp, Ap) can be observed. Amphibole shows compositions covering the range 0.1 - 4.0 wt % Cl within single thin sections. Mineral textures and extreme compositional variations of the Cl-bearing minerals indicate large chemical gradients of the fluid phase. Relics of primary mafic silicates and compositionally zoned reaction coronas around primary mafic silicates suggest that the free fluid was totally consumed before the alteration of the primary phases were completed. The extreme variations in the Cl-content of amphibole are inferred to monitor a gradual desiccation of the Cl-bearing grain-boundary fluid during fluid-mineral reactions accordingly: 1) The first amphibole that formed during the reactions principally extracted water from the fluid, resulting in a slight increase in the Cl content of the fluid. 2) Continued amphibole-forming reactions resulted in gradual consumption of the free fluid phase, principally by extracting water from the fluid, resulting in an increase in its Cl-content. Higher Cl-content of the fluid resulted in higher Cl-content of the equilibrium amphibole. 3) The most Cl-enriched amphibole (4 wt % Cl) formed in equilibrium with the last volumes of the grain-boundary fluid, which had evolved to a highly saline solution. Mineral reactions within a 1-2 thick zone of the host rock along the contact to the shear zones indicate a more complicated involvement of fluids during shear zone formation than described above. Apparently, fluids have been transported laterally from the outer parts of the shear zones into the gabbro-anorthosite along thin recrystallized zones of plagioclase. The fluid that infiltrated the undeformed host rock of the shear zones resulted in formation of Cl-free amphibole and garnet between the primary mafic minerals and plagioclase. A working hypothesis is that narrow fractures formed within the host rock, outside the sheared rock during shear zone formation. During shear zone formation, the central parts of the shear zones were completely hydrated by an externally derived Cl-bearing hydrous fluid. Some of the fluid migrated to the marginal parts of the shear zones and evolved to a highly saline solution. However, during desiccation of the fluid along the marginal parts of the shear zones, some of the fluid escaped along narrow fractures into the host rock of the shear zones. The Cl-free amphibole that formed from this fluid suggests that the narrow pathways of the fluid provided a path for water transport, but acted as a filter for the much larger ions of Cl.

Geochemical characteristics of the barite deposits at cold seeps from the northern Gulf of Mexico continental slope

NASA Astrophysics Data System (ADS)

Feng, Dong; Roberts, Harry H.

2011-09-01

Although less common than the occurrence of authigenic carbonate, barite has been observed frequently at cold seeps on continental margins worldwide. It is understood that barite forms by the interaction of barium-rich and sulfate-free seeping fluids with dissolved sulfate of pore water near the seafloor, but questions remain about the geochemical processes and mode(s) of the barite formation. Here, we report geochemical characteristics of barite deposits at 11 cold seep locations from the northern Gulf of Mexico continental slope. Samples from these sites of fluid and gas expulsion provide environmental information on barite formation. Seafloor observations and samples acquired indicate that barites occur as chimneys, cones, crusts, irregular mound-like buildups up to 2-meters high, and as a material disseminated in host sediment. Most barite samples are white-to-gray and usually have a porous fabric and layered internal structure. Mineralogically, samples of barite may contain a significant amounts of carbonate minerals, such as calcite and dolomite, but aragonite is absent in all samples analyzed in this study. Negative δ 13C values (as low as - 46.4‰ V-PDB) of the associated carbonates strongly suggests that methane is the primary carbon source. The δ 34S and δ 18O values of the barites have large variations, ranging from 18‰ to 80.4‰ V-CDT, and 7.5‰ to 26.7‰ V-SMOW, respectively. On δ 34S versus δ 18O plots, many barite deposits show a linear trend that projects down toward the isotopic composition of seawater sulfate. The trend suggests that barite formed from seawater sulfate that has been isotopically modified to varying degrees by biological sulfate reduction. The δ 34S/δ 18O ratios vary between 2.4 and 4.1. The variations are interpreted to reflect local controls on the flux of barium-rich seep fluids, changes in the rate of bacterial sulfate reduction, and/or the openness of pore fluid system. The 87Sr/ 86Sr values of the barites indicate that within-site variation is small (< 0.00026) although there is a considerable range of Sr isotopic variations across multiple geographic sites (from 0.70782 to 0.71005). The observed variations probably reflect local controls on the source(s) and diagenetic evolution of seeping fluids. Strong deviation of the Sr isotope ratios of barites from coeval seawater ( 87Sr/ 86Sr = 0.70917) is interpreted as the modification of the strontium from less radiogenic sources like older marine sediments or more radiogenic terrigenous material such as basinal brine and/or meteoric water. The new results further offer a better understanding of the origin and geochemical history of barite deposits that occur in geological record on the basis of δ 34S and δ 18O compositions.

In situ oxidation of subsurface formations

DOEpatents

Beer, Gary Lee [Houston, TX; Mo, Weijian [Sugar Land, TX; Li, Busheng [Houston, TX; Shen, Chonghui [Calgary, CA

2011-01-11

Methods and systems for treating a hydrocarbon containing formation described herein include providing heat to a first portion of the formation from a plurality of heaters in the first portion, producing produced through one or more production wells in a second portion of the formation, reducing or turning off heat provided to the first portion after a selected time, providing an oxidizing fluid through one or more of the heater wells in the first portion, providing heat to the first portion and the second portion through oxidation of at least some hydrocarbons in the first portion, and producing fluids through at least one of the production wells in the second portion. The produced fluids may include at least some oxidized hydrocarbons produced in the first portion.

Fluid transport container

DOEpatents

DeRoos, Bradley G.; Downing, Jr., John P.; Neal, Michael P.

1995-01-01

An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitment for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container.

Heating systems for heating subsurface formations

DOEpatents

Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

2011-04-26

Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

Raman and micro-thermometric investigation of the fluid inclusions in quartz in a gold-rich formation from Lepaguare mining district (Honduras, Central America).

PubMed

Bersani, D; Salvioli-Mariani, E; Mattioli, M; Menichetti, M; Lottici, P P

2009-08-01

Fluid inclusions in the quartz crystals present in gold-rich veins from central Honduras have been studied by means of micro-thermometry and micro-Raman spectroscopy in order to provide information on the physico-chemical conditions and chemical composition of the mineralizing fluids. The use of a confocal micro-Raman apparatus allowed to obtain information on the fluid composition, in particular on the gas phase, minimizing the contributions of the host matrix to the Raman signal. The samples studied were collected from an area (Lepaguare mining district, Northern-Central Honduras) rich in ore deposits due to the Cenozoic magmatic activity, where the gold and sulphide mineralization is connected with a system of quartz veins (few decimetres thick) occurring in low-grade metamorphic rocks and produced by hydrothermal fluids. The quartz crystals present in the gold-rich veins often contain fluid inclusions. Four types of fluid inclusions have been observed, but their assemblage in the same clusters and fracture systems, as well as their comparable salinity and homogenization data, suggest that they have the same origin. Micro-thermometry and Raman spectroscopy provide a composition of the mineralizing fluids attributable to the system H(2)O-NaCl-KCl-CO(2)-CH(4), with temperature and pressure intervals of 210-413 degrees C and 1050-3850 bar, respectively. These data agree with an epigenetic origin of the gold deposit (depth < 6 km) related to granitoid or granodiorite intrusions associated to orogenic environments.

Association of gas hydrate formation in fluid discharges with anomalous hydrochemical profiles

NASA Astrophysics Data System (ADS)

Matveeva, T.

2009-04-01

Numerous investigations worldwide have shown that active underwater fluid discharge produces specific structures on the seafloor such as submarine seepages, vents, pockmarks, and collapse depressions. Intensive fluxes of fluids, especially of those containing hydrocarbon gases, result in specific geochemical and physical conditions favorable for gas hydrate (GH) formation. GH accumulations associated with fluid discharge are usually controlled by fluid conduits such as mud volcanoes, diapirs or faults. During last decade, subaqueous GHs become the subject of the fuel in the nearest future. However, the expediency of their commercial development can be proved solely by revealing conditions and mechanisms of GH formation. Kinetic of GH growth (although it is incompletely understood) is one of the important parameters controlling their formation among with gas solubility, pressure, temperature, gas quantity and others. Original large dataset on hydrate-related interstitial fluids obtained from different fluid discharge areas at the Sea of Okhotsk, Black Sea, Gulf of Cadiz, Lake Baikal (Eastern Siberia) allow to suggest close relation of the subaqueous GH formation process to anomalous hydrochemical profiles. We have studied the chemical and isotopic composition of interstitial fluids from GH-bearing and GH-free sediments obtained at different GH accumulations. Most attention was paid to possible influence of the interstitial fluid chemistry on the kinetic of GH formation in a porous media. The influence of salts on methane solubility within hydrate stability zones was considered by Handa (1990), Zatsepina & Buffet (1998), and later by Davie et al. (2004) from a theoretical point of view. Our idea is based on the experimentally proved fact that fugacity coefficient of methane dissolved in saline gas-saturated water which is in equilibrium with hydrates, is higher than that in more fresh water though the solubility is lower. Therefore, if a gradient of water salinity exist under conditions of hydrate stability, diffusion of methane induces hydrate formation by segregation on the outside a boundary fresher/saline water. Geochemical analysis of the interstitial fluids was used to define the mechanisms of GH accumulation and spatial distribution pattern of GHs in sediments from gas seeps abundant off NE Sakhaline Island (Sea of Okhotsk) (Matveeva et al., 2005; Mazurenko et al., submitted). A model of the ascending fluid discharge along one of the seeps named CHAOS was made based on the measured chlorinity (salinity function) of the pore waters and calculated chlorinity gradients. The chloride ion distributionprofiles with depth at the CHAOS site represent alike increasing and decreasing trends both in hydrate-bearing and hydrate-free cores. The model testifies an upward water infiltration of more saline water in vicinity of coring stations recovered GHs and relatively desalinated water mostly around those hydrate-free. It was established that GH formation at the CHAOS site is focused at the locations of intensive ascending flow of water enriched by salts that is probably function of gas solubility in water in the equilibrium with hydrate supposing that the feature is responsible for the hydrate formation just at the locations of the saline water up flows (other conditions being equal). Another case study supporting direct relation of GH formation with anomalous fluids and possible GH formation just on the interface of water flows with different salinity (defining chemical potentials of the water) is fresh-water GH accumulation at the Malenkiy fluid vent in the southern basin of Lake Baikal (Matveeva et al., 2003). The GH accumulation characterizes by heterogeneity in the spatial distribution of GH within a very small vent area. The spatial distribution of the GH-bearing and gas-saturated sediments suggests that several small fluid vents exist within the Malenkiy structure. Based on coring results, the size of these vents should not exceed a few meters. Interstitial water chemistry data indicates that water discharged within the Malenkiy vent is enriched with salts, especially Ca, Cl, and SO4 ions. The ascending water delivering gas into the GH stability zone is thought to be the main GH-forming fluid. Geochemical data suggest that the GH in the subsurface sediments of Lake Baikal originated from a deep source of water with anomalous composition assumed to be derived from buried paleolakes. As a whole, the GH accumulation corresponds to the area of the Malenkiy structure and is represented by several small scale GH occurrences coincident with local fluid discharge manifestations. The data obtained may serve as useful tool for development of geological and hydrogeochemical models of separate GH accumulations forming in the fluid discharge areas. The models on may also serve as a base for the gas inventory of the GH accumulations.

Increased negatively of interstitial fluid pressure in rat skin contributes to the edema formation induced by Zymosan.

PubMed

Ostgaard, G; Reed, R K

1993-11-01

Increased negatively of interstitial fluid pressure (Pif) contributes to rapid edema formation in several acute inflammatory reactions attesting to an "active" role for the loose connective tissues in the transcapillary fluid exchange and edema formation under these circumstances. The present study reports the effect of the complement activator Zymosan on Pif, transcapillary fluid, and albumin flux. Micropipettes (tip diameter 5 to 7 microns) connected to a servo-controlled counterpressure system were used to measure Pif in rat dermis. When compared to saline injection, subdermal injection of 1 mg Zymosan in 10 microliters 0.15 M NaCl increased total tissue water by 1.6 ml/g dry weight in 5 min, corresponding to about 150% increase in interstitial fluid volume. Pif increased from +0.4 to +3.7 mm Hg. Increased negativity of Pif can be masked by the edema formation which will increase Pif. Measurements were therefore also performed after circulatory arrest, when transcapillary fluid flux and edema formation are abolished. Using this experimental protocol Pif fell from +0.3 mm Hg to -2.5 mm Hg 5 min after subdermal injection of Zymosan and remained at this level throughout the observation period of 90 min. Injection of saline alone after circulatory arrest increased Pif transiently by about 1 mm Hg. Thus, subdermal injection of Zymosan causes increased negativity of Pif by about 4 mm Hg. Although the lowering of Pif itself will explain a minor part of the increased fluid filtration, the results attest to the role of loose connective tissues being active in the edema-generating process also in the inflammatory reaction induced by Zymosan.

Microbial Enrichment from Six Hydraulic Fracturing Fluids and Biogeochemical Characteristics of Flowback Waters in Oklahoma Shale Formations

NASA Astrophysics Data System (ADS)

Krzmarzick, M. J.; McCutchan, A.; Carroll, J.; Lozano, T.

2017-12-01

Hydraulic fracturing of oil and gas formations has revolutionized the industry, but little is known regarding the interactions of the microbiology in formations and the hydraulic fracturing chemicals used. In the first part of this study, six representative hydraulic fracturing fluids were incubated in bench scale microcosms with surface soils over six months at 1× concentrations used in the field. These fluids differed greatly in terms of biocide, surfactants, corrosion inhibitors and crosslinking agents (if any). The changes in microbial communities were measured by Illumina 16S rRNA gene analysis and quantitative-PCR. As a whole, the microbial communities enriched were significantly varied between fluids, with the magnitude of the difference tightly linked to the total organic carbon of each fluid. Most enriched bacteria heavily grew within just the first couple of weeks, and belonged to genera well-linked to xenobiotic degradation, such as Azospirillum, Ralstonia, and Comamonas. This, combined with bulk parameters such as chemical oxygen demand of the water, indicates that a significant fraction of these fluids are readily degradable, though individual chemicals were not monitored for recalcitrance. In the second component of this work, the flowback waters from sixteen newly completed wells in south-central Oklahoma were monitored over two months for compositions of boron, dissolved solids, BTEX, chloride, and their microbial communities. As expected, dissolved solids increased over time as the flowback waters became more characteristic of the formation waters. In these wells, boron, a carefully measured component of the fracturing fluid for cross-linking applications, was either stable or increased over time. The microbial community characteristics are pending but will be compared between formations, to the chemical data, and to the results in the bench-top degradation study.

Formation of a wave on an ice-sheet above the dipole, moving in a fluid

NASA Astrophysics Data System (ADS)

Il'ichev, A. T.; Savin, A. A.; Savin, A. S.

2012-05-01

Theory of wave motions of a fluid with an ice-sheet was developed due to the necessity of solving of a number of problems of marine and land physics. The main attention in these investigations was focused on propagation and interaction of free waves, and also on appearance of waves under action of different loadings on the ice-sheet. From the other side, the problems dealing with waves on the fluid surface, free from the ice due to motion in the mass of the fluid of rigid bodies, has the known solutions. In this connection, it seems natural to disserminate the formulation and methods of such problems to the case of the fluid with the ice-sheet. In the present note we describe the character of formation of waves from the singularity, localized in the fluid of infinite depth beneath the ice-sheet. We use the example of the dipole, which models a cylinder in the infinite mass of the fluid. The character of the formation does not depend on the type of singularity. The ice-sheet is considered as a thin elastic plate of a constant width, floating on the water surface.

Geochemical constraints on the half-life of {sup 130}Te

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, H. V.; Pattrick, R. A. D.; Crowther, S. A.

2008-11-15

To determine the half-life of {sup 130}Te we have analyzed multiple aliquots of geological telluride samples 100 times smaller than those previously reported using a unique resonance ionization mass spectrometer. We employ a low-fluence neutron irradiation that allows determination of parent and daughter from the same xenon isotopic analysis. Step heating of these irradiated samples allows the {sup 130}Xe/{sup 132}Xe ratio of fluids trapped inside the tellurides to be determined. Considering only samples where the trapped {sup 130}Xe/{sup 132}Xe ratio is demonstrably consistent with atmospheric xenon, we can avoid over- or under-estimating the half-life due to redistribution or inheritance ofmore » radiogenic {sup 130}Xe. Combining our work with literature data, it is clear that several relatively young samples have retained xenon quantitatively since formation, allowing the half-life to be determined as (8.0{+-}1.1)x10{sup 20} yr. Older samples have clearly been affected by post-formation processing. This suggests that there is little hope of monitoring solar luminosity through the geological record of {sup 126}Xe production by solar neutrinos, but it is possible that geologically useful chronological information can be obtained from this system.« less

The risk of renal stone formation during and after long duration space flight

NASA Technical Reports Server (NTRS)

Whitson, P. A.; Pietrzyk, R. A.; Morukov, B. V.; Sams, C. F.

2001-01-01

BACKGROUND: The formation of a renal stone during space flight may have serious negative effects on the health of the crewmember and the success of the mission. Urinary biochemical factors and the influence of dietary factors associated with renal stone development were assessed during long duration Mir Space Station missions. METHODS: Twenty-four-hour urine samples were collected prior to, during and following long duration space flight. The relative urinary supersaturation of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were determined. RESULTS: Changes in the urinary biochemistry of crewmembers during long duration spaceflight demonstrated increases in the supersaturation of the stone-forming salts. In-flight hypercalciuria was evident in a number of individual crewmembers and 24-hour dietary fluid intake and urine volume were significantly lower. During flight, there was a significant increase in brushite supersaturation. CONCLUSIONS: These data suggest acute effects of space flight and postflight changes in the urinary biochemistry favoring increased crystallization in the urine. The effects of dietary intake, especially fluid intake, may have a significant impact on the potential for renal stone formation. Efforts are now underway to assess the efficacy of a countermeasure to mitigate the increased risk. Copyright 2001 S. Karger AG, Basel.

Offline solid phase microextraction sampling system

DOEpatents

Harvey, Chris A.

2008-12-16

An offline solid phase microextraction (SPME) sampling apparatus for enabling SPME samples to be taken a number of times from a previously collected fluid sample (e.g. sample atmosphere) stored in a fused silica lined bottle which keeps volatile organics in the fluid sample stable for weeks at a time. The offline SPME sampling apparatus has a hollow body surrounding a sampling chamber, with multiple ports through which a portion of a previously collected fluid sample may be (a) released into the sampling chamber, (b) SPME sampled to collect analytes for subsequent GC analysis, and (c) flushed/purged using a fluidically connected vacuum source and purging fluid source to prepare the sampling chamber for additional SPME samplings of the same original fluid sample, such as may have been collected in situ from a headspace.

Oral fluid vs. Urine Analysis to Monitor Synthetic Cannabinoids and Classic Drugs Recent Exposure

PubMed Central

Blandino, Vincent; Wetzel, Jillian; Kim, Jiyoung; Haxhi, Petrit; Curtis, Richard; Concheiro, Marta

2018-01-01

Background Urine is a common biological sample to monitor recent drug exposure, and oral fluid is an alternative matrix of increasing interest in clinical and forensic toxicology. Limited data are available about oral fluid vs. urine drug disposition, especially for synthetic cannabinoids. Objective To compare urine and oral fluid as biological matrices to monitor recent drug exposure among HIV-infected homeless individuals. Methods Seventy matched urine and oral fluid samples were collected from 13 participants. Cannabis, amphetamines, benzodiazepines, cocaine and opiates were analyzed in urine by the enzyme-multiplied-immunoassay-technique and in oral fluid by liquid chromatography tandem mass spectrometry (LC-MSMS). Eleven synthetic cannabinoids were analyzed in urine and in oral fluid by LC-MSMS. Results Five oral fluid samples were positive for AB-FUBINACA. In urine, 4 samples tested positive for synthetic cannabinoids PB-22, 5-Fluoro-PB-22, AB-FUBINACA, and metabolites UR-144 5-pentanoic acid and UR-144 4-hydroxypentyl. In only one case, oral fluid and urine results matched, both specimens being AB-FUBINACA positive. For cannabis, 40 samples tested positive in urine and 30 in oral fluid (85.7% match). For cocaine, 37 urine and 52 oral fluid samples were positive (75.7% match). Twenty-four urine samples were positive for opiates, and 25 in oral fluid (81.4% match). For benzodiazepines, 23 samples were positive in urine and 25 in oral fluid (85.7% match). Conclusion/Discussion These results offer new information about drugs disposition between urine and oral fluid. Oral fluid is a good alternative matrix to urine for monitoring cannabis, cocaine, opiates and benzodiazepines recent use; however, synthetic cannabinoids showed mixed results. PMID:29173162

Oral Fluid vs. Urine Analysis to Monitor Synthetic Cannabinoids and Classic Drugs Recent Exposure.

PubMed

Blandino, Vincent; Wetzel, Jillian; Kim, Jiyoung; Haxhi, Petrit; Curtis, Richard; Concheiro, Marta

2017-01-01

Urine is a common biological sample to monitor recent drug exposure, and oral fluid is an alternative matrix of increasing interest in clinical and forensic toxicology. Limited data are available about oral fluid vs. urine drug disposition, especially for synthetic cannabinoids. To compare urine and oral fluid as biological matrices to monitor recent drug exposure among HIV-infected homeless individuals. Seventy matched urine and oral fluid samples were collected from 13 participants. Cannabis, amphetamines, benzodiazepines, cocaine and opiates were analyzed in urine by the enzyme-multipliedimmunoassay- technique and in oral fluid by liquid chromatography tandem mass spectrometry (LCMSMS). Eleven synthetic cannabinoids were analyzed in urine and in oral fluid by LC-MSMS. Five oral fluid samples were positive for AB-FUBINACA. In urine, 4 samples tested positive for synthetic cannabinoids PB-22, 5-Fluoro-PB-22, AB-FUBINACA, and metabolites UR-144 5-pentanoic acid and UR-144 4-hydroxypentyl. In only one case, oral fluid and urine results matched, both specimens being AB-FUBINACA positive. For cannabis, 40 samples tested positive in urine and 30 in oral fluid (85.7% match). For cocaine, 37 urine and 52 oral fluid samples were positive (75.7% match). Twenty-four urine samples were positive for opiates, and 25 in oral fluid (81.4% match). For benzodiazepines, 23 samples were positive in urine and 25 in oral fluid (85.7% match). These results offer new information about drugs disposition between urine and oral fluid. Oral fluid is a good alternative matrix to urine for monitoring cannabis, cocaine, opiates and benzodiazepines recent use; however, synthetic cannabinoids showed mixed results. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

FTIR absorption reflection study of biomimetic growth of phosphates on titanium implants

NASA Astrophysics Data System (ADS)

Stoch, A.; Jastrzębski, W.; Brożek, A.; Stoch, J.; Szaraniec, J.; Trybalska, B.; Kmita, G.

2000-11-01

Titanium has been used for many medical applications; however, its joining to a living bone still is not satisfactorily good, challenging appropriate investigations. The aim of this work was to generate chemical modifications at its surface such that in vivo conditions, heterogeneous nucleation, and then growth of apatite from the body fluid could be easily induced and successfully performed. For this purpose, on the titanium samples, the oxide sublayers containing titanium, calcium and silicon (TCS) were deposited from a suitable solution using the sol-gel deep-coating procedure. Dried samples were heated at 400°C then cooled and thermostatically held in synthetic body fluids (SBF, SBFIII) under physiological conditions to mimic the natural process of apatite formation. Changes in surface composition of TCS sublayers caused by the heating were studied with XPS. Infrared spectroscopy and scanning electron microscopy monitored successive steps of apatite growth. It was found that in SBF, at the precoated titanium surface, nucleation and growth of the apatite containing carbonate took place. In SBFIII, for a higher concentration of calcium ions in comparison with SBF, a much-enhanced growth of the apatite free of carbonate was observed. TCS precoatings applied on stainless steel and Cr-Co-Mo alloy (Micromed) act also as bioactive interfaces with high ability to nucleation of biologically equivalent apatite. Biomimetic formation of this apatite on biologically inactive materials can be an important step in implant surgery.

Formation of intermetallic phases in AlSi7Fe1 alloy processed under microgravity and forced fluid flow conditions and their influence on the permeability

NASA Astrophysics Data System (ADS)

Steinbach, S.; Ratke, L.; Zimmermann, G.; Budenkova, O.

2016-03-01

Ternary Al-6.5wt.%Si-0.93wt.%Fe alloy samples were directionally solidified on-board of the International Space Station ISS in the ESA payload Materials Science Laboratory (MSL) equipped with Low Gradient Furnace (LGF) under both purely diffusive and stimulated convective conditions induced by a rotating magnetic field. Using different analysis techniques the shape and distribution of the intermetallic phase β-Al5SiFe in the dendritic microstructure was investigated, to study the influence of solidification velocity and fluid flow on the size and spatial arrangement of intermetallics. Deep etching as well as 3-dimensional computer tomography measurements characterized the size and the shape of β-Al5SiFe platelets: Diffusive growth results in a rather homogeneous distribution of intermetallic phases, whereas forced flow promotes an increase in the amount and the size of β-Al5SiFe platelets in the centre region of the samples. The β-Al5SiFe intermetallics can form not only simple platelets, but also be curved, branched, crossed, interacting with dendrites and porosity located. This leads to formation of large and complex groups of Fe-rich intermetallics, which reduce the melt flow between dendrites leading to lower permeability of the mushy zone and might significantly decrease feeding ability in castings.

Gypsum, jarosite, and hydrous iron-phosphate in Martian meteorite Roberts Massif 04262: Implications for sulfate geochemistry on Mars.

NASA Astrophysics Data System (ADS)

Greenwood, J. P.

2008-12-01

Gypsum has been identified on Mars by MEX OMEGA [1] and jarosite identified via MER-B lander [2] and both minerals are examples of the importance of calcium and iron sulfates in Martian weathering processes. The weathering of Martian basalt to form Ca and iron sulfates should be an important process on Mars. Martian jarosite has been identified in MIL 03346 [3] and Ca-sulfate has been identified in EETA 79001 [4], but both phases have yet to be identified in the same Martian sample. In Roberts Massif 04262, an olivine-phyric shergottite, iron-sulfide and calcium-phosphate minerals are undergoing reaction (dissolution and reprecipitation?) to form gypsum, jarosite, and an iron-phosphate phase, presumably during the meteorite's residence in Antarctica. If true, then an acidic and oxidizing fluid was present in this meteorite, due to the formation of jarosite which requires fluid of this type to form [5]. The weathering of iron-sulfides on Earth to form acidic and oxidizing fluids is common, thus this can be reconciled with the formation of an acidic fluid in a basic rock. Presumably, under more extensive weathering of silicate minerals in Martian basalt, the pH would be raised to values where jarosite would not be stable. While the weathering of RBT 04262 is likely occurring in Antarctica, a similar susceptibility of the apatite and pyrrhotite to incipient weathering on Mars may be expected. Oxidizing crustal fluids on Mars may attack iron- sulfides first in Martian basalts. The weathering of iron-sulfides leads to increasing acidity of fluids, which would enhance the dissolution of the calcium-phosphate minerals [6]. The formation of jarosite, gypsum, and iron-phosphate minerals during the early stages of weathering of Martian basalts may be an important process on Mars globally. [1] Gendrin, A. et al. (2005) Science, 307, 1587-1591. [2] Klingelhöfer et al. (2004) Science, 306, 1740- 1745. [3] Vicenzi E. P. et al. (2007) LPSC XXXVIII, Abstract 2335. [4] Gooding J. L. et al. (1988) GCA, 52, 909-915. [5] Greenwood J. P. et al. (2005) LPSC XXXVI, Abstract 2348. [6] Greenwood J. P. and Blake R. E. (2006) Geology, 34, 953-956.

Mechanisms for the Crystallization of ZBLAN

NASA Technical Reports Server (NTRS)

Ethridge, Edwin C.; Tucker, Dennis S.; Kaukler, William; Antar, Basil

2003-01-01

The objective of this ground based study is to test the hypothesis that shear thinning (the non-Newtonian response of viscosity to shear rate) is a viable mechanism to explain the observation of enhanced glass formation in numerous low-g experiments. In 1-g, fluid motion results from buoyancy forces and surface tension driven convection. This fluid flow will introduce shear in undercooled liquids in 1-g. In low-g it is known that fluid flows are greatly reduced so that the shear rate in fluids can be extremely low. It is believed that some fluids may have weak structure in the absence of flow. Very small shear rates could cause this structure to collapse in response to shear resulting in a lowering of the viscosity of the fluid. The hypothesis of this research is that: Shear thinning in undercooled liquids decreases the viscosity, increasing the rate of nucleation and crystallization of glass forming melts. Shear in the melt can be reduced in low-g, thus enhancing undercooling and glass formation. The viscosity of a model glass (lithium di-silicate, L2S) often used for crystallization studies has been measured at very low shear rates using a dynamic mechanical thermal analyzer. Our results are consistent with increasing viscosity with a lowering of shear rates. The viscosity of L2S may vary as much as an order of magnitude depending on the shear rate in the temperature region of maximum nucleation and crystal growth. Classical equations for nucleation and crystal growth rates, are inversely related to the viscosity and viscosity to the third power respectively. An order of magnitude variation in viscosity (with shear) at a given temperature would have dramatic effects on glass crystallization Crystallization studies with the heavy metal fluoride glass ZBLAN (ZrF2-BaF2-LaF3-AlF3-NaF) to examine the effect of shear on crystallization are being initiated. Samples are to be melted and quenched under quiescent conditions at different shear rates to determine the effect on crystallization. The results from this study are expected to advance the current scientific understanding of glass formation in low-g and glass crystallization under glass molding conditions and will improve the scientific understanding of technological processes such as fiber pulling, bulk amorphous alloys, and glass fabrication processes.

Vortex formation through inertial wave focusing

NASA Astrophysics Data System (ADS)

Duran-Matute, Matias; Flor, Jan-Bert; Godeferd, Fabien

2011-11-01

We present a novel experimental and numerical study on the formation of columnar vortical structures by inertial waves in a rotating fluid. Two inertial-wave cones are generated by a vertically oscillating torus in a fluid in solid body rotation At the tip of the cones, there is a singular point towards which the energy of the waves gets focused. The particularity of this configuration, as compared to those of previous experiments (e.g. oscillating sphere or disc), is that the singular point's position within the fluid leads to complex non-linear wave interaction, which may lead to the formation of a localized vortex that expands in the vertical in the form of a Taylor column. Using detailed PIV measurements we consider the flow evolution from the localized wave overturning motion to the Taylor column formation as well as the inertial wave dynamics during this process, The results are discussed in the context of turbulence in rotating fluids. We acknowledge financial support from projects ANR ANISO and CIBLE.

Accelerated gravity testing of aquitard core permeability and implications at formation and regional scale

NASA Astrophysics Data System (ADS)

Timms, W. A.; Crane, R.; Anderson, D. J.; Bouzalakos, S.; Whelan, M.; McGeeney, D.; Rahman, P. F.; Acworth, R. I.

2016-01-01

Evaluating the possibility of leakage through low-permeability geological strata is critically important for sustainable water supplies, the extraction of fuels from coal and other strata, and the confinement of waste within the earth. The current work demonstrates that relatively rapid and realistic vertical hydraulic conductivity (Kv) measurements of aquitard cores using accelerated gravity can constrain and compliment larger-scale assessments of hydraulic connectivity. Steady-state fluid velocity through a low-K porous sample is linearly related to accelerated gravity (g level) in a centrifuge permeameter (CP) unless consolidation or geochemical reactions occur. A CP module was custom designed to fit a standard 2 m diameter geotechnical centrifuge (550 g maximum) with a capacity for sample dimensions up to 100 mm diameter and 200 mm length, and a total stress of ˜ 2 MPa at the base of the core. Formation fluids were used as influent to limit any shrink-swell phenomena, which may alter the permeability. Kv results from CP testing of minimally disturbed cores from three sites within a clayey-silt formation varied from 10-10 to 10-7 m s-1 (number of samples, n = 18). Additional tests were focussed on the Cattle Lane (CL) site, where Kv within the 99 % confidence interval (n = 9) was 1.1 × 10-9 to 2.0 × 10-9 m s-1. These Kv results were very similar to an independent in situ Kv method based on pore pressure propagation though the sequence. However, there was less certainty at two other core sites due to limited and variable Kv data. Blind standard 1 g column tests underestimated Kv compared to CP and in situ Kv data, possibly due to deionised water interactions with clay, and were more time-consuming than CP tests. Our Kv results were compared with the set-up of a flow model for the region, and considered in the context of heterogeneity and preferential flow paths at site and formation scale. Reasonable assessments of leakage and solute transport through aquitards over multi-decadal timescales can be achieved by accelerated core testing together with complimentary hydrogeological monitoring, analysis, and modelling.

Utilizing rare earth elements as tracers in high TDS reservoir brines in CCS applications

DOE PAGES

McLing, Travis; Smith, William; Smith, Robert

2014-12-31

In this paper we report the result of research associated with the testing of a procedures necessary for utilizing natural occurring trace elements, specifically the Rare Earth Elements (REE) as geochemical tracers in Carbon Capture and Storage (CCS) applications. Trace elements, particularly REE may be well suited to serve as in situ tracers for monitoring geochemical conditions and the migration of CO₂-charged waters within CCS storage systems. We have been conducting studies to determine the efficacy of using REE as a tracer and characterization tool in the laboratory, at a CCS analogue site in Soda Springs, Idaho, and at amore » proposed CCS reservoir at the Rock Springs Uplift, Wyoming. Results from field and laboratory studies have been encouraging and show that REE may be an effective tracer in CCS systems and overlying aquifers. In recent years, a series of studies using REE as a natural groundwater tracer have been conducted successfully at various locations around the globe. Additionally, REE and other trace elements have been successfully used as in situ tracers to describe the evolution of deep sedimentary Basins. Our goal has been to establish naturally occurring REE as a useful monitoring measuring and verification (MMV) tool in CCS research because formation brine chemistry will be particularly sensitive to changes in local equilibrium caused by the addition of large volumes of CO₂. Because brine within CCS target formations will have been in chemical equilibrium with the host rocks for millions of years, the addition of large volumes of CO₂ will cause reactions in the formation that will drive changes to the brine chemistry due to the pH change caused by the formation of carbonic acid. This CO₂ driven change in formation fluid chemistry will have a major impact on water rock reaction equilibrium in the formation, which will impart a change in the REE fingerprint of the brine that can measured and be used to monitor in situ reservoir conditions. Our research has shown that the REE signature imparted to the formation fluid by the introduction of CO₂ to the formation, can be measured and tracked as part of an MMV program. Additionally, this REE fingerprint may serve as an ideal tracer for fluid migration, both within the CCS target formation, and should formation fluids migrate into overlying aquifers. However application of REE and other trace elements to CCS system is complicated by the high salt content of the brines contained within the target formations. In the United States by regulation, in order for a geologic reservoir to be considered suitable for carbon storage, it must contain formation brine with total dissolved solids (TDS) > 10,000 ppm, and in most cases formation brines have TDS well in excess of that threshold. The high salinity of these brines creates analytical problems for elemental analysis, including element interference with trace metals in Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) (i.e. element mass overlap due to oxide or plasma phenomenon). Additionally, instruments like the ICP-MS that are sensitive enough to measure trace elements down to the parts per trillion level are quickly oversaturated when water TDS exceeds much more than 1,000 ppm. Normally this problem is dealt with through dilution of the sample, bringing the water chemistry into the instruments working range. However, dilution is not an option when analyzing these formation brines for trace metals, because trace elements, specifically the REE, which occur in aqueous solutions at the parts per trillion levels. Any dilution of the sample would make REE detection impossible. Therefore, the ability to use trace metals as in situ natural tracers in high TDS brines environments requires the development of methods for pre-concentrating trace elements, while reducing the salinity and associated elemental interference such that the brines can be routinely analyzed by standard ICP-MS methods. As part of the Big Sky Carbon Sequestration Project the INL-CAES has developed a rapid, easy to use process that pre-concentrates trace metals, including REE, up to 100x while eliminating interfering ions (e.g. Ba, Cl). The process is straightforward, inexpensive, and requires little infrastructure, using only a single chromatography column with inexpensive, reusable, commercially available resins and wash chemicals. The procedure has been tested with synthetic brines (215,000 ppm or less TDS) and field water samples (up to 5,000 ppm TDS). Testing has produced data of high quality with REE capture efficiency exceeding 95%, while reducing interfering elements by > 99%.« less

Infusion fluids contain harmful glucose degradation products

PubMed Central

Bryland, Anna; Broman, Marcus; Erixon, Martin; Klarin, Bengt; Lindén, Torbjörn; Friberg, Hans; Wieslander, Anders; Kjellstrand, Per; Ronco, Claudio; Carlsson, Ola

2010-01-01

Purpose Glucose degradation products (GDPs) are precursors of advanced glycation end products (AGEs) that cause cellular damage and inflammation. We examined the content of GDPs in commercially available glucose-containing infusion fluids and investigated whether GDPs are found in patients’ blood. Methods The content of GDPs was examined in infusion fluids by high-performance liquid chromatography (HPLC) analysis. To investigate whether GDPs also are found in patients, we included 11 patients who received glucose fluids (standard group) during and after their surgery and 11 control patients receiving buffered saline (control group). Blood samples were analyzed for GDP content and carboxymethyllysine (CML), as a measure of AGE formation. The influence of heat-sterilized fluids on cell viability and cell function upon infection was investigated. Results All investigated fluids contained high concentrations of GDPs, such as 3-deoxyglucosone (3-DG). Serum concentration of 3-DG increased rapidly by a factor of eight in patients receiving standard therapy. Serum CML levels increased significantly and showed linear correlation with the amount of infused 3-DG. There was no increase in serum 3-DG or CML concentrations in the control group. The concentration of GDPs in most of the tested fluids damaged neutrophils, reducing their cytokine secretion, and inhibited microbial killing. Conclusions These findings indicate that normal standard fluid therapy involves unwanted infusion of GDPs. Reduction of the content of GDPs in commonly used infusion fluids may improve cell function, and possibly also organ function, in intensive-care patients. Electronic supplementary material The online version of this article (doi:10.1007/s00134-010-1873-x) contains supplementary material, which is available to authorized users. PMID:20397009

Synthesis and characterization of 64SiO2-26CaO-5P2O5-5CuO bioactive composition for the growth of hydroxyapatite layer by XRD, Raman and pH studies

NASA Astrophysics Data System (ADS)

Kaur, Pardeep; Singh, K. J.

2016-05-01

Bioactive sample with the nominal composition of 64SiO2-26CaO-5P2O5-5CuO has been prepared in the laboratory by using the sol-gel technique. The bioactivity of the prepared sample has been analyzed by using the Tris Simulated Body Fluid which has also been prepared in the laboratory. XRD and Raman techniques have been employedto probe the formation of hydroxyapatite layer. pH studies has also been undertaken to check the acidic/non-acidic behavior of sample. Growth of hydroxyapatite layer has been observed after one day on the surface of the sample. Moreover, sample has been observed to be non-acidic in nature.

Use of vitamin B12 in joint lavage for determination of dilution factors of canine synovial fluid.

PubMed

de Bruin, Tanya; de Rooster, Hilde; van Bree, Henri; Cox, Eric

2005-11-01

To test a modified saline (0.9% NaCl) solution joint washing (lavage) technique that includes the use of vitamin B12 as an internal marker for the evaluation of synovial fluid dilution in lavage samples from canine joints. 9 plasma samples obtained from blood samples of 9 healthy dogs and 9 synovial fluid samples aspirated from stifle joints of 9 cadaveric dogs. Photometric absorbances of 25% vitamin B12 solution, canine synovial fluid, and canine plasma were measured in a spectrophotometer to establish an optimal wavelength for analysis. Canine synovial fluid and plasma samples were mixed with the 25% vitamin B12 solution to obtain 1%, 3%, 5%, 10%, 20%, and 50% solutions of synovial fluid or plasma. Diluted synovial fluid and plasma samples were used to simulate joint lavage samples and to examine the possible interference of these substances (synovial fluid or plasma) with the absorbance of the 25% vitamin B12 solution in photometric analysis. The optimal wavelength was found to be at 550 nm. Canine synovial fluid and plasma samples did not interfere with the absorbance measurements of the 25% vitamin B12 solution up to a 50% dilution of plasma or synovial fluid. The modified saline solution joint lavage method with the use of a 25% vitamin B12 solution as an internal standard provides an accurate and reliable technique for the evaluation of synovial fluid dilution in lavage samples from canine joints.

Formation of the Wiesloch Mississippi Valley-type Zn-Pb-Ag deposit in the extensional setting of the Upper Rhinegraben, SW Germany

USGS Publications Warehouse

Pfaff, Katharina; Hildebrandt, Ludwig H.; Leach, David L.; Jacob, Dorrit E.; Markl, Gregor

2010-01-01

The Mississippi Valley-type (MVT) Zn-Pb-Ag deposit in the Wiesloch area, Southwest Germany, is controlled by graben-related faults of the Upper Rhinegraben. Mineralization occurs as vein fillings and irregular replacement ore bodies consisting of sphalerite, banded sphalerite, galena, pyrite, sulfosalts (jordanite and geocronite), barite, and calcite in the Middle Triassic carbonate host rock. Combining paragenetic information, fluid inclusion investigations, stable isotope and mineral chemistry with thermodynamic modeling, we have derived a model for the formation of the Wiesloch deposit. This model involves fluid mixing between ascending hot brines (originating in the crystalline basement) with sedimentary formation waters. The ascending brines originally had a near-neutral pH (around 6) and intermediate oxidation state, reflecting equilibrium with granites and gneisses in the basement. During fluid ascent and cooling, the pH of the brine shifted towards more acidic (around 4) and the oxidation state increased to conditions above the hematite-magnetite buffer. These chemical characteristics contrast strongly with those of the pore and fracture fluid residing in the limestone aquifer, which had a pH between 8 and 9 in equilibrium with calcite and was rather reduced due to the presence of organic matter in the limestone. Mixing between these two fluids resulted in a strong decrease in the solubility of silver-bearing sphalerite and galena, and calcite. Besides Wiesloch, several Pb-Zn deposits are known along the Upper Rhinegraben, including hydrothermal vein-type deposits like Badenweiler and the Michael mine near Lahr. They all share the same fluid origin and formation process and only differ in details of their host rock and fluid cooling paths. The mechanism of fluid mixing also seems to be responsible for the formation of other MVT deposits in Europe (e.g., Reocin, Northern Spain; Treves, Southern France; and Cracow-Silesia, Poland), which show notable similarities in terms of their age, mineralogy, and mineral chemistry to the MVT deposit near Wiesloch.

On the Formation of Rifts in Ice Shelves

NASA Astrophysics Data System (ADS)

Sayag, R.; Worster, G.

2017-12-01

Ice calving accounts for significant part in the mass loss of present ice sheets. Several processes could lead to calving, among them is the formation of rifts near the fronts of ice shelves. Here we combine laboratory-scale experiments of ice sheets together with theoretical modeling to investigate the formation of rifts in ice shelves. We model the deformation of ice with a thin viscous film that is driven axisymmetrically by buoyancy. When the viscous fluid intrudes a bath of an inviscid fluid that represents the ocean, the circular symmetry of the front breaks up into a set of tongues with a characteristic wavelength that coarsens over time, a pattern that is reminiscent of ice rifts. Theoretically, we model the formation of rifts as a hydrodynamic instability of powerlaw fluid. Our model demonstrates the formation of rifts and the coarsening of the characteristic wavelength, and predicts coarsening transition times that are consistent with our experimental measurements.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sverjensky, Dimitri A.; Huang, Fang

Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly withmore » eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.« less

Effect of pulse pressure on borehole stability during shear swirling flow vibration cementing.

PubMed

Cui, Zhihua; Ai, Chi; Lv, Lei; Yin, Fangxian

2017-01-01

The shear swirling flow vibration cementing (SSFVC) technique rotates the downhole eccentric cascade by circulating cementing fluid. It makes the casing eccentrically revolve at high speed around the borehole axis. It produces strong agitation action to the annulus fluid, makes it in the state of shear turbulent flow, and results in the formation of pulse pressure which affects the surrounding rock stress. This study was focused on 1) the calculation of the pulse pressure in an annular turbulent flow field based on the finite volume method, and 2) the analysis of the effect of pulse pressure on borehole stability. On the upside, the pulse pressure is conducive to enhancing the liquidity of the annulus fluid, reducing the fluid gel strength, and preventing the formation of fluid from channeling. But greater pulse pressure may cause lost circulation and even formation fracturing. Therefore, in order to ensure smooth cementing during SSFVC, the effect of pulse pressure should be considered when cementing design.

