Laboratory simulation of the effects of overburden stress on the specific storage of shallow artesian aquifers

USGS Publications Warehouse

Sepúlveda, Nicasio; Zack, A.L.; Krishna, J.H.; Quinones-Aponte, Vicente; Gomez-Gomez, Fernando; Morris, G.L.

1990-01-01

A laboratory experiment to measure the specific storage of an aquifer material was conducted. A known dead load, simulating an overburden load, was applied to a sample of completely saturated aquifer material contained inside a cylinder. After the dead load was applied, water was withdrawn from the sample, causing the hydrostatic pressure to decrease and the effective stress to increase. The resulting compression of the sample and the amount of water withdrawn were measured after equilibrium was reached. The procedure was repeated by increasing the dead load and the hydrostatic pressure followed by withdrawing water to determine new values of effective stress and compaction. The simulated dead loads are typical of those experienced by shallow artesian aquifers. The void ratio and the effective stress of the aquifer sample, as simulated by different dead loads, determine the pore volume compressibility which, in turn, determines the values of specific storage. An analytical algorithm was used to independently determine the stress dependent profile of specific storage. These values are found to be in close agreement with laboratory results. Implications for shallow artesian aquifers, with relatively small overburden stress, are also addressed.

In-place oil shale resources of the Mahogany zone sorted by grade, overburden thickness and stripping ratio, Green River Formation, Piceance Basin, Colorado and Uinta Basin, Utah

USGS Publications Warehouse

Birdwell, Justin E.; Mercier, Tracey J.; Johnson, Ronald C.; Brownfield, Michael E.

2015-01-01

A range of geological parameters relevant to mining oil shale have been examined for the Mahogany zone of the Green River Formation in the Piceance Basin, Colorado, and Uinta Basin, Utah, using information available in the U.S. Geological Survey Oil Shale Assessment database. Basinwide discrete and cumulative distributions of resource in-place as a function of (1) oil shale grade, (2) Mahogany zone thickness, (3) overburden thickness, and (4) stripping ratio (overburden divided by zone thickness) were determined for both basins on a per-acre basis, and a resource map showing the areal distribution of these properties was generated. Estimates of how much of the Mahogany zone resource meets various combinations of these parameters were also determined. Of the 191.7 billion barrels of Mahogany zone oil in-place in the Piceance Basin, 32.3 percent (61.8 billion barrels) is associated with oil shale yielding at least 25 gallons of oil per ton (GPT) of rock processed, is covered by overburden 1,000 feet thick or less, and has a stripping ratio of less than 10. In the Uinta Basin, 14.0 percent (29.9 billion barrels) of the 214.5 billion barrels of Mahogany zone oil in-place meets the same overburden and stripping ratio criteria but only for the lower grade cutoff of 15 GPT.

Constitutive models for the Etchegoin Sands, Belridge Diatomite, and overburden formations at the Lost Hills oil field, California

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

FOSSUM,ARLO F.; FREDRICH,JOANNE T.

2000-04-01

This report documents the development of constitutive material models for the overburden formations, reservoir formations, and underlying strata at the Lost Hills oil field located about 45 miles northwest of Bakersfield in Kern County, California. Triaxial rock mechanics tests were performed on specimens prepared from cores recovered from the Lost Hills field, and included measurements of axial and radial stresses and strains under different load paths. The tested intervals comprise diatomaceous sands of the Etchegoin Formation and several diatomite types of the Belridge Diatomite Member of the Monterey Formation, including cycles both above and below the diagenetic phase boundary betweenmore » opal-A and opal-CT. The laboratory data are used to drive constitutive parameters for the Extended Sandler-Rubin (ESR) cap model that is implemented in Sandia's structural mechanics finite element code JAS3D. Available data in the literature are also used to derive ESR shear failure parameters for overburden formations. The material models are being used in large-scale three-dimensional geomechanical simulations of the reservoir behavior during primary and secondary recovery.« less

Use of overburden rocks from open-pit coal mines and waste coals of Western Siberia for ceramic brick production with a defect-free structure

NASA Astrophysics Data System (ADS)

Stolboushkin, A. Yu; Ivanov, A. I.; Storozhenko, G. I.; Syromyasov, V. A.; Akst, D. V.