Local injection of methylprednisolonacetat to prevent seroma formation after mastectomy.

PubMed

Axelsson, Christen Kirk; Quamme, Gro Maria; Lanng, Charlotte; Szecsi, Pal Bela; Mortensen, Minea Brusgaard; Wegeberg, Birgitte; Arpi, Magnus; Lingskov, Marianne; Puglich, Mette Stub; Okholm, Mette

2012-09-01

This study served the following three purposes: To evaluate the prophylactic effect against seroma of a single dose of steroid in the mastectomy cavity, to evaluate the thesis that there is a connection between subclinical bacterial colonization and seroma formation and to evaluate if a simple urine stix test can detect postmastectomy infection. This was a double-blinded and randomized study of injection of methylprednisolonacetate versus saline in the mastectomy cavity at the time of drain removal. A total of 160 females were enrolled after mastectomy. The study parameters were as follows: seroma volume, number of seroma punctures, frequency of clinical infections, degree and type of subclinical colonization, complications and evaluation of the microbiological results of the stix test with automatically read glucose, ketones, blood, pH, protein, nitrite and leucocytes. The degree of inflammation was monitored by measurement of 15 cytokines in each sample of seroma fluid. The study was initiated in August 2010 and is expected to run for three years. Some reports have concluded that seroma formation forms part of postsurgical inflammation. Steroids are effective against inflammation and accumulation of fluid at the surgical site after several types of surgery and have also proved valuable in the treatment of seroma formation. In the present study, the prophylactic effect of steroids on seroma formation is investigated. As the incidence of postmastectomy seroma formation is 80%, there is a need for improvement in the prophylaxis and treatment of this condition. not relevant. Medicines Agency The EudraCT number 2009-016650-40 has been issued for your Sponsor's Protocol Code Number 23837. Data protection agency J.no. F.750.75-2. The study is perfomed in collaboration with the GCP Unit, capital Region, Bispebjerg Hospital under the EudraCT number: 2009-016650-40.

The increase of apatite layer formation by the poly(3-hydroxybutyrate) surface modification of hydroxyapatite and β-tricalcium phosphate.

PubMed

Szubert, M; Adamska, K; Szybowicz, M; Jesionowski, T; Buchwald, T; Voelkel, A

2014-01-01

The aim of this study was the surface modification of hydroxyapatite and β-tricalcium phosphate by poly(3-hydroxybutyrate) grafting and characterization of modificates. The bioactivity examination was carried out by the determination to grow an apatite layer on modified materials during incubation in simulated body fluid at 37°C. The additional issue taken up in this paper was to investigate the influence of fluid replacement. The process of the surface modification of biomaterials was evaluated by means of infrared and Raman spectroscopy. Formation of the apatite layer was assessed by means of scanning electron microscopy and confirmed by energy dispersive, Raman and Fourier transformed infrared spectroscopy. During exposure in simulated body fluid, the variation of the zeta potential, pH measurement and relative weight was monitored. Examination of scanning electron microscopy micrographs suggests that modification of hydroxyapatite and β-tricalcium phosphate by poly(3-hydroxybutyrate) significantly increases apatite layer formation. Raman spectroscopy evaluation revealed that the formation of the apatite layer was more significant in the case of hydroxyapatite modificate, when compared to the β-tricalcium phosphate modificate. Both modificates were characterized by stable pH, close to the natural pH of human body fluids. Furthermore, we have shown that a weekly changed, simulated body fluid solution increases apatite layer formation. © 2013.

Characterizing Droplet Formation from Non-Linear Slosh in a Propellant Tank

NASA Technical Reports Server (NTRS)

Brodnick, Jacob; Yang, Hong; West, Jeffrey

2015-01-01

The Fluid Dynamics Branch (ER42) at the Marshall Space Flight Center (MSFC) was tasked with characterizing the formation and evolution of liquid droplets resulting from nonlinear propellant slosh in a storage tank. Lateral excitation of propellant tanks can produce high amplitude nonlinear slosh waves through large amplitude excitations and or excitation frequencies near a resonance frequency of the tank. The high amplitude slosh waves become breaking waves upon attaining a certain amplitude or encountering a contracting geometry such as the upper dome section of a spherical tank. Inherent perturbations in the thinning regions of breaking waves result in alternating regions of high and low pressure within the fluid. Droplets form once the force from the local pressure differential becomes larger than the force maintaining the fluid interface shape due to surface tension. Droplets released from breaking waves in a pressurized tank may lead to ullage collapse given the appropriate conditions due to the increased liquid surface area and thus heat transfer between the fluids. The goal of this project is to create an engineering model that describes droplet formation as a function of propellant slosh for use in the evaluation of ullage collapse during a sloshing event. The Volume of Fluid (VOF) model in the production level Computational Fluid Dynamics (CFD) code Loci-Stream was used to predict droplet formation from breaking waves with realistic surface tension characteristics. Various excitation frequencies and amplitudes were investigated at multiple fill levels for a single storage tank to create the engineering model of droplet formation from lateral propellant slosh.

Mechanical Expansion of Steel Tubing as a Solution to Leaky Wellbores

PubMed Central

Radonjic, Mileva; Kupresan, Darko

2014-01-01

Wellbore cement, a procedural component of wellbore completion operations, primarily provides zonal isolation and mechanical support of the metal pipe (casing), and protects metal components from corrosive fluids. These are essential for uncompromised wellbore integrity. Cements can undergo multiple forms of failure, such as debonding at the cement/rock and cement/metal interfaces, fracturing, and defects within the cement matrix. Failures and defects within the cement will ultimately lead to fluid migration, resulting in inter-zonal fluid migration and premature well abandonment. Currently, there are over 1.8 million operating wells worldwide and over one third of these wells have leak related problems defined as Sustained Casing Pressure (SCP)1. The focus of this research was to develop an experimental setup at bench-scale to explore the effect of mechanical manipulation of wellbore casing-cement composite samples as a potential technology for the remediation of gas leaks. The experimental methodology utilized in this study enabled formation of an impermeable seal at the pipe/cement interface in a simulated wellbore system. Successful nitrogen gas flow-through measurements demonstrated that an existing microannulus was sealed at laboratory experimental conditions and fluid flow prevented by mechanical manipulation of the metal/cement composite sample. Furthermore, this methodology can be applied not only for the remediation of leaky wellbores, but also in plugging and abandonment procedures as well as wellbore completions technology, and potentially preventing negative impacts of wellbores on subsurface and surface environments. PMID:25490436

Mechanical expansion of steel tubing as a solution to leaky wellbores.

PubMed

Radonjic, Mileva; Kupresan, Darko

2014-11-20

Wellbore cement, a procedural component of wellbore completion operations, primarily provides zonal isolation and mechanical support of the metal pipe (casing), and protects metal components from corrosive fluids. These are essential for uncompromised wellbore integrity. Cements can undergo multiple forms of failure, such as debonding at the cement/rock and cement/metal interfaces, fracturing, and defects within the cement matrix. Failures and defects within the cement will ultimately lead to fluid migration, resulting in inter-zonal fluid migration and premature well abandonment. Currently, there are over 1.8 million operating wells worldwide and over one third of these wells have leak related problems defined as Sustained Casing Pressure (SCP). The focus of this research was to develop an experimental setup at bench-scale to explore the effect of mechanical manipulation of wellbore casing-cement composite samples as a potential technology for the remediation of gas leaks. The experimental methodology utilized in this study enabled formation of an impermeable seal at the pipe/cement interface in a simulated wellbore system. Successful nitrogen gas flow-through measurements demonstrated that an existing microannulus was sealed at laboratory experimental conditions and fluid flow prevented by mechanical manipulation of the metal/cement composite sample. Furthermore, this methodology can be applied not only for the remediation of leaky wellbores, but also in plugging and abandonment procedures as well as wellbore completions technology, and potentially preventing negative impacts of wellbores on subsurface and surface environments.

In situ recovery from residually heated sections in a hydrocarbon containing formation

DOEpatents

Vinegar, Harold J.; Karanikas, John Michael; Ryan, Robert Charles

2010-12-14

Methods of treating a tar sands formation is described herein. The methods may include providing heat to a first section of a hydrocarbon layer in the formation from a plurality of heaters located in the first section of the formation. Heat is transferred from the heaters so that at least a first section of the formation reaches a selected temperature. At least a portion of residual heat from the first section transfers from the first section to a second section of the formation. At least a portion of hydrocarbons in the second section are mobilized by providing a solvation fluid and/or a pressurizing fluid to the second section of the formation.

BORE II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bore II, co-developed by Berkeley Lab researchers Frank Hale, Chin-Fu Tsang, and Christine Doughty, provides vital information for solving water quality and supply problems and for improving remediation of contaminated sites. Termed "hydrophysical logging," this technology is based on the concept of measuring repeated depth profiles of fluid electric conductivity in a borehole that is pumping. As fluid enters the wellbore, its distinct electric conductivity causes peaks in the conductivity log that grow and migrate upward with time. Analysis of the evolution of the peaks enables characterization of groundwater flow distribution more quickly, more cost effectively, and with higher resolutionmore » than ever before. Combining the unique interpretation software Bore II with advanced downhole instrumentation (the hydrophysical logging tool), the method quantifies inflow and outflow locations, their associated flow rates, and the basic water quality parameters of the associated formation waters (e.g., pH, oxidation-reduction potential, temperature). In addition, when applied in conjunction with downhole fluid sampling, Bore II makes possible a complete assessment of contaminant concentration within groundwater.« less

Formation of the world's largest REE deposit through protracted fluxing of carbonatite by subduction-derived fluids

PubMed Central

Ling, Ming-Xing; Liu, Yu-Long; Williams, Ian S.; Teng, Fang-Zhen; Yang, Xiao-Yong; Ding, Xing; Wei, Gang-Jian; Xie, Lu-Hua; Deng, Wen-Feng; Sun, Wei-Dong

2013-01-01

Rare Earth Elements (REE) are essential to modern society but the origins of many large REE deposits remain unclear. The U-Th-Pb ages, chemical compositions and C, O and Mg isotopic compositions of Bayan Obo, the world's largest REE deposit, indicate a protracted mineralisation history with unusual chemical and isotopic features. Coexisting calcite and dolomite are in O isotope disequilibrium; some calcitic carbonatite samples show highly varied δ26Mg which increases with increasing Si and Mg; and ankerite crystals show decreases in Fe and REE from rim to centre, with highly varied REE patterns. These and many other observations are consistent with an unusual mineralisation process not previously considered; protracted fluxing of calcitic carbonatite by subduction-released high-Si fluids during the closure of the Palaeo-Asian Ocean. The fluids leached Fe and Mg from the mantle wedge and scavenged REE, Nb and Th from carbonatite, forming the deposit through metasomatism of overlying sedimentary carbonate.

Study of a magnetorheological fluid submitted to a uniform magnetic field

NASA Astrophysics Data System (ADS)

Fonseca, H. A.; Gonzalez, E.; Restrepo, J.

2017-12-01

In this work, the rheological and hyperfine properties of a magnetorheological fluid (MRF) under the action of a uniform external magnetic field are analysed. Powders of native mineral magnetite of micrometric particle size, after a pulverization process, form the solute of these fluids. The sizes of these samples are selected by sieving in order to obtain sizes of around 20µm and 45µm. The powders are characterized by means of Mössbauer spectroscopy to analyse their stoichiometry giving rise to a non-stoichiometric magnetite Fe2.96O4 in addition to a hematite component. Result of viscosity and shear stress in the low-speed regime were analysed using the Hershel Buckley method. In particular, the case of surface tension it decreases with the application of a uniform magnetic flux density, which is understood in terms of a phase separation due to the formation of mesoscopic structures, thus decreasing the cohesion force and increasing the adhesion force.

In situ heat treatment of a tar sands formation after drive process treatment

DOEpatents

Vinegar, Harold J.; Stanecki, John

2010-09-21

A method for treating a tar sands formation includes providing a drive fluid to a hydrocarbon containing layer of the tar sands formation to mobilize at least some hydrocarbons in the layer. At least some first hydrocarbons from the layer are produced. Heat is provided to the layer from one or more heaters located in the formation. At least some second hydrocarbons are produced from the layer of the formation. The second hydrocarbons include at least some hydrocarbons that are upgraded compared to the first hydrocarbons produced by using the drive fluid.

Influence of Applied Voltage and Film-Formation Time on Microstructure and Corrosion Resistance of Coatings Formed on Mg-Zn-Zr-Ca Bio-magnesium Alloy

NASA Astrophysics Data System (ADS)

Yandong, Yu; Shuzhen, Kuang; Jie, Li

2015-09-01

The influence of applied voltage and film-formation time on the microstructure and corrosion resistance of coatings formed on a Mg-Zn-Zr-Ca novel bio-magnesium alloy has been investigated by micro-arc oxidation (MAO) treatment. Phase composition and microstructure of as-coated samples were analyzed by the x-ray diffraction, energy dispersive x-ray spectroscopy and scanning electron microscopy. And the porosity and average of micro-pore aperture of the surface on ceramic coatings were analyzed by general image software. Corrosion microstructure of as-coated samples was caught by a microscope digital camera. The long-term corrosion resistance of as-coated samples was tested in simulated body fluid for 30 days. The results showed that the milky white smooth ceramic coating formed on the Mg-Zn-Zr-Ca novel bio-magnesium alloy was a compound of MgO, Mg2SiO4 and MgSiO3, and its corrosion resistance was significantly improved compared with that of the magnesium substrate. In addition, when the MAO applied voltage were 450 V and 500 V and film-formation time were 9 min and 11 min, the surface micro-morphology and the corrosion resistance of as-coated samples were relatively improved. The results provided a theoretical foundation for the application of the Mg-Zn-Zr-Ca novel bio-magnesium alloy in biomedicine.

Reaction path modelling of in-situ mineralisation of CO2 at the CarbFix site at Hellisheidi, SW-Iceland

NASA Astrophysics Data System (ADS)

Snæbjörnsdóttir, Sandra Ó.; Gislason, Sigurdur R.; Galeczka, Iwona M.; Oelkers, Eric H.

2018-01-01

Results from injection of 175 tonnes of CO2 into the basaltic subsurface rocks at the CarbFix site in SW-Iceland in 2012 show almost complete mineralisation of the injected carbon in less than two years (Matter et al., 2016; Snæbjörnsdóttir et al., 2017). Reaction path modelling was performed to illuminate the rate and extent of CO2-water-rock reactions during and after the injection. The modelling calculations were constrained by the compositions of fluids sampled prior to, during, and after the injection, as reported by Alfredsson et al. (2013) and Snæbjörnsdóttir et al. (2017). The pH of the injected fluid, prior to CO2 dissolution was ∼9.5, whereas the pH of the background waters in the first monitoring well prior to the injections was ∼9.4. The pH of the sampled fluids used in the modelling ranged from ∼3.7 at the injection well to as high as 8.2 in the first monitoring well. Modelling results suggest that CO2-rich water-basalt interaction is dominated by crystalline basalt dissolution along a faster, high permeability flow path, but by basaltic glass dissolution along a slower, pervasive flow path through which the bulk of the injected fluid flows. Dissolution of pre-existing calcite at the onset of the injection does not have a net effect on the carbonation, but does contribute to a rapid early pH rise during the injection, and influences which carbonate minerals precipitate. At low pH, Mg, and Fe are preferentially released from crystalline basalts due to the higher dissolution rates of olivine, and to lesser extent pyroxene, compared to plagioclase and glass (Gudbrandsson et al., 2011). This favours the formation of siderite and Fe-Mg carbonates over calcite during early mineralisation. The model suggests the formation of the following carbonate mineral sequences: siderite at pH < 5, Mg-Fe-carbonates and Ca-Mg-Fe-carbonates at pH > 5, and calcite at higher pH. Other minerals forming with the carbonates are Al- and Fe-hydroxides and chalcedony, and zeolites and smectites at elevated pH. The most efficient carbonate formation is when the pH is high enough for formation of carbonates, but not so high that zeolites and smectites start to form, which compete with carbonates over both cations and pore space. The results of reaction path modelling at the CarbFix site in SW-Iceland indicate that this ;sweet spot; for mineralisation of CO2 is at pH from ∼5.2 to 6.5 in basalts at low temperature (20-50 °C).

Evaluation of Cavitation Erosion Behavior of Commercial Steel Grades Used in the Design of Fluid Machinery

NASA Astrophysics Data System (ADS)

Tzanakis, I.; Bolzoni, L.; Eskin, D. G.; Hadfield, M.

2017-05-01

The erosion response under cavitation of different steel grades was assessed by studying the erosion rate, the volume removal, the roughness evolution, and the accumulated strain energy. A 20 kHz ultrasonic transducer with a probe diameter of 5 mm and peak-to-peak amplitude of 50 μm was deployed in distilled water to induce damage on the surface of commercial chromium and carbon steel samples. After a relatively short incubation period, cavitation induced the formation of pits, cracks, and craters whose features strongly depended on the hardness and composition of the tested steel. AISI 52100 chromium steel showed the best performance and is, therefore, a promising design candidate for replacing the existing fluid machinery materials that operate within potential cavitating environments.

30 CFR 250.490 - Hydrogen sulfide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... where neither the presence nor absence of H2S has been confirmed. Well-control fluid means drilling mud..., well logs, formation tests, cores and analysis of formation fluids; and (4) Submit a request for... initiate when the SO2 concentration in the atmosphere reaches 5 ppm; (20) Engineering controls to protect...

Natural Tracers and Multi-Scale Assessment of Caprock Sealing Behavior: A Case Study of the Kirtland Formation, San Juan Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jason Heath; Brian McPherson; Thomas Dewers

The assessment of caprocks for geologic CO{sub 2} storage is a multi-scale endeavor. Investigation of a regional caprock - the Kirtland Formation, San Juan Basin, USA - at the pore-network scale indicates high capillary sealing capacity and low permeabilities. Core and wellscale data, however, indicate a potential seal bypass system as evidenced by multiple mineralized fractures and methane gas saturations within the caprock. Our interpretation of {sup 4}He concentrations, measured at the top and bottom of the caprock, suggests low fluid fluxes through the caprock: (1) Of the total {sup 4}He produced in situ (i.e., at the locations of sampling)more » by uranium and thorium decay since deposition of the Kirtland Formation, a large portion still resides in the pore fluids. (2) Simple advection-only and advection-diffusion models, using the measured {sup 4}He concentrations, indicate low permeability ({approx}10-20 m{sup 2} or lower) for the thickness of the Kirtland Formation. These findings, however, do not guarantee the lack of a large-scale bypass system. The measured data, located near the boundary conditions of the models (i.e., the overlying and underlying aquifers), limit our testing of conceptual models and the sensitivity of model parameterization. Thus, we suggest approaches for future studies to better assess the presence or lack of a seal bypass system at this particular site and for other sites in general.« less

Renal-Stone Risk Assessment During Space Shuttle Flights

NASA Technical Reports Server (NTRS)

Whitson, Peggy A.; Pietrzyk, Robert A.; Pak, Charles Y. C.

1996-01-01

The metabolic and environmental factors influencing renal stone formation before, during, and after Space Shuttle flights were assessed. We established the contributing roles of dietary factors in relationship to the urinary risk factors associated with renal stone formation. 24-hr urine samples were collected prior to, during space flight, and following landing. Urinary factors associated with renal stone formation were analyzed and the relative urinary supersaturation ratios of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were calculated. Food and fluid consumption was recorded for a 48-hr period ending with the urine collection. Urinary composition changed during flight to favor the crystallization of stone-forming salts. Factors that contributed to increased potential for stone formation during space flight were significant reductions in urinary pH and increases in urinary calcium. Urinary output and citrate, a potent inhibitor of calcium-containing stones, were slightly reduced during space flight. Dietary intakes were significantly reduced for a number of variables, including fluid, energy, protein, potassium, phosphorus and magnesium. This is the first in-flight characterization of the renal stone forming potential in astronauts. With the examination of urinary components and nutritional factors, it was possible to determine the factors that contributed to increased risk or protected from risk. In spite of the protective components, the negative contributions to renal stone risk predominated and resulted in a urinary environment that favored the supersaturation of stone-forming salts. The importance of the hypercalciuria was noted since renal excretion was high relative to the intake.

San Andreas fault zone drilling project: scientific objectives and technological challenges

USGS Publications Warehouse

Hickman, S.H.; Younker, L.W.; Zoback, M.D.

1995-01-01

We are leading a new international initiative to conduct scientific drilling within the San Andreas fault zone at depths of up to 10 km. This project is motivated by the need to understand the physical and chemical processes operating within the fault zone and to answer fundamental questions about earthquake generation along major plate-boundary faults. Through a comprehensive program of coring, fluid sampling, downhole measurements, laboratory experimentation, and long-term monitoring, we hope to obtain critical information on the structure, composition, mechanical behavior and physical state of the San Andreas fault system at depths comparable to the nucleation zones of great earthquakes. The drilling, sampling and observational requirements needed to ensure the success of this project are stringent. These include: 1) drilling stable vertical holes to depths of about 9 km in fractured rock at temperatures of up to 300°C; 2) continuous coring and completion of inclined holes branched off these vertical boreholes to intersect the fault at depths of 3, 6, and 9 km; 3) conducting sophisticated borehole geophysical measurements and fluid/rock sampling at high temperatures and pressures; and 4) instrumenting some or all of these inclined core holes for continuous monitoring of earthquake activity, fluid pressure, deformation and other parameters for periods of up to several decades. For all of these tasks, because of the overpressured clay-rich formations anticipated within the fault zone at depth, we expect to encounter difficult drilling, coring and hole-completion conditions in the region of greatest scientific interest.

Localized fluid discharge in subduction zones: Insights from tension veins around an ancient megasplay fault (Nobeoka Thrust, SW Japan)

NASA Astrophysics Data System (ADS)

Otsubo, M.; Hardebeck, J.; Miyakawa, A.; Yamaguchi, A.; Kimura, G.

2017-12-01

Fluid-rock interactions along seismogenic faults are of great importance to understand fault mechanics. The fluid loss by the formation of mode I cracks (tension cracks) increases the fault strength and creates drainage asperities along the plate interface (Sibson, 2013, Tectonophysics). The Nobeoka Thrust, in southwestern Japan, is an on-land example of an ancient megasplay fault and provides an excellent record of deformation and fluid flow at seismogenic depths of a subduction zone (Kondo et al., 2005, Tectonics). We focus on (1) Pore fluid pressure loss, (2) Amount of fault strength recovery, and (3) Fluid circulation by the formation of mode I cracks in the post-seismic period around the fault zone of the Nobeoka Thrust. Many quartz veins that filled mode I crack at the coastal outcrops suggest a normal faulting stress regime after faulting of the Nobeoka Thrust (Otsubo et al., 2016, Island Arc). We estimated the decrease of the pore fluid pressure by the formation of the mode I cracks around the Nobeoka Thrust in the post-seismic period. When the pore fluid pressure exceeds σ3, veins filling mode I cracks are constructed (Jolly and Sanderson, 1997, Jour. Struct. Geol.). We call the pore fluid pressure that exceeds σ3 "pore fluid over pressure". The differential stress in the post-seismic period and the driving pore fluid pressure ratio P* (P* = (Pf - σ3) / (σ1 - σ3), Pf: pore fluid pressure) are parameters to estimate the pore fluid over pressure. In the case of the Nobeoka Thrust (P* = 0.4, Otsubo et al., 2016, Island Arc), the pore fluid over pressure is up to 20 MPa (assuming tensile strength = 10 MPa). 20 MPa is equivalent to <10% of the total pore fluid pressure around the Nobeoka Thrust (depth = 10 km, density = 2.7 kg/m3). When the pore fluid pressure decreases by 4%, the normalized pore pressure ratio λ* (λ* = (Pf - Ph) / (Pl - Ph), Pl: lithostatic pressure; Ph: hydrostatic pressure) changes from 0.95 to 0.86. In the case of the Nobeoka Thrust, the fault strength can increase by up to 10 MPa (assuming frictional coefficient = 0.6). 10 MPa is almost equivalent to the stress drop values in large trench type earthquakes. Hence, we suggest that the fluid loss caused by the formation of mode I cracks in the post-seismic period may play an important role by increasing frictional strength along the megasplay fault.

Modern Processes of Hydrocarbon Migration and Re-Formation of Oil and Gas Fields (Based on the Results of Monitoring and Geochemical Studies)

NASA Astrophysics Data System (ADS)

Plotnikova, Irina; Salakhidinova, Gulmira; Nosova, Fidania; Pronin, Nikita; Ostroukhov, Sergey

2015-04-01

Special geochemical studies of oils allowed to allocate a movable migration component of oils in the industrial oil deposits. In the field the migration component of oils varies in different parts of the field. The largest percentage of the light migration component (gas condensate of the oil) was detected in the central part of the Kama-Kinel troughs system. Monitoring of the composition of water, oil and gas (condensate light oil component) in the sedimentary cover and ni crystalline basement led to the conclusion of modern migration of hydrocarbons in sedimentary cover. This proves the existence of the modern processes of formation and reformation of oil and gas fields. This presentation is dedicated to the problem of definition of geochemical criteria of selection of hydrocarbons deposit reformation zone in the sample wells of Minibaevskaya area of Romashkinskoye field. While carrying out this work we examined 11 samples of oil from the Upper Devonian Pashiysky horizon. Four oil samples were collected from wells reckoned among the "anomalous" zones that were marked out according to the results of geophysical, oil field and geological research. Geochemical studies of oils were conducted in the laboratory of geochemistry of the Kazan (Volga-region) Federal University. The wells where the signs of hydrocarbons influx from the deep zones of the crust were recorded are considered to be "anomalous". A number of scientists connect this fact to the hypothesis about periodic influx of deep hydrocarbons to the oil deposits of Romashkinskoye field. Other researchers believe that the source rocks of the adjacent valleys sedimentary cover generate gases when entering the main zone of gas formation, which then migrate up the section and passing through the previously formed deposits of oil, change and "lighten" their composition. Regardless of the point of view on the source of the hydrocarbons, the study of the process of deposits refilling with light hydrocarbons is an important fundamental task of exceptional practical importance. The reservoir water monitoring has been conducted in five wells that have penetrated the water-saturated, loosely aggregated zones of the South Tatarstan Arch's basement. The long-term testing resulted in the production of reservoir water from the basement. The sedimentary cover in these wells is blocked by the column, which prevents water cross-flowing from the sedimentary cover. The observations have shown that the levels, gas saturation, mineralisation, density, and composition of reservoir waters from the loosely aggregated zones of the basement change with time. The varying characteristics of the water include its component composition, redox potential, and amount of chlorine and some other components and trace elements. Compositional changes in gases of the loosely aggregated zones of the basement, variations in the gas saturation of reservoir waters and of their composition, the decreasing density of oil in the sedimentary cover, - all result from one cause. This cause is the movement of fluids (solutions and gases dissolved in them) through the loosely aggregated zones and faults of the Earth's crust and the sedimentary cover. The fluids mainly move vertically in an upward direction, although their migration through subhorizontal, loosely aggregated zones of the crystalline basement is also possible. Fluid migration still takes place in the Earth's crust of ancient platforms. This phenomenon indicates that some portions of the platforms - primarily, their margins - periodically resume tectonic activities. The fluid dynamic activity of the crust define the processes in the sedimentary cover. It affects the development of the sedimentary basin during the sedimentation period, and the formation of mineral deposits. The monitoring of the present-day movement of fluid systems in the loosely aggregated zones of the basement will permit the more detailed study of the present-day fluid regime in the upper portion of the Earth's crust and the sedimentary cover.

Hydraulic Properties of Fractured Rock Samples at In-Situ Conditions - Insights from Lab Experiments Using X-Ray Tomography

NASA Astrophysics Data System (ADS)

Nehler, Mathias; Stöckhert, Ferdinand; Duda, Mandy; Renner, Jörg; Bracke, Rolf

2017-04-01

The hydraulic properties of low-porosity rock formations are controlled by the geometry of open fractures, joints and faults. Aperture, surface roughness, accessible length, and thus, the volume available for fluids associated of such interfaces are strongly affected by their state of stress. Moreover, these properties may evolve with time in particular due to processes involving chemically active fluids. Understanding the physico-chemical interactions of rocks with fluids at reservoir conditions will help to predict the long-term reservoir development and to increase the efficiency of geothermal power plants. We designed an x-ray transparent flow-through cell. Confining pressure can be up to 50 MPa and pore fluid can currently be circulated through the sample with pressures of up to 25 MPa. All wetted parts are made of PEEK to avoid corrosion when using highly saline fluids. Laboratory experiments were performed to investigate hydraulic properties of fractured low-porosity samples under reservoir conditions while x-rays transmit the sample. The cell is placed inside a µCT scanner with a 225 kV multifocal x-ray tube for high resolution x-ray tomography. Samples measure 10 mm in diameter and 25 mm in length resulting in a voxel resolution of approximately 10 µm. Samples with single natural as well as artificial fractures were subjected to various confining pressures ranging from 2.5 MPa to 25 MPa. At each pressure level, effective permeability was determined from steady-state flow relying on Darcy's law. In addition, a full 3D image was recorded by the µCT scanner to gain information on the fracture aperture and geometry. Subvolumes (400x400x400 voxels) of the images were analyzed to reduce computational cost. The subvolumes were filtered in 3D with an edge preserving non-local means filter. Further quantification algorithms were implemented in Matlab. Segmentation into pore space and minerals was done automatically for all datasets by a peak finder algorithm. For all samples, the threshold value was set as a fixed value between the two determined main peaks. A fracture is separated from pores using a connectivity filter. The overall porosity and the fracture volume are calculated. The mean aperture is used to calculate the in-situ fracture permeability according to the cubic law. First results indicate a strong dependency of the calculated permeability on pressure, especially for partly closed fractures, that is associated with an increasing contact area of the fracture.

Regional fluid and metal mobility in the Dalradian metamorphic belt, Southern Grampian Highlands, Scotland

NASA Astrophysics Data System (ADS)

Craw, D.

1990-10-01

A prominent set of veins was formed during post-metamorphic deformation of the Caledonian Dalradian metamorphic belt. These veins are concentrated in dilational zones in fold hinges, but apophyses follow schistosity and fold axial surface fractures. The veins are most common in the cores of regional structures, especially the Dalradian Downbend and consist of quartz, calcite, chlorite and metallic sulphides and oxides. Metals, including gold, have been concentrated in the veins. The fluid which formed the veins was low salinity (1 5 wt% NaCl and KCl) CO2-bearing (3 16 wt% CO2) water of metamorphic origin. The fluid varies slightly in composition within and between samples, but is essentially uniform in composition over several hundred km2. Vein formation occurred at about 350±50 °C and 200 300 MPa pressure. Further quartz mineralization occurred in some dilational zones at lower temperatures (160 180 °C). This later mineralization was accompanied by CO2 immiscibility. Dilution and oxidation of the metamorphic fluid occurred due to mixing with meteoric water as the rocks passed through the brittle-ductile transition. A similar metamorphic fluid is thought to have been responsible for gold mineralization in the nearby Tyndrum Fault at a later stage in the Dalradian uplift.

Palaeomagnetic dating of widespread remagnetization on the southeastern border of the French Massif Central and implications for fluid and Mississippi Valley-type mineralization

USGS Publications Warehouse

Henry, B.; Rouvier, H.; Goff, M.L.; Leach, D.; Macquar, J.-C.; Thibieroz, J.; Lewchuk, Michael T.

2001-01-01

Palaeomagnetic dating techniques have been applied to determine the age of fluid migration that produced the Mississippi Valley-type (MVT) Pb-Zn-Ba-F deposits in the Ce??vennes region of southern France. 15 sampling sites in two gently deformed areas around the Largentie??re and Croix-de-Pallie??res mines on the Ce??vennes border were selected for palaeomagnetic study. They yielded a very well-defined direction of remagnetization corresponding to an Early-Middle Eocene age. This remagnetization cannot be related to the formation of magnetic as a result of the transformation of smectite to illite because the latter has been well dated as a Mesozoic event. The magnetic overprint in this area is related to a chemical phenomenon during fluid migration. The age of remagnetization corresponds to a major uplift in the Pyre??ne??es mountains, located to the south of the Ce??vennes. This implies that fluid migration occurred from the south to the north as a result of hydraulic head established in the Pyre??ne??es orogenic belt during orogenesis and suggests that the MVT deposits in the Ce??vennes region formed from a gravity-driven fluid system as described by Garven & Freeze (1984a,b).

Accelerated gravity testing of aquitard core permeability and implications at formation and regional scale

NASA Astrophysics Data System (ADS)

Timms, W. A.; Crane, R.; Anderson, D. J.; Bouzalakos, S.; Whelan, M.; McGeeney, D.; Rahman, P. F.; Guinea, A.; Acworth, R. I.

2015-03-01

Evaluating the possibility of leakage through low permeability geological strata is critically important for sustainable water supplies, the extraction of fuels from strata such as coal beds, and the confinement of waste within the earth. The current work demonstrates that relatively rapid and reliable hydraulic conductivity (K) measurement of aquitard cores using accelerated gravity can inform and constrain larger scale assessments of hydraulic connectivity. Steady state fluid velocity through a low K porous sample is linearly related to accelerated gravity (g-level) in a centrifuge permeameter (CP) unless consolidation or geochemical reactions occur. The CP module was custom designed to fit a standard 2 m diameter geotechnical centrifuge (550 g maximum) with a capacity for sample dimensions of 30 to 100 mm diameter and 30 to 200 mm in length, and a maximum total stress of ~2 MPa at the base of the core. Formation fluids were used as influent to limit any shrink-swell phenomena which may alter the permeability. Vertical hydraulic conductivity (Kv) results from CP testing of cores from three sites within the same regional clayey silt formation varied (10-7 to 10-9 m s-1, n = 14). Results at one of these sites (1.1 × 10-10 to 3.5 × 10-9 m s-1, n = 5) that were obtained in < 24 h were similar to in situ Kv values (3 × 10-9 m s-1) from pore pressure responses over several weeks within a 30 m clayey sequence. Core scale and in situ Kv results were compared with vertical connectivity within a regional flow model, and considered in the context of heterogeneity and preferential flow paths at site and formation scale. More reliable assessments of leakage and solute transport though aquitards over multi-decadal timescales can be achieved by accelerated core testing together with advanced geostatistical and numerical methods.

Authigenic carbonate formation at hydrocarbon seeps in continental margin sediments: A comparative study

USGS Publications Warehouse

Naehr, T.H.; Eichhubl, P.; Orphan, V.J.; Hovland, M.; Paull, C.K.; Ussler, W.; Lorenson, T.D.; Greene, H. Gary

2007-01-01

Authigenic carbonates from five continental margin locations, the Eel River Basin, Monterey Bay, Santa Barbara Basin, the Sea of Okhotsk, and the North Sea, exhibit a wide range of mineralogical and stable isotopic compositions. These precipitates include aragonite, low- and high-Mg calcite, and dolomite. The carbon isotopic composition of carbonates varies widely, ranging from -60??? to +26???, indicating complex carbon sources that include 13C-depleted microbial and thermogenic methane and residual, 13C-enriched, bicarbonate. A similarly large variability of ??18O values (-5.5??? to +8.9???) demonstrates the geochemical complexity of these sites, with some samples pointing toward an 18O-enriched oxygen source possibly related to advection of 18O-enriched formation water or to the decomposition of gas hydrate. Samples depleted in 18O are consistent with formation deeper in the sediment or mixing of pore fluids with meteoric water during carbonate precipitation. A wide range of isotopic and mineralogical variation in authigenic carbonate composition within individual study areas but common trends across multiple geographic areas suggest that these parameters alone are not indicative for certain tectonic or geochemical settings. Rather, the observed variations probably reflect local controls on the flux of carbon and other reduced ions, such as faults, fluid conduits, the presence or absence of gas hydrate in the sediment, and the temporal evolution of the local carbon reservoir. Areas with seafloor carbonates that indicate formation at greater depth below the sediment-water interface must have undergone uplift and erosion in the past or are still being uplifted. Consequently, the occurrence of carbonate slabs on the seafloor in areas of active hydrocarbon seepage is commonly an indicator of exhumation following carbonate precipitation in the shallow subsurface. Therefore, careful petrographic and geochemical analyses are critical components necessary for the correct interpretation of processes related to hydrocarbon seepage in continental margin environments and elsewhere. ?? 2007 Elsevier Ltd. All rights reserved.

Regularities of changes in fluid composition and properties in Vankor field pools: from light to heavy oil

NASA Astrophysics Data System (ADS)

Goncharov, I. V.; Oblasov, N. V.

2015-02-01

Oil in layers Nkh 3-4, Nkh 1, Sd 9, Yak 3-7 and vYak 2-4 of the Vankor field occurs at the depth of -2,767 to -1,357 meters at strongly different temperatures: from 62 to 26 °C. Such temperature conditions contribute to oil biodegradation processes in the pool. Therefore, oils in different pools significantly differ from each other in terms of composition and properties depending on the intensity of biodegradation. At the same time, pools might embrace both oils that have practically been not exposed to biodegradation processes and significantly biodegraded oils. The most seriously altered oils are found in vYak 2-4 layer pools. They are the heaviest and the most viscous oils among the samples under study. Many typical oil components (alkanes, alkylbenzenes, naphthalenes, phenanthrenes, dibenzothiophenes) are absent in their composition. Besides, the initial distribution of hopanes in the composition of biomarkers is altered. Apart from the molecular composition of degassed oil samples, the work also studies the effect of biodegradation on the properties and the component and isotopic composition of oils, gases and formation fluid samples.

Volcanism and massive sulfide formation at a sedimented spreading center, Escanaba Trough, Gorda Ridge, northeast Pacific.

USGS Publications Warehouse

Morton, J.L.; Holmes, M.L.; Koski, R.A.

1987-01-01

Seismic-reflection profiles over the sediment-filled Escanaba Trough at the southern Gorda Ridge reveal a series of volcanic centers that pierce the sediment. The volcanic edifices are 3 to 6 km in diameter and are spaced at 15 to 20 km intervals along the axis of the trough. Composition and form of sulfide samples obtained from the bank suggest significant interaction between hydrothermal fluids and sediment at depth, and deposition of sulfide within the sediment pile.-from Authors

Optimal probes for withdrawal of uncontaminated fluid samples

NASA Astrophysics Data System (ADS)

Sherwood, J. D.

2005-08-01

Withdrawal of fluid by a composite probe pushed against the face z =0 of a porous half-space z >0 is modeled assuming incompressible Darcy flow. The probe is circular, of radius a, with an inner sampling section of radius αa and a concentric outer guard probe αa βa is saturated with fluid 2; the two fluids have the same viscosity. It is assumed that the interface between the two fluids is sharp and remains so as it moves through the rock. The pressure in the probe is lower than that of the pore fluid in the rock, so that the fluid interface is convected with the fluids towards the probe. This idealized axisymmetric problem is solved numerically, and it is shown that an analysis based on far-field spherical flow towards a point sink is a good approximation when the nondimensional depth of fluid 1 is large, i.e., β ≫1. The inner sampling probe eventually produces pure fluid 2, and this technique has been proposed for sampling pore fluids in rock surrounding an oil well [A. Hrametz, C. Gardner, M. Wais, and M. Proett, U.S. Patent No. 6,301,959 B1 (16 October 2001)]. Fluid 1 is drilling fluid filtrate, which has displaced the original pore fluid (fluid 2), a pure sample of which is required. The time required to collect an uncontaminated sample of original pore fluid can be minimized by a suitable choice of the probe geometry α [J. Sherwood, J. Fitzgerald and B. Hill, U.S. Patent No. 6,719,049 B2 (13 April 2004)]. It is shown that the optimal choice of α depends on the depth of filtrate invasion β and the volume of sample required.

Transthyretin Sequesters Amyloid β Protein and Prevents Amyloid Formation

NASA Astrophysics Data System (ADS)

Schwarzman, Alexander L.; Gregori, Luisa; Vitek, Michael P.; Lyubski, Sergey; Strittmatter, Warren J.; Enghilde, Jan J.; Bhasin, Ramaninder; Silverman, Josh; Weisgraber, Karl H.; Coyle, Patricia K.; Zagorski, Michael G.; Talafous, Joseph; Eisenberg, Moises; Saunders, Ann M.; Roses, Allen D.; Goldgaber, Dmitry

1994-08-01

The cardinal pathological features of Alzheimer disease are depositions of aggregated amyloid β protein (Aβ) in the brain and cerebrovasculature. However, the Aβ is found in a soluble form in cerebrospinal fluid in healthy individuals and patients with Alzheimer disease. We postulate that sequestration of Aβ precludes amyloid formation. Failure to sequester Aβ in Alzheimer disease may result in amyloidosis. When we added Aβ to cerebrospinal fluid of patients and controls it was rapidly sequestered into stable complexes with transthyretin. Complexes with apolipoprotein E, which has been shown to bind Aβ in vitro, were not observed in cerebrospinal fluid. Additional in vitro studies showed that both purified transthyretin and apolipoprotein E prevent amyloid formation.

Aspects of wellbore heat transfer during two-phase flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasan, A.R.; Kabir, C.S.

1994-08-01

Wellbore fluid temperature is governed by the rate of heat loss from the wellbore to the surrounding formation, which in turn is a function of depth and production/injection time. The authors present an approach to estimate wellbore fluid temperature during steady-state two-phase flow. The method incorporates a new solution of the thermal diffusivity equation and the effect of both conductive and convective heat transport for the wellbore/formation system. For the multiphase flow in the wellbore, the Hasan-Kabir model has been adapted, although other mechanistic models may be used. A field example is used to illustrate the fluid temperature calculation proceduremore » and shows the importance of accounting for convection in the tubing/casing annulus. A sensitivity study shows that significant differences exist between the predicted wellhead temperature and the formation surface temperature and that the fluid temperature gradient is nonlinear. This study further shows that increased free gas lowers the wellhead temperature as a result of the Joule-Thompson effect. In such cases, the expression for fluid temperature developed earlier for single-phase flow should not be applied when multiphase flow is encountered. An appropriate expression is presented in this work for wellbores producing multiphase fluids.« less

Serious Fun: Using Toys to Demonstrate Fluid Mechanics Principles

ERIC Educational Resources Information Center

Saviz, Camilla M.; Shakerin, Said

2014-01-01

Many students have owned or seen fluids toys in which two immiscible fluids within a closed container can be tilted to generate waves. These types of inexpensive and readily available toys are fun to play with, but they are also useful for provoking student learning about fluid properties or complex fluid behavior, including drop formation and…

Glyceryl ether sulfonates for use in oil recovery fluids and processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCoy, D.R.

1984-08-21

Petroleum may be recovered from petroleum containing formations having high salinity by injecting into the formation an aqueous fluid containing an effective amount of a surface active agent characterized by the formula: R/sub 1/(OCH/sub 2/CH(OH)CH/sub 2/) /SUB m/ (R/sub 2/) /SUB n/ OR/sub 3/SO/sub 3/X wherein R/sub 1/ is an alkyl or alkylaryl radical, m is an integer of from 1 to 10, R/sub 2/ is an ethoxy radical and/or 1,2-propoxy radical, n is an integer of from 0 to 10, R/sub 3/ is an ethylene or 1,3-propylene radical, X is a sodium, potassium or ammonium cation; and driving themore » fluid through the formation and thereby displacing and recovering petroleum from the formation.« less

The laser radiation action on the crystal formation processes in the biological fluids

NASA Astrophysics Data System (ADS)

Malov, Alexander N.; Vaichas, Andrey A.; Novikova, Evgeniya A.

2016-11-01

The results of an experimental study of the laser radiation effect on the crystal`s formation in the volume of biological fluids that are complex multi-component solutions have been discussing. Are investigated white and natural bile in vitro. The qualitative changes were observed. Thus, at the bottom of the cell in which bile is not exposed to the laser radiation, the crystals are formed. In the irradiated bile gallstone has a thin layer of a homogeneous viscous colloidal liquid with very small, visible in polarized light crystalline formations was got. Irradiated laser bile's gallstone was covered evenly white deposit without surface defect unlike gallstone in bile without radiation exposure. A possible mechanism to explain the laser radiation action on the mineral formation in biological fluids and also practical application of this effect have been suggesting too.

Fast intraslab fluid-flow events linked to pulses of high pore fluid pressure at the subducted plate interface

NASA Astrophysics Data System (ADS)

Taetz, Stephan; John, Timm; Bröcker, Michael; Spandler, Carl; Stracke, Andreas

2018-01-01

A better understanding of the subduction zone fluid cycle and its chemical-mechanical feedback requires in-depth knowledge about how fluids flow within and out of descending slabs. Relicts of fluid-flow systems in exhumed rocks of fossil subduction zones allow for identification of the general relationships between dehydration reactions, fluid pathway formation, the dimensions and timescales of distinct fluid flow events; all of which are required for quantitative models for fluid-induced subduction zone processes. Two types of garnet-quartz-phengite veins can be distinguished in an eclogite-facies mélange block from the Pouébo Eclogite Mélange, New Caledonia. These veins record synmetamorphic internal fluid release by mineral breakdown reactions (type I veins), and infiltration of an external fluid (type II veins) with the associated formation of a reaction selvage. The dehydration and fluid migration documented by the type I veins likely occurred on a timescale of 105-106 years, based on average subduction rates and metamorphic conditions required for mineral dehydration and fluid flow. The timeframe of fluid-rock interaction between the external fluid and the wall-rock of the type II veins is quantified using a continuous bulk-rock Li-diffusion profile perpendicular to a vein and its metasomatic selvage. Differences in Li concentration between the internal and external fluid reservoirs resulted in a distinct diffusion profile (decreasing Li concentration and increasing δ7 Li) as the reaction front propagated into the host rock. Li-chronometric constraints indicate that the timescales of fluid-rock interaction associated with type II vein formation are on the order of 1 to 4 months (0.150-0.08+0.14 years). The short-lived, pulse-like character of this process is consistent with the notion that fluid flow caused by oceanic crust dehydration at the blueschist-to-eclogite transition contributes to or even dominates episodic pore fluid pressure increases at the plate interface, which in turn, may trigger slip events reported from many subduction zones.

Evolution of fracture permeability of ultramafic rocks undergoing serpentinization at hydrothermal conditions: An experimental study

NASA Astrophysics Data System (ADS)

Farough, A.; Moore, D. E.; Lockner, D. A.; Lowell, R. P.

2016-01-01

We performed flow-through laboratory experiments on five cylindrically cored samples of ultramafic rocks, in which we generated a well-mated through-going tensile fracture, to investigate evolution of fracture permeability during serpentinization. The samples were tested in a triaxial loading machine at a confining pressure of 50 MPa, pore pressure of 20 MPa, and temperature of 260°C, simulating a depth of 2 km under hydrostatic conditions. A pore pressure difference of up to 2 MPa was imposed across the ends of the sample. Fracture permeability decreased by 1-2 orders of magnitude during the 200-330 h experiments. Electron microprobe and SEM data indicated the formation of needle-shaped crystals of serpentine composition along the walls of the fracture, and chemical analyses of sampled pore fluids were consistent with dissolution of ferro-magnesian minerals. By comparing the difference between fracture permeability and matrix permeability measured on intact samples of the same rock types, we concluded that the contribution of the low matrix permeability to flow is negligible and essentially all of the flow is focused in the tensile fracture. The experimental results suggest that the fracture network in long-lived hydrothermal circulation systems can be sealed rapidly as a result of mineral precipitation, and generation of new permeability resulting from a combination of tectonic and crystallization-induced stresses is required to maintain fluid circulation.

Evolution of fracture permeability of ultramafic rocks undergoing serpentinization at hydrothermal conditions: An experimental study

USGS Publications Warehouse

Farough, Aida; Moore, Diane E.; Lockner, David A.; Lowell, R.P.

2016-01-01

We performed flow-through laboratory experiments on five cylindrically cored samples of ultramafic rocks, in which we generated a well-mated through-going tensile fracture, to investigate evolution of fracture permeability during serpentinization. The samples were tested in a triaxial loading machine at a confining pressure of 50 MPa, pore pressure of 20 MPa, and temperature of 260°C, simulating a depth of 2 km under hydrostatic conditions. A pore pressure difference of up to 2 MPa was imposed across the ends of the sample. Fracture permeability decreased by 1–2 orders of magnitude during the 200–330 h experiments. Electron microprobe and SEM data indicated the formation of needle-shaped crystals of serpentine composition along the walls of the fracture, and chemical analyses of sampled pore fluids were consistent with dissolution of ferro-magnesian minerals. By comparing the difference between fracture permeability and matrix permeability measured on intact samples of the same rock types, we concluded that the contribution of the low matrix permeability to flow is negligible and essentially all of the flow is focused in the tensile fracture. The experimental results suggest that the fracture network in long-lived hydrothermal circulation systems can be sealed rapidly as a result of mineral precipitation, and generation of new permeability resulting from a combination of tectonic and crystallization-induced stresses is required to maintain fluid circulation.

Removing freon gas from hydraulic fluid

NASA Technical Reports Server (NTRS)

Williams, B. B.; Mitchell, S. M.; State, T. S.

1981-01-01

Dissolved freon gas is removed from hydraulic fluid by raising temperature to 150 F and bubbling dry nitrogen gas through it, even while fluid circulates through hydraulic system. Procedure reduces parts corrosion, sludge formation, and contamination.

Investigating cerebral oedema using poroelasticity.

PubMed

Vardakis, John C; Chou, Dean; Tully, Brett J; Hung, Chang C; Lee, Tsong H; Tsui, Po-Hsiang; Ventikos, Yiannis

2016-01-01

Cerebral oedema can be classified as the tangible swelling produced by expansion of the interstitial fluid volume. Hydrocephalus can be succinctly described as the abnormal accumulation of cerebrospinal fluid (CSF) within the brain which ultimately leads to oedema within specific sites of parenchymal tissue. Using hydrocephalus as a test bed, one is able to account for the necessary mechanisms involved in the interaction between oedema formation and cerebral fluid production, transport and drainage. The current state of knowledge about integrative cerebral dynamics and transport phenomena indicates that poroelastic theory may provide a suitable framework to better understand various diseases. In this work, Multiple-Network Poroelastic Theory (MPET) is used to develop a novel spatio-temporal model of fluid regulation and tissue displacement within the various scales of the cerebral environment. The model is applied through two formats, a one-dimensional finite difference - Computational Fluid Dynamics (CFD) coupling framework, as well as a two-dimensional Finite Element Method (FEM) formulation. These are used to investigate the role of endoscopic fourth ventriculostomy in alleviating oedema formation due to fourth ventricle outlet obstruction (1D coupled model) in addition to observing the capability of the FEM template in capturing important characteristics allied to oedema formation, like for instance in the periventricular region (2D model). Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

A Closed Loop System Using a Brine Reservoir to Replace Fresh Water as the Frac Fluid Source

EPA Pesticide Factsheets

A non-fresh water source, the Debolt formation, has been proposed and tested in the laboratory and field for application as a fracturing fluid in shale gas formations, with potential to replace much of the fresh water used in the Horn River Basin.

Formation of large-scale structures with sharp density gradient through Rayleigh-Taylor growth in a two-dimensional slab under the two-fluid and finite Larmor radius effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goto, R.; Hatori, T.; Miura, H., E-mail: miura.hideaki@nifs.ac.jp

Two-fluid and the finite Larmor effects on linear and nonlinear growth of the Rayleigh-Taylor instability in a two-dimensional slab are studied numerically with special attention to high-wave-number dynamics and nonlinear structure formation at a low β-value. The two effects stabilize the unstable high wave number modes for a certain range of the β-value. In nonlinear simulations, the absence of the high wave number modes in the linear stage leads to the formation of the density field structure much larger than that in the single-fluid magnetohydrodynamic simulation, together with a sharp density gradient as well as a large velocity difference. Themore » formation of the sharp velocity difference leads to a subsequent Kelvin-Helmholtz-type instability only when both the two-fluid and finite Larmor radius terms are incorporated, whereas it is not observed otherwise. It is shown that the emergence of the secondary instability can modify the outline of the turbulent structures associated with the primary Rayleigh-Taylor instability.« less

From hydrofracture to gaseofracture in porous rocks: influence of the nature of the injection fluid on the process

NASA Astrophysics Data System (ADS)

Johnsen, O.; Chevalier, C.; Toussaint, R.; Lindner, A.; Niebling, M.; Schmittbuhl, J.; Maloy, K. J.; Clement, E.; Flekkoy, E. G.

2009-04-01

We present experimental systems where we inject a fluid at high pressure in a poorly cohesive porous material saturated with the same fluid. This fluid is either a highly compressible gas (air), or an almost incompressible and viscous fluid (oil), in an otherwise identical porous matrix. We compare both situations. These porous materials are designed as analogs to real rocks in terms of processes, but their cohesion and geometry are tuned so that the hydrofracture process can be followed optically in the lab, in addition to the ability to follow the imposed pressure and fluxes. Namely, we work with lowly cohesive granular materials, confined in thin elongated Hele-Shaw cell, and follow it with high speed cameras. The fluid is injected on the side of the material, and the injection overpressure is maintained constant after the start. At sufficiently high overpressures, the mobilization of grains is observed, and the formation of hydrofracture fingering patterns is followed and analyzed quantitatively. The two situations where air is injected and where oil is injected are compared together. Many striking similarities are observed between both situations about the shape selections and dynamics, when time is rescaled according to the viscosity of the interstitial fluid. Some differences survive in the speed of the traveling hydrofracture, and their physical origin is discussed. In practice, this problem is relevant for important aspects in the formation and sustenance of increased permeability macroporous networks as demonstrated in nature and industry in many situations. E.g., in active hydrofracture in boreholes, piping/internal erosion in soils and dams, sand production in oil or water wells, and wormholes in oil sands. It is also important to understand the formation of macroporous channels, and the behavior of confined gouges when overpressured fluids are mobilized in seismic sources. Indeed, the formation of preferential paths in this situation can severely affect the fluid and heat transport properties in this situations, and thus affect the pore pressurization effects.

The Microgravity Research Experiments (MICREX) Data Base

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments) was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigator (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the importance of a low-gravity fluids and materials processing data base, (4) describes thE MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

The Microgravity Research Experiments (MICREX) Data Base, Volume 4

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical Memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

Dynamic response of fluid inside a penny shaped crack

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayashi, Kazuo; Seki, Hitoshi

1997-12-31

In order to discuss the method for estimating the geometric characteristics of geothermal reservoir cracks, a theoretical study is performed on the dynamic response of the fluid inside a reservoir crack in a rock mass subjected to a dynamic excitation due to propagation of an elastic wave. As representative models of reservoir cracks, a penny shaped crack and a two-dimensional crack which are connected to a borehole are considered. It is found that the resonance frequency of the fluid motion is dependent on the crack size, the fluid`s viscosity and the permeability of the formation. The intensity of the resonancemore » is dependent on the fluid`s viscosity when the size, the aperture and the permeability are fixed. It is also found that, at a value of the fluid`s viscosity, the resonance of fluid pressure becomes strongest. The optimum value of the fluid`s viscosity is found to be almost perfectly determined by the permeability of the formation. Furthermore, it is revealed that, if the fluid`s viscosity is fixed to be the optimum value, the resonance frequency is almost independent of the permeability and aperture, but is dependent on the size of crack. Inversely speaking, this implies that the size of the reservoir crack can be estimated from the resonance frequency, if the fluid with the above mentioned optimum value of viscosity is employed for hydraulic fracturing.« less

Fluid permeability measurement system and method

DOEpatents

Hallman, Jr., Russell Louis; Renner, Michael John [Oak Ridge, TN

2008-02-05

A system for measuring the permeance of a material. The permeability of the material may also be derived. The system provides a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.

Device for temporarily closing duct-formers in well completion apparatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zandmer, H.M.; Zandmer, S.M.

A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid resistant metal-such as steel-are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquidmore » into a position in which such fluid flow is prevented. After the fluid flow has been stopped by the closure device and when the formation pressure exceeds the pressure within the duct-forming device and the casing, fluid from the formation then forces the closure device toward and into the casing space to permit thereafter free flow of formation fluid into the duct-forming device and the casing or of pressurized treatment liquid from the casing into the formation. The inventive arrangement permits inter alia the establishment of a sufficient and substantially uniform feeding rate of treatment liquid, such as acid, from the casing into the producing formation through all the duct-formers in preparation for subsequent acidification or other treatments, such as sand fracking.« less

Hydroxyapatite formation on titania-based materials in a solution mimicking body fluid: Effects of manganese and iron addition in anatase.

PubMed

Shin, Euisup; Kim, Ill Yong; Cho, Sung Baek; Ohtsuki, Chikara

2015-03-01

Hydroxyapatite formation on the surfaces of implanted materials plays an important role in osteoconduction of bone substitutes in bone tissues. Titania hydrogels are known to instigate hydroxyapatite formation in a solution mimicking human blood plasma. To date, the relationship between the surface characteristics of titania and hydroxyapatite formation on its surface remains unclear. In this study, titania powders with varying surface characteristics were prepared by addition of manganese or iron to examine hydroxyapatite formation in a type of simulated body fluid (Kokubo solution). Hydroxyapatite formation was monitored by observation of deposited particles with scale-like morphology on the prepared titania powders. The effect of the titania surface characteristics, i.e., crystal structure, zeta potential, hydroxy group content, and specific surface area, on hydroxyapatite formation was examined. Hydroxyapatite formation was observed on the surface of titania powders that were primarily anatase, and featured a negative zeta potential and low specific surface areas irrespective of the hydroxy group content. High specific surface areas inhibited the formation of hydroxyapatite because calcium and phosphate ions were mostly consumed by adsorption on the titania surface. Thus, these surface characteristics of titania determine its osteoconductivity following exposure to body fluid. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of Salt, Pressure, and Water Activity on Homogeneous Ice Nucleation.

PubMed

Espinosa, Jorge R; Soria, Guiomar D; Ramirez, Jorge; Valeriani, Chantal; Vega, Carlos; Sanz, Eduardo

2017-09-21

Pure water can be substantially supercooled below the melting temperature without transforming into ice. The achievable supercooling can be enhanced by adding solutes or by applying hydrostatic pressure. Avoiding ice formation is of great importance in the cryopreservation of food or biological samples. In this Letter, we investigate the similarity between the effects of pressure and salt on ice formation using a combination of state-of-the-art simulation techniques. We find that both hinder ice formation by increasing the energetic cost of creating the ice-fluid interface. Moreover, we examine the widely accepted proposal that the ice nucleation rate for different pressures and solute concentrations can be mapped through the activity of water [ Koop , L. ; Tsias , P. Nature , 2000 , 406 , 611 ]. We show that such a proposal is not consistent with the nucleation rates predicted in our simulations because it does not include all parameters affecting ice nucleation. Therefore, even though salt and pressure have a qualitatively similar effect on ice formation, they cannot be quantitatively mapped onto one another.

Yield-stress fluids foams: flow patterns and controlled production in T-junction and flow-focusing devices.

PubMed

Laborie, Benoit; Rouyer, Florence; Angelescu, Dan E; Lorenceau, Elise

2016-11-23

We study the formation of yield-stress fluid foams in millifluidic flow-focusing and T-junction devices. First, we provide a phase diagram for the unsteady operating regimes of bubble production when the gas pressure and the yield-stress fluid flow rate are imposed. Three regimes are identified: a co-flow of gas and yield-stress fluid, a transient production of bubble and a flow of yield-stress fluid only. Taking wall slip into account, we provide a model for the pressure at the onset of bubble formation. Then, we detail and compare two simple methods to ensure steady bubble production: regulation of the gas pressure or flow-rate. These techniques, which are easy to implement, thus open pathways for controlled production of dry yield-stress fluid foams as shown at the end of this article.

Drop formation, pinch-off dynamics and liquid transfer of simple and complex fluids

NASA Astrophysics Data System (ADS)

Dinic, Jelena; Sharma, Vivek

Liquid transfer and drop formation processes underlying jetting, spraying, coating, and printing - inkjet, screen, roller-coating, gravure, nanoimprint hot embossing, 3D - often involve formation of unstable columnar necks. Capillary-driven thinning of such necks and their pinchoff dynamics are determined by a complex interplay of inertial, viscous and capillary stresses for simple, Newtonian fluids. Micro-structural changes in response to extensional flow field that arises within the thinning neck give rise to additional viscoelastic stresses in complex, non- Newtonian fluids. Using FLOW-3D, we simulate flows realized in prototypical geometries (dripping and liquid bridge stretched between two parallel plates) used for studying pinch-off dynamics and influence of microstructure and viscoelasticity. In contrast with often-used 1D or 2D models, FLOW-3D allows a robust evaluation of the magnitude of the underlying stresses and extensional flow field (both uniformity and magnitude). We find that the simulated radius evolution profiles match the pinch-off dynamics that are experimentally-observed and theoretically-predicted for model Newtonian fluids and complex fluids.

Are the Element Budget and the Occurrence of Polymetallic Nodules influenced by Fluids Circulating through the Oceanic Crust or/and Sediments?

NASA Astrophysics Data System (ADS)

Heller, C.; Kuhn, T.

2016-12-01

Hydrothermal fluids can extract significant amounts of heat from oceanic lithosphere by lateral fluid flow through permeable basaltic crust of an age of up to 65 Ma. Fluid recharge and discharge occur at basement outcrops in between impermeable pelagic sediments. Recharge of oxic seawater causes upward oxygen diffusion into sediments overlying the permeable basalt in areas proximal to recharge sites. It is suggested that this oxygen have a strong impact on sediments and Mn nodules during fluid exposure time. The aim of this study is to investigate if and how fluid flow through oceanic crust influence the distribution and element budget of the Mn nodules. For that purpose, Mn nodules were examined which were collected during the research cruise SO240 in the equatorial NE Pacific at sites with and without faults in the upper basement and overlying sediments. Faults are thought to be preferred fluid pathways. Nodules were found on the sediment surface as well as in the sediment and consist of different nm- to µm-thick, dense and porous layers. The geochemical composition of bulk nodules and single nodule layers were determined by XRF, ICP-MS/OES and by high resolution analyses with EMPA and LA-ICP-MS. Dense layers have low Mn/Fe ratios (<4) and high concentrations of Co, Zr and REY, while porous layers are characterized by high Mn/Fe ratios (> 10) and high Ni+Cu and Li concentrations (Koschinsky et al., 2010; Kuhn et al., 2010). The different compositions depends on different formation processes of the layers. Dense layers are formed by element precipitation from oxygen rich seawater and/or pore water and are called hydrogenetic, while porous layers were formed by precipitation from almost oxygen-free (suboxic) pore water (Burns & Burns, 1978; Glasby, 2006) and are called diagenetic (Halbach et al., 1988). Preliminary results show that there are significant differences between the geochemical composition of nodules grown at sediment surface and those found within sediments. Compared to surface nodules, buried nodules are enriched in Co and W, but has lower concentration of Mo, Ba, Zn, Li. Distribution of Rare Earth Elements (REY) are also different. Especially, the element distribution in the bulk samples and the single layers of the buried nodules could be used to find a possible influence of circulating fluids on nodule formation.

In-vitro bioactivity of zirconia doped borosilicate glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samudrala, Rajkumar; Azeem, P. Abdul, E-mail: rk.satyaswaroop@gmail.com, E-mail: drazeem2002@yahoo.com

2015-06-24

Glass composition 31B{sub 2}O{sub 3}-20SiO{sub 2}-24.5Na{sub 2}O-(24.5-x) CaO-xZrO{sub 2} x=1,2,3,4,5 were prepared by melt-quenching Technique. The formation of hydroxyapatite layer on the surface of glasses after immersion in simulated body fluid (SBF) was explored through XRD, Fourier transform infrared (FTIR) and Scanning electron microscopy (SEM-EDX) analyses. In this report, we observed that hydroxyapatite formation for 5days of immersion time. Also observed that with increasing the immersion time up to 15days, higher amount of hydroxyapatite layer formation on the surface of glasses. The varying composition of zirconia in glass samples influences shown by XRD, FTIR studies. The present results indicate that,more » in-vitro bioactivity of glasses decreased with increasing zirconia incorporation.« less

Geochemistry of fluids from Earth's deepest ridge-crest hot-springs: Piccard hydrothermal field, Mid-Cayman Rise

NASA Astrophysics Data System (ADS)

McDermott, Jill M.; Sylva, Sean P.; Ono, Shuhei; German, Christopher R.; Seewald, Jeffrey S.

2018-05-01

Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957-4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent fluids. To investigate the role of rock composition and deep circulation conditions on fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in high temperature vent fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support fluid formation at much higher temperatures in the subsurface. These high temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source fluid feeds high temperature vents across the entire Piccard field. High temperature Piccard fluid H2 abundances (19.9 mM) are even higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely high H2 abundances can be generated from fluid-basalt reaction occurring at very high temperatures. Magmatic and thermogenic sources of carbon in the high temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted fluid inclusions, and CO abundances are at equilibrium with the water-gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to high temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured temperature. A lack of ΣHCOOH in the relatively higher temperature 398 °C Beebe Vent fluids demonstrates the temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely high temperature fluid-rock reaction with mafic substrate as the dominant control on Piccard fluid chemistry. These results expand the known diversity of vent fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.

Selectivity enhancement in photoacoustic gas analysis via phase-sensitive detection at high modulation frequency

NASA Technical Reports Server (NTRS)

Kosterev, Anatoliy (Inventor)

2010-01-01

A method for detecting a target fluid in a fluid sample comprising a first fluid and the target fluid using photoacoustic spectroscopy (PAS), comprises a) providing a light source configured to introduce an optical signal having at least one wavelength into the fluid sample; b) modulating the optical signal at a desired modulation frequency such that the optical signal generates an acoustic signal in the fluid sample; c) measuring the acoustic signal in a resonant acoustic detector; and d) using the phase of the acoustic signal to detect the presence of the target fluid.

Slim hole drilling and testing strategies

NASA Astrophysics Data System (ADS)

Nielson, Dennis L.; Garg, Sabodh K.; Goranson, Colin

2017-12-01

The financial and geologic advantages of drilling slim holes instead of large production wells in the early stages of geothermal reservoir assessment has been understood for many years. However, the practice has not been fully embraced by geothermal developers. We believe that the reason for this is that there is a poor understanding of testing and reservoir analysis that can be conducted in slim holes. In addition to reservoir engineering information, coring through the cap rock and into the reservoir provides important data for designing subsequent production well drilling and completion. Core drilling requires significantly less mud volume than conventional rotary drilling, and it is typically not necessary to cure lost circulation zones (LCZ). LCZs should be tested by either production or injection methods as they are encountered. The testing methodologies are similar to those conducted on large-diameter wells; although produced and/or injected fluid volumes are much less. Pressure, temperature and spinner (PTS) surveys in slim holes under static conditions can used to characterize temperature and pressure distribution in the geothermal reservoir. In many cases it is possible to discharge slim holes and obtain fluid samples to delineate the geochemical properties of the reservoir fluid. Also in the latter case, drawdown and buildup data obtained using a downhole pressure tool can be employed to determine formation transmissivity and well properties. Even if it proves difficult to discharge a slim hole, an injection test can be performed to obtain formation transmissivity. Given the discharge (or injection) data from a slimhole, discharge properties of a large-diameter well can be inferred using wellbore modeling. Finally, slim hole data (pressure, temperature, transmissivity, fluid properties) together with reservoir simulation can help predict the ability of the geothermal reservoir to sustain power production.

Gas chromatographic analysis of volatiles in fluid and gas inclusions

USGS Publications Warehouse

Andrawes, F.; Holzer, G.; Roedder, E.; Gibson, E.K.; Oro, John

1984-01-01

Most geological samples and some synthetic materials contain fluid inclusions. These inclusions preserve for us tiny samples of the liquid and/or the gas phase that was present during formation, although in some cases they may have undergone significant changes from the original material. Studies of the current composition of the inclusions provide data on both the original composition and the change since trapping.These inclusions are seldom larger than 1 millimeter in diameter. The composition varies from a single major compound (e.g., water) in a single phase to a very complex mixture in one or more phases. The concentration of some of the compounds present may be at trace levels.We present here some analyses of inclusions in a variety of geological samples, including diamonds. We used a sample crusher and a gas chromatography—mass spectrometry (GC—MS) system to analyze for organic and inorganic volatiles present as major to trace constituents in inclusions. The crusher is a hardened stainless-steel piston cylinder apparatus with tungsten carbide crusing surfaces, and is operated in a pure helium atmosphere at a controlled temperature.Samples ranging from 1 mg to 1 g were crushed and the released volatiles were analyzed using multi-chromatographic columns and detectors, including the sensitive helium ionization detector. Identification of the GC peaks was carried out by GC—MS. This combination of procedures has been shown to provide geochemically useful information on the process involved in the history of the samples analyzed.

Gas chromatographic analysis of volatiles in fluid and gas inclusions.

PubMed

Andrawes, F; Holzer, G; Roedder, E; Gibson, E K; Oro, J

1984-01-01

Most geological samples and some synthetic materials contain fluid inclusions. These inclusions preserve for us tiny samples of the liquid and/or the gas phase that was present during formation, although in some cases they may have undergone significant changes from the original material. Studies of the current composition of the inclusions provide data on both the original composition and the change since trapping. These conclusions are seldom larger than 1 millimeter in diameter. The composition varies from a single major compound (e.g., water) in a single phase to a very complex mixture in one or more phases. The concentration of some of the compounds present may be at trace levels. We present here some analyses of inclusion on a variety of geological samples, including diamonds. We used a sample crusher and a gas chromatography-mass spectrometry (GC-MS) system to analyze for organic and inorganic volatiles present as major to trace constituents in inclusions. The crusher is a hardened stainless-steel piston cylinder apparatus with tungsten carbide crushing surfaces, and is operated in a pure helium atmosphere at a controlled temperature. Samples ranging from 1 mg to 1 g were crushed and the released volatiles were analyzed using multi-chromatographic columns and detectors, including the sensitive helium ionization detector. Identification of the GC peaks was carried out by GC-MS. This combination of procedures has been shown to provide geochemically useful information on the processes involved in the history of the samples analyzed.

A Numerical Study of Factors Affecting Fracture-Fluid Cleanup and Produced Gas/Water in Marcellus Shale: Part II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seales, Maxian B.; Dilmore, Robert; Ertekin, Turgay

Horizontal wells combined with successful multistage-hydraulic-fracture treatments are currently the most-established method for effectively stimulating and enabling economic development of gas-bearing organic-rich shale formations. Fracture cleanup in the stimulated reservoir volume (SRV) is critical to stimulation effectiveness and long-term well performance. But, fluid cleanup is often hampered by formation damage, and post-fracture well performance frequently falls to less than expectations. A systematic study of the factors that hinder fracture-fluid cleanup in shale formations can help optimize fracture treatments and better quantify long-term volumes of produced water and gas. Fracture-fluid cleanup is a complex process influenced by mutliphase flow through porousmore » media (relative permeability hysteresis, capillary pressure), reservoir-rock and -fluid properties, fracture-fluid properties, proppant placement, fracture-treatment parameters, and subsequent flowback and field operations. Changing SRV and fracture conductivity as production progresses further adds to the complexity of this problem. Numerical simulation is the best and most-practical approach to investigate such a complicated blend of mechanisms, parameters, their interactions, and subsequent effect on fracture-fluid cleanup and well deliverability. Here, a 3D, two-phase, dual-porosity model was used to investigate the effect of mutliphase flow, proppant crushing, proppant diagenesis, shut-in time, reservoir-rock compaction, gas slippage, and gas desorption on fracture-fluid cleanup and well performance in Marcellus Shale. Our findings have shed light on the factors that substantially constrain efficient fracture-fluid cleanup in gas shales, and we have provided guidelines for improved fracture-treatment designs and water management.« less

A Numerical Study of Factors Affecting Fracture-Fluid Cleanup and Produced Gas/Water in Marcellus Shale: Part II

DOE PAGES

Seales, Maxian B.; Dilmore, Robert; Ertekin, Turgay; ...

2017-04-01

Horizontal wells combined with successful multistage-hydraulic-fracture treatments are currently the most-established method for effectively stimulating and enabling economic development of gas-bearing organic-rich shale formations. Fracture cleanup in the stimulated reservoir volume (SRV) is critical to stimulation effectiveness and long-term well performance. But, fluid cleanup is often hampered by formation damage, and post-fracture well performance frequently falls to less than expectations. A systematic study of the factors that hinder fracture-fluid cleanup in shale formations can help optimize fracture treatments and better quantify long-term volumes of produced water and gas. Fracture-fluid cleanup is a complex process influenced by mutliphase flow through porousmore » media (relative permeability hysteresis, capillary pressure), reservoir-rock and -fluid properties, fracture-fluid properties, proppant placement, fracture-treatment parameters, and subsequent flowback and field operations. Changing SRV and fracture conductivity as production progresses further adds to the complexity of this problem. Numerical simulation is the best and most-practical approach to investigate such a complicated blend of mechanisms, parameters, their interactions, and subsequent effect on fracture-fluid cleanup and well deliverability. Here, a 3D, two-phase, dual-porosity model was used to investigate the effect of mutliphase flow, proppant crushing, proppant diagenesis, shut-in time, reservoir-rock compaction, gas slippage, and gas desorption on fracture-fluid cleanup and well performance in Marcellus Shale. Our findings have shed light on the factors that substantially constrain efficient fracture-fluid cleanup in gas shales, and we have provided guidelines for improved fracture-treatment designs and water management.« less

Concentration of aluminium in breast cyst fluids collected from women affected by gross cystic breast disease.

PubMed

Mannello, Ferdinando; Tonti, Gaetana A; Darbre, Philippa D

2009-01-01

Gross cystic breast disease (GCBD) is the most common benign breast disorder, but the molecular basis of cyst formation remains to be identified. If the use of aluminium-based antiperspirant salts is involved in the etiology of gross breast cyst formation, it might be expected that aluminium would be at elevated levels in human breast cyst fluid (BCF). Aluminium was measured by ICP-MS in 48 samples of BCF, 30 samples of human blood serum and 45 samples of human breast milk at different stages of lactation (colostrum, intermediate, mature). The median level of aluminium in apocrine type I BCF (n = 27, 150 microg l(-1)) was significantly higher than in transudative type II BCF (n = 21, 32 microg l(-1); P < 0.0001). By comparison, aluminium measurements gave a median concentration of 6 microg l(-1) in human serum and 25 microg l(-1) in human breast milk, with no difference between colostrum, intermediate and mature milk. Levels of aluminium were significantly higher in both types of BCF than in human serum (P < 0.0001). However when compared with human breast milk, aluminium levels were only significantly higher in apocrine type I BCF (P < 0.0001) and not in transudative type II BCF (P = 0.152). It remains to be identified why such high levels of aluminium were found in the apocrine type I BCF and from where the aluminium originated. However, if aluminium-based antiperspirants are found to be the source and to play any causal role in development of breast cysts, then it might become possible to prevent this common breast disorder. Copyright (c) 2008 John Wiley & Sons, Ltd.

Comparative research of effectiveness of cellulose and fiberglass porous membrane carriers for bio sampling in veterinary and food industry monitoring

NASA Astrophysics Data System (ADS)

Gusev, Alexander; Vasyukova, Inna; Zakharova, Olga; Altabaeva, Yuliya; Saushkin, Nikolai; Samsonova, Jeanne; Kondakov, Sergey; Osipov, Alexander; Snegin, Eduard

2017-11-01

The aim of proposed research is to study the applicability of fiberglass porous membrane materials in a new strip format for dried blood storage in food industry monitoring. A comparative analysis of cellulosic and fiberglass porous membrane materials was carried out to obtain dried samples of serum or blood and the possibility of further species-specific analysis. Blood samples of Sus scrofa were used to study the comparative effectiveness of cellulose and fiberglass porous membrane carriers for long-term biomaterial storage allowing for further DNA detection by real-time polymerase chain reaction (PCR) method. Scanning electron microscopy of various membranes - native and with blood samples - indicate a fundamental difference in the form of dried samples. Membranes based on cellulosic materials sorb the components of the biological fluid on the surface of the fibers of their structure, partially penetrating the cellulose fibers, while in the case of glass fiber membranes the components of the biological fluid dry out as films in the pores of the membrane between the structural filaments. This fundamental difference in the retention mechanisms affects the rate of dissolution of the components of dry samples and contributes to an increase in the efficiency of the desorption process of the sample before subsequent analysis. Detecting of pig DNA in every analyzed sample under the performed Real-time PCR as well as good state of the biomaterial preservation on the glass fiber membranes was clearly demonstrated. Good biomaterials preservation has been revealed on the test cards for 4 days as well as for 1 hour.

Ground testing of bioconvective variables such as morphological characterizations and mechanisms which regulate macroscopic patterns

NASA Technical Reports Server (NTRS)

Johnson, Adriel D.

1992-01-01

Conditions simulating low- and high-gravity, reveal changes in macroscopic pattern formation in selected microorganisms, but whether these structures are gravity dependent is not clear. Two theories have been identified in the fluid dynamics community which support macroscopic pattern formation. The first one is gravity dependent (fluid density models) where small concentrated regions of organisms sink unstably, and the second is gravity independent (wave reinforcement theory) where organisms align their movements in concert, such that either their swimming strokes beat in phase or their vortices entrain neighbors to follow parallel paths. Studies have shown that macroscopic pattern formation is consistent with the fluid density models for protozoa and algae and wave reinforcement hypothesis for caprine spermatozoa.

S- and Sr-isotopic compositions in barite-silica chimney from the Franklin Seamount, Woodlark Basin, Papua New Guinea: constraints on genesis and temporal variability of hydrothermal fluid

NASA Astrophysics Data System (ADS)

Ray, Durbar; Banerjee, Ranadip; Balakrishnan, S.; Paropkari, Anil L.; Mukhopadhyay, Subir

2017-07-01

Isotopic ratios of strontium and sulfur in six layers across a horizontal section of a hydrothermal barite-silica chimney from Franklin Seamount of western Woodlark Basin have been investigated. Sr-isotopic ratios in barite samples (87Sr/86Sr = 0.70478-0.70493) are less radiogenic than seawater (87Sr/86Sr = 0.70917) indicating that substantial leaching of sub-seafloor magma was involved in the genesis of hydrothermal fluid. The SO2 of magma likely contributed a considerable amount of lighter S-isotope in fluid and responsible for the formation of barite, which is isotopically lighter (δ34S = 19.4-20.5 ‰) than modern seawater (δ34S 21 ‰). The systematic changes in isotopic compositions across the chimney wall suggest temporal changes in the mode of mineral formation during the growth of the chimney. Enrichment of heavy S- and Sr-isotopes (δ34S = 20.58 ‰; 87Sr/86Sr = 0.70493) in the outermost periphery of the chimney indicates that, at the initial stage of chimney development, there was a significant contribution of seawater sulfate during barite mineralization. Thereafter, thickening of chimney wall occurred due to precipitation of fluid carrying more magmatic components relative to seawater. This led to a gradual enrichment of lighter isotopes (δ34S = 20.42-19.48 ‰; 87Sr/86Sr = 0.70491-0.704787) toward the inner portion of the chimney wall. In contrast, the innermost layer surrounding the fluid conduit is characterized by heavier and more radiogenic isotopes (δ34S = 20.3 ‰; 87Sr/86Sr = 0.7049). This suggests there was increasing influence of percolating seawater on the mineral paragenesis at the waning phase of the chimney development.

C-O-H-S magmatic fluid system in shrinkage bubbles of melt inclusions

NASA Astrophysics Data System (ADS)

Robidoux, P.; Frezzotti, M. L.; Hauri, E. H.; Aiuppa, A.

2016-12-01

Magmatic volatiles include multiple phases in the C-O-H-S system of shrinkage bubbles for which a conceptual model is still unclear during melt inclusion formation [1,2,3,4]. The present study aims to qualitatively explore the evolution of the volatile migration, during and after the formation of the shrinkage bubble in melt inclusions trapped by olivines from Holocene to present at San Cristóbal volcano (Nicaragua), Central American Volcanic Arc (CAVA). Combined scanning electron microscope (SEM) and Raman spectroscopy observations allow to define the mineral-fluid phases inside typical shrinkage bubbles at ambient temperature. The existence of residual liquid water is demonstrated in the shrinkage bubbles of naturally quenched melt inclusion and this water could represents the principal agent for chemical reactions with other dissolved ionic species (SO42-, CO32-, etc.) and major elements (Mg, Fe, Cu, etc.) [4,5]. With the objective of following the cooling story of the bubble-inclusion system, the new methodological approach here estimate the interval of equilibrium temperatures for each SEM-Raman identified mineral phase (carbonates, hydrous carbonates, sulfurs, sulfates, etc.). Finally, two distinct mechanisms are proposed to describe the evolution of this heterogeneous fluid system in bubble samples at San Cristóbal which imply a close re-examination for similar volcanoes in subduction zone settings: (1) bubbles are already contracted and filled by volatiles by diffusion processes from the glass and leading to a C-O-H-S fluid-glass reaction enriched in Mg-Fe-Cu elements (2) bubbles are formed by oversaturation of the volatiles from the magma which is producing an immiscible metal-rich fluid. [1]Moore et al. (2015). Am. Mineral. 100, 806-823 [2]Wallace et al. (2015). Am. Mineral. 100, 787-794 [3]Lowenstern (2015). Am. Mineral. 100, 672-673 [4]Esposito, et al. (2016). Am. Mineral. 101, 1691-1708 [5]Kamenetsky et al. (2001). Earth Planet. Sci. Lett. 184, 685-702

Microfracturing and fluid pathways in serpentinizing abyssal peridotites along the Southwest Indian Ridge (62°-65°E)

NASA Astrophysics Data System (ADS)

Rouméjon, S.; Cannat, M.; Agrinier, P.; Godard, M.; Andreani, M.

2013-12-01

At slow spreading ridges, axial detachment faults exhume mantle-derived peridotites. Their interaction with seawater-derived hydrothermal fluids causes serpentinization down to 2-3km from the fault, as inferred from seismic velocity models. It is commonly proposed that fractures allow penetration of seawater into the fault's footwall. At the microscopic scale, the hydration front progresses from a microfracture network toward the center of olivine relicts and forms the serpentine mesh texture. The origin of these microfractures is a matter of debate: tectonic, anisotropic thermal contraction of olivine during peridotite cooling or hierarchical fracturing of the olivine due to volume increase during serpentinization. In this presentation we use petrology and geochemistry to analyze the links between microfractures and serpentinization in a set of highly serpentinized peridotites dredged along the melt-starved easternmost part of the Southwest Indian Ridge (Smoothseafloor cruise). Our observations suggest that thermal contraction of olivine combines with tectonic stresses to fracture fresh peridotite in the brittle lithosphere. These ~60μm-spaced microfractures constitute the initial sample-scale permeability network for fluid penetration, onset of serpentinization and formation of additional hierarchical fractures. As serpentinization proceeds, the volume increase closes the least-developed planes and preferential pathways for fluid circulation become more distant, forming the 200-500μm-wide polygonal pattern typical of the serpentine mesh texture. In about 20% of the recovered samples the mesh serpentine is partially recrystallized forming rims next to later microfractures and serpentine veins. The spacing of these rims, and the limited proportion of affected samples suggest that the scales of the efficient permeability network in the serpentinites at this stage had increased to decimetric and greater scales. We use geochemical constrains to derive temperature conditions associated with this serpentinization history and to discuss the nature of serpentinizing fluids, based on a comparison with published work on serpentinites from the Mid-Atlantic Ridge. δ18O values decrease from 5.98‰ to 1.91‰, from mesh texture serpentine to the later recrystallized serpentines. These values probably correspond to temperatures on the order of 200-300°C and to a progressive equilibration with serpentinizing fluid values due to increasing water-rock ratios. Fluid-rock interactions produce serpentine minerals that are enriched in fluid-mobile elements (B, As, Sb, U, Cu) compared to primary minerals in the peridotites and present occasional Eu anomalies that may reflect variable redox conditions during serpentinization.

Rapid detection of rRNA group I pseudomonads in contaminated metalworking fluids and biofilm formation by fluorescent in situ hybridization.

PubMed

Saha, Ratul; Donofrio, Robert S; Goeres, Darla M; Bagley, Susan T

2012-05-01

Metalworking fluids (MWFs), used in different machining operations, are highly prone to microbial degradation. Microbial communities present in MWFs lead to biofilm formation in the MWF systems, which act as a continuous source of contamination. Species of rRNA group I Pseudomonas dominate in contaminated MWFs. However, their actual distribution is typically underestimated when using standard culturing techniques as most fail to grow on the commonly used Pseudomonas Isolation Agar. To overcome this, fluorescent in situ hybridization (FISH) was used to study their abundance along with biofilm formation by two species recovered from MWFs, Pseudomonas fluorescens MWF-1 and the newly described Pseudomonas oleovorans subsp. lubricantis. Based on 16S rRNA sequences, a unique fluorescent molecular probe (Pseudo120) was designed targeting a conserved signature sequence common to all rRNA group I Pseudomonas. The specificity of the probe was evaluated using hybridization experiments with whole cells of different Pseudomonas species. The probe's sensitivity was determined to be 10(3) cells/ml. It successfully detected and enumerated the abundance and distribution of Pseudomonas indicating levels between 3.2 (± 1.1) × 10(6) and 5.0 (± 2.3) × 10(6) cells/ml in four different industrial MWF samples collected from three different locations. Biofilm formation was visualized under stagnant conditions using high and low concentrations of cells for both P. fluorescens MWF-1 and P. oleovorans subsp. lubricantis stained with methylene blue and Pseudo120. On the basis of these observations, this molecular probe can be successfully be used in the management of MWF systems to monitor the levels and biofilm formation of rRNA group I pseudomonads.

Evidence Report: Risk of Renal Stone Formation

NASA Technical Reports Server (NTRS)

Sibonga, Jean D.; Pietrzyk, Robert

2017-01-01

The formation of renal stones poses an in-flight health risk of high severity, not only because of the impact of renal colic on human performance but also because of complications that could potentially lead to crew evacuation, such as hematuria, infection, hydronephrosis, and sepsis. Evidence for risk factors comes from urine analyses of crewmembers, documenting changes to the urinary environment that are conducive to increased saturation of stone-forming salts, which are the driving force for nucleation and growth of a stone nidus. Further, renal stones have been documented in astronauts after return to Earth and in one cosmonaut during flight. Biochemical analysis of urine specimens has provided indication of hypercalciuria and hyperuricemia, reduced urine volumes, and increased urine saturation of calcium oxalate and calcium phosphate. A major contributor to the risk for renal stone formation is bone atrophy with increased turnover of the bone minerals. Dietary and fluid intakes also play major roles in the risk because of the influence on urine pH (more acidic) and on volume (decreased). Historically, specific assessments on urine samples from some Skylab crewmembers indicated that calcium excretion increased early in flight, notable by day 10 of flight, and almost exceeded the upper threshold for normal excretion (300mg/day in males). Other crewmember data documented reduced intake of fluid and reduced intake of potassium, phosphorus, magnesium, and citrate (an inhibitor of calcium stone formation) in the diet. Hence, data from both short-duration and long-duration missions indicate that space travel induces risk factors for renal stone formation that continue to persist after flight; this risk has been documented by reported kidney stones in crewmembers.

Reservoir fluid and gas chemistry during CO2 injection at the Cranfield field, Mississippi, USA

NASA Astrophysics Data System (ADS)

Lu, J.; Kharaka, Y. K.; Cole, D. R.; Horita, J.; Hovorka, S.