2017-09-01

The rational technology for the production of ceramic bricks with a defect-free structure from coal mining and processing wastes was developed. The results of comparison of physical and mechanical properties and the structure of ceramic bricks manufactured from overburden rocks and waste coal with traditional for semi-dry pressing mass preparation and according to the developed method are given. It was established that a homogeneous, defect-free brick texture obtained from overburden rocks of open-pit mines and waste coal improves the quality of ceramic wall materials produced by the method of compression molding by more than 1.5 times compared to the brick with a traditional mass preparation.

Cosmic-muon intensity measurement and overburden estimation in a building at surface level and in an underground facility using two BC408 scintillation detectors coincidence counting system.

PubMed

Zhang, Weihua; Ungar, Kurt; Liu, Chuanlei; Mailhot, Maverick

2016-10-01

A series of measurements have been recently conducted to determine the cosmic-muon intensities and attenuation factors at various indoor and underground locations for a gamma spectrometer. For this purpose, a digital coincidence spectrometer was developed by using two BC408 plastic scintillation detectors and an XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The results indicate that the overburden in the building at surface level absorbs a large part of cosmic ray protons while attenuating the cosmic-muon intensity by 20-50%. The underground facility has the largest overburden of 39 m water equivalent, where the cosmic-muon intensity is reduced by a factor of 6. The study provides a cosmic-muon intensity measurement and overburden assessment, which are important parameters for analysing the background of an HPGe counting system, or for comparing the background of similar systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modeling an exhumed basin: A method for estimating eroded overburden

USGS Publications Warehouse

Poelchau, H.S.

2001-01-01

The Alberta Deep Basin in western Canada has undergone a large amount of erosion following deep burial in the Eocene. Basin modeling and simulation of burial and temperature history require estimates of maximum overburden for each gridpoint in the basin model. Erosion can be estimated using shale compaction trends. For instance, the widely used Magara method attempts to establish a sonic log gradient for shales and uses the extrapolation to a theoretical uncompacted shale value as a first indication of overcompaction and estimation of the amount of erosion. Because such gradients are difficult to establish in many wells, an extension of this method was devised to help map erosion over a large area. Sonic A; values of one suitable shale formation are calibrated with maximum depth of burial estimates from sonic log extrapolation for several wells. This resulting regression equation then can be used to estimate and map maximum depth of burial or amount of erosion for all wells in which this formation has been logged. The example from the Alberta Deep Basin shows that the magnitude of erosion calculated by this method is conservative and comparable to independent estimates using vitrinite reflectance gradient methods. ?? 2001 International Association for Mathematical Geology.

TEM measurement in a low resistivity overburden performed by using low temperature SQUID

NASA Astrophysics Data System (ADS)

Ji, Yanju; Du, Shangyu; Xie, Lijun; Chang, Kai; Liu, Yang; Zhang, Yi; Xie, Xiaoming; Wang, Yuan; Lin, Jun; Rong, Liangliang

2016-12-01

Exploration of areas with thick low resistivity overburden is still a challenge for time domain transient electromagnetic method (TEM). We report modeling of a sandwich-layered earth by simulating the B field response with different conductive target layer thicknesses, thus obtaining a relationship between the resolution of the B field and the exploration depth. A low temperature Superconducting Quantum Interference Device (SQUID) is an ideal sensor for measuring the secondary magnetic field B in TEM measurements, because its sensitivity of several fT/√Hz is independent of frequency. In our TEM experiments, we utilized two different coils as receivers, a simple SQUID system, and a large transmitter loop of 200 × 200 m2 to compare the detected decay curves. At some measurement points, a decay signal of more than 300 ms duration was obtained by using the SQUID. Apparent resistivity profiles of about 9 km length are presented.

Forced folding and complex overburden deformation associated with magmatic intrusion in the Vøring Basin, offshore Norway

NASA Astrophysics Data System (ADS)

Omosanya, Kamaldeen Olakunle; Johansen, Ståle E.; Eruteya, Ovie Emmanuel; Waldmann, Nicolas

2017-06-01

In this study, three-dimensional seismic reflection and borehole data from the Vøring Basin, offshore Norway have been used to characterize a supra-sill related forced fold to understand its evolution and relevance in the context of regional tectonics. Magmatic sills were recognised to be positive high-amplitude anomalies with similar polarity to the seabed reflection. The seismic dataset reveals two groups of sills in the study area comprising interconnected sills beneath the regional forced fold, and those intruded into the overburden. Magmatic sills forming the interconnected sill complex are emplaced at a depth of about 5.5 s TWTT below the modern seafloor. Aspect ratio (length/width), A for the sills ranges from 1.63-6.90. The regional forced fold is interpreted based on its bathymetric and seismic-stratigraphic expression on horizon H7, which is part of the Palaeocene to Eocene Tang Formation. Amplitude of the accommodation fold is about 780 km2. Hydrothermal vent complexes and fluid-flow conduits in the study area develop above the sill edges and on the flanks of the interconnected sill complex extending from the lower part of the Tang Formation to the uppermost section of the Brygge Formation evidencing vertically focussed fluid flow in the study area. The overlying overburden is in turn deformed and structurally compartmentalized through forced folding and Late Cenozoic tectonics. We demonstrate that accommodation folding is formed in response to the emplacement of several interconnected sills during the opening of the Norwegian-Greenland Seas. Sill emplacement in the study area causes uplift of the Cretaceous to Palaeocene depocentre prior to further restructuration during Cenozoic tectonic inversion. Magmatic intrusions documented in this study have wider implications for understanding supra-sill deformations along volcanic margins with well-developed emplaced sills at depth and likewise hydrocarbon prospectivity in the study area.

Studies on a middle Pennsylvanian compression-impression flora from the overburden of the Herrin (No. 6) coal at Carterville, Illinois

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

Gastaldo, R.A.

1978-01-01

An authigenically cemented flora from the overburden of the Herrin (No. 6) Coal at Carterville, Illinois has yielded a diverse plant assemblage. Twenty-seven genera and fifty-five species are recognized, of which four taxa are described as new. The dominant component is pteridophyte foliage of Pecopteris Brongniart. The floral assemblage is representative of the Middle Pennsylvanian of North America due to an abundance of Upper Allegheny forms, and representative of the Lower Conemaugh (Stephanian). The flora is equated to Zone 10 of Read and Mamay, and the Westphalian D of Europe.

Overburden, Stigma, and Perceived Agency: Teachers as HIV Prevention Educators in Urban Zambia

PubMed Central

Henning, Margaret; Khanna, Sunil K.

2016-01-01

Sub-Saharan Africa is home to more than 70% of the global HIV-positive population. In Zambia, as well as in other parts of Africa, deaths from AIDS and associated infections have created a generation of households headed by children, a situation that negatively affects the chances for economic and health improvements in the region. In contemplating possible public health interventions around HIV prevention, we found that a growing body of research advocates for school-based HIV programs as an effective strategy to stop the spread of the disease. This work is critical because it explores schoolteachers' perspectives on their potential roles as HIV prevention educators. Semi-structured interviews (n = 12) were conducted among schoolteachers in the Lusaka province of Zambia to collect qualitative data. Analysis of qualitative data revealed three broad and interconnected themes related to the roles and concerns of the participating teachers: 1) the role of overburden; 2) fear of stigma; and 3) perceived lack of agency. These themes are further discussed in the context of the results that focused on the teachers and the adoption of HIV education. Little is known about teachers' perceptions of themselves as HIV educators. Our study suggests that understanding teachers' perceptions and the contextual factors is crucial to the adoption of school-based HIV programs. PMID:29546161

Effect of dissimilatory Fe(III) reducers on bio-reduction and nickel-cobalt recovery from Sukinda chromite-overburden.