2009-12-01

At Cranfield field, Mississippi, USA, a monitored CO2-EOR project provides a unique opportunity to understand geochemical interactions of injected CO2 within the reservoir. Cranfield field, discovered in 1943, is a simple anticlinal four-way closure and had a large gas cap surrounded by an oil ring (Mississippi Oil and Gas Board, 1966). The field was abandoned in 1966. The reservoir returned to original reservoir pressure (hydrostatic pressure) by a strong aquifer drive by 2008. The reservoir is in the lower Tuscaloosa Formation at depths of more than 3000 m. It is composed of stacked and incised channel fills and is highly heterogeneous vertically and horizontally. A variable thickness (5 to 15 m) of terrestrial mudstone directly overlies the basal sandstone providing the primary seal, isolating the injection interval from a series of fluvial sand bodies occurring in the overlying 30 m of section. Above these fluvial channels, the marine mudstone of the Middle Tuscaloosa forms a continuous secondary confining system of approximately 75 m. The sandstones of the injection interval are rich in iron, containing abundant diagenetic chamosite (ferroan chlorite), hematite and pyrite. Geochemical modeling suggests that the iron-bearing minerals will be dissolved in the face of high CO2 and provide iron for siderite precipitation. CO2 injection by Denbury Resources Inc. begun in mid-July 2008 on the north side of the field with rates at ~500,000 tones per year. Water and gas samples were taken from seven production wells after eight months of CO2 injection. Gas analyses from three wells show high CO2 concentrations (up to 90 %) and heavy carbon isotopic signatures similar to injected CO2, whereas the other wells show original gas composition and isotope. The mixing ratio between original and injected CO2 is calculated based on its concentration and carbon isotope. However, there is little variation in fluid samples between the wells which have seen various levels of CO2. Comparison between preinjection and postinjection fluid analyses also shows little difference. It suggests that CO2 injection has not induced significant mineral-water reactions to change water chemistry. In October 2009, CO2 will be injected into the down-dip, non-productive Tuscaloosa Formation on the east side of the same field. In-situ fluid and gas samples will be collected using downhole U-tube. Fluid chemistry data through time will reveal mineral reactions during and after injection and confine timescales of the interactions. This project was funded thought the National Energy Technology Laboratory Regional Carbon Sequestration Partnership Program as part of the Southeast Regional Carbon Sequestration Partnership.

Renal Epithelial Cyst Formation and Enlargement in vitro: Dependence on cAMP

NASA Astrophysics Data System (ADS)

Mangoo-Karim, Roberto; Uchic, Marie; Lechene, Claude; Grantham, Jared J.

1989-08-01

Cysts, a common abnormality of kidneys, are collections of urine-like fluid enclosed by a continuous layer of epithelial cells. Renal cysts derive from nephrons and collecting ducts and progressively enlarge as a consequence of epithelial proliferation and transepithelial fluid secretion. The initiation of cyst formation and the factors that control cyst enlargement are unknown. We used an in vitro model of renal cysts to explore the role of the cAMP signal transduction system in the formation and expansion of cysts. MDCK cells, cultured in hydrated-collagen gel, produced polarized monolayered epithelial cysts when intracellular cAMP was increased by prostaglandin E1, arginine vasopressin, cholera toxin, forskolin, or 8-bromoadenosine 3',5'-cyclic monophosphate. All agonists were potentiated by 3-isobutyl-1-methylxanthine, a nucleotide phosphodiesterase inhibitor. The cell proliferation component of cyst enlargement was accelerated by cAMP agonists, as shown by the increased growth of MDCK cells in subconfluent monolayers. The fluid secretion component, reflected by the transepithelial movement of fluid across polarized monolayers of MDCK cells grown on permeable supports, was stimulated by cAMP agonists in the basolateral medium. Chloride levels were higher in the cyst fluid and the secreted fluid than in the bathing medium. We conclude that the development of MDCK cysts is dependent on cAMP. This signal transduction system may be an important modulator of epithelial cell proliferation and transepithelial fluid secretion in the kidney.

Soy Protein Isolate As Fluid Loss Additive in Bentonite-Water-Based Drilling Fluids.

PubMed

Li, Mei-Chun; Wu, Qinglin; Song, Kunlin; Lee, Sunyoung; Jin, Chunde; Ren, Suxia; Lei, Tingzhou

2015-11-11

Wellbore instability and formation collapse caused by lost circulation are vital issues during well excavation in the oil industry. This study reports the novel utilization of soy protein isolate (SPI) as fluid loss additive in bentonite-water based drilling fluids (BT-WDFs) and describes how its particle size and concentration influence on the filtration property of SPI/BT-WDFs. It was found that high pressure homogenization (HPH)-treated SPI had superior filtration property over that of native SPI due to the improved ability for the plugging pore throat. HPH treatment also caused a significant change in the surface characteristic of SPI, leading to a considerable surface interaction with BT in aqueous solution. The concentration of SPI had a significant impact on the dispersion state of SPI/BT mixtures in aquesous solution. At low SPI concentrations, strong aggregations were created, resulting in the formation of thick, loose, high-porosity and high-permeability filter cakes and high fluid loss. At high SPI concentrations, intercatlated/exfoliated structures were generated, resulting in the formation of thin, compact, low-porosity and low-permeability filter cakes and low fluid loss. The SPI/BT-WDFs exhibited superior filtration property than pure BT-WDFs at the same solid concentraion, demonstrating the potential utilization of SPI as an effective, renewable, and biodegradable fluid loss reducer in well excavation applications.

ToF-SIMS images and spectra of biomimetic calcium silicate-based cements after storage in solutions simulating the effects of human biological fluids

NASA Astrophysics Data System (ADS)

Torrisi, A.; Torrisi, V.; Tuccitto, N.; Gandolfi, M. G.; Prati, C.; Licciardello, A.

2010-01-01

ToF-SIMS images were obtained from a section of a tooth, obturated by means of a new calcium-silicate based cement (wTCF) after storage for 1 month in a saline solutions (DPBS), in order to simulate the body fluid effects on the obturation. Afterwards, ToF-SIMS spectra were obtained from model samples, prepared by using the same cement paste, after storage for 1 month and 8 months in two different saline solutions (DPBS and HBSS). ToF-SIMS spectra were also obtained from fluorine-free cement (wTC) samples after storage in HBSS for 1 month and 8 months and used for comparison. It was found that the composition of both the saline solution and the cement influenced the composition of the surface of disks and that longer is the storage greater are the differences. Segregation phenomena occur both on the cement obturation of the tooth and on the surface of the disks prepared by using the same cement. Indirect evidences of formation of new crystalline phases are supplied.

Subsurface Formation Evaluation on Mars: Application of Methods from the Oil Patch

NASA Astrophysics Data System (ADS)

Passey, Q. R.

2006-12-01

The ability to drill 10- to 100-meter deep wellbores on Mars would allow for evaluation of shallow subsurface formations enabling the extension of current interpretations of the geologic history of this planet; moreover, subsurface access is likely to provide direct evidence to determine if water or permafrost is present. Methodologies for evaluating sedimentary rocks using drill holes and in situ sample and data acquisition are well developed here on Earth. Existing well log instruments can measure K, Th, and U from natural spectral gamma-ray emission, compressional and shear acoustic velocities, electrical resistivity and dielectric properties, bulk density (Cs-137 or Co-60 source), photoelectric absorption of gamma-rays (sensitive to the atomic number), hydrogen index from epithermal and thermal neutron scattering and capture, free hydrogen in water molecules from nuclear magnetic resonance, formation capture cross section, temperature, pressure, and elemental abundances (C, O, Si, Ca, H, Cl, Fe, S, and Gd) using 14 MeV pulsed neutron activation more elements possible with supercooled Ge detectors. Additionally, high-resolution wellbore images are possible using a variety of optical, electrical, and acoustic imaging tools. In the oil industry, these downhole measurements are integrated to describe potential hydrocarbon reservoir properties: lithology, mineralogy, porosity, depositional environment, sedimentary and structural dip, sedimentary features, fluid type (oil, gas, or water), and fluid amount (i.e., saturation). In many cases it is possible to determine the organic-carbon content of hydrocarbon source rocks from logs (if the total organic carbon content is 1 wt% or greater), and more accurate instruments likely could be developed. Since Martian boreholes will likely be drilled without using opaque drilling fluids (as generally used in terrestrial drilling), additional instruments can be used such as high resolution direct downhole imaging and other surface contact measurements (such as IR spectroscopy and x-ray fluorescence). However, such wellbores would require modification of some instruments since conventional drilling fluids often provide the coupling of the instrument sensors to the formation (e.g., sonic velocity and galvanic resistivity measurements). The ability to drill wellbores on Mars opens up new opportunities for exploration but also introduces additional technical challenges. Currently it is not known if all existing terrestrial logging instruments can be miniaturized sufficiently for a shallow Mars wellbore, but the existing well logging techniques and instruments provide a solid framework on which to build a Martian subsurface evaluation program.

Revealing fate of CO2 leakage pathways in the Little Grand Wash Fault, Green River, Utah

NASA Astrophysics Data System (ADS)

Han, K.; Han, W. S.; Watson, Z. T.; Guyant, E.; Park, E.

2015-12-01

To assure long-term security of geologic carbon sequestration site, evaluation of natural CO2 leakage should be preceded before actual construction of the CO2 facility by comparing natural and artificial reservoir systems. The Little Grand Wash fault is located at the northwestern margin of the Paradox Basin and roles on a bypass of deep subsurface CO2 and brine water onto the surface, e.g., cold water geyser, CO2 spring, and surface travertine deposits. CO2 degassed out from brine at the Little Grand Wash fault zone may react with formation water and minerals while migrating through the fault conduit. Leakage observed by soil CO2 flux on the fault trace shows this ongoing transition of CO2, from supersaturated condition in deep subsurface to shallow surface equilibria. The present study aims to investigate the reactions induced by changes in hydrological and mineralogical factors inside of the fault zone. The methodology to develop site-specific geochemical model of the Little Grand Wash Fault combines calculated mechanical movements of each fluid end-member, along with chemical reactions among fluid, free CO2 gas and rock formations. Reactive transport modeling was conducted to simulate these property changes inside of the fault zone, using chemistry dataset based on 86 effluent samples of CO2 geysers, springs and in situ formation water from Entrada, Carmel, and Navajo Sandstone. Meanwhile, one- and two-dimensional models were separately developed to delineate features mentioned above. The results from the 3000-year simulation showed an appearance of self-sealing processes near the surface of the fault conduit. By tracking physicochemical changes at the depth of 15 m on the 2-dimensional model, significant changes induced by fluid mixing were indicated. Calculated rates of precipitation for calcite, illite, and pyrite showed increase in 2.6 x 10-4, 2.25 x 10-5, and 3.0 x 10-6 in mineral volume fraction at the depth of 15m, respectively. Concurrently, permeability and porosity were decreased 4.0 x 10-18 m2 and 3.0 x 10-4 due to precipitation of minerals. At the middle of the fault conduit (400 m), however, indicates consistent dissolution of minerals in formation which enhances vertical fluid migration.

Method for laser drilling subterranean earth formations

DOEpatents

Shuck, Lowell Z.

1976-08-31

Laser drilling of subterranean earth formations is efficiently accomplished by directing a collimated laser beam into a bore hole in registry with the earth formation and transversely directing the laser beam into the earth formation with a suitable reflector. In accordance with the present invention, the bore hole is highly pressurized with a gas so that as the laser beam penetrates the earth formation the high pressure gas forces the fluids resulting from the drilling operation into fissures and pores surrounding the laser-drilled bore so as to inhibit deleterious occlusion of the laser beam. Also, the laser beam may be dynamically programmed with some time dependent wave form, e.g., pulsed, to thermally shock the earth formation for forming or enlarging fluid-receiving fissures in the bore.

Diamond formation through isochemical cooling of CHO fluids vs redox buffering: examples from Marange peridotitic and Zimmi eclogitic diamonds

NASA Astrophysics Data System (ADS)

Smit, Karen V.; Stachel, Thomas; Stern, Richard A.; Shirey, Steven B.; Steele, Andrew

2017-04-01

Traditional models for diamond formation within the lithospheric mantle invoke either carbonate reduction or methane oxidation. Both these mechanisms require some oxygen exchange with the surrounding wall-rock at the site of diamond precipitation. However, peridotite does not have sufficient buffering capacity to allow for diamond formation via these traditional models and instead peridotitic diamonds may form through isochemical cooling of H2O-rich CHO fluids [1]. Marange mixed-habit diamonds from eastern Zimbabwe provide the first natural confirmation of this new diamond growth model [2]. Although Marange diamonds do not contain any silicate or sulphide inclusions, they contain Ni-N-vacancy complexes detected through photoluminescence (PL) spectroscopy that suggest the source fluids equilibrated in the Ni-rich depleted peridotitic lithosphere. Cuboid sectors also contain abundant micro-inclusions of CH4, the first direct observation of reduced CH4-rich fluids that are thought to percolate through the lithospheric mantle [2]. In fluid inclusion-free diamonds, core-to-rim trends in δ13C and N content are used to infer the speciation of the diamond-forming fluid. Core to rim trends of increasing δ13C with decreasing N content are interpreted as diamond growth from oxidized CO2- or carbonate-bearing fluids. Diamond growth from reduced species should show the opposite trends - decreasing δ13C from core to rim with decreasing N content. Within the CH4-bearing growth sectors of Marange diamonds, however, such a 'reduced' trend is not observed. Rather, δ13C increases from core to rim within a homogeneously grown zone [2]. These contradictory observations can be explained through either mixing between CH4- and CO2-rich end-members of hydrous fluids [2] or through closed system precipitation from an already mixed CH4-CO2 H2O-maximum fluid with XCO2 (CO2/[CO2+CH4]) between 0.3 and 0.7 [3]. These results demonstrate that Marange diamonds precipitated from cooling CH4-CO2-bearing hydrous fluids rather than through redox buffering. As this growth mechanism applies to both the fluid-rich cuboid and gem-like octahedral sectors of Marange diamonds, a non-redox model for diamond formation from mixed CH4-CO2 fluids is indicated for a wider range of gem-quality peridotitic diamonds. Indeed, at the redox conditions of global diamond-bearing lithospheric mantle (FMQ -2 to -4; [4]), CHO fluids are strongly water-dominated and contain both CH4 and CO2 as dominant carbon species [5]. By contrast diamond formation in eclogitic assemblages, through either redox buffering or cooling of carbon-bearing fluids, is not as well constrained. Zimmi diamonds from the West African craton have eclogitic sulphide inclusions (with low Ni and high Re/Os) and formed at 650 Ma, overlapping with the timing of subduction [6]. In one Zimmi diamond, a core to rim trend of decreasing δ13C (-23.4 to -24.5 ) and N content is indicative of formation from reduced C2H6/CH4-rich fluids, likely derived from oceanic crust recycled during Neoproterozoic subduction. Unlike mixed CH4-CO2 fluids near the water maximum, isochemical cooling or ascent of such reduced CHO fluids is not effficient at diamond precipitation. Furthermore, measurable carbon isotopic variations in diamond are not predicted in this model and therefore cannot be reconciled with the ˜1 ‰ internal variation seen. Consequently, this Zimmi eclogitic diamond likely formed through redox buffering of reduced subduction-related fluids, infiltrating into sulphide-bearing eclogite. References 1. Luth and Stachel, 2014. CMP, 168, 1083 2. Smit et al., 2016. Lithos, 265, 68-81 3. Stachel et al., in review 4. Stagno et al., 2013. Nature, 493, 84-88 5. Zhang and Duan, 2009. GCA 73, 2089-2102 6. Smit et al., 2016. Precamb Res, 286, 152-166

Detection of Classical swine fever virus infection by individual oral fluid of pigs following experimental inoculation.

PubMed

Petrini, Stefano; Pierini, Ilaria; Giammarioli, Monica; Feliziani, Francesco; De Mia, Gian Mario

2017-03-01

We evaluated the use of oral fluid as an alternative to serum samples for Classical swine fever virus (CSFV) detection. Individual oral fluid and serum samples were collected at different times post-infection from pigs that were experimentally inoculated with CSFV Alfort 187 strain. We found no evidence of CSFV neutralizing antibodies in swine oral fluid samples under our experimental conditions. In contrast, real-time reverse transcription-polymerase chain reaction could detect CSFV nucleic acid from the oral fluid as early as 8 d postinfection, which also coincided with the time of initial detection in blood samples. The probability of CSFV detection in oral fluid was identical or even higher than in the corresponding blood sample. Our results support the feasibility of using this sampling method for CSFV genome detection, which may represent an additional cost-effective tool for CSF control.

Determination of the Landau Lifshitz damping parameter of composite magnetic fluids

NASA Astrophysics Data System (ADS)

Fannin, P. C.; Malaescu, I.; Marin, C. N.

2007-01-01

Measurements of the frequency dependent, complex magnetic susceptibility, χ(ω)= χ‧( ω)- iχ″( ω), in the GHz range, are used to investigate the effect which the mixing of two different magnetic fluids has on the value of the damping parameter, α, of the Landau-Lifshitz equation. The magnetic fluid samples investigated in this study were three kerosene-based magnetic fluids, stabilised with oleic acid, denoted as MF1, MF2 and MF3. Sample MF1 was a magnetic fluid with Mn 0.6Fe 0.4Fe 2O 4 particles, sample MF2 was a magnetic fluid with Ni 0.4Zn 0.6Fe 2O 4 particles and sample MF3 was a composite magnetic fluid obtained by mixing a part of sample MF1 with a part of sample MF2, in proportion of 1:1. The experimental results revealed that the value of the damping parameter of the composite sample (sample MF3) is between the α values obtained for its constituents (samples MF1 and MF2). Based on the superposition principle, which states that the susceptibility of a magnetic fluid sample is a superposition of individual contributions of the magnetic particles, a theoretical model is proposed. The experimental results are shown to be in close agreement with the theoretical results. This result is potentially useful in the design of microwave-operating materials, in that it enables one to determine a particular value of damping parameter.

FLUID SELECTING APPARATUS

DOEpatents

Stinson, W.J.

1958-09-16

A valve designed to selectively sample fluids from a number of sources is described. The valve comprises a rotatable operating lever connected through a bellows seal to a rotatable assembly containing a needle valve, bearings, and a rotational lock. The needle valve is connected through a flexible tube to the sample fluid outlet. By rotating the lever the needle valve is placed over . one of several fluid sources and locked in position so that the fluid is traasferred through the flexible tubing and outlet to a remote sampling system. The fluids from the nonselected sources are exhausted to a waste line. This valve constitutes a simple, dependable means of selecting a sample from one of several scurces.

Reservoir Condition Pore-scale Imaging of Multiple Fluid Phases Using X-ray Microtomography

PubMed Central

Andrew, Matthew; Bijeljic, Branko; Blunt, Martin

2015-01-01

X-ray microtomography was used to image, at a resolution of 6.6 µm, the pore-scale arrangement of residual carbon dioxide ganglia in the pore-space of a carbonate rock at pressures and temperatures representative of typical formations used for CO2 storage. Chemical equilibrium between the CO2, brine and rock phases was maintained using a high pressure high temperature reactor, replicating conditions far away from the injection site. Fluid flow was controlled using high pressure high temperature syringe pumps. To maintain representative in-situ conditions within the micro-CT scanner a carbon fiber high pressure micro-CT coreholder was used. Diffusive CO2 exchange across the confining sleeve from the pore-space of the rock to the confining fluid was prevented by surrounding the core with a triple wrap of aluminum foil. Reconstructed brine contrast was modeled using a polychromatic x-ray source, and brine composition was chosen to maximize the three phase contrast between the two fluids and the rock. Flexible flow lines were used to reduce forces on the sample during image acquisition, potentially causing unwanted sample motion, a major shortcoming in previous techniques. An internal thermocouple, placed directly adjacent to the rock core, coupled with an external flexible heating wrap and a PID controller was used to maintain a constant temperature within the flow cell. Substantial amounts of CO2 were trapped, with a residual saturation of 0.203 ± 0.013, and the sizes of larger volume ganglia obey power law distributions, consistent with percolation theory. PMID:25741751

Surface reactivity and hydroxyapatite formation on Ca5MgSi3O12 ceramics in simulated body fluid

NASA Astrophysics Data System (ADS)

Xu, Jian; Wang, Yaorong; Huang, Yanlin; Cheng, Han; Seo, Hyo Jin

2017-11-01

In this work, the new calcium-magnesium-silicate Ca5MgSi3O12 ceramic was made via traditional solid-state reaction. The bioactivities were investigated by immerging the as-made ceramics in simulated body fluid (SBF) for different time at body temperature (37 °C). Then the samples were taken to measure X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), X-ray energy-dispersive spectra (EDS), and Fourier transform infrared spectroscopy (FT-IR) measurements. The bone-like hydroxyapatite nanoparticles formation was observed on the ceramic surfaces after the immersion in SBF solutions. Ca5MgSi3O12 ceramics possess the Young's modulus and the bending strength and of 96.3 ± 1.2 GPa and 98.7 ± 2.3 MPa, respectively. The data suggest that Ca5MgSi3O12 ceramics can quickly induce HA new layers after soaking in SBF. Ca5MgSi3O12 ceramics are potential to be used as biomaterials for bone-tissue repair. The cell adherence and proliferation experiments are conducted confirming the reliability of the ceramics as a potential candidate.

Automated Processing of Plasma Samples for Lipoprotein Separation by Rate-Zonal Ultracentrifugation.

PubMed

Peters, Carl N; Evans, Iain E J

2016-12-01

Plasma lipoproteins are the primary means of lipid transport among tissues. Defining alterations in lipid metabolism is critical to our understanding of disease processes. However, lipoprotein measurement is limited to specialized centers. Preparation for ultracentrifugation involves the formation of complex density gradients that is both laborious and subject to handling errors. We created a fully automated device capable of forming the required gradient. The design has been made freely available for download by the authors. It is inexpensive relative to commercial density gradient formers, which generally create linear gradients unsuitable for rate-zonal ultracentrifugation. The design can easily be modified to suit user requirements and any potential future improvements. Evaluation of the device showed reliable peristaltic pump accuracy and precision for fluid delivery. We also demonstrate accurate fluid layering with reduced mixing at the gradient layers when compared to usual practice by experienced laboratory personnel. Reduction in layer mixing is of critical importance, as it is crucial for reliable lipoprotein separation. The automated device significantly reduces laboratory staff input and reduces the likelihood of error. Overall, this device creates a simple and effective solution to formation of complex density gradients. © 2015 Society for Laboratory Automation and Screening.

Determination of the effect of formation water on fracture-fluid cleanup

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-03-01

Understanding hydraulic-fracture cleanup is essential for improving well stimulation. Residual gel damages fracture conductivity, shortens effective fracture half-length, and limits well productivity. The drive to develop fluids, additives, and procedures that minimize this damage continues to be a dominant theme in fracture-fluid-development programs. Fracture cleanup is a complex problem, and many parameters (e.g., fluid system, job design, flowback procedure, and reservoir conditions) can influence polymer and fluid recovery efficiencies. Often, specific products and methods that work well in one reservoir have little effect in another. Systematic analysis of fluid and polymer returns after a treatment is completed is the onlymore » way to quantify fracture cleanup. This is referred to as flowback analysis. This paper discusses a flowback-analysis field study on large hydraulic-fracturing treatments in the Taylor zone of the Cotton Valley formation in east Texas. This is a low-permeability (approximately 0.01 md) tight gas formation. It is a heterogeneous zone with layers of productive sandstone interspersed with relatively impermeable layers of shale. A typical well in this field initially produces approximately 0.75 to 1.3 MMcf/D gas and 35 to 40 bbl of water/MMcf of gas. The returns from 10 wells in this field were analyzed thoroughly.« less

Altering wettability to recover more oil from tight formations

DOE PAGES

Brady, Patrick V.; Bryan, Charles R.; Thyne, Geoffrey; ...

2016-06-03

We describe here a method for chemically modifying fracturing fluids and overflushes to chemically increase oil recovery from tight formations. Oil wetting of tight formations is usually controlled by adhesion to illite, kerogen, or both; adhesion to carbonate minerals may also play a role. Oil-illite adhesion is sensitive to salinity, dissolved divalent cation content, and pH. We measure oil-rock adhesion with middle Bakken formation oil and core to verify a surface complexation model of reservoir wettability. The agreement between the model and experiments suggests that wettability trends in tight formations can be quantitatively predicted and that fracturing fluid and overflushmore » compositions can be individually tailored to increase oil recovery.« less

Altering wettability to recover more oil from tight formations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, Patrick V.; Bryan, Charles R.; Thyne, Geoffrey

We describe here a method for chemically modifying fracturing fluids and overflushes to chemically increase oil recovery from tight formations. Oil wetting of tight formations is usually controlled by adhesion to illite, kerogen, or both; adhesion to carbonate minerals may also play a role. Oil-illite adhesion is sensitive to salinity, dissolved divalent cation content, and pH. We measure oil-rock adhesion with middle Bakken formation oil and core to verify a surface complexation model of reservoir wettability. The agreement between the model and experiments suggests that wettability trends in tight formations can be quantitatively predicted and that fracturing fluid and overflushmore » compositions can be individually tailored to increase oil recovery.« less

Concentration of adipogenic and proinflammatory cytokines in the bone marrow supernatant fluid of osteoporotic women.

PubMed

Pino, Ana María; Ríos, Susana; Astudillo, Pablo; Fernández, Mireya; Figueroa, Paula; Seitz, Germán; Rodríguez, J Pablo

2010-03-01

Osteoporosis is characterized by low bone mass, microarchitectural deterioration of bone tissue leading to increased bone fragility, and a resulting susceptibility to fractures. Distinctive environmental bone marrow conditions appear to support the development and maintenance of the unbalance between bone resorption and bone formation; these complex bone marrow circumstances would be reflected in the fluid surrounding bone marrow cells. The content of regulatory molecules in the extracellular fluid from the human bone marrow is practically unknown. Since the content of cytokines such as adiponectin, leptin, osteoprogeterin (OPG), soluble receptor activator of nuclear factor kappaB ligand (s-RANKL), tumor necrosis factor alpha, and interleukin 6 (IL-6) may elicit conditions promoting or sustaining osteoporosis, in this work we compared the concentrations of the above-mentioned cytokines and also the level of the soluble receptors for both IL-6 and leptin in the extracellular fluid from the bone marrow of nonosteoporotic and osteoporotic human donors. A supernatant fluid (bone marrow supernatant fluid [BMSF]) was obtained after spinning the aspirated bone marrow samples; donors were classified as nonosteoporotic or osteoporotic after dual-energy X-ray absorptiometry (DXA) measuring. Specific commercially available kits were used for all measurements. The cytokines' concentration in BMSF showed differently among nonosteoporotic and osteoporotic women; this last group was characterized by higher content of proinflammatory and adipogenic cytokines. Also, osteoporotic BMSF differentiated by decreased leptin bioavailability, suggesting that insufficient leptin action may distinguish the osteoporotic bone marrow. Copyright 2010 American Society for Bone and Mineral Research.

Identification of 10 Candidate Biomarkers Distinguishing Tuberculous and Malignant Pleural Fluid by Proteomic Methods.

PubMed

Lee, Chang Youl; Hong, Ji Young; Lee, Myung Goo; Suh, In Bum

2017-11-01

Pleural effusion, an accumulation of fluid in the pleural space, usually occurs in patients when the rate of fluid formation exceeds the rate of fluid removal. The differential diagnosis of tuberculous pleurisy and malignant pleural effusion is a difficult task in high tuberculous prevalence areas. The aim of the present study was to identify novel biomarkers for the diagnosis of pleural fluid using proteomics technology. We used samples from five patients with transudative pleural effusions for internal standard, five patients with tuberculous pleurisy, and the same numbers of patients having malignant effusions were enrolled in the study. We analyzed the proteins in pleural fluid from patients using a technique that combined two-dimensional liquid-phase electrophoresis and matrix assisted laser desorption/ionization-time of flight-mass spectrometry. We identified a total of 10 proteins with statistical significance. Among 10 proteins, trasthyretin, haptoglobin, metastasis-associated protein 1, t-complex protein 1, and fibroblast growth factor-binding protein 1 were related with malignant pleural effusions and human ceruloplasmin, lysozyme precursor, gelsolin, clusterin C complement lysis inhibitor, and peroxirexdoxin 3 were expressed several times or more in tuberculous pleural effusions. Highly expressed proteins in malignant pleural effusion were associated with carcinogenesis and cell growth, and proteins associated with tuberculous pleural effusion played a role in the response to inflammation and fibrosis. These findings will aid in the development of novel diagnostic tools for tuberculous pleurisy and malignant pleural effusion of lung cancer. © Copyright: Yonsei University College of Medicine 2017

Protein-adsorption and Ca-phosphate formation on chitosan-bioactive glass composite coatings

NASA Astrophysics Data System (ADS)

Wagener, V.; Boccaccini, A. R.; Virtanen, S.

2017-09-01

In the last years, chitosan-bioactive glass (BG) composites have been developed and investigated as bioactive coatings for orthopedic applications. The increase of bioactivity occurs due to the stimulation of calcium-phosphate/hydroxyapatite formation on the surface while the coating is degrading. In the present work, protein adsorption and its influence on calcium-phosphate precipitation was studied for the first time on such composite coatings. The experiments involved coating of 316L stainless steel substrates with chitosan (Ch) and chitosan-bioactive glass (Ch-BG) and immersion of the coated samples in two different bovine serum albumin (BSA) containing solutions, namely DI H2O (with pH adjusted to about 7.2 with diluted NaOH) and simulated body fluid (SBF). In order to investigate the influence of protein adsorption on calcium-phosphate precipitation, samples were also immersed in DI H2O and in SBF without BSA. Samples were analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Surface analysis revealed that adsorption of BSA takes place on all studied samples and that protein adsorption is influenced by the presence of Ca2+ and PO43- ions. Bioactivity in the form of hydroxyapatite pre-stage formation is significantly increased on Ch-BG composite coating as compared with bare stainless steel surface. However, calcium-phosphate precipitation in SBF is reduced by the presence of BSA.

Petrophysical laboratory invertigations of carbon dioxide storage in a subsurface saline aquifer in Ketzin/Germany within the scope of CO2SINK

NASA Astrophysics Data System (ADS)

Zemke, K.; Kummmerow, J.; Wandrey, M.; Co2SINK Group

2009-04-01

Since June of 2008 carbon dioxide has been injected into a saline aquifer at the Ketzin test site [Würdemann et al., this volume]. The food grade CO2 is injected into a sandstone zone of the Stuttgart formation at ca. 650 m depth at 35°C reservoir temperature and 62 bar reservoir pressure. With the injection of CO2 into the geological formation, chemical and physical reservoir characteristics are changed depending on pressure, temperature, fluid chemistry and rock composition. Fluid-rock interaction could comprise dissolution of non-resistant minerals in CO2-bearing pore fluids, cementing of the pore space by precipitating substances from the pore fluid, drying and disintegration of clay minerals and thus influence of the composition and activities of the deep biosphere. To testing the injection behaviour of CO2 in water saturated rock and to evaluate the geophysical signature depending on the thermodynamic conditions, flow experiments with water and CO2 have been performed on cores of the Stuttgart formation from different locations including new wells of ketzin test site. The studied core material is an unconsolidated fine-grained sandstone with porosity values from 15 to 32 %. Permeability, electrical resistivity, and sonic wave velocities and their changes with pressure, saturation and time have been studied under simulated in situ conditions. The flow experiments conducted over several weeks with brine and CO2 showed no significant changes of resistivity and velocity and a slightly decreasing permeability. Pore fluid analysis showed mobilization of clay and some other components. A main objective of the CO2Sink laboratory program is the assessment of the effect of long-term CO2 exposure on reservoir rocks to predict the long-term behaviour of geological CO2 storage. For this CO2 exposure experiments reservoir rock samples were exposed to CO2 saturated reservoir fluid in corrosion-resistant high pressure vessels under in situ temperature and pressure conditions over a period of several months. Before and after the CO2 exposure experiment cyclic measurements of physical properties were carried out on these cores in a mechanical testing system. After experimental runs of up to 3 months no significant changes in flow and petrophysical data were observed. [For the microbilogical studies see Wandrey et al., this volume.] To study the impact of fluid-rock interactions on petrophysical parameters, porosity and pore radii distribution have been investigated before and after the experiment by NMR relaxation and mercury-injection. NMR measurements on rock core plugs saturated with brine may return valuable information on the porous structure of the rock core. The distribution of NMR-T2 values (CPMG) reflects the pore sizes within the rock core. NMR pore size is a derivative of the ratio pore surface/volume. The mercury injection pore size is an area-equivalent diameter of the throats connecting the pore system. Most of the tested samples show in the NMR measurements a slightly increasing porosity and a higher part of large pores. The mercury measurements and thin- section for microstructural characterisation after the CO2 exposure will be done at a later date.

Probability of detecting Porcine reproductive and respiratory syndrome virus infection using pen-based swine oral fluid specimens as a function of within-pen prevalence.

PubMed

Olsen, Chris; Wang, Chong; Christopher-Hennings, Jane; Doolittle, Kent; Harmon, Karen M; Abate, Sarah; Kittawornrat, Apisit; Lizano, Sergio; Main, Rodger; Nelson, Eric A; Otterson, Tracy; Panyasing, Yaowalak; Rademacher, Chris; Rauh, Rolf; Shah, Rohan; Zimmerman, Jeffrey

2013-05-01

Pen-based oral fluid sampling has proven to be an efficient method for surveillance of infectious diseases in swine populations. To better interpret diagnostic results, the performance of oral fluid assays (antibody- and nucleic acid-based) must be established for pen-based oral fluid samples. Therefore, the objective of the current study was to determine the probability of detecting Porcine reproductive and respiratory syndrome virus (PRRSV) infection in pen-based oral fluid samples from pens of known PRRSV prevalence. In 1 commercial swine barn, 25 pens were assigned to 1 of 5 levels of PRRSV prevalence (0%, 4%, 12%, 20%, or 36%) by placing a fixed number (0, 1, 3, 5, or 9) of PRRSV-positive pigs (14 days post PRRSV modified live virus vaccination) in each pen. Prior to placement of the vaccinated pigs, 1 oral fluid sample was collected from each pen. Thereafter, 5 oral fluid samples were collected from each pen, for a total of 150 samples. To confirm individual pig PRRSV status, serum samples from the PRRSV-negative pigs (n = 535) and the PRRSV vaccinated pigs (n = 90) were tested for PRRSV antibodies and PRRSV RNA. The 150 pen-based oral fluid samples were assayed for PRRSV antibody and PRRSV RNA at 6 laboratories. Among the 100 samples from pens containing ≥1 positive pig (≥4% prevalence) and tested at the 6 laboratories, the mean positivity was 62% for PRRSV RNA and 61% for PRRSV antibody. These results support the use of pen-based oral fluid sampling for PRRSV surveillance in commercial pig populations.

Liberation of microbial substrates from macromolecular organic matter by non-supercritical CO2

NASA Astrophysics Data System (ADS)

Sauer, P.; Glombitza, C.; Kallmeyer, J.

2012-12-01

The worldwide search for suitable underground storage formations for CO2 also considers coal-bearing strata. CO2 is already injected into coal seams for enhanced recovery of coal bed methane. However, the geochemical and microbiological effects of increased CO2 concentrations on organic matter rich formations are rarely investigated. The injected CO2 will dissolve in the pore water, causing a decrease in pH and resulting in acidic formation waters. Low molecular weight organic acids (LMWOAs) are chemically bound to the macromolecular matrix of sedimentary organic matter and may be liberated by hydrolysis, which is enhanced under acidic conditions. Recent investigations outlined the importance of LMWOAs as a feedstock for subsurface microbial life [1]. Therefore, injection of CO2 into coal formations may result in enhanced nutrient supply for subsurface microbes. To investigate the effects of highly CO2-saturated waters on the release of LMWOAs from coal, we developed an inexpensive high-pressure-high-temperature system that allows manipulating the concentration of dissolved gases up to 60 MPa and 120°C, respectively. The sample is placed in a flexible, gas-tight and inert PVDF sleeve, separating it from the pressure fluid and allowing for subsampling without loss of pressure. Lignite samples from the DEBITS-1 well, Waikato Basin, NZ and the Welzow-Süd open-cast mine, Niederlausitz, Germany, were extracted at 90° C and 5 MPa, with either pure water, CO2-saturated water, CO2/NO2 or CO2/SO2-saturated water. Subsamples were taken at different time points during the 72 hrs. long extraction. Extraction of LMWOAs from coal samples with our pressurised system resulted in yields that were up to four times higher than those reported for Soxhlet extraction [2]. These higher yields may be explained by the fact that during Soxhlet extraction the sample only gets into contact with freshly distilled water, whereas in our system the extraction fluid is circulated, resulting in more acidic extraction conditions. In comparison to pure water extractions, CO2-saturated water affected the extraction yield in both directions by up to 40 percent. For the lignite from DEBITS-1 well, CO2-saturated water resulted in a permanently lower yield, whereas the lignites from the Lausitz showed an increase in formate and a decrease in oxalate. LMWOAs found in the extraction fluid may not just result from hydrolysis but also from different secondary reactions. It was suggested that oxalate in aqueous extracts of coals is a result of the decomposition of 1,2-dihydroxy-carboxylic acids [3]. We assume that for oxalate (and maybe for other LMWOAs as well) the extraction yield is not only affected by hydrolysis but also by secondary reactions, which may be suppressed in the presence of CO2 and other gasses dissolved in the extraction medium. These results show the importance of performing laboratory simulations of subsurface processes under conditions that resemble the true in-situ conditions as closely as possible. References [1] Glombitza et al., 2009, Org. Geochem. 40, 175-183 [2] Vieth et al., 2008, Org. Geochem. 39, 985-991 [3] Bou-Raad et al., 2000, Fuel 79, 1185-1193

Changes in Physical Properties of the Nankai Trough Megasplay Fault Induced by Earthquakes, Detected by Continuous Pressure Monitoring

NASA Astrophysics Data System (ADS)

Kinoshita, C.; Saffer, D.; Kopf, A.; Roesner, A.; Wallace, L. M.; Araki, E.; Kimura, T.; Machida, Y.; Kobayashi, R.; Davis, E.; Toczko, S.; Carr, S.

2018-02-01

One primary objective of Integrated Ocean Drilling Program Expedition 365, conducted as part of the Nankai Trough Seismogenic Zone Experiment, was to recover a temporary observatory emplaced to monitor formation pore fluid pressure and temperature within a splay fault in the Nankai subduction zone offshore SW Honshu, Japan. Here we use a 5.3 year time series of formation pore fluid pressure, and in particular the response to ocean tidal loading, to evaluate changes in pore pressure and formation and fluid elastic properties induced by earthquakes. Our analysis reveals 31 earthquake-induced perturbations. These are dominantly characterized by small transient increases in pressure (28 events) and decreases in ocean tidal loading efficiency (14 events) that reflect changes to formation or fluid compressibility. The observed perturbations follow a magnitude-distance threshold similar to that reported for earthquake-driven hydrological effects in other settings. To explore the mechanisms that cause these changes, we evaluate the expected static and dynamic strains from each earthquake. The expected static strains are too small to explain the observed pressure changes. In contrast, estimated dynamic strains correlate with the magnitude of changes in both pressure and loading efficiency. We propose potential mechanism for the changes and subsequent recovery, which is exsolution of dissolved gas in interstitial fluids in response to shaking.

Experimental and numerical study of hydraulic fracture geometry in shale formations with complex geologic conditions

NASA Astrophysics Data System (ADS)

Ma, Xinfang; Zhou, Tong; Zou, Yushi

2017-05-01

Strike-slip fault geostress and dipping laminated structures in Lujiaping shale formation typically result in difficultly predicting hydraulic fracture (HF) geometries. In this study, a novel 3D fracture propagation model based on discrete element method (DEM) is established. A series of simulations is performed to illustrate the influence of vertical stress difference (△σv = σv-σh), fluid viscosity, and injection rate, on HF growth geometry in the dipping layered formation. Results reveal that the fracturing fluid can easily infiltrate the dipping bedding plane (BP) interfaces with low net pressure for △σv = 1 MPa. HF height growth is also restricted. With increased △σv, fracture propagation in the vertical direction is enhanced, and a fracture network is formed by VF and partially opened dipping BPs. However, it is likely to create simple VF for △σv = 20 MPa. Appropriately increasing fracturing fluid viscosity and injection rate is conductive to weakening the containment effect of BPs on HF growth by increasing the fluid net pressure. However, no indication is found on whether a higher fracturing fluid viscosity is better. Higher viscosity can reduce the activation of BPs, so a stimulated reservoir volume is not necessarily increased. All these results can serve as theoretical guidance for the optimization of fracturing treatments in Lujiaping shale formation.

Chemical compositions and precipitation timing of basement carbonate vein from fossil spreading ridge of South China Sea

NASA Astrophysics Data System (ADS)

Ding, W.; Chen, Y.

2016-12-01

Eighteen calcium carbonate veins within the igneous basement recovered close to the fossil spreading ridge of the South China Sea during the Integrated Ocean Drilling Program (IODP) Expedition 349 were investigated. These carbonates are of primarily either calcite or aragonite, or some mixed aragonite and calcite, with rarely ankerite. The chemical (Ca, Mg, Sr, Mn, Fe) contents and isotopic (87Sr/86Sr, δ18O, δ18C) compositions of the veins were determined to study the evolving chemistry of hydrothermal fluids and to constrain the timing of vein formation. The carbonate δ18O values range from -5.0 to -0.2 ‰ PDB, indicating these are typical low temperature basement carbonates. Chemical analyses show distinct Mg/Ca and Sr/Ca ratios for aragonite and calcite. 87Sr/86Sr ratios show negative correlations with both the depth and δ18O-calculated formation temperature, and are independent of mineralogy with both aragonite and calcite, indicating more geochemically evolved carbonated have precipitated from warmer fluids. The hightest 87Sr/86Sr ratios of vein samples at each drill site are believed to reflect the contemporaneous seawater compositions when carbonates precipitated. No unambiguous precipitation ages can be constrained by correlating 87Sr/86Sr ratios with the global seawater Sr isotope evolution. However, based on correlations of vein chemical composition with depth and formation temperature, as well as the Neogene post-spreading magmatism, we hypothesize 10 Ma is a particular time favoring the formation of carbonate veins in our study area.

Biogeochemical interactions between of coal mine water and gas well cement

NASA Astrophysics Data System (ADS)

Gulliver, D. M.; Gardiner, J. B.; Kutchko, B. G.; Hakala, A.; Spaulding, R.; Tkach, M. K.; Ross, D.

2017-12-01

Unconventional natural gas wells drilled in Northern Appalachia often pass through abandoned coal mines before reaching the Marcellus or Utica formations. Biogeochemical interactions between coal mine waters and gas well cements have the potential to alter the cement and compromise its sealing integrity. This study investigates the mineralogical, geochemical, and microbial changes of cement cores exposed to natural coal mine waters. Static reactors with Class H Portland cement cores and water samples from an abandoned bituminous Pittsburgh coal mine simulated the cement-fluid interactions at relevant temperature for time periods of 1, 2, 4, and 6 weeks. Fluids were analyzed for cation and anion concentrations and extracted DNA was analyzed by 16S rRNA gene sequencing and shotgun sequencing. Cement core material was evaluated via scanning electron microscope. Results suggest that the sampled coal mine water altered the permeability and matrix mineralogy of the cement cores. Scanning electron microscope images display an increase in mineral precipitates inside the cement matrix over the course of the experiment. Chemistry results from the reaction vessels' effluent waters display decreases in dissolved calcium, iron, silica, chloride, and sulfate. The microbial community decreased in diversity over the 6-week experiment, with Hydrogenophaga emerging as dominant. These results provide insight in the complex microbial-fluid-mineral interactions of these environments. This study begins to characterize the rarely documented biogeochemical impacts that coal waters may have on unconventional gas well integrity.

Contrasting serpentinization processes in the eastern Central Alps

USGS Publications Warehouse

Burkhard, D.J.M.; O'Neil, J.R.

1988-01-01

Stable isotope compositions have been determined for serpentinites from between Davos (Arosa-Platta nappe, Switzerland) and the Valmalenco (Italy). ??D and ??18O values (-120 to -60 and 6-10???, respectively) in the Arosa-Platta nappe indicate that serpentinization took place on the continent at relatively low temperatures in the presence of limited amounts of metamorphic fluids that contained a component of meteoric water. One sample of chrysotile has a ??18O value of 13??? providing evidence of high W/R ratios and low formation temperature of lizardite-chrysotile in this area. In contrast, relatively high ??D values (-42 to -34???) and low ??18O values (4.4-7.4???) for serpentine in the eastern part of the Valmalenco suggest a serpentinization process that took place at moderate temperatures in fluids that were dominated by ocean water. The antigorite in the Valmalenco is the first reported example of continental antigorite with an ocean water signature. An amphibole sample from a metasomatically overprinted contact zone to metasediments (??D=-36???) indicates that the metasomatic event also took place in the presence of ocean water. Lower ??D values (-93 to -60???) of serpentines in the western part of the Valmalenco suggest a different alteration history possibly influenced by fluids associated with contact metamorphism. Low water/rock ratios during regional metamorphism (and metasomatism) have to be assumed for both regions. ?? 1988 Springer-Verlag.