PubMed

Esther, Jacintha; Panda, Sandeep; Behera, Sunil K; Sukla, Lala B; Pradhan, Nilotpala; Mishra, Barada K

2013-10-01

The effect of an adapted dissimilatory iron reducing bacterial consortium (DIRB) towards bio-reduction of Sukinda chromite overburden (COB) with enhanced recovery of nickel and cobalt is being reported for the first time. The remarkable ability of DIRB to utilize Fe(III) as terminal electron acceptor reducing it to Fe(II) proved beneficial for treatment of COB as compared to previous reports for nickel leaching. XRD studies showed goethite as the major iron-bearing phase in COB. Under facultative anaerobic conditions, goethite was reduced to hematite and magnetite with the exposure of nickel oxide. FESEM studies showed DIRB to be associated with COB through biofilm formation with secondary mineral precipitates of magnetite deposited as tiny globular clusters on the extra polymeric substances. The morphological and mineralogical changes in COB, post DIRB application, yielded a maximum of 68.5% nickel and 80.98% cobalt in 10 days using 8M H2SO4. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Deformation of Overburden Soil and Interaction with Pile Foundations of Bridges Induced by Normal Faulting

NASA Astrophysics Data System (ADS)

Wu, Liang-Chun; Li, Chien-Hung; Chan, Pei-Chen; Lin, Ming-Lang

2017-04-01

According to the investigations of well-known disastrous earthquakes in recent years, ground deformation induced by faulting is one of the causes for engineering structure damages in addition to strong ground motion. Most of structures located on faulting zone has been destroyed by fault offset. Take the Norcia Earthquake in Italy (2016, Mw=6.2) as an example, the highway bridge in Arquata crossing the rupture area of the active normal fault suffered a quantity of displacement which causing abutment settlement, the piers of bridge fractured and so on. However, The Seismic Design Provisions and Commentary for Highway Bridges in Taiwan, the stating of it in the general rule of first chapter, the design in bridges crossing active fault: "This specification is not applicable of making design in bridges crossing or near active fault, that design ought to the other particular considerations ".This indicates that the safty of bridges crossing active fault are not only consider the seismic performance, the most ground deformation should be attended. In this research, to understand the failure mechanism and the deformation characteristics, we will organize the case which the bridges subjected faulting at home and abroad. The processes of research are through physical sandbox experiment and numerical simulation by discrete element models (PFC3-D). The normal fault case in Taiwan is Shanchiao Fault. As above, the research can explore the deformation in overburden soil and the influences in the foundations of bridges by normal faulting. While we can understand the behavior of foundations, we will make the bridge superstructures into two separations, simple beam and continuous beam and make a further research on the main control variables in bridges by faulting. Through the above mentioned, we can then give appropriate suggestions about planning considerations and design approaches. This research presents results from sandbox experiment and 3-D numerical analysis to simulate

Eco-restoration of a high-sulphur coal mine overburden dumping site in northeast India: A case study

NASA Astrophysics Data System (ADS)

Dowarah, J.; Deka Boruah, H. P.; Gogoi, J.; Pathak, N.; Saikia, N.; Handique, A. K.

2009-10-01

Eco-restoration of mine overburden (OB) or abandoned mine sites is a major environmental concern. In the present investigation, an integrated approach was used to rejuvenate a high-sulphur mine OB dumping site in the Tirap Collieries, Assam, India, which is situated in the Indo-Burma mega-biodiversity hotspot. A mine OB is devoid of true soil character with poor macro and micronutrient content and contains elevated concentrations of trace and heavy metals. Planting of herbs, shrubs, cover crops and tree species at close proximity leads to primary and secondary sere state succession within a period of 3 to 5 years. A variety of plant species were screened for potential use in restoration: herbs, including Sccharum spontaneum, Cymbopogon winterianus Jowitt (citronella), and Cymbopogon flexuosus (lemon grass) cover plants, including Mimosa strigillosa, M. striata, and M. pigra; shrubs, including Sesbania rostrata (dhaincha) and Cassia streata (cassia); and tree species, including Gmelina arborea (gomari) and Dalbergia sissoo (sissoo). Amendment with unmined soil and bio-organic matter was required for primary establishment of some plant species. Management of these plant species at the site will ensure long term sustainable eco-restoration of the coal mine-degraded land.

Fluid flow and assessment of the leakage potential in the Snohvit reservoir and overburden in the Barents Sea

NASA Astrophysics Data System (ADS)

Tasianas, A.

2012-12-01

Department of Geology, University of Tromsø, Dramsveien 201, 9037 Tromsø, Norway Abstract ____________________________________________________________________________ The Snøhvit reservoir and overburden have been an important location for testing Carbon Capture and Storage (CCS) techniques. Fluid flow in the region is caused mainly by repeated glacial cycles and differential geographic uplift, which caused tilting and spilling of various structural traps in the area. Geological modeling, undertaken as part of the ECO2 project activities, has allowed to model the local stratigraphy and any potential fluid flow pathways in order to determine how effective CCS would be in the area. 3D seismic data related to cube ST0306 from the Hammerfest Sedimentary Basin (HFB), covering the Snohvit and Albatross fields, were used to better understand the pathways and mechanisms related to fluid flow in the area and thus propose also potential leakage scenarios. The inclusion of geological features such as gas chimneys, faults, wells, pockmarks at the seabed and vertical fluid flow structures underlying the pockmarks in the models has also allowed to accurately simulate fluid flow through realistic geological models. Leaking of CO2 from the Tubåen Formation (Fm) can partially migrate upwards to the Hekkingen Fm or less deep formations via the faults. If leaking reaches the tertiary faults, CO2 can migrate through the Top kvitting Fm and maybe continue via pipe structures, faults or the clinoforms of the Torsk Fm and accumulate under the Upper Regional Unconformity (URU). The presence of pockmarks at the seabed could indicate further leakage between the URU and the seabed via vertical fluid flow structures underlying the pockmarks. Depending on the leakage mode, models of different types of domain size and grid resolution were created and populated with properties such as porosity (SPhi), vertical permeability (kv), horizontal permeability (Kh), anisotropy ratio (AnIso), Total

Overburdened, Overwhelmed.

ERIC Educational Resources Information Center

Hardy, Lawrence

2003-01-01

Health professionals concerned about children's mental health say schools have become more stressful places and that many students cannot handle the pressure. Factors contributing to students' stress include high-stakes testing, fear of failure, parent pressure, and large impersonal schools. To combat the effects of a large school, Venice High…

Rough wave-like heaped overburden promotes establishment of woody vegetation while leveling promotes grasses during unassisted post mining site development.

PubMed

Frouz, Jan; Mudrák, Ondřej; Reitschmiedová, Erika; Walmsley, Alena; Vachová, Pavla; Šimáčková, Hana; Albrechtová, Jana; Moradi, Jabbar; Kučera, Jiří

2018-01-01

Geodiversity plays an important role in species establishment during spontaneous succession. At post-mining sites in the Czech Republic in 2003, we established plots in which the surface of the heaped overburden was either kept wave-like or leveled. Based on surveys conducted from 2006 to 2015, leveled plots were increasingly dominated by grasses and herbs (and especially by the grass Calamagrostis epigejos) while the wave-like plots were increasingly dominated by the trees Salix caprea and Betula pendula. In 2015, a detailed survey was conducted of the dominant species. Both S. caprea and B. pendula occurred more often in wave-like plots than in leveled plots; this was particularly true for trees taller than 1 m, which were absent in leveled plots. In wave-like plots, leaf and root biomasses of both woody species were higher on the wave slopes than on the wave depressions. Nitrogen content was higher but content stress indicating proline in leaves of S. caprea was lower in wave-like plots than in leveled plots. In wave-like plots, both woody species occurred mainly on wave slopes but C. epigejos occurred mainly in the depressions. We speculate that trees were more abundant in wave-like plots than in leveled plots because the waves trapped tree seeds and snow and because the soil porosity was greater in wave-like than in leveled plots. Grasses may have preferred the leveled plots because soil porosity was lower and clay content was higher in leveled than in wave-like plots. Copyright © 2017 Elsevier Ltd. All rights reserved.