Contrasting serpentinization processes in the eastern Central Alps

NASA Astrophysics Data System (ADS)

Burkhard, Dorothee J. M.; O'Neil, James R.

1988-08-01

Stable isotope compositions have been determined for serpentinites from between Davos (Arosa-Platta nappe, Switzerland) and the Valmalenco (Italy). δD and δ 18O values (-120 to -60 and 6 10‰, respectively) in the Arosa-Platta nappe indicate that serpentinization took place on the continent at relatively low temperatures in the presence of limited amounts of metamorphic fluids that contained a component of meteoric water. One sample of chrysotile has a δ 18O value of 13‰ providing evidence of high W/R ratios and low formation temperature of lizardite-chrysotile in this area. In contrast, relatively high δD values (-42 to -34‰) and low δ 18O values (4.4 7.4‰) for serpentine in the eastern part of the Valmalenco suggest a serpentinization process that took place at moderate temperatures in fluids that were dominated by ocean water. The antigorite in the Valmalenco is the first reported example of continental antigorite with an ocean water signature. An amphibole sample from a metasomatically overprinted contact zone to metasediments ( δD=-36‰) indicates that the metasomatic event also took place in the presence of ocean water. Lower δD values (-93 to -60‰) of serpentines in the western part of the Valmalenco suggest a different alteration history possibly influenced by fluids associated with contact metamorphism. Low water/rock ratios during regional metamorphism (and metasomatism) have to be assumed for both regions.

Subsurface conditions in hydrothermal vents inferred from diffuse flow composition, and models of reaction and transport

NASA Astrophysics Data System (ADS)

Larson, B. I.; Houghton, J. L.; Lowell, R. P.; Farough, A.; Meile, C. D.

2015-08-01

Chemical gradients in the subsurface of mid-ocean ridge hydrothermal systems create an environment where minerals precipitate and dissolve and where chemosynthetic organisms thrive. However, owing to the lack of easy access to the subsurface, robust knowledge of the nature and extent of chemical transformations remains elusive. Here, we combine measurements of vent fluid chemistry with geochemical and transport modeling to give new insights into the under-sampled subsurface. Temperature-composition relationships from a geochemical mixing model are superimposed on the subsurface temperature distribution determined using a heat flow model to estimate the spatial distribution of fluid composition. We then estimate the distribution of Gibb's free energies of reaction beneath mid oceanic ridges and by combining flow simulations with speciation calculations estimate anhydrite deposition rates. Applied to vent endmembers observed at the fast spreading ridge at the East Pacific Rise, our results suggest that sealing times due to anhydrite formation are longer than the typical time between tectonic and magmatic events. The chemical composition of the neighboring low temperature flow indicates relatively uniform energetically favorable conditions for commonly inferred microbial processes such as methanogenesis, sulfate reduction and numerous oxidation reactions, suggesting that factors other than energy availability may control subsurface microbial biomass distribution. Thus, these model simulations complement fluid-sample datasets from surface venting and help infer the chemical distribution and transformations in subsurface flow.

Characterizing Microbial Diversity and Function in Natural Subsurface CO2 Reservoir Systems for Applied Use in Geologic Carbon Sequestration Environments

NASA Astrophysics Data System (ADS)

Freedman, A.; Thompson, J. R.

2013-12-01

The injection of CO2 into geological formations at quantities necessary to significantly reduce CO2 emissions will represent an environmental perturbation on a continental scale. The extent to which biological processes may play a role in the fate and transport of CO2 injected into geological formations has remained an open question due to the fact that at temperatures and pressures associated with reservoirs targeted for sequestration CO2 exists as a supercritical fluid (scCO2), which has generally been regarded as a sterilizing agent. Natural subsurface accumulations of CO2 serve as an excellent analogue for studying the long-term effects, implications and benefits of CO2 capture and storage (CCS). While several geologic formations bearing significant volumes of nearly pure scCO2 phases have been identified in the western United States, no study has attempted to characterize the microbial community present in these systems. Because the CO2 in the region is thought to have first accumulated millions of years ago, it is reasonable to assume that native microbial populations have undergone extensive and unique physiological and behavioral adaptations to adjust to the exceedingly high scCO2 content. Our study focuses on the microbial communities associated with the dolomite limestone McElmo Dome scCO2 Field in the Colorado Plateau region, approximately 1,000 m below the surface. Fluid samples were collected from 10 wells at an industrial CO2 production facility outside Cortez, CO. Subsamples preserved on site in 3.7% formaldehyde were treated in the lab with Syto 9 green-fluorescent nucleic acid stain, revealing 3.2E6 to 1.4E8 microbial cells per liter of produced fluid and 8.0E9 cells per liter of local pond water used in well drilling fluids. Extracted DNAs from sterivex 0.22 um filters containing 20 L of sample biomass were used as templates for PCR targeting the 16S rRNA gene. 16S rRNA amplicons from these samples were cloned, sequenced and subjected to microbial community analysis to test the hypothesis that a low but non-zero diversity that includes taxa from other subsurface environments will be present, reflecting the extreme ecological selective pressures of scCO2. A wide range of phylogenies have been identified, including genera that fall within the Proteobacteria, Bacilli, and Clostridial classes. Several species identified by 16S BLAST best hits are also known to inhabit deep subsurface environments, preliminarily confirming that a non-zero diversity has been able to survive, and possibly thrive, in the extreme scCO2-exposed deep subsurface environment at McElmo Dome. It thus appears that at least a subsection of native subsurface community biota may withstand the severe stresses associated with the injection of scCO2 for long-term geologic carbon sequestration efforts.

Isotopic fractionation of nitrogen and carbon in Paleoarchean cherts from Pilbara craton, Western Australia: Origin of 15N-depleted nitrogen

NASA Astrophysics Data System (ADS)

Pinti, Daniele L.; Hashizume, Ko; Sugihara, Akiyo; Massault, Marc; Philippot, Pascal

2009-07-01

Nitrogen and carbon isotopic compositions, together with mineralogy and trace element geochemistry, were studied in a few kerogen-rich Paleoarchean cherts, a barite and a dolomitic stromatolite belonging to the eastern (Dixon Island Formation) and western (Dresser and Strelley Pool Chert Formations; North Pole Dome and Marble Bar) terranes of Pilbara Craton, Western Australia. The aim of the study was to search for 15N-depleted isotopic signatures, often found in kerogens of this period, and explain the origin of these anomalies. Trace elements suggest silica precipitation by hydrothermal fluids as the main process of chert formation with a contamination from volcanoclastic detritus. This is supported by the occurrence of hydrothermal-derived minerals in the studied samples indicating precipitation temperatures up to 350 °C. Only a dolomitic stromatolite from Strelley Pool shows a superchondritic Y/Ho ratio of 72 and a positive Eu/Eu * anomaly of 1.8, characteristic of chemical precipitates from the Archean seawater. The bulk δ 13C vs. δ 15N values measured in the cherts show a roughly positive co-variation, except for one sample from the North Pole (PI-85-00). The progressive enrichment in 15N and 13C from a pristine source having δ 13C ⩽ -36‰ and δ 15N ⩽ -4‰ is correlated with a progressive depletion in N content and to variations in Ba/La and Co/As ratios. These trends have been interpreted as a progressive hydrothermal alteration of the cherts by metamorphic fluids. Isotopic exchange at 350 °C between NH 4+(rock) and N 2(fluid) may explain the isotopic and elemental composition of N in the studied cherts. However, we need to assume isotopic exchange at 350 °C between carbonate C and graphite to explain the large 13C enrichment recorded. Only sample PI-85-00 shows a large N loss (90%) with a positive δ 15N value (+11‰), while C (up to 120 ppm and δ 13C -38‰) seems to be unaffected. This pattern has been interpreted as the result of devolatilization and alteration (oxidation) of graphite by low-temperature fluids. The 15N- 13C-depleted pristine source has δ 15N values from -7‰ to -4‰ and 40Ar/ 36Ar ratios from 30,000 to 60,000, compatible with an inorganic mantle N source, although the elemental abundance ratios N/C and 40Ar/C are not exactly the same with the mantle source. The component alternatively could be explained by elemental fractionation from metabolic activity of chemolithoautotrophs and methanogens at the proximity to the hydrothermal vents. However, ambiguities between mantle vs organic sources of N subsist and need further experimental work to be fully elucidated.

Barite-forming environments along a rifted continental margin, Southern California Borderland

USGS Publications Warehouse

Hein, James R.; Zierenberg, Robert A.; Maynard, J. Barry; Hannington, Mark D.

2007-01-01

The Southern California Continental Borderland (SCCB) is part of the broad San Andreas transform-fault plate boundary that consists of a series of fault-bounded, petroleum-generating basins. The SCCB has high heat flow and geothermal gradients produced by thinned continental crust and Neogene volcanism. Barite deposits in the SCCB occur along faults. Barite samples from two sea-cliff sites and four offshore sites in the SCCB were analyzed for mineralogy, chemical (54 elements) and isotopic (S, Sr) compositions, and petrography. Barite from Palos Verdes (PV) Peninsula sea-cliff outcrops is hosted by the Miocene Monterey Formation and underlying basalt; carbonate rocks from those outcrops were analyzed for C, O, and Sr isotopes and the basalt for S isotopes. Cold-seep barite from Monterey Bay, California was analyzed for comparison. SCCB offshore samples occur at water depths from about 500 to 1800 m. Those barites vary significantly in texture and occurrence, from friable, highly porous actively growing seafloor mounds to dense, brecciated, vein barite. This latter type of barite contrasts with cold-seep barite in being much more coarse grained, forms thick veins in places, and completely replaced rock clasts in breccia. The barite samples range from 94 to 99 wt% BaSO4, with low trace-element contents, except for high Sr, Zr, Br, U, and Hg concentrations compared to their crustal abundances. δ34S for SCCB offshore barites range from 21.6‰ to 67.4‰, and for PV barite from 62‰ to 70‰. Pyrite from PV sea-cliff basalt and sedimentary rocks that host the barites averages 7.8‰ and 2.2‰, respectively. Two offshore barite samples have δ34S values (21.6‰, 22.1‰) close to that of modern seawater sulfate, whereas all other samples are enriched to strongly enriched in 34S. 87Sr/86Sr ratios for the barites vary over a narrow range of 0.70830–0.70856 and are much lower than that of modern seawater and also lower than the middle Miocene seawater ratio, the time of deposition of the host rocks for the PV samples. This indicates that the mineralizing fluids were not unaltered seawater. We develop a model in which the barites precipitated both below the sediment–water interface and at the seafloor from low-temperature fluids that circulated along faults. The isotopic, chemical, and textural data indicate that the barites formed by several processes. Mesozoic and Cenozoic basement rocks (crystalline and overlying sedimentary rocks), Quaternary basin fill, turbidite fans, and seawater provided various elements for the barites in different environments. The fluids had a deep-seated source and were hydrothermal in the deeper parts of the system for all the barite types, including the seafloor cold-seep deposit, based on Sr isotopes and regional geothermal gradients. These deep-seated fluids mixed with other fluids as they ascended, including seawater at and near the seafloor. The high δ34S values may have resulted from extreme Rayleigh fractionation during bacterially mediated (semi)closed-system sulfate reduction, probably driven by the flux of methane- and hydrocarbon-bearing fluids through basement rocks and basin sediments. Early diagenetic dolomite and pyrite in the host Monterey Formation in the PV Headland also formed in a zone of sulfate reduction, but within sediment buried only centimeters to a few meters and with a predominantly seawater source for the sulfur. Dolomite occurring with vein barite in the PV Headland formed at temperatures in the range of 40–90 °C. The cold-seep barites have δ34S values near that of modern seawater, although still somewhat fractionated. The barites that precipitated below the sediment–water interface have higher δ34S values, suggesting that the fluids were relatively reduced with molar dissolved barium in excess of dissolved sulfate. Those samples were exposed at the seafloor by uplift along faults and are composed predominantly of massive, brecciated, and vein barite.

Low temperature barrier wellbores formed using water flushing

DOEpatents

McKinzie, II; John, Billy [Houston, TX; Keltner, Thomas Joseph [Spring, TX

2009-03-10

A method of forming an opening for a low temperature well is described. The method includes drilling an opening in a formation. Water is introduced into the opening to displace drilling fluid or indigenous gas in the formation adjacent to a portion of the opening. Water is produced from the opening. A low temperature fluid is applied to the opening.

Convectively driven PCR thermal-cycling

DOEpatents

Benett, William J.; Richards, James B.; Milanovich, Fred P.

2003-07-01

A polymerase chain reaction system provides an upper temperature zone and a lower temperature zone in a fluid sample. Channels set up convection cells in the fluid sample and move the fluid sample repeatedly through the upper and lower temperature zone creating thermal cycling.

Multicomponent analysis of radiolytic products in human body fluids using high field proton nuclear magnetic resonance (NMR) spectroscopy

NASA Astrophysics Data System (ADS)

Grootveld, Martin C.; Herz, Herman; Haywood, Rachel; Hawkes, Geoffrey E.; Naughton, Declan; Perera, Anusha; Knappitt, Jacky; Blake, David R.; Claxson, Andrew W. D.

1994-05-01

High field proton Hahn spin-echo nuclear magnetic resonance (NMR) spectroscopy has been employed to investigate radiolytic damage to biomolecules present in intact human body fluids. γ-Radiolysis of healthy or rheumatoid human serum (5.00 kGy) in the presence of atmospheric O 2 gave rise to reproducible elevations in the concentration of NMR-detectable acetate which are predominantly ascribable to the prior oxidation of lactate to pyruvate by hydroxyl radical (·OH) followed by oxidative decarboxylation of pyruvate by radiolytically-generated hydrogen peroxide (H 2O 2) and/or further ·OH radical. Increases in the serum levels of non-protein-bound, low-molecular-mass components such as citrate and glutamine were also observed subsequent to γ-radiolysis, an observation which may reflect their mobilisation from protein binding-sites by ·OH radical, superoxide anion and/or H 2O 2. Moreover, substantial radiolytically-mediated elevations in the concentration of serum formate were also detectable. In addition to the above modifications, γ-radiolysis of inflammatory knee-joint synovial fluid (SF) generated a low-molecular-mass oligosaccharide species derived from the radiolytic fragmentation of hyaluronate. The radiolytically-mediated production of acetate in SF samples was markedly greater than that observed in serum samples, a consequence of the much higher levels of ·OH radical-scavenging lactate present. Indeed, increases in SF acetate concentration were detectable at doses as low as 48 Gy. We conclude that high field proton NMR analysis provides much useful information regarding the relative radioprotectant abilities of endogenous components and the nature, status and levels of radiolytic products generated in intact biofluids. We also suggest that NMR-detectable radiolytic products with associated toxicological properties (e.g. formate) may play a role in contributing to the deleterious effects observed following exposure of living organisms to sources of ionising radiation.

On the matter of synovial fluid lubrication: implications for Metal-on-Metal hip tribology.

PubMed

Myant, Connor; Cann, Philippa

2014-06-01

Artificial articular joints present an interesting, and difficult, tribological problem. These bearing contacts undergo complex transient loading and multi axes kinematic cycles, over extremely long periods of time (>10 years). Despite extensive research, wear of the bearing surfaces, particularly metal-metal hips, remains a major problem. Comparatively little is known about the prevailing lubrication mechanism in artificial joints which is a serious gap in our knowledge as this determines film formation and hence wear. In this paper we review the accepted lubrication models for artificial hips and present a new concept to explain film formation with synovial fluid. This model, recently proposed by the authors, suggests that interfacial film formation is determined by rheological changes local to the contact and is driven by aggregation of synovial fluid proteins. The implications of this new mechanism for the tribological performance of new implant designs and the effect of patient synovial fluid properties are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microfluidics apparatus and methods for use thereof

DOEpatents

Peeters, John P.; Wiggins, Thomas; Ghosh, Madhushree; Bottomley, Lawrence A.; Seminara, Salvatore; Hu, Zhiyu; Seeley, Timothy; Kossek, Sebastian

2005-08-09

A microfluidics device includes a plurality of interaction cells and fluid control means including i) means for providing to the interaction cells a preparation fluid, and ii) means for providing to the interaction cells a sample fluid, wherein each interaction cell receives a different sample fluid. A plurality of microcantilevers may be disposed in each of the interaction cells, wherein each of the plurality of microcantilevers configured to deflect in response to an interaction involving a component of the sample fluid.

The Influence of Grain Boundary Fluids on the Recrystallization Behavior in Calcite: A Comparison of "dry" and "wet" Marble Mylonites

NASA Astrophysics Data System (ADS)

Schenk, O.; Urai, J.; Evans, B.

2003-12-01

Carbonate rocks are able to accumulate large amounts of strain and deform crystal-plastically even at low p-T conditions and thus, marble sequences are often the site of strain localization in the upper crust during late-stage deformation in mountain building processes. In this study we sought to identify the effect of fluids on grain boundary morphology and recrystallization processes in marble mylonites during shear zone evolution, as fluids play a major role in the flow behavior of many rock materials during deformation (e.g. quartz, olivine, halite, feldspar). We compared calcite marble mylonites from two geological settings: (a) Schneeberg Complex, Southern Tyrole, Italy and (b) Naxos Metamorphic Core Complex, Greece. The shear zones of the selected areas are suitable for comparison, because they consist of similar lithology and the marble mylonites resemble each other in chemical composition. In addition, calcite-dolomite solvus geothermometry and TEM observations indicate similar p-T conditions for the shear zones formation. However, the two settings are different in the availability of fluids during the shear zone evolution: In the Schneeberg mylonites, both the alteration of minerals during retrograde metamorphism of neighboring micaschists and the existence of veins suggest that fluids were present during mylonitization. The absence of these features in the Naxos samples indicates that fluids were not present during deformation of these mylonites. This difference is also supported by the signature of stable isotopes. Microstructural investigations using optical and scanning electron microscopes on broken and planar surfaces did not indicate major differences between wet and dry mylonites: Grain boundaries of both types of samples display pores with shapes controlled by crystallography, and pore morphologies that are similar to observations from crack and grain-boundary healing experiments. Grain size reduction was predominantly the result of subgrain rotation recrystallization. However, the coarse grains inside the wet protomylonites (Schneeberg) are characterized by intracrystalline shear zones. With the exception of the intracrystalline shear zones, there were no obvious microstructural signatures that were obvious indicators of the presence of fluids, at least for these two field examples.

Carbon isotope fractionation during diamond growth in depleted peridotite: Counterintuitive insights from modelling water-maximum CHO fluids as multi-component systems

NASA Astrophysics Data System (ADS)

Stachel, T.; Chacko, T.; Luth, R. W.

2017-09-01

Because of the inability of depleted cratonic peridotites to effectively buffer oxygen fugacities when infiltrated by CHO or carbonatitic fluids, it has been proposed recently (Luth and Stachel, 2014) that diamond formation in peridotites typically does not occur by rock-buffered redox reactions as previously thought but by an oxygen-conserving reaction in which minor coexisting CH4 and CO2 components in a water-rich fluid react to form diamond (CO2 + CH4 = 2C + 2H2O). In such fluid-buffered systems, carbon isotope fractionation during diamond precipitation occurs in the presence of two dominant fluid carbon species. Carbon isotope modelling of diamond precipitation from mixed CH4- and CO2-bearing fluids reveals unexpected fundamental differences relative to diamond crystallization from a single carbon fluid species: (1) irrespective of which carbon fluid species (CH4 or CO2) is dominant in the initial fluid, diamond formation is invariably associated with progressive minor (<1‰) enrichment of diamond in 13C as crystallization proceeds. This is in contrast to diamond precipitation by rock-buffered redox processes from a fluid containing only a single carbon species, which can result in either progressive 13C enrichment (CO2 or carbonate fluids) or 13C depletion (CH4 fluids) in the diamond. (2) Fluid speciation is the key factor controlling diamond δ13 C values; as XCO2 (XCO2 = CO2/[CO2 + CH4]) in the initial fluid increases from 0.1 to 0.9 (corresponding to an increase in fO2 of 0.8 log units), the carbon isotope composition of the first-precipitated diamond decreases by 3.7‰. The tight mode in δ13C of - 5 ± 1 ‰ for diamonds worldwide places strict constraints on the dominant range of XCO2 in water-rich fluids responsible for diamond formation. Specifically, precipitation of diamonds with δ13C values in the range -4 to -6‰ from mantle-derived fluids with an average δ13C value of -5‰ (derived from evidence not related to diamonds) requires that diamond-forming fluids were relatively reduced and had methane as the dominant carbon species (XCO2 = 0.1-0.5). Application of our model to a recently published set of in-situ carbon isotope analyses for peridotitic diamonds from Marange, Zimbabwe (Smit et al., 2016), which contain CH4 fluid inclusions, allows us to perfectly match the observed co-variations in δ13 C, δ15 N and N content and at the same time explain the previously counter-intuitive observation of progressive 13C enrichment in diamonds that appear to have grown from a fluid with methane as the dominant carbon species. Similarly, the almost complete absence in the published record of progressive 13C depletion trends within diamonds likely reflects ubiquitous precipitation from CH4- and CO2-bearing water-rich fluids, rather than diamond formation exclusively by carbonate-bearing and CH4-free oxidized fluids or melts.

A 3-D wellbore simulator (WELLTHER-SIM) to determine the thermal diffusivity of rock-formations

NASA Astrophysics Data System (ADS)

Wong-Loya, J. A.; Santoyo, E.; Andaverde, J.

2017-06-01

Acquiring thermophysical properties of rock-formations in geothermal systems is an essential task required for the well drilling and completion. Wellbore thermal simulators require such properties for predicting the thermal behavior of a wellbore and the formation under drilling and shut-in conditions. The estimation of static formation temperatures also needs the use of these properties for the wellbore and formation materials (drilling fluids and pipes, cements, casings, and rocks). A numerical simulator (WELLTHER-SIM) has been developed for modeling the drilling fluid circulation and shut-in processes of geothermal wellbores, and for the in-situ determination of thermal diffusivities of rocks. Bottomhole temperatures logged under shut-in conditions (BHTm), and thermophysical and transport properties of drilling fluids were used as main input data. To model the thermal disturbance and recovery processes in the wellbore and rock-formation, initial drilling fluid and static formation temperatures were used as initial and boundary conditions. WELLTHER-SIM uses these temperatures together with an initial thermal diffusivity for the rock-formation to solve the governing equations of the heat transfer model. WELLTHER-SIM was programmed using the finite volume technique to solve the heat conduction equations under 3-D and transient conditions. Thermal diffusivities of rock-formations were inversely computed by using an iterative and efficient numerical simulation, where simulated thermal recovery data sets (BHTs) were statistically compared with those temperature measurements (BHTm) logged in some geothermal wellbores. The simulator was validated using a well-documented case reported in the literature, where the thermophysical properties of the rock-formation are known with accuracy. The new numerical simulator has been successfully applied to two wellbores drilled in geothermal fields of Japan and Mexico. Details of the physical conceptual model, the numerical algorithm, and the validation and application results are outlined in this work.

Fluids in Convergent Margins: What do We Know about their Composition, Origin, Role in Diagenesis and Importance for Oceanic Chemical Fluxes?

NASA Astrophysics Data System (ADS)

Kastner, M.; Elderfield, H.; Martin, J. B.

1991-05-01

The nature and origin of fluids in convergent margins can be inferred from geochemical and isotopic studies of the venting and pore fluids, and is attempted here for the Barbados Ridge, Nankai Trough and the convergent margin off Peru. Venting and pore fluids with lower than seawater Cl- concentrations characterize all these margins. Fluids have two types of source: internal and external. The three most important internal sources are: (1) porosity reduction; (2) diagenetic and metamorphic dehydration; and (3) the breakdown of hydrous minerals. Gas hydrate formation and dissociation, authigenesis of hydrous minerals and the alteration of volcanic ash and/or the upper oceanic crust lead to a redistribution of the internal fluids and gases in vertical and lateral directions. The maximum amount of expelled water calculated can be ca. 7 m3 a-1 m-1, which is much less than the tens to more than 100 m3 a-1 m-1 of fluid expulsion which has been observed. The difference between these figures must be attributed to external fluid sources, mainly by transport of meteoric water enhanced by mixing with seawater. The most important diagenetic reactions which modify the fluid compositions, and concurrently the physical and even the thermal properties of the solids through which they flow are: (1) carbonate recrystallization, and more importantly precipitation; (2) bacterial and thermal degradation of organic matter; (3) formation and dissociation of gas hydrates; (4) dehydration and transformation of hydrous minerals, especially of clay minerals and opal-A; and (5) alteration, principally zeolitization and clay mineral formation, of volcanic ash and the upper oceanic crust.

A Numerical Study of Factors Affecting Fracture-Fluid Cleanup and Produced Gas/Water in Marcellus Shale: Part II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seales, Maxian B.; Dilmore, Robert; Ertekin, Turgay

Horizontal wells combined with successful multi-stage hydraulic fracture treatments are currently the most established method for effectively stimulating and enabling economic development of gas bearing organic-rich shale formations. Fracture cleanup in the Stimulated Reservoir Volume (SRV) is critical to stimulation effectiveness and long-term well performance. However, fluid cleanup is often hampered by formation damage, and post-fracture well performance frequently falls below expectations. A systematic study of the factors that hinder fracture fluid cleanup in shale formations can help optimize fracture treatments and better quantify long term volumes of produced water and gas. Fracture fluid cleanup is a complex process influencedmore » by multi-phase flow through porous media (relative permeability hysteresis, capillary pressure etc.), reservoir rock and fluid properties, fracture fluid properties, proppant placement, fracture treatment parameters, and subsequent flowback and field operations. Changing SRV and fracture conductivity as production progresses further adds to the complexity of this problem. Numerical simulation is the best, and most practical approach to investigate such a complicated blend of mechanisms, parameters, their interactions, and subsequent impact on fracture fluid cleanup and well deliverability. In this paper, a 3-dimensional, 2-phase, dual-porosity model was used to investigate the impact of multiphase flow, proppant crushing, proppant diagenesis, shut-in time, reservoir rock compaction, gas slippage, and gas desorption on fracture fluid cleanup, and well performance in Marcellus shale. The research findings have shed light on the factors that substantially constrains efficient fracture fluid cleanup in gas shales, and provided guidelines for improved fracture treatment designs and water management.« less

DOE workshop: Sedimentary systems, aqueous and organic geochemistry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-07-01

A DOE workshop on sedimentary systems, aqueous and organic geochemistry was held July 15-16, 1993 at Lawrence Berkeley Laboratory. Papers were organized into several sections: Fundamental Properties, containing papers on the thermodynamics of brines, minerals and aqueous electrolyte solutions; Geochemical Transport, covering 3-D imaging of drill core samples, hydrothermal geochemistry, chemical interactions in hydrocarbon reservoirs, fluid flow model application, among others; Rock-Water Interactions, with presentations on stable isotope systematics of fluid/rock interaction, fluid flow and petotectonic evolution, grain boundary transport, sulfur incorporation, tracers in geologic reservoirs, geothermal controls on oil-reservoir evolution, and mineral hydrolysis kinetics; Organic Geochemistry covered new methodsmore » for constraining time of hydrocarbon migration, kinetic models of petroleum formation, mudstones in burial diagenesis, compound-specific carbon isotope analysis of petroleums, stability of natural gas, sulfur in sedimentary organic matter, organic geochemistry of deep ocean sediments, direct speciation of metal by optical spectroscopies; and lastly, Sedimentary Systems, covering sequence stratigraphy, seismic reflectors and diagenetic changes in carbonates, geochemistry and origin of regional dolomites, and evidence of large comet or asteroid impacts at extinction boundaries.« less

Marble-hosted ruby deposits of the Morogoro Region, Tanzania

NASA Astrophysics Data System (ADS)

Balmer, Walter A.; Hauzenberger, Christoph A.; Fritz, Harald; Sutthirat, Chakkaphan

2017-10-01

The ruby deposits of the Uluguru and Mahenge Mts, Morogoro Region, are related to marbles which represent the cover sequence of the Eastern Granulites in Tanzania. In both localities the cover sequences define a tectonic unit which is present as a nappe structure thrusted onto the gneissic basement in a north-western direction. Based on structural geological observations the ruby deposits are bound to mica-rich boudins in fold hinges where fluids interacted with the marble-host rock in zones of higher permeability. Petrographic observations revealed that the Uluguru Mts deposits occur within calcite-dominated marbles whereas deposits in the Mahenge Mts are found in dolomite-dominated marbles. The mineral assemblage describing the marble-hosted ruby deposit in the Uluguru Mts is characterised by corundum-dolomite-phlogopite ± spinel, calcite, pargasite, scapolite, plagioclase, margarite, chlorite, tourmaline whereas the assemblage corundum-calcite-plagioclase-phlogopite ± dolomite, pargasite, sapphirine, titanite, tourmaline is present in samples from the Mahenge Mts. Although slightly different in mineral assemblage it was possible to draw a similar ruby formation history for both localities. Two ruby forming events were distinguished by textural differences, which could also be modeled by thermodynamic T-XCO2 calculations using non-ideal mixing models of essential minerals. A first formation of ruby appears to have taken place during the prograde path (M1) either by the breakdown of diaspore which was present in the original sedimentary precursor rock or by the breakdown of margarite to corundum and plagioclase. The conditions for M1 metamorphism was estimated at ∼750 °C at 10 kbar, which represents granulite facies conditions. A change in fluid composition towards a CO2 dominated fluid triggered a second ruby generation to form. Subsequently, the examined units underwent a late greenschist facies overprint. In the framework of the East African Orogen we assume that the prograde ruby formation occurred at the commonly observed metamorphic event around 620 Ma. At the peak or during beginning of retrogression the fluid composition changed triggering a second ruby generation. The late stage greenschist facies overprint could have occurred at the waning stage of this metamorphic episode which is in the range of ∼580 Ma.

Formation of the Periotic Space During the Early Fetal Period in Humans.

PubMed

Ishikawa, Aoi; Ohtsuki, Sae; Yamada, Shigehito; Uwabe, Chigako; Imai, Hirohiko; Matsuda, Tetsuya; Takakuwa, Tetsuya

2018-04-01

The inner ear is a very complicated structure, composed of a bony labyrinth (otic capsule; OC), membranous labyrinth, with a space between them, named the periotic labyrinth or periotic space. We investigated how periotic tissue fluid spaces covered the membranous labyrinth three-dimensionally, leading to formation of the periotic labyrinth encapsulated in the OC during human fetal development. Digital data sets from magnetic resonance images and phase-contrast X-ray tomography images of 24 inner ear organs from 24 human fetuses from the Kyoto Collection (fetuses in trimesters 1 and 2; crown-rump length: 14.4-197 mm) were analyzed. The membranous labyrinth was morphologically differentiated in samples at the end of the embryonic period (Carnegie stage 23), and had grown linearly to more than eight times in size during the observation period. The periotic space was first detected at the 35-mm samples, around the vestibule and basal turn of the cochlea, which elongated rapidly to the tip of the cochlea and semicircular ducts, successively, and almost covered the membranous labyrinth at the 115-mm CRL stage or later. In those samples, several ossification centers were detected around the space. This article thus demonstrated that formation of the membranous labyrinth, periotic space (labyrinth), and ossification of the OC occurs successively, according to an intricate timetable. Anat Rec, 301:563-570, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Fluid Mechanics and Heat Transfer in Transitional Boundary Layers

NASA Technical Reports Server (NTRS)

Wang, Ting

2007-01-01

Experiments have been performed to investigate the effects of elevated free-stream turbulence and streamwise acceleration on flow and thermal structures in transitional boundary layers. The free-stream turbulence ranges from 0.5 to 6.4% and the streamwise acceleration ranges from K = 0 to 0.8 x 10(exp -6). The onset of transition, transition length and the turbulent spot formation rate are determined. The statistical results and conditionally sampled results of th streamwise and cross-stream velocity fluctuations, temperature fluctuations, Reynolds stress and Reynolds heat fluxes are presented.

Study the formation of porous surface layer for a new biomedical titanium alloy

NASA Astrophysics Data System (ADS)

Talib Mohammed, Mohsin; Diwan, Abass Ali; Ali, Osamah Ihsan

2018-03-01

In the present work, chemical treatment using hydrogen peroxide (H2O2) oxidation and subsequent thermal treatment was applied to create a uniform porous layer over the surface of a new metastable β-Ti alloy. The results revealed that this oxidation treatment can create a stable ultrafine porous film over the oxidized surface. This promoted the electrochemical characteristics of H2O2-treated Ti-Zr-Nb (TZN) alloy system, presenting nobler corrosion behavior in simulated body fluid (SBF) comparing with untreated sample.

Fluid Flow Characteristics and Porosity Behavior in Full Penetration Laser Welding of a Titanium Alloy

NASA Astrophysics Data System (ADS)

Chang, Baohua; Allen, Chris; Blackburn, Jon; Hilton, Paul; Du, Dong

2015-04-01

In this paper, a computational fluid mechanics model is developed for full penetration laser welding of titanium alloy Ti6Al4V. This has been used to analyze possible porosity formation mechanisms, based on predictions of keyhole behavior and fluid flow characteristics in the weld pool. Numerical results show that when laser welding 3 mm thickness titanium alloy sheets with given laser beam focusing optics, keyhole depth oscillates before a full penetration keyhole is formed, but thereafter keyhole collapses are not predicted numerically. For lower power, lower speed welding, the fluid flow behind the keyhole is turbulent and unstable, and vortices are formed. Molten metal is predicted to flow away from the center plane of the weld pool, and leave a gap or void within the weld pool behind the keyhole. For higher power, higher speed welding, fluid flow is less turbulent, and such vortices are not formed. Corresponding experimental results show that porosity was absent in the melt runs made at higher power and higher welding speed. In contrast, large pores were present in melt runs made at lower power and lower welding speed. Based on the combination of experimental results and numerical predictions, it is proposed that porosity formation when keyhole laser welding may result from turbulent fluid flow behind the keyhole, with the larger the value of associated Reynolds number, the higher the possibility of porosity formation. For such fluid flow controlled porosities, measures to decrease Reynolds number of the fluid flow close to the keyhole could prove effective in reducing or avoiding porosity.

Multi-fluid renewable geo-energy systems and methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buscheck, Thomas A.

A geo-energy production method for extracting thermal energy from a reservoir formation. A production well extracts brine from the reservoir formation. A plurality of working fluid injection ("WFI") wells may be arranged proximate to the production well to at least partially circumscribe the production well. A plurality of brine production ("BP") wells may be arranged in a vicinity of the WFI wells to at least partially circumscribe the WFI wells. A working fluid is injected into the WFI wells to help drive a flow of the brine up through the production and BP wells, together with at least a portionmore » of the injected working fluid. Parasitic-load time-shifting and to storing of excess solar thermal energy may also be performed.« less

10+ years of ACORK: Continuous pore pressure record from the decollement zone at Nankai Trough off Muroto

NASA Astrophysics Data System (ADS)

Kinoshita, M.; Davis, E. E.; Becker, K.; Miyazaki, J.; Hulme, S.; Mendrum, R.; Toki, T.; Wheat, C. G.; Kasaya, T.

2012-12-01

Pore pressure and hydrological properties play key roles in governing coupling and slip behavior along the subducting plate interface. During the KR22-12 cruise, three dives were completed using ROV KAIKO onboard R/V KAIREI during Dec. 20-25, 2011, to retrieve pore pressure data and interstitial fluid samples from ACORKs at ODP Holes 808I and 1173B situated landward and seaward of the deformation front in the Nankai Trough off Cape Muroto. With 3-year-long and a 4-year-long new data records from Holes 808I and 1173B, respectively, we now have over 10-year-long continuous pressure records since June 2001 at both sites. Data from most monitoring depths show systematic variations in average pressure, and in formation pressure response to seafloor tidal loading. In 2005 and 2009, we observed significant decrease in the amplitudes of pressure response to semi-diurnal tidal loading at Hole 808I. Transient changes were observed at the time of several nearby earthquakes, including the 2011 Mar. 11 Tohoku earthquake, followed by long-lasting pressure changes in both holes starting on Mar. 23, 2011. Gas-tight fluid sampling operations were successfully carried out from the hydraulic port attached to the swellable packer inserted within the ACORK head at Hole 808I. The swellable packer was set in order to isolate the décollement zone that lies roughly 20 m below the bottom of casing at 922 m below the seafloor. We observed shimmering water venting through the port, and the flow rate was measured using a ball-type flowmeter. Fluid samples looked muddy, probably as a result of staining from the casing steel. We believe that the packer seal at the ACORK head is set properly, although the pore pressure at 922 m does not seem to have increased up to 2011. Still, the observed fluid seepage suggests a significant amount of fluid evacuated from the décollement zone since ACORK installation, which may have changed its hydrogeological condition.

Major element compositions of fluid inclusions from hydrothermal vein-type deposits record eroded sedimentary units in the Schwarzwald district, SW Germany

NASA Astrophysics Data System (ADS)

Walter, Benjamin F.; Burisch, Mathias; Marks, Michael A. W.; Markl, Gregor

2017-12-01

Mixing of sedimentary formation fluids with basement-derived brines is an important mechanism for the formation of hydrothermal veins. We focus on the sources of the sediment-derived fluid component in ore-forming processes and present a comprehensive fluid inclusion study on 84 Jurassic hydrothermal veins from the Schwarzwald mining district (SW Germany). Our data derive from about 2300 fluid inclusions and reveal differences in the average fluid composition between the northern, central, and southern Schwarzwald. Fluids from the northern and southern Schwarzwald are characterised by high salinities (18-26 wt% NaCl+CaCl2), low Ca/(Ca+Na) mole ratios (0.1-0.4), and variable Cl/Br mass ratios (30-1140). In contrast, fluids from the central Schwarzwald show even higher salinities (23-27 wt% NaCl+CaCl2), higher Ca/(Ca+Na) mole ratios (0.2-0.9), and less variable Cl/Br mass ratios (40-130). These fluid compositions correlate with the nature and thickness of the now eroded sedimentary cover rocks. Compared to the northern and the southern Schwarzwald, where halite precipitation occurred during the Middle Triassic, the sedimentary basin in the central Schwarzwald was relatively shallow at this time and no halite was precipitated. Accordingly, Cl/Br ratios of fluids from the central Schwarzwald provide no evidence for the reaction of a sedimentary brine with halite, whereas those from the northern and southern Schwarzwald do. Instead, elevated Ca/(Ca+Na), high SO4 contents, and relatively low Cl/Br imply the presence of a gypsum dissolution brine during vein formation in the central Schwarzwald which agrees with the reconstructed regional Triassic geology. Hence, the information archived in fluid inclusions from hydrothermal veins in the crystalline basement has the potential for reconstructing sedimentary rocks in the former overburden.

Bacterial communities associated with hydraulic fracturing fluids in thermogenic natural gas wells in North Central Texas, USA.

PubMed

Struchtemeyer, Christopher G; Elshahed, Mostafa S

2012-07-01

Hydraulic fracturing is used to increase the permeability of shale gas formations and involves pumping large volumes of fluids into these formations. A portion of the frac fluid remains in the formation after the fracturing process is complete, which could potentially contribute to deleterious microbially induced processes in natural gas wells. Here, we report on the geochemical and microbiological properties of frac and flowback waters from two newly drilled natural gas wells in the Barnett Shale in North Central Texas. Most probable number studies showed that biocide treatments did not kill all the bacteria in the fracturing fluids. Pyrosequencing-based 16S rRNA diversity analyses indicated that the microbial communities in the flowback waters were less diverse and completely distinct from the communities in frac waters. These differences in frac and flowback water communities appeared to reflect changes in the geochemistry of fracturing fluids that occurred during the frac process. The flowback communities also appeared well adapted to survive biocide treatments and the anoxic conditions and high temperatures encountered in the Barnett Shale. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Systems and methods for producing hydrocarbons from tar sands formations

DOEpatents

Li, Ruijian [Katy, TX; Karanikas, John Michael [Houston, TX

2009-07-21

A system for treating a tar sands formation is disclosed. A plurality of heaters are located in the formation. The heaters include at least partially horizontal heating sections at least partially in a hydrocarbon layer of the formation. The heating sections are at least partially arranged in a pattern in the hydrocarbon layer. The heaters are configured to provide heat to the hydrocarbon layer. The provided heat creates a plurality of drainage paths for mobilized fluids. At least two of the drainage paths converge. A production well is located to collect and produce mobilized fluids from at least one of the converged drainage paths in the hydrocarbon layer.

System and method for measuring permeability of materials

DOEpatents

Hallman, Jr., Russell Louis; Renner, Michael John

2013-07-09

Systems and methods are provided for measuring the permeance of a material. The permeability of the material may also be derived. Systems typically provide a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.

Material permeance measurement system and method

DOEpatents

Hallman, Jr., Russell Louis; Renner, Michael John [Oak Ridge, TN

2012-05-08

A system for measuring the permeance of a material. The permeability of the material may also be derived. The system provides a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.

Role of fluid in the mechanism of formation of volcaniclastic and coherent kimberlite facies: a diamond perspective

NASA Astrophysics Data System (ADS)

Fedortchouk, Yana; Chinn, Ingrid

2016-04-01

Dissolution features on diamonds recovered from kimberlites vary depending on the dissolution conditions and can be used as a reliable proxy for volatiles and their role in kimberlite emplacement. Volatiles determine the mechanism of magma emplacement; variation in volatile content and CO2/CO2+H2O ratio may affect the geology of kimberlite bodies and formation of coherent vs. volcaniclastic kimberlite facies. Here we examine the evolution of a kimberlite system during ascent using the resorption morphology of its diamond population. We use 655 macro-diamonds from a complex kimberlite pipe in the Orapa kimberlite field (Botswana) to examine the role of volatiles in the formation of the three facies comprising this pipe: two coherent kimberlite facies (CKA and CKB) and one massive volcaniclastic facies (MVK). The diamonds come from three drillholes through each of the studied kimberlite facies. Separate diamond samples derived from 2 - 13 m intervals were combined into 40 m depth intervals for statistical purposes. Four independent morphological methods allowed us to reliably discriminate products of resorption in kimberlite magma from resorption in the mantle, and use the former in our study. We found that the proportion of diamonds with kimberlitic resorption is the lowest in CKA - 22%, medium in MVK - 50%, and highest in CKB - 73%, and it increases with depth in each of the drillholes. Each kimberlite facies shows its own style of kimberlite-induced resorption on rounded tetrahexahedron (THH) diamonds: glossy surfaces in MVK, rough corroded surfaces in CKB, and combination of glossy surfaces with chains of circular pits in CKA, where these pits represent the initial stages of development of corrosive features observed on CKB diamonds. Based on the results of our previous experimental studies we propose that resorption of MVK diamonds is a product of interaction with COH fluid, resorption of CKB diamonds is a product of interaction with a volatile-undersaturated melt (possibly carbonatitic), and CKA diamonds show an overprint of melt-controlled resorption over a fluid-controlled resorption. We propose an early separation of the fluid phase during the ascent of this kimberlite magma, segregation of this fluid and rise towards the top of the magma column. Over-pressurisation caused by the expansion of this fluid worked as a driving force for the magma ascent acceleration. The magma column has separated into two parts: (1) the bubble-rich magma towards the top, explosive emplacement of which formed the MVK facies, followed by the "tailing" bubble-poor magma quietly arriving to form the CKA facies, and (2) magma that lost volatiles to the upwardly escaping bubbles, in which a slower ascent caused more intensive diamond resorption and delayed emplacement, forming the CKB facie. It is possible that formation, buoyancy, and growth of fluid bubbles controls the ascent of the kimberlite magma, where emplacement of bubble-rich magma forms volcaniclastic kimberlite facies, while fast rise of the bubbles through the magma column separates the fluid-rich phase that moves up preparing the conduit in the surrounding rocks and forms an explosive pipe at the surface, from a volatile-depleted magma, which slowly rises and fills the pipe with CK kimberlite facies.

Influenza A Virus Surveillance Based on Pre-Weaning Piglet Oral Fluid Samples.