Differential distribution of metals in tree tissues growing on reclaimed coal mine overburden dumps, Jharia coal field (India).

PubMed

Rana, Vivek; Maiti, Subodh Kumar

2018-04-01

Opencast bituminous coal mining invariably generates huge amount of metal-polluted waste rocks (stored as overburden (OB) dumps) and reclaimed by planting fast growing hardy tree species which accumulate metals in their tissues. In the present study, reclaimed OB dumps located in Jharia coal field (Jharkhand, India) were selected to assess the accumulation of selected metals (Pb, Zn, Mn, Cu and Co) in tissues (leaf, stem bark, stem wood, root bark and root wood) of two commonly planted tree species (Acacia auriculiformis A.Cunn. ex Benth. and Melia azedarach L.). In reclaimed mine soil (RMS), the concentrations of pseudo-total and available metals (DTPA-extractable) were found 182-498 and 196-1877% higher, respectively, than control soil (CS). The positive Spearman's correlation coefficients between pseudo-total concentration of Pb and Cu (r = 0.717; p < 0.05), Pb and Co (r = 0.650; p < 0.05), Zn and Mn (0.359), Cu and Co (r = 0.896; p < 0.01) suggested similar sources for Pb-Cu-Co and Mn-Zn. Among the five tree tissues considered, Pb selectively accumulated in root bark, stem bark and leaves; Zn and Mn in leaves; and Cu in root wood and stem wood. These results suggested metal accumulation to be "tissue-specific". The biological indices (BCF, TF leaf , TF stem bark and TF stem wood ) indicated variation in metal uptake potential of different tree tissues. The study indicated that A. auriculiformis could be employed for Mn phytoextraction (BCF, TF leaf , TF stem bark and TF stem wood  > 1). The applicability of both the trees in Cu phytostabilization (BCF > 1; TF leaf , TF stem bark and TF stem wood  < 1) was suggested. The study enhanced knowledge about the selection of tree species for the phytoremediation of coal mine OB dumps and specific tree tissues for monitoring metal pollution.

Inference of strata separation and gas emission paths in longwall overburden using continuous wavelet transform of well logs and geostatistical simulation

NASA Astrophysics Data System (ADS)

Karacan, C. Özgen; Olea, Ricardo A.

2014-06-01

Prediction of potential methane emission pathways from various sources into active mine workings or sealed gobs from longwall overburden is important for controlling methane and for improving mining safety. The aim of this paper is to infer strata separation intervals and thus gas emission pathways from standard well log data. The proposed technique was applied to well logs acquired through the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama, using well logs from a series of boreholes aligned along a nearly linear profile. For this purpose, continuous wavelet transform (CWT) of digitized gamma well logs was performed by using Mexican hat and Morlet, as the mother wavelets, to identify potential discontinuities in the signal. Pointwise Hölder exponents (PHE) of gamma logs were also computed using the generalized quadratic variations (GQV) method to identify the location and strength of singularities of well log signals as a complementary analysis. PHEs and wavelet coefficients were analyzed to find the locations of singularities along the logs. Using the well logs in this study, locations of predicted singularities were used as indicators in single normal equation simulation (SNESIM) to generate equi-probable realizations of potential strata separation intervals. Horizontal and vertical variograms of realizations were then analyzed and compared with those of indicator data and training image (TI) data using the Kruskal-Wallis test. A sum of squared differences was employed to select the most probable realization representing the locations of potential strata separations and methane flow paths. Results indicated that singularities located in well log signals reliably correlated with strata transitions or discontinuities within the strata. Geostatistical simulation of these discontinuities provided information about the location and extents of the continuous channels that may form during mining. If there is a gas

Diffusive leakage of brine from aquifers during CO2 geological storage

NASA Astrophysics Data System (ADS)

Dejam, Morteza; Hassanzadeh, Hassan

2018-01-01

The area of investigation in this study is designed around an improved understanding of fundamentals of the diffusive leakage of brine from a storage aquifer into overlying and underlying low permeability layers during geosequestration of carbon dioxide (CO2) through development of a theoretical model. Here, we consider a two-dimensional domain in cylindrical coordinates, comprised of an aquifer and an overburden, where the interaction between the two media is handled by imposing the continuities of pressures and fluid fluxes at the aquifer-overburden interface. This coupled problem is solved by successive implementation of the Laplace and finite Hankel transforms. The developed solutions can be used to analyze diffusive leakage of brine from the aquifer into overburden and generate type curves for average pressures in the aquifer and overburden during injection and post injection periods. The results show that the leakage rate at early times is scaled with t1/2 while it remains constant at late times. It is also shown that the average pressure in the aquifer is scaled with t for short and long times. Moreover, the average pressure in the overburden is scaled with t at late times while it is scaled with t3/2 at early times. In addition, the results reveal that factors affecting diffusive leakage rate through intact overburden during CO2 storage are, in decreasing order of significance, thickness of overburden, thickness of aquifer, aquifer to overburden permeability ratio, and aquifer to overburden porosity ratio. However, thickness of aquifer has minimal effect on diffusive leakage of brine within post injection period. To evaluate the theoretical model, case studies for two potential sites in United Kingdom, one in Lincolnshire and the other one in the Firth of Forth, are conducted. The field studies show that the diffusive leakage from the aquifer into the overburden diminishes ∼40 years after the injection has ceased for Lincolnshire while it stops after �

Enzyme leaching of surficial geochemical samples for detecting hydromorphic trace-element anomalies associated with precious-metal mineralized bedrock buried beneath glacial overburden in northern Minnesota

USGS Publications Warehouse

Clark, Robert J.; Meier, A.L.; Riddle, G.; ,

1990-01-01

One objective of the International Falls and Roseau, Minnesota, CUSMAP projects was to develop a means of conducting regional-scale geochemical surveys in areas where bedrock is buried beneath complex glacially derived overburden. Partial analysis of B-horizon soils offered hope for detecting subtle hydromorphic trace-element dispersion patterns. An enzyme-based partial leach selectively removes metals from oxide coatings on the surfaces of soil materials without attacking their matrix. Most trace-element concentrations in the resulting solutions are in the part-per-trillion to low part-per-billion range, necessitating determinations by inductively coupled plasma/mass spectrometry. The resulting data show greater contrasts for many trace elements than with other techniques tested. Spatially, many trace metal anomalies are locally discontinuous, but anomalous trends within larger areas are apparent. In many instances, the source for an anomaly seems to be either basal till or bedrock. Ground water flow is probably the most important mechanism for transporting metals toward the surface, although ionic diffusion, electrochemical gradients, and capillary action may play a role in anomaly dispersal. Sample sites near the Rainy Lake-Seine River fault zone, a regional shear zone, often have anomalous concentrations of a variety of metals, commonly including Zn and/or one or more metals which substitute for Zn in sphalerite (Cd, Ge, Ga, and Sn). Shifts in background concentrations of Bi, Sb, and As show a trend across the area indicating a possible regional zoning of lode-Au mineralization. Soil anomalies of Ag, Co, and Tl parallel basement structures, suggesting areas that may have potential for Cobalt/Thunder Baytype silver viens. An area around Baudette, Minnesota, which is underlain by quartz-chlorite-carbonate-altered shear zones, is anomalous in Ag, As, Bi, Co, Mo, Te, Tl, and W. Anomalies of Ag, As, Bi, Te, and W tend to follow the fault zones, suggesting potential

Biodegradation potential of chlorinated solvents in ground water at the Naval Surface Warfare Center, Louisville, Kentucky, July 1999 to February 2000

USGS Publications Warehouse

Vroblesky, Don A.; Bradley, Paul M.; Petkewich, Matthew D.; Casey, Clifton C.