PubMed

Panyasing, Y; Goodell, C; Kittawornrat, A; Wang, C; Levis, I; Desfresne, L; Rauh, R; Gauger, P C; Zhang, J; Lin, X; Azeem, S; Ghorbani-Nezami, S; Yoon, K-J; Zimmerman, J

2016-10-01

Influenza A virus (IAV) surveillance using pre-weaning oral fluid samples from litters of piglets was evaluated in four ˜12 500 sow and IAV-vaccinated, breeding herds. Oral fluid samples were collected from 600 litters and serum samples from their dams at weaning. Litter oral fluid samples were tested for IAV by virus isolation, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), RT-PCR subtyping and sequencing. Commercial nucleoprotein (NP) enzyme-linked immunosorbent assay (ELISA) kits and NP isotype-specific assays (IgM, IgA and IgG) were used to characterize NP antibody in litter oral fluid and sow serum. All litter oral fluid specimens (n = 600) were negative by virus isolation. Twenty-five oral fluid samples (25/600 = 4.2%) were qRT-PCR positive based on screening (Laboratory 1) and confirmatory testing (Laboratory 2). No hemagglutinin (HA) and neuraminidase (NA) gene sequences were obtained, but matrix (M) gene sequences were obtained for all qRT-PCR-positive samples submitted for sequencing (n = 18). Genetic analysis revealed that all M genes sequences were identical (GenBank accession no. KF487544) and belonged to the triple reassortant influenza A virus M gene (TRIG M) previously identified in swine. The proportion of IgM- and IgA-positive samples was significantly higher in sow serum and litter oral fluid samples, respectively (P < 0.01). Consistent with the extensive use of IAV vaccine, no difference was detected in the proportion of IgG- and blocking ELISA-positive sow serum and litter oral fluids. This study supported the use of oral fluid sampling as a means of conducting IAV surveillance in pig populations and demonstrated the inapparent circulation of IAV in piglets. Future work on IAV oral fluid diagnostics should focus on improved procedures for virus isolation, subtyping and sequencing of HA and NA genes. The role of antibody in IAV surveillance remains to be elucidated, but longitudinal assessment of specific antibody has the potential to provide information regarding patterns of infection, vaccination status and herd immunity. © 2014 Blackwell Verlag GmbH.

Investigating Created Properties of Nanoparticles Based Drilling Mud

NASA Astrophysics Data System (ADS)

Ghasemi, Nahid; Mirzaee, Mojtaba; Aghayari, Reza; Maddah, Heydar

2018-05-01

The success of drilling operations is heavily dependent on the drilling fluid. Drilling fluids cool down and lubricate the drill bit, remove cuttings, prevent formation damage, suspend cuttings and also cake off the permeable formation, thus retarding the passage of fluid into the formation. Typical micro or macro sized loss circulation materials (LCM) show limited success, especially in formations dominated by micropores, due to their relatively large sizes. Due to unique characteristics of nanoparticles such as their size and high surface area to volume ratio, they play an effective role in solving problems associated with the drilling fluid. In this study, we investigate the effect of adding Al2O3 and TiO2 nanoparticles into the drilling mud. Al2O3 and TiO2 nanoparticles were used in 20 and 60 nm of size and 0.05 wt% in concentration. Investigating the effects of temperature and pressure has shown that an increase in temperature can reduce the drilling mud rheological properties such as plastic viscosity, while an increase in pressure can enhance these properties. Also, the effects of pressure in high temperatures were less than those in low temperatures. Studying the effects of adding nanoparticles has shown that they can reduce the drilling mud rheological properties. Moreover, they can increase gel strength, reduce capillary suction time and decrease formation damage.

Pore Fluid Extraction by Reactive Solitary Waves in 3-D

NASA Astrophysics Data System (ADS)

Omlin, Samuel; Malvoisin, Benjamin; Podladchikov, Yury Y.

2017-09-01

In the lower crust, viscous compaction is known to produce solitary porosity and fluid pressure waves. Metamorphic (de)volatilization reactions can also induce porosity changes in response to the propagating fluid pressure anomalies. Here we present results from high-resolution simulations using Graphic Processing Unit parallel processing with a model that includes both viscous (de)compaction and reaction-induced porosity changes. Reactive porosity waves propagate in a manner similar to viscous porosity waves, but through a different mechanism involving fluid release and trap in the solid by reaction. These waves self-generate from red noise or an ellipsoidal porosity anomaly with the same characteristic size and abandon their source region to propagate at constant velocity. Two waves traveling at different velocities pass through each other in a soliton-like fashion. Reactive porosity waves thus provide an additional mechanism for fluid extraction at shallow depths with implications for ore formation, diagenesis, metamorphic veins formation, and fluid extraction from subduction zones.

Free Surface Flows and Extensional Rheology of Polymer Solutions

NASA Astrophysics Data System (ADS)

Dinic, Jelena; Jimenez, Leidy Nallely; Biagioli, Madeleine; Estrada, Alexandro; Sharma, Vivek

Free-surface flows - jetting, spraying, atomization during fuel injection, roller-coating, gravure printing, several microfluidic drop/particle formation techniques, and screen-printing - all involve the formation of axisymmetric fluid elements that spontaneously break into droplets by a surface-tension-driven instability. The growth of the capillary-driven instability and pinch-off dynamics are dictated by a complex interplay of inertial, viscous and capillary stresses for simple fluids. Additional contributions by elasticity, extensibility and extensional viscosity play a role for complex fluids. We show that visualization and analysis of capillary-driven thinning and pinch-off dynamics of the columnar neck in an asymmetric liquid bridge created by dripping-onto-substrate (DoS) can be used for characterizing the extensional rheology of complex fluids. Using a wide variety of complex fluids, we show the measurement of the extensional relaxation time, extensional viscosity, power-law index and shear viscosity. Lastly, we elucidate how polymer composition, flexibility, and molecular weight determine the thinning and pinch-off dynamics of polymeric complex fluids.

Behavior of fluids in a weightless environment

NASA Technical Reports Server (NTRS)

Fester, D. A.; Eberhardt, R. N.; Tegart, J. R.

1977-01-01

Fluid behavior in a low-g environment is controlled primarily by surface tension forces. Certain fluid and system characteristics determine the magnitude of these forces for both a free liquid surface and liquid in contact with a solid. These characteristics, including surface tension, wettability or contact angle, system geometry, and the relationships governing their interaction, are discussed. Various aspects of fluid behavior in a low-g environment are then presented. This includes the formation of static interface shapes, oscillation and rotation of drops, coalescence, the formation of foams, tendency for cavitation, and diffusion in liquids which were observed during the Skylab fluid mechanics science demonstrations. Liquid reorientation and capillary pumping to establish equilibrium configurations for various system geometries, observed during various free-fall (drop-tower) low-g tests, are also presented. Several passive low-g fluid storage and transfer systems are discussed. These systems use surface tension forces to control the liquid/vapor interface and provide gas-free liquid transfer and liquid-free vapor venting.

Analysis of cannabis in oral fluid specimens by GC-MS with automatic SPE.

PubMed

Choi, Hyeyoung; Baeck, Seungkyung; Kim, Eunmi; Lee, Sooyeun; Jang, Moonhee; Lee, Juseon; Choi, Hwakyung; Chung, Heesun

2009-12-01

Methamphetamine (MA) is the most commonly abused drug in Korea, followed by cannabis. Traditionally, MA analysis is carried out on both urine and hair samples and cannabis analysis in urine samples only. Despite the fact that oral fluid has become increasingly popular as an alternative specimen in the field of driving under the influence of drugs (DUID) and work place drug testing, its application has not been expanded to drug analysis in Korea. Oral fluid is easy to collect and handle and can provide an indication of recent drug abuse. In this study, we present an analytical method using GC-MS to determine tetrahydrocannabinol (THC) and its main metabolite 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in oral fluid. The validated method was applied to oral fluid samples collected from drug abuse suspects and the results were compared with those in urine. The stability of THC and THC-COOH in oral fluid stored in different containers was also investigated. Oral fluid specimens from 12 drug abuse suspects, submitted by the police, were collected by direct expectoration. The samples were screened with microplate ELISA. For confirmation they were extracted using automated SPE with mixed-mode cation exchange cartridge, derivatized and analyzed by GC-MS using selective ion monitoring (SIM). The concentrations ofTHC and THC-COOH in oral fluid showed a large variation and the results from oral fluid and urine samples from cannabis abusers did not show any correlation. Thus, detailed information about time interval between drug use and sample collection is needed to interpret the oral fluid results properly. In addition, further investigation about the detection time window ofTHC and THC-COOH in oral fluid is required to substitute oral fluid for urine in drug testing.

Containers and systems for the measurement of radioactive gases and related methods

DOEpatents

Mann, Nicholas R; Watrous, Matthew G; Oertel, Christopher P; McGrath, Christopher A

2017-06-20

Containers for a fluid sample containing a radionuclide for measurement of radiation from the radionuclide include an outer shell having one or more ports between an interior and an exterior of the outer shell, and an inner shell secured to the outer shell. The inner shell includes a detector receptacle sized for at least partial insertion into the outer shell. The inner shell and outer shell together at least partially define a fluid sample space. The outer shell and inner shell are configured for maintaining an operating pressure within the fluid sample space of at least about 1000 psi. Systems for measuring radioactivity in a fluid include such a container and a radiation detector received at least partially within the detector receptacle. Methods of measuring radioactivity in a fluid sample include maintaining a pressure of a fluid sample within a Marinelli-type container at least at about 1000 psi.

Optimization of Oxidation Temperature for Commercially Pure Titanium to Achieve Improved Corrosion Resistance

NASA Astrophysics Data System (ADS)

Bansal, Rajesh; Singh, J. K.; Singh, Vakil; Singh, D. D. N.; Das, Parimal

2017-03-01

Thermal oxidation of commercially pure titanium (cp-Ti) was carried out at different temperatures, ranging from 200 to 900 °C to achieve optimum corrosion resistance of the thermally treated surface in simulated body fluid. Scanning electron microscopy, x-ray diffraction, Raman spectroscopy and electrochemical impedance spectroscopy techniques were used to characterize the oxides and assess their protective properties exposed in the test electrolyte. Maximum resistance toward corrosion was observed for samples oxidized at 500 °C. This was attributed to the formation of a composite layer of oxides at this temperature comprising Ti2O3 (titanium sesquioxide), anatase and rutile phases of TiO2 on the surface of cp-Ti. Formation of an intact and pore-free oxide-substrate interface also improved its corrosion resistance.

Fluid displacement during droplet formation at microfluidic flow-focusing junctions.

PubMed

Huang, Haishui; He, Xiaoming

2015-11-07

Microdroplets and microcapsules have been widely produced using microfluidic flow-focusing junctions for biomedical and chemical applications. However, the multiphase microfluidic flow at the flow-focusing junction has not been well investigated. In this study, the displacement of two (core and shell) aqueous fluids that disperse into droplets altogether in a carrier oil emulsion was investigated both numerically and experimentally. It was found that extensive displacement of the two aqueous fluids within the droplet during its formation could occur as a result of the shear effect of the carrier fluid and the capillary effect of interfacial tension. We further identified that the two mechanisms of fluid displacement can be evaluated by two dimensionless parameters. The quantitative relationship between the degree of fluid displacement and these two dimensionless parameters was determined experimentally. Finally, we demonstrated that the degree of fluid displacement could be controlled to generate hydrogel microparticles of different morphologies using planar or nonplanar flow-focusing junctions. These findings should provide useful guidance to the microfluidic production of microscale droplets or capsules for various biomedical and chemical applications.

Effects of surface properties on droplet formation inside a microfluidic device

NASA Astrophysics Data System (ADS)

Steinhaus, Ben; Shen, Amy

2004-11-01

Micro-fluidic devices offer a unique method of creating and controlling droplets on small length scales. A microfluidic device is used to study the effects of surface properties on droplet formation of a 2-phase flow system. Four phase diagrams are generated to compare the dynamics of the 2 immiscible fluid system (silicone oil and water) inside microchannels with different surface properties. Results show that the channel surface plays an important role in determining the flow patterns and the droplet formation of the 2-phase fluid system.

Microfluidic Biochip Design

NASA Technical Reports Server (NTRS)

Panzarella, Charles

2004-01-01

As humans prepare for the exploration of our solar system, there is a growing need for miniaturized medical and environmental diagnostic devices for use on spacecrafts, especially during long-duration space missions where size and power requirements are critical. In recent years, the biochip (or Lab-on-a- Chip) has emerged as a technology that might be able to satisfy this need. In generic terms, a biochip is a miniaturized microfluidic device analogous to the electronic microchip that ushered in the digital age. It consists of tiny microfluidic channels, pumps and valves that transport small amounts of sample fluids to biosensors that can perform a variety of tests on those fluids in near real time. It has the obvious advantages of being small, lightweight, requiring less sample fluids and reagents and being more sensitive and efficient than larger devices currently in use. Some of the desired space-based applications would be to provide smaller, more robust devices for analyzing blood, saliva and urine and for testing water and food supplies for the presence of harmful contaminants and microorganisms. Our group has undertaken the goal of adapting as well as improving upon current biochip technology for use in long-duration microgravity environments. In addition to developing computational models of the microfluidic channels, valves and pumps that form the basis of every biochip, we are also trying to identify potential problems that could arise in reduced gravity and develop solutions to these problems. One such problem is due to the prevalence of bubbly sample fluids in microgravity. A bubble trapped in a microfluidic channel could be detrimental to the operation of a biochip. Therefore, the process of bubble formation in microgravity needs to be studied, and a model of this process has been developed and used to understand how bubbles develop and move through biochip components. It is clear that some type of bubble filter would be necessary in Space, and several bubble filter designs are being evaluated.

Cold-seep-driven carbonate deposits at the Central American forearc: contrasting evolution and timing in escarpment and mound settings

NASA Astrophysics Data System (ADS)

Liebetrau, V.; Augustin, N.; Kutterolf, S.; Schmidt, M.; Eisenhauer, A.; Garbe-Schönberg, D.; Weinrebe, W.

2014-10-01

Continuous surface cores of cold-seep carbonates were recovered offshore Pacific Nicaragua and Costa Rica from 800 to 1,500-m water depths (Meteor 66/3) in order to decipher their evolution and methane enriched fluid emanation in contrasting geological settings. Cores from the mounds Iguana, Perezoso, Baula V and from the Jaco Scarp escarpment were used for a multi-method approach. For both settings aragonite was revealed as dominant authigenic carbonate phase in vein fillings and matrix cementation, followed by Mg-calcite as second most abundant. This common precipitation process of CaCO3 polymorphs could be ascribed as indirectly driven by chemical changes of the advecting pore water due to anaerobic oxidation of methane. A more direct influence of seep-related microbial activity on the authigenic mineral assemblage in both settings is probably reflected by the observed minor amounts of dolomite and a dolomite-like CaMg carbonate (MgCO3 ~ 42 %). δ13C data of Jaco Scarp samples are significantly lower (-43 to -56 ‰ PDB) than for mound samples (-22 to -36 ‰ PDB), indicating differences in fluid composition and origin. Noteworthy, δ18O values of Scarp samples correlate most closely with the ocean signature at their time of formation. Documenting the archive potential, a high resolution case study of a mound core implies at least 40 changes in fluid supply within a time interval of approximately 14 ky. As most striking difference, the age data indicate a late-stage downward-progressing cementation front for all three mound cap structures (approx. 2-5 cm/ky), but a significantly faster upward carbonate buildup in the bulging sediments on top of the scarp environment (approx. 120 cm/ky). The latter data set leads to the hypothesis of chemoherm carbonate emplacement in accord with reported sedimentation rates until decompression of the advective fluid system, probably caused by the Jaco Scarp landslide and dating this to approximately 13,000 years ago.

Surface sampling concentration and reaction probe with controller to adjust sampling position

DOEpatents

Van Berkel, Gary J.; ElNaggar, Mariam S.

2016-07-19

A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

Stable isotopic evidence for fluid flow and fluid/rock interaction during thrust faulting in Pumpkin Valley shale and Rome Formation, east Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, B.K.; Haase, C.S.

1989-08-01

The Pumpkin Valley Shale and the underlying Rome Formation form the lower portions of the Copper Creek and White Oak Mountain thrust sheets in east Tennessee. The Pumpkin Valley Shale consists of shale and mudstone with subordinate amounts of interbedded siltstone. The Rome Formation is composed predominantly of sandstone with interbedded shale and siltstone toward the base of the formation. The percentage of illite increases from 20% to over 80% of the bulk clay mineralogy toward the base of the section. Porosity is occluded by quartz, phyllosilicate, and calcite cements. Both formations contain calcite-filled and, less commonly, quartz-filled Alleghenian fracturesmore » and joints.« less

Gut inflammation and expression of ICC in a fetal lamb model of fetoscopic intervention for gastroschisis.

PubMed

Krebs, Thomas; Boettcher, Michael; Schäfer, Hansjörg; Eschenburg, Georg; Wenke, Katharina; Appl, Birgit; Roth, Beate; Andreas, Thomas; Schmitz, Carla; Fahje, Rebecca; Jacobsen, Birthe; Tiemann, Bastian; Reinshagen, Konrad; Hecher, Kurt; Bergholz, Robert

2014-08-01

The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model. Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used. In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls. Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation.

The Role of Electrical Anisotropy in Modeling and Interpreting Controlled-Source Electromagnetic Responses for Hydraulic Fracture Monitoring

NASA Astrophysics Data System (ADS)

Trevino, S., III; Hickey, M. S.; Everett, M. E.

2017-12-01

Controlled-Source Electromagnetics (CSEM) can be used to monitor the movement and extent of injection fluid during a hydraulic fracture. The response of the fluid to energization by a CSEM source is dependent upon the electrical conductivity difference between the fluid and background geological formation. An important property that must be taken into account when modeling and interpreting CSEM responses is that electrical conductivity may be anisotropic. We study the effect of electrical anisotropy in both the background formation and the fluid-injection zone. First, various properties of the background formation can affect anisotropy including variations in grain size, composition and bedding-plane orientation. In certain formations, such as shale, the horizontal component of the conductivity can be more than an order of magnitude larger than the vertical component. We study this effect by computing differences in surface CSEM responses using the analytic 1-D anisotropic primary solution of a horizontal electric dipole positioned at the surface. Second, during hydraulic fracturing, the injected fluid can create new fractures and infill existing natural fractures. To include the explicit fracture geometry in modeling, a large increase in the number of nodes and computational time is required which may not be feasible. An alternative is to instead model the large-scale fracture geometry as a uniform slab with an appropriate bulk conductivity. Micro-scale fracture geometry may cause preferential fluid propagation in a single direction or plane which can be represented by electrical anisotropy of the slab. To study such effects of bulk anisotropy on CSEM responses we present results from multiple scenarios of surface to surface hydraulic fracture monitoring using 3-D finite element modeling. The model uses Coulomb-gauged potentials to solve Maxwell's equations in the frequency domain and we have updated the code to allow a triaxial electrical conductivity tensor to be specified. By allowing for formation and target electrical anisotropy these modeling results contribute to a better understanding and faster interpretation of field data.

Experimental study of carbonate formation in oceanic peridotite

NASA Astrophysics Data System (ADS)

Grozeva, Niya G.; Klein, Frieder; Seewald, Jeffrey S.; Sylva, Sean P.

2017-02-01

Interactions of CO2-rich aqueous fluids with mantle peridotite have major implications for geochemical budgets and microbial life in the shallow oceanic lithosphere through the formation of carbonate minerals and reduced carbon species. However, the underlying mechanisms controlling the transformation of CO2 to carbonates in ultramafic-hosted hydrothermal systems remain incompletely understood. A long-term laboratory experiment was conducted at 300 °C and 35 MPa to investigate serpentinization and carbonate formation pathways during hydrothermal alteration of peridotite. Powdered harzburgite was initially reacted with a Ca-rich aqueous fluid for 14,592 h (608 days) and changes in fluid composition were monitored with time. Once the system reached a steady state, a CO2(aq)-rich fluid was injected and allowed to react with the system for 5907 h (246 days). Fluid speciation and mineral analyses suggest that serpentinization of harzburgite in the CO2-poor system led to the precipitation of serpentine, brucite, magnetite, and minor calcite, in addition to other minor phases including chlorite and sulfur-poor Ni sulfides. The addition of the CO2(aq)-rich fluid caused dolomite, Ca-rich dolomite, and high-Mg calcite to form at the expense of olivine, calcite, and brucite, while serpentine remained unreactive. Replacement textures and mineral assemblages mimic those documented in carbonate-altered seafloor serpentinites, particularly those from the Mid-Atlantic Ridge and the Iberia Margin. In contrast to thermodynamic predictions, magnesite did not form in the experiment because the dissolution of clinopyroxene, in combination with the lack of serpentine reactivity, maintained low Mg/Ca ratios in solution. Clinopyroxene dissolution and unreactive serpentine may similarly maintain low Mg/Ca ratios in submarine serpentinization systems and limit magnesite formation in subseafloor environments. Results of this study suggest that the formation of Ca-Mg carbonates by mineral carbonation is favorable in subseafloor serpentinization systems and likely represents a significant, but poorly quantified, carbon sink in hydrothermally altered oceanic lithosphere at slow-spreading mid-ocean ridges.

Fluid driven fracture mechanics in highly anisotropic shale: a laboratory study with application to hydraulic fracturing

NASA Astrophysics Data System (ADS)

Gehne, Stephan; Benson, Philip; Koor, Nick; Enfield, Mark

2017-04-01

The finding of considerable volumes of hydrocarbon resources within tight sedimentary rock formations in the UK led to focused attention on the fundamental fracture properties of low permeability rock types and hydraulic fracturing. Despite much research in these fields, there remains a scarcity of available experimental data concerning the fracture mechanics of fluid driven fracturing and the fracture properties of anisotropic, low permeability rock types. In this study, hydraulic fracturing is simulated in a controlled laboratory environment to track fracture nucleation (location) and propagation (velocity) in space and time and assess how environmental factors and rock properties influence the fracture process and the developing fracture network. Here we report data on employing fluid overpressure to generate a permeable network of micro tensile fractures in a highly anisotropic shale ( 50% P-wave velocity anisotropy). Experiments are carried out in a triaxial deformation apparatus using cylindrical samples. The bedding planes are orientated either parallel or normal to the major principal stress direction (σ1). A newly developed technique, using a steel guide arrangement to direct pressurised fluid into a sealed section of an axially drilled conduit, allows the pore fluid to contact the rock directly and to initiate tensile fractures from the pre-defined zone inside the sample. Acoustic Emission location is used to record and map the nucleation and development of the micro-fracture network. Indirect tensile strength measurements at atmospheric pressure show a high tensile strength anisotropy ( 60%) of the shale. Depending on the relative bedding orientation within the stress field, we find that fluid induced fractures in the sample propagate in two of the three principal fracture orientations: Divider and Short-Transverse. The fracture progresses parallel to the bedding plane (Short-Transverse orientation) if the bedding plane is aligned (parallel) with the direction of σ1. Conversely, the crack plane develops perpendicular to the bedding plane, if the bedding plane is orientated normal to σ1. Fracture initiation pressures are higher in the Divider orientation ( 24MPa) than in the Short-Transverse orientation ( 14MPa) showing a tensile strength anisotropy ( 42%) comparable to ambient tensile strength results. We then use X-Ray Computed Tomography (CT) 3D-images to evaluate the evolved fracture network in terms of fracture pattern, aperture and post-test water permeability. For both fracture orientations, very fine, axial fractures evolve over the entire length of the sample. For the fracturing in the Divider orientation, it has been observed, that in some cases, secondary fractures are branching of the main fracture. Test data from fluid driven fracturing experiments suggest that fracture pattern, fracture propagation trajectories and fracturing fluid pressure (initiation and propagation pressure) are predominantly controlled by the interaction between the anisotropic mechanical properties of the shale and the anisotropic stress environment. The orientation of inherent rock anisotropy relative to the principal stress directions seems to be the main control on fracture orientation and required fracturing pressure.

Investigation of Controlling Factors Impacting Water Quality in Shale Gas Produced Brine

NASA Astrophysics Data System (ADS)

Fan, W.; Hayes, K. F.; Ellis, B. R.

2014-12-01

The recent boom in production of natural gas from unconventional reservoirs has generated a substantial increase in the volume of produced brine that must be properly managed to prevent contamination of fresh water resources. Produced brine, which includes both flowback and formation water, is often highly saline and may contain elevated concentrations of naturally occurring radioactive material and other toxic elements. These characteristics present many challenges with regard to designing effective treatment and disposal strategies for shale gas produced brine. We will present results from a series of batch experiments where crushed samples from two shale formations in the Michigan Basin, the Antrim and Utica-Collingwood shales, were brought into contact with synthetic hydraulic fracturing fluids under in situ temperature and pressure conditions. The Antrim has been an active shale gas play for over three decades, while the Utica-Collingwood formation (a grouped reservoir consisting of the Utica shale and Collingwood limestone) is an emerging shale gas play. The goal of this study is to investigate the influence of water-rock interactions in controlling produced water quality. We evaluate toxic element leaching from shale samples in contact with model hydraulic fracturing fluids under system conditions corresponding to reservoir depths up to 1.5 km. Experimental results have begun to elucidate the relative importance of shale mineralogy, system conditions, and chemical additives in driving changes in produced water quality. Initial results indicate that hydraulic fracturing chemical additives have a strong influence on the extent of leaching of toxic elements from the shale. In particular, pH was a key factor in the release of uranium (U) and divalent metals, highlighting the importance of the mineral buffering capacity of the shale. Low pH values persisted in the Antrim and Utica shale experiments and resulted in higher U extraction efficiencies than that observed in the presence of the carbonate-rich Collingwood limestone. In addition to assessing U leaching, we also measured the activity of 226Ra and 228Ra via high-resolution gamma ray spectroscopy. Laboratory results will be compared to observations from a complimentary field sampling campaign of Antrim produced brine.

18 CFR 806.22 - Standards for consumptive uses of water.

Code of Federal Regulations, 2012 CFR

2012-04-01

... shall apply to all water, including stimulation additives, flowback, drilling fluids, formation fluids... with the mitigation requirements set forth in § 806.22(b). (6) Any flowback or production fluids... such approvals. (8) The project sponsor shall certify to the Commission that all flowback and...

18 CFR 806.22 - Standards for consumptive uses of water.

Code of Federal Regulations, 2014 CFR

2014-04-01

... shall apply to all water, including stimulation additives, flowback, drilling fluids, formation fluids... with the mitigation requirements set forth in § 806.22(b). (6) Any flowback or production fluids... such approvals. (8) The project sponsor shall certify to the Commission that all flowback and...

Characterizing the variability in chemical composition of flowback and produced waters - results from lab and field studies

NASA Astrophysics Data System (ADS)

Vieth-Hillebrand, Andrea; Wilke, Franziska D. H.; Schmid, Franziska E.; Zhu, Yaling; Lipińska, Olga; Konieczyńska, Monika

2017-04-01

The huge volumes and unknown composition of flowback and produced waters cause major public concerns about the environmental and social compatibility of hydraulic fracturing and the exploitation of gas from unconventional reservoirs. Flowback and produced waters contain not only residues of fracking additives but also chemical species that are dissolved from the target shales themselves. Shales are a heterogeneous mixture of minerals, organic matter, and formation water and little is actually understood about the fluid-rock interactions occurring during hydraulic fracturing of the shales and their effects on the chemical composition of flowback and produced water. To overcome this knowledge gap, interactions of different shales with different artificial stimulation fluids were studied in lab experiments under ambient and elevated temperature and pressure conditions. These lab experiments showed clearly that fluid-rock interactions change the chemical composition of the initial stimulation fluid and that geochemistry of the fractured shale is relevant for understanding flowback water composition. In addition, flowback water samples were taken after hydraulic fracturing of one horizontal well in Pomeranian region, Poland and investigated for their chemical composition. With this presentation, results from lab and field studies will be presented and compared to decipher possible controls on chemical compositions of flowback and produced water.

Cloud fluid models of gas dynamics and star formation in galaxies

NASA Technical Reports Server (NTRS)

Struck-Marcell, Curtis; Scalo, John M.; Appleton, P. N.

1987-01-01

The large dynamic range of star formation in galaxies, and the apparently complex environmental influences involved in triggering or suppressing star formation, challenges the understanding. The key to this understanding may be the detailed study of simple physical models for the dominant nonlinear interactions in interstellar cloud systems. One such model is described, a generalized Oort model cloud fluid, and two simple applications of it are explored. The first of these is the relaxation of an isolated volume of cloud fluid following a disturbance. Though very idealized, this closed box study suggests a physical mechanism for starbursts, which is based on the approximate commensurability of massive cloud lifetimes and cloud collisional growth times. The second application is to the modeling of colliding ring galaxies. In this case, the driving processes operating on a dynamical timescale interact with the local cloud processes operating on the above timescale. The results is a variety of interesting nonequilibrium behaviors, including spatial variations of star formation that do not depend monotonically on gas density.

Microchannel gel electrophoretic separation systems and methods for preparing and using

DOEpatents

Herr, Amy E; Singh, Anup K; Throckmorton, Daniel J

2015-02-24

A micro-analytical platform for performing electrophoresis-based immunoassays was developed by integrating photopolymerized cross-linked polyacrylamide gels within a microfluidic device. The microfluidic immunoassays are performed by gel electrophoretic separation and quantifying analyte concentration based upon conventional polyacrylamide gel electrophoresis (PAGE). To retain biological activity of proteins and maintain intact immune complexes, native PAGE conditions were employed. Both direct (non-competitive) and competitive immunoassay formats are demonstrated in microchips for detecting toxins and biomarkers (cytokines, c-reactive protein) in bodily fluids (serum, saliva, oral fluids). Further, a description of gradient gels fabrication is included, in an effort to describe methods we have developed for further optimization of on-chip PAGE immunoassays. The described chip-based PAGE immunoassay method enables immunoassays that are fast (minutes) and require very small amounts of sample (less than a few microliters). Use of microfabricated chips as a platform enables integration, parallel assays, automation and development of portable devices.

Fluid flow through the larynx channel

NASA Astrophysics Data System (ADS)

Miller, J. A.; Pereira, J. C.; Thomas, D. W.

1988-03-01

The classic two-mass model of the larynx channel is extended by including the false vocal folds and the laryngeal ventricle. Several glottis profiles are postulated to exist which are the result of the forces applied to the mucus membrane due to intraglottal pressure variation. These profiles constrain the air flow which allows the formation of one or two "venae contractae". The location of these influences the pressure in the glottis and layrngeal ventricle and also gives rise to additional viscous losses as well as losses due to flow enlargement. Sampled waveforms are calculated from the model for volume velocity, glottal area, Reynolds number and fluid forces over the vocal folds for various profiles. Results show that the computed waveforms agree with physiological data [1,2] and that it is not necessary to use any empirical constants to match the simulation results. Also, the onset of phonation is shown to be possible either with abduction or adduction of the vocal folds.

Microfluidic manipulation of magnetic flux domains in type-I superconductors: droplet formation, fusion and fission.

PubMed

Berdiyorov, G R; Milošević, M V; Hernández-Nieves, A D; Peeters, F M; Domínguez, D

2017-09-21

The magnetic flux domains in the intermediate state of type-I superconductors are known to resemble fluid droplets, and their dynamics in applied electric current is often cartooned as a "dripping faucet". Here we show, using the time-depended Ginzburg-Landau simulations, that microfluidic principles hold also for the determination of the size of the magnetic flux-droplet as a function of the applied current, as well as for the merger or splitting of those droplets in the presence of the nanoengineered obstacles for droplet motion. Differently from fluids, the flux-droplets in superconductors are quantized and dissipative objects, and their pinning/depinning, nucleation, and splitting occur in a discretized form, all traceable in the voltage measured across the sample. At larger applied currents, we demonstrate how obstacles can cause branching of laminar flux streams or their transformation into mobile droplets, as readily observed in experiments.

Microchannel gel electrophoretic separation systems and methods for preparing and using

DOEpatents

Herr, Amy; Singh, Anup K; Throckmorton, Daniel J

2013-09-03

A micro-analytical platform for performing electrophoresis-based immunoassays was developed by integrating photopolymerized cross-linked polyacrylamide gels within a microfluidic device. The microfluidic immunoassays are performed by gel electrophoretic separation and quantifying analyte concentration based upon conventional polyacrylamide gel electrophoresis (PAGE). To retain biological activity of proteins and maintain intact immune complexes, native PAGE conditions were employed. Both direct (non-competitive) and competitive immunoassay formats are demonstrated in microchips for detecting toxins and biomarkers (cytokines, c-reactive protein) in bodily fluids (serum, saliva, oral fluids). Further, a description of gradient gels fabrication is included, in an effort to describe methods we have developed for further optimization of on-chip PAGE immunoassays. The described chip-based PAGE immunoassay method enables immunoassays that are fast (minutes) and require very small amounts of sample (less than a few microliters). Use of microfabricated chips as a platform enables integration, parallel assays, automation and development of portable devices.

Geologic and hydraulic characteristics of selected shaly geologic units in Oklahoma

USGS Publications Warehouse

Becker, C.J.; Overton, M.D.; Johnson, K.S.; Luza, K.V.

1997-01-01

Information was collected on the geologic and hydraulic characteristics of three shale-dominated units in Oklahoma-the Dog Creek Shale and Chickasha Formation in Canadian County, Hennessey Group in Oklahoma County, and the Boggy Formation in Pittsburg County. The purpose of this project was to gain insight into the characteristics controlling fluid flow in shaly units that could be targeted for confinement of hazardous waste in the State and to evaluate methods of measuring hydraulic characteristics of shales. Permeameter results may not indicate in-place small-scale hydraulic characteristics, due to pretest disturbance and deterioration of core samples. The Dog Creek Shale and Chickasha Formation hydraulic conductivities measured by permeameter methods ranged from 2.8 times 10 to the negative 11 to 3.0 times 10 to the negative 7 meter per second in nine samples and specific storage from 3.3 times 10 to the negative 4 to 1.6 times 10 to the negative 3 per meter in four samples. Hennessey Group hydraulic conductivities ranged from 4.0 times 10 to the negative 12 to 4.0 times 10 to the negative 10 meter per second in eight samples. Hydraulic conductivity in the Boggy Formation ranged from 1.7 times 10 to the negative 12 to 1.0 times 10 to the negative 8 meter per second in 17 samples. The hydraulic properties of isolated borehole intervals of average length of 4.5 meters in the Hennessey Group and the Boggy Formation were evaluated by a pressurized slug-test method. Hydraulic conductivities obtained with this method tend to be low because intervals with features that transmitted large volumes of water were not tested. Hennessey Group hydraulic conductivities measured by this method ranged from 3.0 times 10 to the negative 13 to 1.1 times 10 to the negative 9 meter per second; the specific storage values are small and may be unreliable. Boggy Formation hydraulic conductivities ranged from 2.0 times 10 to the negative 13 to 2.7 times 10 to the negative 10 meter per second and specific storage values in these tests also are small and may be unreliable. A substantially higher hydraulic conductivity of 3.0 times 10 to the negative 8 meter per second was measured in one borehole 30 meters deep in the Boggy Formation using an open hole slug-test method.

Extant or Absent: Formation Water in New York State Drinking Water Wells

NASA Astrophysics Data System (ADS)

Christian, K.; Lautz, L. K.

2013-12-01

The current moratorium on hydraulic fracturing in New York State (NYS) provides an opportunity to collect baseline shallow groundwater quality data pre-hydraulic fracturing, which is essential for determining the natural variability of groundwater chemistry and to evaluate future claims of impaired groundwater quality if hydraulic fracturing occurs in the State. Concerns regarding the future environmental impact of shale gas extraction in NYS include potential shallow groundwater contamination due to migration of methane or formation water from shale gas extraction sites. Treatment, storage and disposal of saline flowback fluids after gas extraction could also be a source of water contamination. In this study, we combine southern NYS shallow groundwater chemistry data from Project Shale-Water Interaction Forensic Tools (SWIFT, n=60), the National Uranium Resource Evaluation program (NURE, n=684), and the USGS 305(b) Ambient Groundwater Quality Monitoring program (USGS, n=89) to examine evidence of formation water mixing with groundwater using the methodology of Warner et al. (2012). Groundwater characterized as low salinity (<20 mg/L Cl-) accounted for 72% of samples and 28% of samples had high salinity (>20 mg/L Cl-). A plot of bromide versus chloride shows high salinity groundwater samples with Br/Cl ratios >0.0001 fall on the mixing line between low salinity groundwater and Appalachian Basin formation water. Based on the observed linear relationship between bromide and chloride, it appears there is up to 1% formation water mixing with shallow groundwater in the region. The presence of formation water in shallow groundwater would indicate the existence of natural migratory pathways between deep formation wells and shallow groundwater aquifers. A plot of sodium versus chloride also illustrates a linear trend for Type D waters (R^2= 0.776), but the relationship is weaker than that for bromide versus chloride (R^2= 0.924). Similar linear relationships are not observed between other ions and chloride, including Mg, Ca, and Sr. If high salinity groundwater samples from NYS contain small percentages of formation water, we expect linear relationships between chloride and these other, generally conservative ions. The absence of these linear relationships suggests high salinity could be associated with contamination by landfill leachate, septic effluent, road salt, or other potential sources of elevated salt. Future work needs to determine if mixing of shallow groundwater with other potential sources of salinity, such as road deicers, can explain the observed linear relationships. Strontium isotopes from shallow groundwater samples will also be compared to those for NY formation water.

In-situ Mechanical Manipulation of Wellbore Cements as a Solution to Leaky Wells

NASA Astrophysics Data System (ADS)

Kupresan, D.; Radonjic, M.; Heathman, J.

2013-12-01

Wellbore cement provides casing support, zonal isolation, and casing protection from corrosive fluids, which are essential for wellbore integrity. Cements can undergo one or more forms of failure such as debonding at cement/formation and cement/casing interface, fracturing and defects within cement matrix. Failures and defects within cement will ultimately lead to fluids migration, resulting in inter-zonal fluid migration and premature well abandonment. There are over 27,000 abandoned oil and gas wells only in The Gulf of Mexico (some of them dating from the late 1940s) with no gas leakage monitoring. Cement degradation linked with carbon sequestration can potentially lead to contamination of fresh water aquifers with CO2. Gas leaks can particularly be observed in deviated wells used for hydraulic fracking (60% leakage rate as they age) as high pressure fracturing increases the potential for migration pathways. Experimental method utilized in this study enables formation of impermeable seals at interfaces present in a wellbore by mechanically manipulating wellbore cement. Preliminary measurements obtained in bench scale experiments demonstrate that an impermeable cement/formation and cement/casing interface can be obtained. In post-modified cement, nitrogen gas flow-through experiments showed complete zonal isolation and no permeability in samples with pre-engineered microannulus. Material characterization experiments of modified cement revealed altered microstructural properties of cement as well as changes in mineralogical composition. Calcium-silicate-hydrate (CSH), the dominant mineral in hydrated cement which provides low permeability of cement, was modified as a result of cement pore water displacement, resulting in more dense structures. Calcium hydroxide (CH), which is associated with low resistance of cement to acidic fluids and therefore detrimental in most wellbore cements, was almost completely displaced and/or integrated in CSH as a result of mechanical manipulation (shear stress). The main advantage of this methodology is that mechanical manipulation of cement can induce healing of existing fractures, channels and microannulus seal in a wellbore without introducing new materials (e.g. cement squeeze jobs). Furthermore, this methodology is less sensitive to the influence of downhole conditions such as pressure, temperature and formation fluids, since it uses cement pore water as a medium to alter cement sheath. Based on lab experiments observation, it is possible to perceive that once tested at the industrial scale and if successful, the implementation of this method in the field can potentially mitigate leaky wells in CO2 sequestration projects, wellbores completed for hydraulic-fracturing and other conventional oil and gas producing wells. Key words: Wellbore cement integrity; Leaky wells; Cement microstructures; Casing expansion effect on cement mineralogy alterations.

Preferences for oral fluid rapid HIV self-testing among social media-using young black, Hispanic, and white men-who-have-sex-with-men (YMSM): implications for future interventions

PubMed Central

Merchant, R.C.; Clark, M.A.; Liu, T.; Rosenberger, J.G.; Romanoff, J.; Bauermeister, J.; Mayer, K.H.

2016-01-01

Objectives We assessed preferences of social media-using young black, Hispanic and white men-who-have-sex-with-men (YMSM) for oral fluid rapid HIV self-testing, as compared with other currently available HIV testing options. We also identified aspects of the oral fluid rapid HIV self-test that might influence preferences for using this test instead of other HIV testing options and determined if consideration of HIV testing costs and the potential future availability of fingerstick rapid HIV self-testing change HIV testing preferences. Study design Anonymous online survey. Methods HIV-uninfected YMSM across the United States recruited from multiple social media platforms completed an online survey about willingness to use, opinions about and their preferences for using oral fluid rapid HIV self-testing and five other currently available HIV testing options. In a pre/post questionnaire format design, participants first indicated their preferences for using the six HIV testing options (pre) before answering questions that asked their experience with and opinions about HIV testing. Although not revealed to participants and not apparent in the phrasing of the questions or responses, the opinion questions concerned aspects of oral fluid rapid HIV self-testing (e.g. its possible advantages/disadvantages, merits/demerits, and barriers/facilitators). Afterward, participants were queried again about their HIV testing preferences (post). After completing these questions, participants were asked to re-indicate their HIV testing preferences when considering they had to pay for HIV testing and if fingerstick blood sample rapid HIV self-testing were an additional testing option. Aspects about the oral fluid rapid HIV self-test associated with influencing increased the preference for using the test (post assessment vs pre-assessment of opinion topics) were identified through multivariable regression models that adjusted for participant characteristics. Results Of the 1975 YMSM participants, the median age was 22 years (IQR 20–23); 19% were black, 36% Hispanic, and 45% white; and 18% previously used an oral fluid rapid HIV self-test. Although views about oral fluid rapid HIV self-testing test were favorable, few intended to use the test. Aspects about the oral fluid rapid HIV self-test associated with an increased preference for using the test were its privacy features, that it motivated getting tested more often or as soon as possible, and that it conferred feelings of more control over one’s sexual health. Preferences for the oral fluid rapid HIV self-test were lower when costs were considered, yet these YMSM were much more interested in fingerstick blood sampling than oral fluid sampling rapid HIV self-testing. Conclusions Despite the perceived advantages of the oral fluid rapid HIV self-test and favorable views about it by this population, prior use as well as future intention in using the test were low. Aspects about oral fluid rapid HIV self-testing identified as influential in this study might assist in interventions aimed to increase its use among this high HIV risk population as a means of encouraging regular HIV testing, identifying HIV-infected persons, and linking them to care. Although not yet commercially available in the United States, fingerstick rapid HIV self-testing might help motivate YMSM to be tested more than oral fluid rapid HIV self-testing. PMID:28359394

Preferences for oral fluid rapid HIV self-testing among social media-using young black, Hispanic, and white men-who-have-sex-with-men (YMSM): implications for future interventions.

PubMed

Merchant, R C; Clark, M A; Liu, T; Rosenberger, J G; Romanoff, J; Bauermeister, J; Mayer, K H

2017-04-01

We assessed preferences of social media-using young black, Hispanic and white men-who-have-sex-with-men (YMSM) for oral fluid rapid HIV self-testing, as compared to other currently available HIV testing options. We also identified aspects of the oral fluid rapid HIV self-test that might influence preferences for using this test instead of other HIV testing options and determined if consideration of HIV testing costs and the potential future availability of fingerstick rapid HIV self-testing change HIV testing preferences. Anonymous online survey. HIV-uninfected YMSM across the United States recruited from multiple social media platforms completed an online survey about willingness to use, opinions about and their preferences for using oral fluid rapid HIV self-testing and five other currently available HIV testing options. In a pre/post questionnaire format design, participants first indicated their preferences for using the six HIV testing options (pre) before answering questions that asked their experience with and opinions about HIV testing. Although not revealed to participants and not apparent in the phrasing of the questions or responses, the opinion questions concerned aspects of oral fluid rapid HIV self-testing (e.g. its possible advantages/disadvantages, merits/demerits, and barriers/facilitators). Afterward, participants were queried again about their HIV testing preferences (post). After completing these questions, participants were asked to re-indicate their HIV testing preferences when considering they had to pay for HIV testing and if fingerstick blood sample rapid HIV self-testing were an additional testing option. Aspects about the oral fluid rapid HIV self-test associated with increased preference for using the test (post-assessment vs pre-assessment of opinion topics) were identified through multivariable regression models that adjusted for participant characteristics. Of the 1975 YMSM participants, the median age was 22 years (IQR 20-23); 19% were black, 36% Hispanic, and 45% white; and 18% previously used an oral fluid rapid HIV self-test. Although views about oral fluid rapid HIV self-testing test were favorable, few intended to use the test. Aspects about the oral fluid rapid HIV self-test associated with an increased preference for using the test were its privacy features, that it motivated getting tested more often or as soon as possible, and that it conferred feelings of more control over one's sexual health. Preferences for the oral fluid rapid HIV self-test were lower when costs were considered, yet these YMSM were much more interested in fingerstick blood sampling than oral fluid sampling rapid HIV self-testing. Despite the perceived advantages of the oral fluid rapid HIV self-test and favorable views about it by this population, prior use as well as future intention in using the test were low. Aspects about oral fluid rapid HIV self-testing identified as influential in this study might assist in interventions aimed to increase its use among this high HIV risk population as a means of encouraging regular HIV testing, identifying HIV-infected persons, and linking them to care. Although not yet commercially available in the United States, fingerstick rapid HIV self-testing might help motivate YMSM to be tested more than oral fluid rapid HIV self-testing. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Rheometrical experiments with monitoring of resistivity: for a better understanding of the solid-fluid transition in clayey landslides

NASA Astrophysics Data System (ADS)

Carrière, Simon; Bièvre, Grégory; Chambon, Guillaume; Jongmans, Denis; Lebourg, Thomas; Larose, Eric

2015-04-01

Landslides are natural and complex phenomena which affect all types of geological formations and present a large variety of size, morphology and displacements rates. Among these phenomena, flow-like events in clay-rich formations are particularly complex due to the unpredictable acceleration and fluidization that characterize them. Because of their suddenness, such landslides constitute serious threat for population living in these areas. The forecast and the understanding of these events has then been an active topic of research in the scientific community during the past decades. In that respect, rheometrical experiments in the laboratory bring some insight into the processes occurring during the solid-fluid transition. In creep tests, the evolution of the shear strain rate is measured under constant levels of shear stress, allowing to follow changes in apparent viscosity with time and to observe fluidization. Rheometrical oscillatory tests have been designed to capture the evolution of the elastic shear modulus G (and hence the shear wave velocity Vs) during these creep phases. Previous results have shown that Vs exhibits a drop at the solid-fluid transition, with complex time-dependent effects which could lead, under transient loading, to the occurrence of Vs variations prior to the transition. A complementary way to understand the processes is to measure the electrical resistivity during these rheometrical tests. This parameter, which depends on the water content and salinity, as well as on the amount of clay particles, could also exhibit some changes before or during the solid-fluid transition. For that purpose, the metallic plates of the rotational rheometer have been replaced by new ones made in an electrically insulating material (PVC) with a configuration of four inserted circular electrodes. Rheometrical tests made with this new apparatus provide similar rheological results. For the electrical tests, the geometrical factor has been computed using Finite Element modeling and has also been experimentally measured with water samples of varying and known resistivities. A difference of less than 1% was obtained between the two approaches. First resistivity results obtained on the Trièves clay (French Alps) show a progressive, weak but significant variation in resistivity (5-6 percent) during creep tests. The comparison between the creep and resistivity curves suggests that the resistivity decreases when the apparent viscosity increases. Further experiments are underway on different clays sampled on several flow-like landslides and would allow to have a better insight in the electrical response of such material during the solid-fluid transition.

Beryllium chemical speciation in elemental human biological fluids.

PubMed

Sutton, Mark; Burastero, Stephen R

2003-09-01

The understanding of beryllium chemistry in human body fluids is important for understanding the prevention and treatment of chronic beryllium disease. Thermodynamic modeling has traditionally been used to study environmental contaminant migration and rarely in the examination of metal (particularly beryllium) toxicology. In this work, a chemical thermodynamic speciation code (MINTEQA2) has been used to model and understand the chemistry of beryllium in simulated human biological fluids such as intracellular, interstitial, and plasma fluids, a number of airway surface fluids for patients with lung conditions, saliva, sweat, urine, bile, gastric juice, and pancreatic fluid. The results show that predicted beryllium solubility and speciation vary markedly between each simulated biological fluid. Formation of beryllium hydroxide and/or phosphate was observed in most of the modeled fluids, and results support the postulation that beryllium absorption in the gastrointestinal tract may be limited by the formation of beryllium phosphate solids. It is also postulated that beryllium is potentially 13% less soluble in the airway surface fluid of a patient with asthma when compared to a "normal" case. The results of this work, supported by experimental validation, can aid in the understanding of beryllium toxicology. Our results can potentially be applied to assessing the feasibility of biological monitoring or chelation treatment of beryllium body burden.

Mass transfer and fluid evolution in late-metamorphic veins, Rhenish Massif (Germany): insight from alteration geochemistry and fluid-mineral equilibria modeling

NASA Astrophysics Data System (ADS)

Marsala, Achille; Wagner, Thomas

2016-08-01

Element mobility and fluid-rock interaction related to the formation of late-metamorphic quartz veins have been studied by combination of mineral chemistry, whole-rock geochemistry, mass balance analysis and fluid-mineral equilibria modeling. The quartz veins are hosted by very low-grade metasedimentary rocks of the fold-and-thrust belt of the Rhenish Massif (Germany). The veins record two stages of evolution, a massive vein filling assemblage with elongate-blocky quartz, chlorite, apatite and albite, and a later open space filling assemblage with euhedral crystals of quartz, ankerite-dolomite and minor calcite and sulfides. Detailed mass balance analysis of an alteration profile adjacent to a representative quartz vein demonstrates that element mobility is restricted to the proximal zone. The most important element changes are gain of Ca, Fe, Mg, Mn, P and CO2, and loss of Si, K and Na. The data demonstrate that wall-rock carbonation is one of the main alteration features, whereas mobility of Si, K and Na are related to dissolution of quartz and destruction of detrital feldspar and muscovite. The whole-rock geochemical data, in conjunction with fluid composition data and pressure-temperature estimates, were used as input for fluid-mineral equilibria modeling in the system Si-Al-Fe-Mg-Ca-Na-K-C-S-O-H-B-F-Cl. Modeling involved calculation of rock-buffered fluid compositions over the temperature interval 100-500 °C, and reaction-path simulations where a rock-buffered high-temperature fluid reacts with fresh host-rocks at temperatures of 400, 300 and 200 °C. Calculated rock-buffered fluid compositions demonstrate that retrograde silica solubility is a strong driving force for quartz leaching in the temperature-pressure window of 380-450 °C and 0.5 kbar. These conditions overlap with the estimated temperatures for the initial stage of vein formation. Reaction-path models show that high-temperature alteration can produce the observed silica leaching, suggesting that fast advection of external hot fluids from deeper crustal levels was essential for the early stage of vein formation. Fluid advection must have occurred as multiple pulses, which allowed for periods of influx of fluids that leached quartz, alternating with periods of cooling and quartz precipitation in the veins. Reaction-path models at high temperatures (300-400 °C) do not produce carbonate alteration, whereas fluid-rock reaction at 200 °C produces carbonate alteration, consistent with the temperature estimates for the late-stage vein carbonate assemblage. Comparison between modeling results and geochemical data suggests that the observed alteration features are the product of fluid-rock reaction under conditions where the external fluid gradually cooled down and evolved with time. The results of this study highlight the importance of late-orogenic fluid migration for the formation of quartz vein arrays in fold-and-thrust belts.

Icodextrin reduces adhesion formation following gynecological surgery in rabbits

PubMed Central

Khani, Behnaz; Bahrami, Nahid; Mehrabian, Ferdous; Naderi Naeni, Hormoz

2011-01-01

Background: Adhesion is a common complication of gynecology surgery so different barrier agents and solutions have been used during these operations to separate and protect tissues from adhesion after surgery. Adept is one of these solutions that have been postulated to reduce the chance of adhesion following gynecolgy surgery. Objective: To evaluate the effect of 4% icodextrin in reducing adhesion formation in comparing with sterile water and human amniotic fluid in rabbits. Materials and Methods: In this prospective experimental study 30 white Newzealand female rabbits were selected and randomized in to three treatment groups. The rabbits were anesthetized and an abdominal incison was made, uterine horns were abrated with gauze until bleeding occurred. Before closing the abdomen, the traumatized area was irrigated either by 30cc of sterile water, 30cc of 4% Adept or 30cc of human amniotic fluid. The solutions were labeled only as solutions A (steriel water), B (icodextrin), or C (human amniotic fluid). On the seventh day after surgery, second laparotomy was performed to determine and compare adhesion formation in rabbits. Results: There was significant difference between mean score of adhesions in 4% icodextrin group (2.1±0.70) in comparison to sterile water group (10.4±0.60) and amniotic fluid group (8.7±0.84). But the difference between mean score of adhesions in amniotic fluid group in comparison to sterile water group was not significant (8.7±0.84) versus (10.4±0.60). Conclusion: The use of 4% icodextrin solution was more effective than human amniotic fluid and sterile water in reducing adhesion formation in a gynecological surgery model in rabbits PMID:26396562

Mathematical modeling and simulation analysis of hydraulic fracture propagation in three-layered poro-elastic media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moon, H.Y.; Advani, S.H.; Lee, T.S.

1992-11-01

Hydraulic fracturing plays a pivotal role in the enhancement of oil and gas production recovery from low permeability reservoirs. The process of hydraulic fracturing entails the generation of a fracture by pumping fluids blended with special chemicals and proppants into the payzone at high injection rates and pressures to extend and wedge fractures. The mathematical modeling of hydraulically induced fractures generally incorporates coupling between the formation elasticity, fracture fluid flow, and fracture mechanics equations governing the formation structural responses, fluid pressure profile, and fracture growth. Two allied unsymmetric elliptic fracture models are developed for fracture configuration evolutions in three-layered rockmore » formations. The first approach is based on a Lagrangian formulation incorporating pertinent energy components associated with the formation structural responses and fracture fluid flow. The second model is based on a generalized variational principle, introducing an energy rate related functional. These models initially simulate a penny-shaped fracture, which becomes elliptic if the crack tips encounters (upper and/or lower) barriers with differential reservoir properties (in situ stresses, 16 elastic moduli, and fracture toughness-contrasts and fluid leak-off characteristics). The energy rate component magnitudes are determined to interpret the governing hydraulic fracture mechanisms during fracture evolution. The variational principle is extended to study the phenomenon and consequences of fluid lag in fractures. Finally, parametric sensitivity and energy rate investigations to evaluate the roles of controllable hydraulic treatment variables and uncontrollable reservoir property characterization parameters are performed. The presented field applications demonstrate the overall capabilities of the developed models. These studies provide stimulation treatment guidelines for fracture configuration design, control, and optimization.« less

Cooling beyond the boundary value in supercritical fluids under vibration

NASA Astrophysics Data System (ADS)

Sharma, D.; Erriguible, A.; Amiroudine, S.

2017-12-01

Supercritical fluids when subjected to simultaneous quench and vibration have been known to cause various intriguing flow phenomena and instabilities depending on the relative direction of temperature gradient and vibration. Here we describe a surprising and interesting phenomenon wherein temperature in the fluid falls below the imposed boundary value when the walls are quenched and the direction of vibration is normal to the temperature gradient. We define these regions in the fluid as sink zones, because they act like sink for heat within the fluid domain. The formation of these zones is first explained using a one-dimensional (1D) analysis with acceleration in constant direction. Subsequently, the effect of various boundary conditions and the relative direction of the temperature gradient to acceleration are analyzed, highlighting the necessary conditions for the formation of sink zones. It is found that the effect of high compressibility and the action of self-weight (due to high acceleration) causes the temperature to change in the bulk besides the usual action of piston effect. This subsequently affects the overall temperature profile thereby leading to the formation of sink zones. Though the examined 1D cases differ from the current two-dimensional (2D) cases, owing to the direction of acceleration being normal as compared to parallel in case of former, the explanations pertaining to 1D cases are judiciously utilized to elucidate the formation of sink zones in 2D supercritical fluids subjected to thermal quench and vibrational acceleration. The appearance of sink zones is found to be dependent on several factors such as proximity to the critical point and acceleration. A surface three-dimensional plot illustrating the effect of these parameters on onset time of sink zones is presented to further substantiate these arguments.

Gehlenite and anorthite formation from fluid fly ash

NASA Astrophysics Data System (ADS)

Perná, Ivana; Šupová, Monika; Hanzlíček, Tomáš

2018-04-01

Fluid fly ash could be considered a waste, but, when well treated, it may also become a useful secondary source material. Its rather high content of calcium-containing phases along with thermally treated alumino-silicate residues resulting from coal combustion can lead to the formation of a stable system with newly formatted phases. The high temperature destroys the clay lattice and activates a new configuration of aluminum ions, changing their coordination to oxygen. The effect is accompanied by changes in charge in the surroundings, which are compensated for by calcium ions. The higher the temperature of the fluid ash treatment, the more pronounced the appearance of gehlenite and anorthite in the final mass. Both are natural materials and, together with mullite and anhydrite, they could ensure safety and protection even if exposed to open fire of up to 1150 °C.

Microthermometry of enargite-hosted fluid inclusions from the Lepanto, Philippines, high-sulfidation Cu sbnd Au deposit

NASA Astrophysics Data System (ADS)

Mancano, D. P.; Campbell, A. R.

1995-10-01

The spatial relation between porphyry and high-sulfidation epithermal deposits is particularly well revealed in the Mankayan mineral district of northern Luzon, Philippines, where the Lepanto high-sulfidation Cu sbnd Au deposit lies over and adjacent to the Far Southeast (FSE) porphyry Cu sbnd Au deposit. Consequently, a study was undertaken to characterize the fluids responsible for epithermal mineralization in this environment. The ore stage at Lepanto consists of enargite-luzonite (Cu 3AsS 4), pyrite, tennantite-tetrahedrite, and chalcopyrite. Infrared petrography of the enargite reveals variable transparency, with growth banding and twinning visible in euhedral specimens. Two phase (liquid > vapor) fluid inclusions occur as primary and secondary types ranging from <1 to 80 micrometers in length, with tabular, cylindrical, or oval shapes. Homogenization temperatures ( Th) of fluid inclusions in enargite were measured from within the lateral (3.0 km) and vertical (0.5 km) extent of the enargite mineralization. These values show a cooling trend toward the northwest, away from the area over the porphyry deposit, with average Th ranging from 285°C (proximal) to 166°C (distal). Ice melting temperatures ( Tm) were measured using a cycling technique, as ice was usually not visible in frozen inclusions. Apparent salinities range from 4.5 to 0.2 eq. wt% NaCl, with samples from the margins of the deposit showing a general decrease in apparent salinity with lower Th. Secondary fluid inclusions in quartz phenocrysts tend to have a higher average Th and lower apparent salinities compared to enargite-hosted inclusion fluids from the same locations. Several samples of pyrite are also transparent to IR radiation, and show internal features such as growth banding, and in one instance a two phase (liquid > vapor) fluid inclusion. This inclusion yielded a salinity of 1.2 eq. wt% NaCl. There is a large discrepancy in Th and apparent salinities between the enargite mineralization and the subjacent porphyry deposit despite contemporaneous formation, suggesting that the hot, (>500°C) hypersaline, magmatic brines associated with porphyry mineralization did not directly ascend to the elevation of the enargite deposit. However, absorbtion of magmatic vapors into overlying meteoric water may have created the mineralizing fluid of the Lepanto deposit. As this liquid moved to the northwest along the Lepanto fault, it was cooled and diluted by mixing with groundwater, resulting in enargite deposition.

Experimental Evidence of Volcanic Earthquakes Induced by Different Fluid Types

NASA Astrophysics Data System (ADS)

Clarke, J. A.; Adam, L.; Sarout, J.; van Wijk, K.; Dautriat, J. D.; Kennedy, B.

2017-12-01

Low Frequency volcanic seismicity has long been associated with resonance in fluid-filled cracks or conduits driven by pressure perturbations at depth. In volcano monitoring, fluid movement, fracturing and the conduit geometry are interpreted based on field observations, laboratory experiments, and numerical models. Fluids in a volcanic environment include gasses, brine and magmas with different viscosities. Magma viscosity is a key influence on eruptive behaviour. For example, increasing magma viscosity is known to favour explosive eruptions. How different fluids affect volcano seismicity is not well understood. Here, we explore the effects of fluid type on volcano seismic signals. Frequency content in the signal, frequency of the events, source mechanism and quality factor are studied. We simulate volcano tectonic (fracturing) and volcano seismic (fluid movement) signatures in a controlled laboratory environment using a range of rock samples, fluid types and pressure conditions. The viscosity of the fluids spans six orders of magnitude, representing realistic volcanic fluids. Microseismicity is generated by venting pressurised fluids through pre-generated fracture networks in cylindrical rock core samples and detected by an array of 18 ultrasonic transducers. We fracture samples of two lithologies: 1) low porosity impermeable granite samples and 2) a permeable volcanic ash tuff sample. Permeability and porosity in the granites are due to a fracture network, while in the tuff a high porosity matrix ( 40 %) and a fracture network interact. The fluids used are nitrogen gas, water, and mixtures of water and glycerol. We generate and detect a myriad of seismic event types, some of which resemble well-known families of volcano-tectonic, low-frequency, hybrid and tremor-type seismicity. Samples with fluids of lower density and viscosity generate a higher number of seismic events. We will present an integrated analysis of the event types, frequency content, source locations and mechanisms. In addition, we explore the importance of seismic wave attenuation by studying the relationship between wave path and event frequency content.

Microstructures and Crystallographic Misorientation in Experimentally Deformed Natural Quartz Single Crystals

NASA Astrophysics Data System (ADS)

Thust, Anja; Heilbronner, Renée.; Stünitz, Holger

2010-05-01

Samples of natural milky quartz were deformed in a Griggs deformation apparatus at different confining pressures (700 MPa, 1000 MPa, 1500 MPa), with constant displacement rates of 1 * 10-6s-1, axial strains of 3 - 19%, and at a temperature of 900° C. The single crystal starting material contains a large number of H2O-rich fluid inclusions. Directly adjacent to the fluid inclusions the crystal is essentially dry (50-150H/106Si, determined by FTIR). The samples were cored from a narrow zone of constant 'milkyness' (i.e. same density of fluid inclusions) in a large single crystal in two different orientations (1) normal to one of the prism planes (⊥{m} orientation) and (2) 45° to and to (O+ orientation).During attaining of the experimental P and T conditions, numerous fluid inclusions decrepitate by cracking. Rapid crack healing produces regions of very small fluid inclusions ('wet' quartz domains). Only these regions are subsequently deformed by dislocation glide, dry quartz domains without cracking and decrepitation of fluid inclusions remain undeformed. Sample strain is not sufficient to cause recrystallization, so that deformation is restricted to dislocation glide. In experiments at lower temperatures (800, 700° C) or at lower strain rate (10-5s-1) there is abundant cracking and semi-brittle deformation, indicating that 900° C, (10-6s-1) represents the lower temperature end of crystal plastic deformation in these single crystals. Peak strengths (at 900° C) range between 150 and 250 MPa for most samples of both orientations. There is a trend of decreasing strength with increasing confining pressure, as described by Kronenberg and Tullis (1984) for quartzites, but the large variation in strength due to inhomogeneous sample strain precludes a definite analysis of the strength/pressure dependence in our single crystals. In the deformed samples, we can distinguish a number of microstructures and inferred different slip systems. In both orientations, deformation lamellae with a high optical relief appear in the usual sub-basal orientation; often they are associated with 'fluid inclusions trails', cracks or en echelon arrays. In ⊥{m} orientation, conjugate misorientation bands sub-parallel to the prism planes can be observed. The barreled shape of the samples can be explained by prism glide. Unfortunately, since prism glide does not affect the c-axis orientation it cannot be recognized on a c-axis orientation image. Nevertheless, changes in the c-axis orientation are observed locally, indicating either the activity of an additional slip system or a different deformation process (not specified yet). In O+ orientation, we observe the formation of internally kinked shear bands. They are up to 100 μm wide and oriented at α 90° w/r to the host c-axis, slightly oblique to the sense of shear. The width of the kinked domains is 20-40 μm and the average misorientation (β) is 5° . The dispersion of c-axis orientation with synthetic rotation of the c-axis is evidence of basal glide. References: Kronenberg, A.K. & Tullis, J. (1984): Flow strength of quartz aggregates: grain size and pressure effects due to hydrolytic weakening. JGR Vol. 89, 4281-4281.

Understanding physical rock properties and their relation to fluid-rock interactions under supercritical conditions

NASA Astrophysics Data System (ADS)

Kummerow, Juliane; Raab, Siegfried; Meyer, Romain

2017-04-01

The electrical conductivity of rocks is, in addition to lithological factors (mineralogy, porosity) and physical parameters (temperature, pressure) sensitive to the nature of pore fluids (phase, salinity), and thus may be an indicative measure for fluid-rock interactions. Especially near the critical point, which is at 374.21° C and 22.12 MPa for pure water, the physico-chemical properties of aqueous fluids change dramatically and mass transfer and diffusion-controlled chemical reactivity are enhanced, which in turn leads to the formation of element depletion/ enrichment patterns or cause mineral dissolution. At the same time, the reduction of the dielectric constant of water promotes ion association and consequently mineral precipitation. All this cause changes in the electrical conductivity of geothermal fluids and may have considerable effects on the porosity and hydraulic properties of the rocks with which they are in contact. In order to study the impact of fluid-rock interactions on the physical properties of fluids and rocks in near- and supercritical geological settings in more detail, in the framework of the EU-funded project "IMAGE" (Integrated Methods for Advanced Geothermal Exploration) hydraulic and electrical properties of rock cores from different active and exhumed geothermal areas on Iceland were measured up to supercritical conditions (Tmax = 380° C, pfluid = 23 MPa) during long-term (2-3 weeks) flow-through experiments in an internally heated gas pressure vessel at a maximum confining pressure of 42 MPa. In a second flow-through facility both the intrinsic T-dependent electrical fluid properties as well as the effect of mineral dissolution/ precipitation on the fluid conductivity were measured for increasing temperatures in a range of 24 - 422° C at a constant fluid pressure of 31 MPa. Petro- and fluid physical measurements were supplemented by a number of additional tests, comprising microstructural investigations as well as the chemical analysis of fluid samples, which were taken at every temperature level. Both physical and chemical data indicate only slight fluid-rock interactions at T < 250° C and the increase in bulk conductivity is most probably dominated by a T-dependence of the surface conductance. At higher temperatures, the decreasing fluid density causes the decrease of dielectric constant, which in turn leads to the precipitation of minerals due to a promoted association between oppositely charged ions. This is intensified at the critical point, indicated by a sharp decrease in conductivity, when regarding pure fluids. The opposite was observed in experiments, where fluid-solid interaction was allowed. In this case, the conductivity of the bulk system has increased within seconds nearly by factor 7. This points to a massive release of charge carriers due to an extensive and spontaneous increase in rock solubility, what counterbalances the effect of mineral precipitation. Moreover, the permanent oscillation of conductivities at supercritical conditions may indicate a dynamic interplay of ion depletion by mineral precipitation and the input of new charge carriers due to mineral dissolution. Regarding the permeability we can resolve the influence of mineral precipitation only, which is indicated by a decrease in rock permeability by about 5 % after the sample was exposed to supercritical conditions for 4 hours. Especially, for Si a continuous increase of ion concentration in the fluid samples is revealed for increasing temperatures, indicating a beginning mineral dissolution above 150° C. At near-critical conditions also Al and Pb as well as the rare earth elements (REE) are more intensively dissolved. From SEM analyses it is apparent that the alteration of the solid material is most effective where fresh fluid is continuously flowing around the solid, while stagnant fluids led to a much less pervasive alteration of the material. In this case, solid dissolution seems to slow down considerably or even comes to an end, what can be explained by the adjustment of a chemical equilibrium and the stabilisation of the reaction front.

Process of forming compounds using reverse micelle or reverse microemulsion systems

DOEpatents

Linehan, John C.; Fulton, John L.; Bean, Roger M.

1998-01-01

The present invention is directed to a process for producing a nanometer-sized metal compound. The process comprises forming a reverse micelle or reverse microemulsion system comprising a polar fluid in a non-polar or low-polarity fluid. A first reactant comprising a multi-component, water-soluble metal compound is introduced into the polar fluid in a non-polar or low-polarity fluid. This first reactant can be introduced into the reverse micelle or reverse microemulsion system during formation thereof or subsequent to the formation of the reverse micelle or microemulsion system. The water-soluble metal compound is then reacted in the reverse micelle or reverse microemulsion system to form the nanometer-sized metal compound. The nanometer-sized metal compound is then precipitated from the reverse micelle or reverse microemulsion system.

Tourmaline's record of Alpine metamorphism and segregation formation in the Pfitsch Formation, Western Tauern Window

NASA Astrophysics Data System (ADS)

Berryman, E. J.; Kutzschbach, M.; Trumbull, R. B.; Meixner, A.; van Hinsberg, V.; Kasemann, S.; Franz, G.

2017-12-01

Tourmaline, a common accessory mineral in the metasedimentary units of the Pfitsch Formation in the Western Tauern Window, Eastern Alps, records the variation in fluid composition and B mobilization during Alpine metamorphism. These post-Variscan metasediments are part of the Subpenninic nappes, the former European distal margin, and experienced peak metamorphic conditions of 550°C, 1.0 GPa. In all investigated units, tourmaline is predominantly dravitic, with high Fe contents. Charge balance calculations combined with Fe-Mg and Fe-Al variation suggest a significant proportion of ferric iron. Tourmaline's composition reflects its host rock assemblage, with the relative predominance of Fe-Mg or Fe-Al exchange in tourmaline from different units corresponding to the presence of biotite/chlorite or muscovite, respectively. Boron content and correspondingly tourmaline abundance is highest in a 25 m thick unit of feldspathic gneiss ( 20-200 ppm B). The abundance and size of the tourmaline crystals increases near coarse-grained quartzofeldspathic segregations ( 1200 ppm B), reflecting the mobilization and concentration of B by the metamorphic fluid. Tourmaline crystals near segregations have up to three growth zones, recording pro- ( 350-500°C, 0.7-1.0 GPa) and retrograde (400°C, 0.2 GPa) growth. They show the largest amount of compositional variation, covering the range of compositional space represented by tourmaline occurring away from segregations. Tourmaline near segregations has the highest inferred ferric iron content, which decreases across growth zones, potentially reflecting the gradual reduction of the fluid during metamorphism. Whole rock δ11B values (-15 to -34‰) vary with the heaviest values found near B-rich segregations, and the lightest values in B-depleted samples. This correlation reflects the preferential mobilization of 11B towards the segregations. Isotopic zonation of individual tourmaline crystals with -11‰ in their cores and -20‰ in their rims suggests continuous volatilization and fractionation of B by a 10B-rich precursor mineral (e.g. mica) during prograde mobilization and redistribution of B within the Pfitsch Formation.

Development of the laboratory prototype "CavyPool" for assessing treatments and materials for swimming pools.

PubMed

Valeriani, F; Gianfranceschi, G; Vitali, M; Protano, C; Romano Spica, V

2017-01-01

Hygiene and surveillance in swimming pools are established by WHO Guidelines and national laws. Progress in water management and pool construction is revolutionizing the field, introducing new materials, systems, disinfection procedures or monitoring markers. Innovation advances challenge the upgrading of safety and quality in pools and the appropriate implementation of guidelines. In order to provide a device for laboratory test, a prototype was realized and applied to study and compare swimming pool materials and treatments. A pool scale-model was engineered and evaluated by computational fluid dynamics algorithms. An automated real time monitoring assured steady state. Critical control points along the water circuit were made accessible to allow the placing of different biocides or water sampling. Simulations were safely performed in a standard hood. Materials for pool surfaces and pipelines were evaluated for biofilm formation under different disinfection conditions. Adherent microorganisms were assayed by mfDNA analysis using real time PCR. The prototype reached the steady state within 5-25 hours under different conditions, showing chemical, physical and fluid-dynamic stability. A method was optimized for testing materials showing their different response to biofilm induction. Several innovative PVC samples displayed highest resistance to bacterial adhesion. A device and method was developed for testing swimming pool hygienic parameters in laboratory. It allowed to test materials for pools hygiene and maintenance, including biofilm formation. It can be applied to simulate contaminations under different water treatments or disinfection strategies. It may support technical decisions and help policymakers in acquiring evidences for comparing or validating innovative solutions.

Accessing SAFOD data products: Downhole measurements, physical samples and long-term monitoring

NASA Astrophysics Data System (ADS)

Weiland, C.; Zoback, M.; Hickman, S. H.; Ellsworth, W. L.

2005-12-01

Many different types of data were collected during SAFOD Phases 1 and 2 (2004-2005) as part of the National Science Foundation's EarthScope program as well as from the SAFOD Pilot Hole, drilled in 2002 and funded by the International Continental Drilling Program (ICDP). Both SAFOD and the SAFOD Pilot Hole are being conducted as a close collaboration between NSF, the U.S. Geological Survey and the ICDP. SAFOD data products include cuttings, core and fluid samples; borehole geophysical measurements; and strain, tilt, and seismic recordings from the multilevel SAFOD borehole monitoring instruments. As with all elements of EarthScope, these data (and samples) are openly available to members of the scientific and educational communities. This paper presents the acquisition, storage and distribution plan for SAFOD data products. Washed and unwashed drill cuttings and mud samples were collected during Phases 1 and 2, along with three spot cores at depths of 1.5, 2.5, and 3.1 km. A total of 52 side-wall cores were also collected in the open-hole interval between 2.5 and 3.1 km depth. The primary coring effort will occur during Phase 3 (2007), when we will continuously core up to four, 250-m-long multilaterals directly within and adjacent to the San Andreas Fault Zone. Drill cuttings, core, and fluid samples from all three Phases of SAFOD drilling are being curated under carefully controlled conditions at the Integrated Ocean Drilling Program (IODP) Gulf Coast Repository in College Station, Texas. Photos of all physical samples and a downloadable sample request form are available on the ICDP website (http://www.icdp-online.de/sites/sanandreas/index/index.html). A suite of downhole geophysical measurements was conducted during the first two Phases of SAFOD drilling, as well as during drilling of the SAFOD Pilot Hole. These data include density, resistivity, porosity, seismic and borehole image logs and are also available via the ICDP website. The SAFOD monitoring program includes fiber-optic strain, tilt, seismic and fluid-pressure recording instruments. Seismic data from the Pilot Hole array are now available in SEED format from the Northern California Earthquake Data Center (http://quake.geo.berkeley.edu/safod/). The strain and tilt instruments are still undergoing testing and quality assurance, and these data will be available through the same web site as soon as possible. Lastly, two terabytes of unprocessed (SEG-2 format) data from a two-week deployment of an 80-level seismic array during April/May 2005 by Paulsson Geophysical Services, Inc. are now available via the IRIS data center (http://www.iris.edu/data/data.htm). Drilling parameters include real-time descriptions of drill cuttings mineralogy, drilling mud properties, and mechanical data related to the drilling process and are available via the ICDP web site. Current status reports on SAFOD drilling, borehole measurements, sampling, and monitoring instrumentation will continue to be available from the EarthScope web site (http://www.earthscope.org).

Formation of magmatic brine lenses via focussed fluid-flow beneath volcanoes

NASA Astrophysics Data System (ADS)

Afanasyev, Andrey; Blundy, Jon; Melnik, Oleg; Sparks, Steve

2018-03-01

Many active or dormant volcanoes show regions of high electrical conductivity at depths of a few kilometres beneath the edifice. We explore the possibility that these regions represent lenses of high-salinity brine separated from a single-phase magmatic fluid containing H2O and NaCl. Since chloride-bearing fluids are highly conductive and have an exceptional capacity to transport metals, these regions can be an indication of an active hydrothermal ore-formation beneath volcanoes. To investigate this possibility we have performed hydrodynamic simulations of magma degassing into permeable rock. In our models the magma source is located at 7 km depth and the fluid salinity approximates that expected for fluids released from typical arc magmas. Our model differs from previous models of a similar process because it is (a) axisymmetric and (b) includes a static high-permeability pathway that links the magma source to the surface. This pathway simulates the presence of a volcanic conduit and/or plexus of feeder dykes that are typical of most volcanic systems. The presence of the conduit leads to a number of important hydrodynamic consequences, not observed in previous models. Importantly, we show that an annular brine lens capped by crystallised halite is likely to form above an actively degassing sub-volcanic magma body and can persist for more than 250 kyr after degassing ceases. Parametric analysis shows that brine lenses are more prevalent when the fluid is released at temperatures above the wet granite solidus, when magmatic fluid salinity is high, and when the high-permeability pathway is narrow. The calculated depth, form and electrical conductivity of our modelled system shares many features with published magnetotelluric images of volcano subsurfaces. The formation and persistence of sub-volcanic brine lenses has implications for geothermal systems and hydrothermal ore formation, although these features are not explored in the presented model.

Inorganic Geochemistry of Flowback Water from the Montney Formation: Potential Sources of Elevated Ion Concentrations

NASA Astrophysics Data System (ADS)

Owen, J.; Bustin, R.

2016-12-01

An inorganic geochemical analysis was conducted on flowback water from hydraulically fractured oil and gas wells of the Montney Formation of varying thermal maturity and stratigraphy in the Western Canadian Sedimentary Basin. The results of this study provide insight into potential sources of the elevated ion concentrations and can be used to assist with wastewater management and blending of water for reuse. Samples were obtained from 31 wells across the Montney and include wells completed in the lower, middle, and upper units. Selected fluid samples from each well were analyzed using ICP-OES, ICP-MS, and IC. Oxygen and hydrogen isotope analysis was performed using a liquid-water isotope analyzer. The flowback waters are classified as sodium-chloride type. In addition to Na and Cl, calcium, potassium, magnesium, and strontium are elevated and increase during the flowback period. Barium, iron, and lithium are also elevated at some locations. The early flowback water chemistry varies within the formation: higher initial TDS values of approximately 50,000mg/L in Upper Montney flowback water relative to the initial TDS from both Middle and Lower Montney wells (<25,000mg/L and <15,000mg/L, respectively). However, overall, the maximum TDS attained later in the flowback period does not show a consistent stratigraphic trend (range: 55,000 - 130,000mg/L) except for one region in the Middle Montney where the maximum TDS remains consistently lower than other areas (<50,000mg/L). Barium is notable in Montney flowback due to its high variability, with the lowest concentrations occurring in Middle Montney flowback and the highest in Lower Montney flowback. Comparing closely spaced wells completed on the same pad and in the same zone, the flowback waters generally have similar ion concentrations and consistent ion ratios. The increasing ion concentrations as well as the stable water isotopes support mixing between the hydraulic fracturing fluid, which has relatively low ion concentrations, and more saline connate formation water. Geochemical modeling indicates the ion concentrations in the flowback water are a complex product of mineral precipitation/dissolution, ion exchange with the reservoir, geochemistry of the connate water and water saturation of the reservoir.

An improved method for permeability estimation of the bioclastic limestone reservoir based on NMR data

NASA Astrophysics Data System (ADS)

Ge, Xinmin; Fan, Yiren; Liu, Jianyu; Zhang, Li; Han, Yujiao; Xing, Donghui

2017-10-01

Permeability is an important parameter in formation evaluation since it controls the fluid transportation of porous rocks. However, it is challengeable to compute the permeability of bioclastic limestone reservoirs by conventional methods linking petrophysical and geophysical data, due to the complex pore distributions. A new method is presented to estimate the permeability based on laboratory and downhole nuclear magnetic resonance (NMR) measurements. We divide the pore space into four intervals by the inflection points between the pore radius and the transversal relaxation time. Relationships between permeability and percentages of different pore intervals are investigated to investigate influential factors on the fluid transportation. Furthermore, an empirical model, which takes into account of the pore size distributions, is presented to compute the permeability. 212 core samples in our case show that the accuracy of permeability calculation is improved from 0.542 (SDR model), 0.507 (TIM model), 0.455 (conventional porosity-permeability regressions) to 0.803. To enhance the precision of downhole application of the new model, we developed a fluid correction algorithm to construct the water spectrum of in-situ NMR data, aiming to eliminate the influence of oil on the magnetization. The result reveals that permeability is positively correlated with percentages of mega-pores and macro-pores, but negatively correlated with the percentage of micro-pores. Poor correlation is observed between permeability and the percentage of meso-pores. NMR magnetizations and T2 spectrums after the fluid correction agree well with laboratory results for samples saturated with water. Field application indicates that the improved method provides better performance than conventional models such as Schlumberger-Doll Research equation, Timur-Coates equation, and porosity-permeability regressions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bass, Jay D.

This project is aimed at experimental characterization of the sound velocities, equations of state (EOS), and derived physical and chemical properties of aqueous solutions and carbon dioxide at extreme pressure and temperature conditions relevant to processes occurring in the interior of the Earth. Chemical transport, phase changes (including melting), fluid-solid reactions, and formation of magmatic liquids at convergent plat boundaries are a key motivation for this project. Research in this area has long been limited by the extreme experimental challenges and lack of data under the appropriate pressure-temperature (P-T) conditions. The vast majority of studies of aqueous geochemistry relevant tomore » terrestrial problems of fluid-rock interactions have been conducted at 0.3 GPa or less, and the widely used Helgeson-Kirkham-Flowers equation of state for aqueous species is applicable only at ~ < 0.5 GPa. These limits are unfortunate because fluid flow and reactions plays a central role in many deeper environments. Recent efforts including our own, have resulted in new experimental techniques that now make it possible to investigate properties of homogeneous and heterogeneous equilibria involving aqueous species and minerals over a much broader range of pressure and temperature appropriate for deep crustal and upper mantle processes involving water-rich fluids. We carried out 1) Brillouin scattering measurements of the equations of state and molar volume of water and carbon dioxide to over 10 GPa and 870K using precise resistance heating of samples under pressure in the diamond anvil cell, and 2) the phase diagrams of the water and CO2, and 3) Exploring new experimental approaches, including CO2 laser heating of samples in a diamond cell, to measurements of sound velocities, EOS, and phase relations by Brillouin scattering to far greater pressures and temperatures.« less

Measurement and reduction of micro-bubble formation in high-viscosity fluids

NASA Astrophysics Data System (ADS)

Tom, Glenn; Liu, Wei

2012-03-01

Gases at high drive pressure can initially dissolve into the fluids used in lithography and other critical processes during the fabrication of integrated circuits. In the low pressure portion of the dispense train, the dissolved gases can revert to bubbles. These bubbles can: 1. Affect the compressibility of the working fluid and change the flow characteristics of the dispense heads which require frequent re-tuning of the coating tools. 2. Contribute to defect formation if the bubbles are trapped on the surface of the wafer. Photosensitive Polyimides (PI) have high viscosities (1000 to 20,000 cP). Because of the high viscosity, high-powered, expensive pumps are needed to effectively remove the fluid from its container. Suction from the pump filling cycle easily causes cavitation, which can create flow rate variability, and micro-bubble formation. It is a common practice to apply pressure to the PI resists to minimize cavitation in the pump. The trade-off to this practice is the entrainment (dissolution) of the drive gas into the resist and the risk of micro-bubbles forming later in the dispense train. In the current study, ATMI measured the effects of two methods of pressure dispense from the container on the amount of gas entrained in a viscous fluid: (1) indirect pressure dispense and (2) direct pressure dispense. The main analytical method employed to measure the amount of dissolved gases is a gas chromatograph (GC), which can measure the concentration of gases dissolved in a volatile fluid. It is not suitable to measure gases in low volatility fluids. The new test method developed, however, is capable of measuring dissolved gases in low volatility fluids.

Fluid-Rock Characterization and Interactions in NMR Well Logging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirasaki, George J.; Mohanty, Kishore K.

2003-02-10

The objective of this project was to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity.

Dark Solitons in High Velocity Waveguide Polariton Fluids.

PubMed

Walker, P M; Tinkler, L; Royall, B; Skryabin, D V; Farrer, I; Ritchie, D A; Skolnick, M S; Krizhanovskii, D N

2017-09-01

We study exciton-polariton nonlinear optical fluids in the high momentum waveguide regime for the first time. We demonstrate the formation of dark solitons with the expected dependence of width on fluid density for both main classes of soliton-forming fluid defects. The results are well described by numerical modeling of the fluid propagation. We deduce a continuous wave nonlinearity more than ten times that on picosecond time scales, arising due to interaction with the exciton reservoir.

Reducing or stopping the uncontrolled flow of fluid such as oil from a well

DOEpatents

Hermes, Robert E

2014-02-18

The uncontrolled flow of fluid from an oil or gas well may be reduced or stopped by injecting a composition including 2-cyanoacrylate ester monomer into the fluid stream. Injection of the monomer results in a rapid, perhaps instantaneous, polymerization of the monomer within the flow stream of the fluid. This polymerization results in formation of a solid plug that reduces or stops the flow of additional fluid from the well.

Isoflurane in contrast to propofol promotes fluid extravasation during cardiopulmonary bypass in pigs.

PubMed

Brekke, Hege Kristin; Hammersborg, Stig Morten; Lundemoen, Steinar; Mongstad, Arve; Kvalheim, Venny Lise; Haugen, Oddbjørn; Husby, Paul

2013-10-01

A highly positive intraoperative fluid balance should be prevented as it negatively impacts patient outcome. Analysis of volume-kinetics has identified an increase in interstitial fluid volume after crystalloid fluid loading during isoflurane anesthesia. Isoflurane has also been associated with postoperative hypoxemia and may be associated with an increase in alveolar epithelial permeability, edema formation, and hindered oxygen exchange. In this article, the authors compare fluid extravasation rates before and during cardiopulmonary bypass (CPB) with isoflurane- versus propofol-based anesthesia. Fourteen pigs underwent 2 h of tepid CPB with propofol (P-group; n = 7) or isoflurane anesthesia (I-group; n = 7). Fluid requirements, plasma volume, colloid osmotic pressures in plasma and interstitial fluid, hematocrit levels, and total tissue water content were recorded, and fluid extravasation rates calculated. Fluid extravasation rates increased in the I-group from the pre-CPB level of 0.27 (0.13) to 0.92 (0.36) ml·kg·min, but remained essentially unchanged in the P-group with significant between-group differences during CPB (pb = 0.002). The results are supported by corresponding changes in interstitial colloid osmotic pressure and total tissue water content. During CPB, isoflurane, in contrast to propofol, significantly contributes to a general increase in fluid shifts from the intravascular to the interstitial space with edema formation and a possible negative impact on postoperative organ function.

Porcine reproductive and respiratory syndrome virus (PRRSV) surveillance using pre-weaning oral fluid samples detects circulation of wild-type PRRSV.

PubMed

Kittawornrat, Apisit; Panyasing, Yaowalak; Goodell, Christa; Wang, Chong; Gauger, Phillip; Harmon, Karen; Rauh, Rolf; Desfresne, Luc; Levis, Ian; Zimmerman, Jeffrey

2014-01-31

Oral fluid samples collected from litters of piglets (n=600) one day prior to weaning were evaluated as a method to surveil for porcine reproductive and respiratory syndrome virus (PRRSV) infections in four sow herds of approximately 12,500 sow each. Serum samples from the litters' dam (n=600) were included for comparison. All four herds were endemically infected with PRRSV and all sows had been vaccinated ≥ 2 times with PRRSV modified-live virus vaccines. After all specimens had been collected, samples were randomized and assayed by PRRSV real-time reverse transcription polymerase chain reaction (RT-qPCR) and four PRRSV antibody ELISA assays (IgM, IgA, IgG, and Commercial Kit). All sow serum samples were negative by PRRSV RT-qPCR, but 9 of 600 oral fluid samples tested positive at two laboratories. Open reading frame 5 (ORF5) sequencing of 2 of the 9 positive oral fluid samples identified wild-type viruses as the source of the infection. A comparison of antibody responses in RT-qPCR positive vs. negative oral fluid samples showed significantly higher IgG S/P ratios in RT-qPCR-positive oral fluid samples (mean S/P 3.46 vs. 2.36; p=0.02). Likewise, sow serum samples from RT-qPCR-positive litter oral fluid samples showed significantly higher serum IgG (mean S/P 1.73 vs. 0.98; p<0.001) and Commercial Kit (mean S/P 1.97 vs. 0.98; p<0.001) S/P ratios. Overall, the study showed that pre-weaning litter oral fluid samples could provide an efficient and sensitive approach to surveil for PRRSV in infected, vaccinated, or presumed-negative pig breeding herds. Copyright © 2014 Elsevier B.V. All rights reserved.

Composition of fluid inclusions in Permian salt beds, Palo Duro Basin, Texas, U.S.A.

USGS Publications Warehouse

Roedder, E.; d'Angelo, W. M.; Dorrzapf, A.F.; Aruscavage, P. J.

1987-01-01

Several methods have been developed and used to extract and chemically analyze the two major types of fluid inclusions in bedded salt from the Palo Duro Basin, Texas. Data on the ratio K: Ca: Mg were obtained on a few of the clouds of tiny inclusions in "chevron" salt, representing the brines from which the salt originally crystallized. Much more complete quantitative data (Na, K, Ca, Mg, Sr, Cl, SO4 and Br) were obtained on ??? 120 individual "large" (mostly ???500 ??m on an edge, i.e., ??? ??? 1.6 ?? 10-4 g) inclusions in recrystallized salt. These latter fluids have a wide range of compositions, even in a given piece of core, indicating that fluids of grossly different composition were present in these salt beds during the several (?) stages of recrystallization. The analytical results indicating very large inter-and intra-sample chemical variation verify the conclusion reached earlier, from petrography and microthermometry, that the inclusion fluids in salt and their solutes are generally polygenetic. The diversity in composition stems from the combination of a variety of sources for the fluids (Permian sea, meteoric, and groundwater, as well as later migrating ground-, formation, or meteoric waters of unknown age), and a variety of subsequent geochemical processes of dissolution, precipitation and rock-water interaction. The compositional data are frequently ambiguous but do provide constraints and may eventually yield a coherent history of the events that produced these beds. Such an understanding of the past history of the evaporite sequence of the Palo Duro Basin should help in predicting the future role of the fluids in the salt if a nuclear waste repository is sited there. ?? 1987.

Measurement of Clozapine, Norclozapine, and Amisulpride in Plasma and in Oral Fluid Obtained Using 2 Different Sampling Systems.

PubMed

Fisher, Danielle S; Beyer, Chad; van Schalkwyk, Gerrit; Seedat, Soraya; Flanagan, Robert J

2017-04-01

There is a poor correlation between total concentrations of proton-accepting compounds (most basic drugs) in unstimulated oral fluid and in plasma. The aim of this study was to compare clozapine, norclozapine, and amisulpride concentrations in plasma and in oral fluid collected using commercially available collection devices [Thermo Fisher Scientific Oral-Eze and Greiner Bio-One (GBO)]. Oral-Eze and GBO samples and plasma were collected in that order from patients prescribed clozapine. Analyte concentrations were measured by liquid chromatography-tandem mass spectrometry. There were 112 participants [96 men, aged (median, range) 47 (21-65) years and 16 women, aged 44 (21-65) years]: 74 participants provided 2 sets of samples and 7 provided 3 sets (overall 2 GBO samples not collected). Twenty-three patients were co-prescribed amisulpride, of whom 17 provided 2 sets of samples and 1 provided 3 sets. The median (range) oral fluid within the GBO samples was 52 (13%-86%). Nonadherence to clozapine was identified in all 3 samples in one instance. After correction for oral fluid content, analyte concentrations in the GBO and Oral-Eze samples were poorly correlated with plasma clozapine and norclozapine (R = 0.57-0.63) and plasma amisulpride (R = 0.65-0.72). Analyte concentrations in the 2 sets of oral fluid samples were likewise poorly correlated (R = 0.68-0.84). Mean (SD) plasma clozapine and norclozapine were 0.60 (0.46) and 0.25 (0.21) mg/L, respectively. Mean clozapine and norclozapine concentrations in the 2 sets of oral fluid samples were similar to those in plasma (0.9-1.8 times higher), that is, approximately 2- to 3-fold higher than those in unstimulated oral fluid. The mean (±SD) amisulpride concentrations (microgram per liter) in plasma (446 ± 297) and in the Oral-Eze samples (501 ± 461) were comparable and much higher than those in the GBO samples (233 ± 318). Oral fluid collected using either the GBO system or the Oral-Eze system cannot be used for quantitative clozapine and/or amisulpride therapeutic drug monitoring.

Oral fluid samples used for PRRSV acclimatization program and sow performance monitoring in endemic PRRS-positive farms.

PubMed

Woonwong, Yonlayong; Kedkovid, Roongtham; Arunorat, Jirapat; Sirisereewan, Chaitawat; Nedumpun, Teerawut; Poonsuk, Korakrit; Panyasing, Yaowalak; Poolperm, Pariwat; Boonsoongnern, Alongkot; Thanawongnuwech, Roongroje

2018-02-01

An effective gilt acclimatization program is one of the most important management strategies for controlling porcine reproductive and respiratory syndrome virus (PRRSV) infection. Recently, oral fluid samples have been used as alternative diagnostic samples for various swine diseases. This study utilized oral fluids for PRRSV monitoring during the gilt acclimatization period in PRRSV endemic farms. The study was performed in two selected commercial breeding herds (farm A and farm B). PRRSV RNA and PRRSV-specific antibodies were monitored using oral fluid and serum samples. Sow performance parameters related to PRRSV infection were recorded and assessed. After PRRSV exposure during acclimatization, viral RNA was demonstrated in oral fluids from 1 to 10 weeks post-exposure (WPE). PRRSV RNA was detected in serum at 1 and 4 WPE in farm A and at 1, 4, 8, and 12 WPE in farm B. Prolonged viremia of gilts from farm B was possibly due to re-infection (within the herd) and later, reproductive problems were found in the breeding herd. The correlation of PRRSV RNA concentration in oral fluids and serum was evident. The S/P ratio values of PRRSV antibodies in oral fluid samples were higher and had similar patterns of antibody responses to the serum samples. The results suggest that the use of oral fluid samples for PRRSV monitoring during gilt acclimatization in endemic farms is effective, convenient, practical, and economical and would be most beneficial when used with other parameters.

Magnetic particle translation as a surrogate measure for synovial fluid mechanics.

PubMed

Shah, Yash Y; Maldonado-Camargo, Lorena; Patel, Neal S; Biedrzycki, Adam H; Yarmola, Elena G; Dobson, Jon; Rinaldi, Carlos; Allen, Kyle D

2017-07-26

The mechanics of synovial fluid vary with disease progression, but are difficult to quantify quickly in a clinical setting due to small sample volumes. In this study, a novel technique to measure synovial fluid mechanics using magnetic nanoparticles is introduced. Briefly, microspheres embedded with superparamagnetic iron oxide nanoparticles, termed magnetic particles, are distributed through a 100μL synovial fluid sample. Then, a permanent magnet inside a protective sheath is inserted into the synovial fluid sample. Magnetic particles translate toward the permanent magnet and the percentage of magnetic particles collected by the magnet in a given time can be related to synovial fluid viscosity. To validate this relationship, magnetic particle translation was demonstrated in three phases. First, magnetic particle translation was assessed in glycerol solutions with known viscosities, demonstrating that as fluid viscosity increased, magnetic particle translation decreased. Next, the relationship between magnetic particle translation and synovial fluid viscosity was assessed using bovine synovial fluid that was progressively degenerated via ultrasonication. Here, particle collection in a given amount of time increased as fluid degenerated, demonstrating that the relationship between particle collection and fluid mechanics holds in non-Newtonian synovial fluid. Finally, magnetic particle translation was used to assess differences between healthy and OA affected joints in equine synovial fluid. Here, particle collection in a given time was higher in OA joints relative to healthy horses (p<0.001). Combined, these data demonstrate potential viability of magnetic particle translation in a clinical setting to evaluate synovial fluid mechanics in limited volumes of synovial fluid sample. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 146.32 - Construction requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... during drillings. (c) Where the injection zone is a formation which is naturally water-bearing the... characteristics of the formation fluids. (d) Where the injection formation is not a water-bearing formation, the... Section 146.32 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...

Serpentinisation and fluid flow associated with a detachment fault in Tasna OCT, South-east Switzerland

NASA Astrophysics Data System (ADS)

Engström, A. V.; Skelton, A. D.

2003-04-01

The well-studied Iberia Abyssal Plain (ODP legs 149 and 173) is a non-volcanic passive margin where continental crust and oceanic crust are separated by a “mantle window” composed of serpentinised peridotites. The exhumation of the mantle at this transitional zone is under debate and several models involving detachment faulting, shear zones or magmatic intrusions have been proposed to explain the formation of the ocean-continent transition (OCT). The mechanical behaviour of serpentinite, with its low density, strength and permeability, and the timing of the serpentinisation process in relation to the exhumation, are crucial parameters in understanding non-volcanic rifting processes. Beneath Iberia Abyssal Plain, sampling is restricted to ocean ridges, the recovery is very poor and in addition, drillcores only give one-dimensional data, implicitly any data is not statistically well represented. However, there are several land analogues of past ocean-continent margins which give excellent opportunities to study the timing and evolution of fluids and serpentinisation in several dimensions. The Tasna OCT is a “mantle window” situated in the Swiss Alps displaying exhumed mantle (serpentinised peridotite) in contact with basement rocks or sediments. For this study several sampling profiles have been conducted across the mantle boundary. Field observations together with ignition experiments and thin section analyses indicate that the degree of serpentinisation is not continously increasing with depth as may be expected. In contrast, high serpentinite contents were recorded at the top of the mantle sequence as well as deeper down. The general pattern of serpentinisation shows “saw tooth” geometry as the content fluctuate from high to low and back to higher values again. This implies that the fluid flow has been channeled. Oxygen isotope studies from the Iberia margin (Skelton and Valley 2000) show deformation channeled fluid flow. Several heavily eroded sections in the Tasna OCT may very well correspond with the postulated shear zones in the Iberia margin localizing the fluid.

Gas chromatographic-mass spectrometric investigation of n-alkanes and carboxylic acids in bottom sediments of the northern Caspian Sea

NASA Astrophysics Data System (ADS)

Kenzhegaliev, Akimgali; Zhumagaliev, Sagat; Kenzhegalieva, Dina; Orazbayev, Batyr

2018-03-01

Prior to the start of experimental oil production in the Kashagan field (northern part of the Caspian Sea), n-alkanes and carboxylic acids contained in samples obtained from bottom sediments in the area of artificial island "D" were investigated by gas chromatography-mass spectrometry. Concentrations of 10 n-alkanes (composed of C10-C13, C15-C20) and 11 carboxylic acids (composed of C6-C12, C14-C16) were identified and measured. Concentrations of individual alkanes and carboxylic acids in bottom sediments of the various samples varied between 0.001 ÷ 0.88 μg/g and 0.001 ÷ 1.94 μg/g, respectively. Mass spectra, in particular the M+ molecular ion peak and the most intense peaks of fragment ions, are given. The present study illustrates the stability of molecular ions to electronic ionisation and the main fragment ions to the total ion current and shows that the initial fragmentation of alkanes implies radical cleavage of C2H5 rather than CH3. All aliphatic monocarboxylic acids studied were characterised by McLafferty rearrangement leading to the formation of F4 cation-radical with m/z 60 and F3 cation-radical with m/z 88 in the case of ethylhexanoic acid. The formation of oxonium ions presents another important aspect of acid fragmentation. Using mass numbers of oxonium ions and rearrangement ions allows determination of the substitution character in α- and β- C atoms. The essence of our approach is to estimate the infiltration of hydrocarbon fluids from the enclosing formation into sea water, comprising an analysis of derivatives of organic compounds in bottom sediments. Thus, concentrations of derived organic molecules can serve as a basis for estimates of the depth at which hydrocarbon fluids leak, i.e., to serve as an auxiliary technique in the search for hydrocarbon deposits and to repair well leaks.

Surface sampling concentration and reaction probe

DOEpatents

Van Berkel, Gary J; Elnaggar, Mariam S

2013-07-16

A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

CHRONOLOGICAL CONSTRAINTS ON FLUID CIRCULATION IN MESOZOIC FORMATIONS OF THE EASTERN PART OF THE PARIS BASIN INFERRED FROM U-Pb DATING OF SECONDARY INFILLING CARBONATES

NASA Astrophysics Data System (ADS)

Pisapia, C.; Deschamps, P.; Hamelin, B.; Buschaert, S.

2009-12-01

The French agency for nuclear waste management (ANDRA) developed an Underground Research Laboratory in the Mesozoic formations of Eastern part of the Paris Basin (France) to assess the feasibility of a high-level radioactive wastes repository in sedimentary formations. The target host formation is a low-porosity detrital argillite (Callovo-Oxfordian) embedded between two shelf limestones formations (of Bajocian-Bathonian and Oxfordian-Kimmeridgian ages). These formations are affected by fracture networks, likely inherited mainly from the Eocene-Oligocene extension tectonics, also responsible of the Rhine graben formation in the same region. The limestones have very low permeability, the primary and secondary porosity being infilled by secondary carbonated minerals. The inter-particle porosity is filled with euhedral calcite spar cements. Similarly, macro-cavities and connected micro-fractures are almost sealed by euhedral calcite. Geochemical evidences (δ18O) suggest that the secondary carbonates likely derived from a common parent fluid (Buschaert et al., 2004, Appl. Geochem. (19) 1201-1215p). This late carbonated precipitation phase is responsible for the intense cementation of the limestone formations and bears witness of a major phase of fluids circulation that marked the late diagenetic evolution of the system. Knowledge of the chronology of the different precipitation phases of secondary minerals is thus of critical importance in order to determine the past hydrological conditions of the geological site. The aim of this study is to provide chronological constraints on the secondary carbonate mineral precipitation using U/Th and U/Pb methods. Analyses are performed on millimeter to centimeter scale secondary calcites collected within fractures outcropping in the regional fault zone of Gondrecourt and in cores from the ANDRA exploration-drilling program. Preliminary U-Th analyses obtained on secondary carbonates from surface fractures infillings yield secular equilibrium composition, indicating that the precipitation phase was older than 650 ky. U-Pb measurements were performed on a VG sector Thermal Ionization Mass Spectrometer (TIMS) using a 205Pb-236U-233U-229Th spike. Pb contents are generally very low, between 3 and 20 ppb, while U contents are more variable, leading to μ = 238U/204Pb up to ~600. Sub-samples with high μ show radiogenic 206Pb/204Pb ratio, but at this stage isochrons generally show high scatter. These U-Pb data however are consistent with an Eocene-Oligocene period for the late carbonates precipitation phase. We will discuss the different processes that may be responsible for these errorchrons (i.e. heterogeneities in the initial isotopic composition; multi-stage growth) as well as the chronological constraints that can be drawn from these data.

An LES-PBE-PDF approach for modeling particle formation in turbulent reacting flows

NASA Astrophysics Data System (ADS)

Sewerin, Fabian; Rigopoulos, Stelios

2017-10-01

Many chemical and environmental processes involve the formation of a polydispersed particulate phase in a turbulent carrier flow. Frequently, the immersed particles are characterized by an intrinsic property such as the particle size, and the distribution of this property across a sample population is taken as an indicator for the quality of the particulate product or its environmental impact. In the present article, we propose a comprehensive model and an efficient numerical solution scheme for predicting the evolution of the property distribution associated with a polydispersed particulate phase forming in a turbulent reacting flow. Here, the particulate phase is described in terms of the particle number density whose evolution in both physical and particle property space is governed by the population balance equation (PBE). Based on the concept of large eddy simulation (LES), we augment the existing LES-transported probability density function (PDF) approach for fluid phase scalars by the particle number density and obtain a modeled evolution equation for the filtered PDF associated with the instantaneous fluid composition and particle property distribution. This LES-PBE-PDF approach allows us to predict the LES-filtered fluid composition and particle property distribution at each spatial location and point in time without any restriction on the chemical or particle formation kinetics. In view of a numerical solution, we apply the method of Eulerian stochastic fields, invoking an explicit adaptive grid technique in order to discretize the stochastic field equation for the number density in particle property space. In this way, sharp moving features of the particle property distribution can be accurately resolved at a significantly reduced computational cost. As a test case, we consider the condensation of an aerosol in a developed turbulent mixing layer. Our investigation not only demonstrates the predictive capabilities of the LES-PBE-PDF model but also indicates the computational efficiency of the numerical solution scheme.

Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

PubMed

Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

2013-01-01

Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ(13)Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate.

Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

PubMed Central

Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

2013-01-01

Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0–100 MPa) and temperature (0–70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ13Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate. PMID:24348470

Carbon dioxide sequestration induced mineral precipitation healing of fractured reservoir seals

NASA Astrophysics Data System (ADS)

Welch, N.; Crawshaw, J.

2017-12-01

Initial experiments and the thermodynaic basis for carbon dioxide sequestration induced mineral precipitation healing of fractures through reservoir seals will be presented. The basis of this work is the potential exists for the dissolution of reservoir host rock formation carbonate minerals in the acidified injection front of CO2 during sequestration or EOR. This enriched brine and the bulk CO2 phase will then flow through the reservoir until contact with the reservoir seal. At this point any fractures present in the reservoir seal will be the preferential flow path for the bulk CO2 phase as well as the acidified brine front. These fractures would currently be filled with non-acidified brine saturated in seal formation brine. When the acidifeid brine from the host formation and the cap rock brine mix there is the potential for minerals to fall out of solution, and for these precipitated minerals to decrease or entirely cut off the fluid flow through the fractures present in a reservoir seal. Initial equilibrium simulations performed using the PHREEQC1 database drived from the PHREEQE2 database are used to show the favorable conditions under which this mineral precipitation can occurs. Bench scale fluid mixing experiments were then performed to determine the kinetics of the mineral precipitation process, and determine the progress of future experiemnts involving fluid flow within fractured anhydrite reservoir seal samples. 1Parkhurst, D.L., and Appelo, C.A.J., 2013, Description of input and examples for PHREEQC version 3—A computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations: U.S. Geological Survey Techniques and Methods, book 6, chap. A43, 497 p., available only at https://pubs.usgs.gov/tm/06/a43/. 2Parkhurst, David L., Donald C. Thorstenson, and L. Niel Plummer. PHREEQE: a computer program for geochemical calculations. No. 80-96. US Geological Survey, Water Resources Division,, 1980.

Constraints of gas venting activity for the interstitial water geochemistry at the shallow gas hydrate site, eastern margin of the Japan Sea; results from high resolution time-series fluid sampling by OsmoSampler

NASA Astrophysics Data System (ADS)

Owari, S.; Tomaru, H.; Matsumoto, R.

2016-12-01

We have conducted ROV researches in the eastern margin of the Japan Sea where active gas venting and outcropping of gas hydrates were observed near the seafloor and have found the strength and location of venting had changed within a few days. These observations indicate the seafloor environments with the shallow gas hydrate system could have changed for short period compared to a geological time scale. We have applied a long-term osmotic fluid sampling system "OsmoSampler" on the active gas hydrate system for one year in order to document how the gas venting and gas hydrate activity have changed the geochemical environments near the seafloor. All the major ion concentrations in the interstitial water show synchronous increase and decrease repeatedly in three to five days, reflecting the incorporation and release of fresh water in gas hydrates in response to the gas concentration change near the sampling site. Dissolved methane concentration increases rapidly and excessively (over several mM) in the first 40 days corresponding to the active gas venting. The increases of methane concentration are often associated with high ion concentration during high water pressure period, indicating excess gas release from shallow gas pockets. Contrarily, enhanced gas hydrate growth may plug the fluid-gas paths in shallow sediment, reducing gas hydrate formation due to the decrease of methane flux. This study was conducted under the commission from AIST as a part of the methane hydrate research project funded by METI (the Ministry of Economy, Trade and Industry, Japan).

Lateral Organization of Lipids in Multi-component Liposomes

NASA Astrophysics Data System (ADS)

Ramachandran, Sanoop; Laradji, Mohamed; Sunil Kumar, P. B.

2009-04-01

Inspite of the fluid nature and low elastic modulus, membranes play a crucial role in maintaining the structural integrity of the cell. Recent experiments have challenged the passive nature of the membrane as proposed by the classical fluid mosaic model. Experiments indicate that biomembranes of eukaryotic cells may be laterally organized into small nanoscopic domains, called rafts, which are rich in sphingomyelin and cholesterol. It is largely believed that this in-plane organization is essential for a variety of physiological functions such as signaling, recruitment of specific proteins and endocytosis. However, elucidation of the fundamental issues including the mechanisms leading to the formation of lipid rafts, their stability, and their size remain difficult. This has reiterated the importance of understanding the equilibrium phase behavior and the kinetics of fluid multicomponent lipid membranes before attempts are made to find the effects of more complex mechanisms that may be involved in the formation and stability of lipid rafts. Current increase in interest in the domain formation in multicomponent membranes also stems from the experiments demonstrating fluid-fluid coexistence in mixtures of lipids and cholesterol and the success of several computational models in predicting their behavior. Here we review time dependent Ginzburg Landau model, dynamical triangulation Monte Carlo, and dissipative particle dynamics which are some of the methods that are commonly employed.

The evolution of volcano-hosted geothermal systems based on deep wells from Karaha-Telaga Bodas, Indonesia

USGS Publications Warehouse

Moore, J.N.; Allis, R.G.; Nemcok, M.; Powell, T.S.; Bruton, C.J.; Wannamaker, P.E.; Raharjo, I.B.; Norman, D.I.

2008-01-01

Temperature and pressure surveys, fluid samples, and petrologic analyses of rock samples from deep drill holes at the Karaha - Telaga Bodas geothermal field on the volcanic ridge extending northward from Galunggung Volcano, West Java, have provided a unique opportunity to characterize the evolution of an active volcano-hosted geothermal system. Wells up to 3 km in depth have encountered temperatures as high as 353??C and a weakly altered granodiorite that intruded to within 2 to 3 km of the surface. The intrusion is shallowest beneath the southern end of the field where an acid lake overlies a nearly vertical low resistivity structure (<10 ohm-m) defined by magnetotelluric measurements. This structure is interpreted to represent a vapor-dominated chimney that provides a pathway to the surface for magmatic gases. Four distinct hydrothermal mineral assemblages document the evolution of the geothermal system and the transition from liquid- to vapor-dominated conditions. The earliest assemblage represents the initial liquid-dominated system generated during emplacement of the granodiorite between 5910 ?? 76 and 4200 ?? 150 y BP. Tourmaline, biotite, actinolite, epidote and clay minerals were deposited contemporaneously at progressively greater distances from the intrusive contact (assemblage 1). At 4200 ?? 150 y BP, flank collapse and the formation of the volcano's crater, Kawah Galunggung, resulted in catastrophic decompression and boiling of the hydrothermal fluids. This event initiated development of the modern vapor-dominated regime. Chalcedony and then quartz were deposited as the early low salinity liquids boiled (assemblage 2). Both vapor- and liquid-rich fluid inclusions were trapped in the quartz crystals. Liquid-rich fluid inclusions from the southern part of the field record salinities ranging from 0 to 26 weight percent NaCl- CaCl2 equivalent and locally contain fluorite daughter crystals. We suggest, based on temperature-salinity relationships and evidence of boiling, that these fluids were progressively concentrated as steam was lost from the system. However, mixing with fluids derived from the underlying intrusion or generated during the formation of acid SO4 water on the vapor-dominated chimney margins could have contributed to the observed salinities. As pressures declined, CO2- and SO4-rich steam-heated water drained downward, depositing anhydrite and calcite (assemblage 3) in the fractures, limiting further recharge. Fluid inclusions with salinities up to 31 weight percent NaCl equivalent were trapped in these minerals as the descending water vaporized. The final assemblage is represented by precipitates of NaCl, KCl and FeClx deposited on rock surfaces in portions of the vapor-dominated zone that boiled dry. Vapor-dominated conditions extend over a distance of at least 10 km and to depths below sea level. Deep wells drilled into the underlying liquid-dominated reservoir in the northern and central part of the volcanic ridge produce low salinity fluids representing recent recharge of meteoric and steam-heated water. The evolution of volcanic-hosted vapor-dominated geothermal systems can be described by a five stage model. Stage 1 involves the formation of an over-pressured liquid-dominated geothermal system soon after magmatic intrusion. In Stages 2 and 3, pressures progressively decrease, and a curtain of steam-heated water surrounding a magmatic vapor-dominated chimney at 350??C and 14 ?? 2 MPa develops. The relatively low pressure near the base of the chimney causes liquid inflow adjacent to the intrusion and the development of a secondary marginal vapor-dominated zone. In Stage 4, the magmatic vapor discharge from the intrusion becomes small, vapor pressure declines, and the secondary vapor-dominated zone expands above the intrusion. In Stage 5, the vapor-dominated zone floods because heat from the intrusion is insufficient to boil all liquid inflow. A more common, liquid-dominated volcanic-hosted system the

PGE and Re-Os Isotope Behaviour in a Subduction-Modified Mantle Wedge: A Fresh Look into the Peridotites from the Ulten Zone, Eastern Alps

NASA Astrophysics Data System (ADS)

Aulbach, S.; Braga, R.; Gudelius, D.; Prelevic, D.; Meisel, T. C.

2015-12-01

Peridotites in the upper Austroalpine Ulten zone (Eastern Italy) sample the subduction-modified Variscan mantle wedge. Metasomatism of peridotites during four stages of mantle wedge evolution includes: (1) Intrusion of alkaline melts from an inner, subduction-modified wedge and cryptic enrichment of spinel lherzolites (SL); (2) Reaction with siliceous crustal melts after pressure increase, generating coarse-grained garnet amphibole peridotites (GAP); (3) Crystallisation of abundant amphibole (± apatite and dolomite) from residual hydrous fluids during and/or after peak metamorphism recorded by fine-grained GAP; [4] Subsequent influx of crustal fluids, causing retrograde formation of spinel chlorite amphibole peridotites (SAP) [1-5]. SL and coarse GAP are apparently more fertile, whereas fine GAP and SAP retain the most depleted major-element characteristics. Overall, samples fall on partial melting trends consistent with extraction of low degrees of melt (F≤0.15) at 2-1 GPa. SL and coarse GAP have ±flat PGE patterns normalised to Primitive Upper Mantle (PUM), or show small decreases or increases from compatible to incompatible PGE. This suggests retention of primary sulphide liquid at low degrees of melting, during which PGE concentrations are little fractionated [6]. Indeed, broad positive correlations between the PGE suggest a common host, likely sulphide, observed in the samples as assemblages of pn ± po and cpy. Most fine-GAP share these patterns, indicating robustness against massive hydrous fluid influx, while Os/Ir > PUM argue against strong Os scavenging by highly oxidising hydrous fluids. Nevertheless, elevated Ru/IrPUM in a subgroup of samples may indicate a role for spinel addition under oxidising conditions. Most samples have 187Os/188Os >PUM, despite sub-PUM Re/Os, which requires addition of, or isotopic equilibration with, 187Os-rich crustal components, most likely via the precipitation of metasomatic sulphide. [1] Nimis and Morten (2000) J Geodyn 30: 93-115; [2] Rampone and Morten (2001) J Petrol 42: 207-219; [3] Tumiati et al. (2003) Earth Planet Sci Lett 210: 509-526; [4] Sapienza et al. (2009) Contrib Mineral Petrol 158: 401-420; [5] Scambelluri et al. (2006) Contrib Mineral Petrol 151: 372-394; [6] Mungall and Brenan (2014) Geochim Cosmochim Acta 125: 265-289.

Multistage deformation of Au-quartz veins (Laurieras, French Massif Central): evidence for late gold introduction from microstructural, isotopic and fluid inclusion studies

NASA Astrophysics Data System (ADS)

Essarraj, S.; Boiron, M.-C.; Cathelineau, M.; Fourcade, S.

2001-07-01

The relative chronology of fluid migration, quartz and Au-deposition in a silicified fault from the main Au-district (Laurieras, St Yrieix district) from northern French Massif Central has been determined from microstructural, fluid inclusion, isotopic and ore mineral evidences. Three main stages of fluid circulation, microfracturing and quartz crystallization, and ore deposition were distinguished on the basis of textural relationships and the pressure, temperature and composition of the palaeo-fluids: (1) a series of early fluid events was responsible for the localized drainage of retrograde metamorphic fluids along the main fault and the subsequent sealing by milky and microcrystalline quartz preceeded the main Au-ore stages. Early fluids were aqueous-carbonic, trapped under lithostatic to sublithostatic pressures at temperatures in the range 350-500°C. Subsequently, several types of microstructures were developed in the early quartz matrix. (2) NS microfractures filled by clear quartz, arsenopyrite and boulangerite (I) contain significant refractory gold concentrations. Clear quartz formed from aqueous-carbonic fluids of lower densities than those of the earlier fluids. Significant pressure drops, down to pressures around 55 MPa were responsible for a local immiscibility of the aqueous-carbonic fluids at temperatures of 340±20°C. (3) The main ore stage is characterized by the formation of dense sets of sub-vertical (EW) microfractures, healed fluid inclusion planes in quartz, and filled by ore minerals (native gold, galena and boulangerite II) when they crosscut earlier sulfides. The fluids are aqueous with low and decreasing salinity, and probable trapping temperatures around 230°C. Isotopic data, obtained on microfissured quartz, indicate these dilute aqueous fluids may be considered as meteoric waters that deeply infiltrated the crust. Late microfissuring of a mesothermal quartz vein, originally barren (only with pyrite and arsenopyrite), appears to be the main factor controlling gold enrichment. It can be related to late Hercynian deformational stages, disconnected from the early fault formation and silicification. These late stages which affected the Hercynian basement during its uplift, are of critical importance for the formation of Au-ores. We concluded that this type of Au-ore formed under rather shallow conditions, is distinct from those generally described in most mesothermal Au-veins.

Influence of film dimensions on film droplet formation.

PubMed

Holmgren, Helene; Ljungström, Evert

2012-02-01

Aerosol particles may be generated from rupturing liquid films through a droplet formation mechanism. The present work was undertaken with the aim to throw some light on the influence of film dimensions on droplet formation with possible consequences for exhaled breath aerosol formation. The film droplet formation process was mimicked by using a purpose-built device, where fluid films were spanned across holes of known diameters. As the films burst, droplets were formed and the number and size distributions of the resulting droplets were determined. No general relation could be found between hole diameter and the number of droplets generated per unit surface area of fluid film. Averaged over all film sizes, a higher surface tension yielded higher concentrations of droplets. Surface tension did not influence the resulting droplet diameter, but it was found that smaller films generated smaller droplets. This study shows that small fluid films generate droplets as efficiently as large films, and that droplets may well be generated from films with diameters below 1 mm. This has implications for the formation of film droplets from reopening of closed airways because human terminal bronchioles are of similar dimensions. Thus, the results provide support for the earlier proposed mechanism where reopening of closed airways is one origin of exhaled particles.

A study on inclusion formation mechanism in alpha-LiIO sub 3 crystals

NASA Technical Reports Server (NTRS)

Chen, W. C.; Yan, S. L.; Jia, S. Q.; Du, S. Y.

1985-01-01

The spatial distribution of inclusions in alpha-LiIO3 crystals by means of an argon laser beam scanning technique is studied. The effects of crystal dimensions and solution fluid flow on the inclusion formation in the alpha-LiIO3 crystals were observed. It was further shown that the fluid flow plays an important role in the formation of inclusions. The results obtained were further applied and verified by growing a perfect alpha-LiIO3 single crystal. An experimental foundation for further theoretical studies on the causes of inclusions may be provided.

The search for and analysis of direct samples of early Solar System aqueous fluids.

PubMed

Zolensky, Michael E; Bodnar, Robert J; Yurimoto, Hisayoshi; Itoh, Shoichi; Fries, Marc; Steele, Andrew; Chan, Queenie H-S; Tsuchiyama, Akira; Kebukawa, Yoko; Ito, Motoo

2017-05-28

We describe the current state of the search for direct, surviving samples of early, inner Solar System fluids-fluid inclusions in meteorites. Meteoritic aqueous fluid inclusions are not rare, but they are very tiny and their characterization is at the state of the art for most analytical techniques. Meteoritic fluid inclusions offer us a unique opportunity to study early Solar System brines in the laboratory. Inclusion-by-inclusion analyses of the trapped fluids in carefully selected samples will, in the immediate future, provide us detailed information on the evolution of fluids as they interacted with anhydrous solid materials. Thus, real data can replace calculated fluid compositions in thermochemical calculations of the evolution of water and aqueous reactions in comets, asteroids, moons and the terrestrial planets.This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'. © 2017 The Author(s).

Hydrothermal alteration and Cu–Ni–PGE mobilization in the charnockitic rocks of the footwall of the South Kawishiwi intrusion, Duluth Complex, USA

PubMed Central

Benkó, Zsolt; Mogessie, Aberra; Molnár, Ferenc; Krenn, Kurt; Poulson, Simon R.; Hauck, Steven; Severson, Mark; Arehart, Greg B.

2015-01-01

In the Neoarchean (~ 2.7 Ga) contact metamorphosed charnockitic footwall of the Mesoproterosoic (1.1 Ga) South Kawishiwi intrusion of the Duluth Complex, the primary metamorphic mineral assemblage and Cu–Ni–PGE sulfide mineralization is overprinted by an actinolite + chlorite + cummingtonite + prehnite + pumpellyite + quartz + calcite hydrothermal mineral assemblage along 2–3 cm thick veins. In calcite, hosted by the hydrothermal alteration zones and in a single recrystallized quartz porphyroblast, four different fluid inclusion assemblages are documented; the composition of these fluid inclusions provide p–T conditions of the fluid flow, and helps to define the origin of the fluids and evaluate their role in the remobilization and reprecipitation of the primary metamorphic sulfide assemblage. Pure CO2 fluid inclusions were found as early inclusions in recrystallized quartz porphyroblast. These inclusions may have been trapped during the recrystallization of the quartz during the contact metamorphism of the footwall charnockite in the footwall of the SKI. The estimated trapping pressure (1.6–2.0 kbar) and temperature (810–920 °C) conditions correspond to estimates based on felsic veins in the basal zones of the South Kawishiwi intrusion. Fluid inclusion assemblages with CO2–H2O–NaCl and CH4–N2–H2O–NaCl compositions found in this study along healed microfractures in the recrystallized quartz porphyroblast establish the heterogeneous state of the fluids during entrapment. The estimated trapping pressure and temperature conditions (240–650 bar and 120–150 °C for CO2–H2O–NaCl inclusions and 315–360 bar and 145–165 °C for CH4–N2–H2O–NaCl inclusions) are significantly lower than the p–T conditions (> 700 °C and 1.6–2 kbar) during the contact metamorphism, indicating that this fluid flow might not be related to the cooling of the Duluth Complex and its contact aureole. The presence of chalcopyrite inclusions in these fluid inclusions and in the trails of these fluid inclusion assemblages confirms that at least on local scale these fluids played a role in base metal remobilization. No evidences have been observed for PGE remobilization and transport in the samples. The source of the carbonic phase in the carbonic assemblages (CO2; CH4) could be the graphite, present in the metasedimentary hornfelsed inclusions in the basal zones of the South Kawishiwi intrusion. The hydrothermal veins in the charnockite can be characterized by an actinolite + cummingtonite + chlorite + prehnite + pumpellyite + calcite (I–II) + quartz mineral assemblage. Chlorite thermometry yields temperatures around 276–308 °C during the earliest phase of the fluid flow. In the late calcite (II) phase, high salinity (21.6–28.8 NaCl + CaCl2 equiv. wt.%), low temperature (90–160 °C), primary aqueous inclusions were found. Chalcopyrite (± sphalerite ± millerite), replacing and intersecting the early hydrothermal phases, are associated to the late calcite (II) phase. The composition of the formational fluids in the Canadian Shield is comparable with the composition of the studied fluid inclusions. This suggests that the composition of the fluids did not change in the past 2 Ga and base metal remobilization by formational fluids could have taken place any time after the formation of the South Kawishiwi intrusion. Sulfur isotope studies carried out on the primary metamorphic (δ34S = 7.4–8.9‰) and the hydrothermal sulfide mineral assemblage (δ34S = 5.5–5.7‰) proves, that during the hydrothermal fluid flow the primary metamorphic ores were remobilized. PMID:26594080

A transition in the viscous fingering instability in miscible fluids

NASA Astrophysics Data System (ADS)

Videbaek, Thomas; Nagel, Sidney R.

2017-11-01

The viscous fingering instability in a quasi-two dimensional Hele-Shaw cell is an example of complex structure formation from benign initial conditions. When the invading fluid has the lesser viscosity, the interface between the two fluids is unstable to finger formation. Here, we study the instability between pairs of miscible fluids in a circular cell with fluid injected at its center. As the injection rate is decreased, diffusion will smooth out the discontinuity in the gap-averaged viscosity at the interface between the fluids. At high injection rates (i.e., high Péclet number, Pe), fingering is associated with three-dimensional structure within the gap between the confining plates. On lowering Pe, we find a sharp transition in the finger morphology at a critical value, Pec (ηi /ηo) 1 / 2 , with ηi (ηo) being the viscosity of the inner (outer) fluid; at this point, the width of the fingers jumps, the length of the fingers shrinks towards zero and the three-dimensional structure goes from half filling to fully filling the gap. Thus, by controlling the viscosity contrast at the interface, one can alter and even completely suppress the instability.

Boiling point measurement of a small amount of brake fluid by thermocouple and its application.

PubMed

Mogami, Kazunari

2002-09-01

This study describes a new method for measuring the boiling point of a small amount of brake fluid using a thermocouple and a pear shaped flask. The boiling point of brake fluid was directly measured with an accuracy that was within approximately 3 C of that determined by the Japanese Industrial Standards method, even though the sample volume was only a few milliliters. The method was applied to measure the boiling points of brake fluid samples from automobiles. It was clear that the boiling points of brake fluid from some automobiles dropped to approximately 140 C from about 230 C, and that one of the samples from the wheel cylinder was approximately 45 C lower than brake fluid from the reserve tank. It is essential to take samples from the wheel cylinder, as this is most easily subjected to heating.

Next-generation confirmatory disease diagnostics

NASA Astrophysics Data System (ADS)

Lin, Robert; Gerver, Rachel; Karns, Kelly; Apori, Akwasi A.; Denisin, Aleksandra K.; Herr, Amy E.

2014-06-01

Microfluidic tools are advancing capabilities in screening diagnostics for use in near-patient settings. Here, we review three case studies to illustrate the flexibility and analytical power offered by microanalytical tools. We first overview a near-patient tool for detection of protein markers found in cerebrospinal fluid (CSF), as a means to identify the presence of cerebrospinal fluid in nasal mucous - an indication that CSF is leaking into the nasal cavity. Microfluidic design allowed integration of several up-stream preparatory steps and rapid, specific completion of the human CSF protein assay. Second, we overview a tear fluid based assay for lactoferrin, a protein produced in the lacrimal gland, then secreted into tear fluid. Tear Lf is a putative biomarker for primary SS. A critical contribution of this and related work being measurement of Lf, even in light of well-known and significant matrix interactions and losses during the tear fluid collection and preparation. Lastly, we review a microfluidic barcode platform that enables rapid measurement of multiple infectious disease biomarkers in human sera. The assay presents a new approach to multiplexed biomarker detection, yet in a simple straight microchannel - thus providing a streamlined, simplified microanalytical platform, as is relevant to robust operation in diagnostic settings. We view microfluidic design and analytical chemistry as the basis for emerging, sophisticated assays that will advance not just screening diagnostic technology, but confirmatory assays, sample preparation and handling, and thus introduction and utilization of new biomarkers and assay formats.

Supercritical Fuel Pyrolysis

DTIC Science & Technology

2010-05-30

supercritical fluids . These temperatures and pressures will also cause the fuel to undergo pyrolytic reactions, which have the potential of forming...With regard to physical properties, supercritical fluids have highly variable densities, no surface tension, and transport properties (i.e., mass...effects in supercritical fluids , often affecting chemical reaction pathways by facilitating the formation of certain transition states [6]. Because

Paramagnetic Attraction of Impurity-Helium Solids

NASA Technical Reports Server (NTRS)

Bernard, E. P.; Boltnev, R. E.; Khmelenko, V. V.; Lee, D. M.

2003-01-01

Impurity-helium solids are formed when a mixture of impurity and helium gases enters a volume of superfluid helium. Typical choices of impurity gas are hydrogen deuteride, deuterium, nitrogen, neon and argon, or a mixture of these. These solids consist of individual impurity atoms and molecules as well as clusters of impurity atoms and molecules covered with layers of solidified helium. The clusters have an imperfect crystalline structure and diameters ranging up to 90 angstroms, depending somewhat on the choice of impurity. Immediately following formation the clusters aggregate into loosely connected porous solids that are submerged in and completely permeated by the liquid helium. Im-He solids are extremely effective at stabilizing high concentrations of free radicals, which can be introduced by applying a high power RF dis- charge to the impurity gas mixture just before it strikes the super fluid helium. Average concentrations of 10(exp 19) nitrogen atoms/cc and 5 x 10(exp 18) deuterium atoms/cc can be achieved this way. It shows a typical sample formed from a mixture of atomic and molecular hydrogen and deuterium. It shows typical sample formed from atomic and molecular nitrogen. Much of the stability of Im-He solids is attributed to their very large surface area to volume ratio and their permeation by super fluid helium. Heat resulting from a chance meeting and recombination of free radicals is quickly dissipated by the super fluid helium instead of thermally promoting the diffusion of other nearby free radicals.

An approach to modeling coupled thermal-hydraulic-chemical processes in geothermal systems

USGS Publications Warehouse

Palguta, Jennifer; Williams, Colin F.; Ingebritsen, Steven E.; Hickman, Stephen H.; Sonnenthal, Eric

2011-01-01

Interactions between hydrothermal fluids and rock alter mineralogy, leading to the formation of secondary minerals and potentially significant physical and chemical property changes. Reactive transport simulations are essential for evaluating the coupled processes controlling the geochemical, thermal and hydrological evolution of geothermal systems. The objective of this preliminary investigation is to successfully replicate observations from a series of hydrothermal laboratory experiments [Morrow et al., 2001] using the code TOUGHREACT. The laboratory experiments carried out by Morrow et al. [2001] measure permeability reduction in fractured and intact Westerly granite due to high-temperature fluid flow through core samples. Initial permeability and temperature values used in our simulations reflect these experimental conditions and range from 6.13 × 10−20 to 1.5 × 10−17 m2 and 150 to 300 °C, respectively. The primary mineralogy of the model rock is plagioclase (40 vol.%), K-feldspar (20 vol.%), quartz (30 vol.%), and biotite (10 vol.%). The simulations are constrained by the requirement that permeability, relative mineral abundances, and fluid chemistry agree with experimental observations. In the models, the granite core samples are represented as one-dimensional reaction domains. We find that the mineral abundances, solute concentrations, and permeability evolutions predicted by the models are consistent with those observed in the experiments carried out by Morrow et al. [2001] only if the mineral reactive surface areas decrease with increasing clay mineral abundance. This modeling approach suggests the importance of explicitly incorporating changing mineral surface areas into reactive transport models.

Probing the intrinsically oil-wet surfaces of pores in North Sea chalk at subpore resolution.

PubMed

Hassenkam, T; Skovbjerg, L L; Stipp, S L S

2009-04-14

Pore surface properties control oil recovery. This is especially true for chalk reservoirs, where pores are particularly small. Wettability, the tendency for a surface to cover itself with fluid, is traditionally defined by the angle a droplet makes with a surface, but this macroscopic definition is meaningless when the particles are smaller than even the smallest droplet. Understanding surface wetting, at the pore scale, will provide clues for more effective oil recovery. We used a special mode of atomic force microscopy and a hydrophobic tip to collect matrices of 10,000 force curves over 5- x 5-mum(2) areas on internal pore surfaces and constructed maps of topography, adhesion, and elasticity. We investigated chalk samples from a water-bearing formation in the Danish North Sea oil fields that had never seen oil. Wettability and elasticity were inhomogeneous over scales of 10s of nanometers, smaller than individual chalk particles. Some areas were soft and hydrophobic, whereas others showed no correlation between hardness and adhesion. We conclude that the macroscopic parameter, "wetting," averages the nanoscopic behavior along fluid pathways, and "mixed-wet" samples have patches with vastly different properties. Development of reservoir hydrophobicity has been attributed to infiltrating oil, but these new results prove that wettability and elasticity are inherent properties of chalk. Their variability, even on single particles, must result from material originally present during sedimentation or material sorbed from the pore fluid some time later.