2001-01-01

The U.S. Geological Survey, in cooperation with the U.S. Department of the Navy, Southern Division Naval Facilities Engineering Command, investigated the potential for biodegradation of chlorinated solvents in ground water at the Naval Surface Warfare Center (also known as the Naval Ordnance Station, or the station), Louisville, Kentucky. The subsurface down to at least 100 feet at the station is characterized, from shallowest to deepest, by overburden deposits, a shale layer, and limestone. In general, all of the strata are poorly permeable. The permeable zones of the overburden and the limestone make up the overburden aquifer and the bedrock aquifer, respectively. Observed concentrations of redox-sensitive solutes suggest that the predominant anaerobic terminal electron accepting process in the overburden aquifer can shift between iron reduction and sulfate reduction, possibly as a result of rainfall-induced oxidation events. Daughter-product concentrations and laboratory experiments indicate that a variety of mechanisms, including reductive dechlorination and cometabolic oxidation, appear to be actively

Vulnerability of caregivers of the elderly with dementia: a cross-sectional descriptive study.

PubMed

Leite, Bruna Silva; Camacho, Alessandra Conceição Leite Funchal; Joaquim, Fabiana Lopes; Gurgel, Jonas Lírio; Lima, Thiago Rodrigues; Queiroz, Raquel Santos de

2017-01-01

to evaluate the sociodemographic and clinical profile of the caregivers and its relation with the overburden from the care of the elderly with dementia. a cross-sectional descriptive study; the sample was non-probabilistic, developed with caregivers of elderly people with dementia. The field of investigation was the Health Care Center of the Elderly and their Caregivers (CASIC), in the city of Niterói, Rio de Janeiro, Brazil. Data collection took place from February to June 2016, with the following instruments: a sociodemographic questionnaire and Zarit scale. fifty percent of the caregivers presented moderate overburden; 38% presented little overburden; and 12% moderate/severe overburden. It was observed that the median of weekly care hours increases as the overburden increases. Caregivers with moderate to severe overburden, in the majority, do not share care. it is clear that the overburden of care places the caregiver in conditions of biological and psychological vulnerability. avaliar o perfil sociodemográfico e clínico dos cuidadores e sua relação com a sobrecarga proveniente do cuidado ao idoso com demência. estudo descritivo transversal, a amostra foi do tipo não probabilística, desenvolvida com os cuidadores de idosos com demência. O campo de investigação foi o Centro de Atenção à Saúde do Idoso e seus Cuidadores (CASIC), Niterói, Rio de Janeiro, Brasil. A coleta de dados ocorreu de fevereiro a junho de 2016, com os seguintes instrumentos: questionário sociodemográfico e escala de Zarit. 50% dos cuidadores apresentaram sobrecarga moderada, 38% apresentaram pouca sobrecarga e 12%, sobrecarga moderada/severa. Observou-se que a mediana das horas de cuidados semanais aumenta conforme a sobrecarga aumenta. Cuidadores com sobrecarga de moderada a severa, em caráter majoritário, não dividem o cuidado. Dessa forma, fica claro que a sobrecarga do cuidado coloca o cuidador em condições de vulnerabilidade biológica e psicológica.

A field experiment on Rn flux from reclaimed uranium mill tailings.

PubMed

Hinton, T G; Whicker, F W

1985-04-01

Design and construction techniques are described for a 1.6 ha experimental reclamation plot consisting of a 1-m-thick slab of uranium mill tailings covered with various depths of overburden. A passive, activated charcoal device was developed and used for measurements of Rn flux at the soil surface. Observations on Rn flux vs overburden depth indicated that tailings covered with 1.5 m of revegetated or 0.3 m of bare overburden had Rn exhalation rates comparable to background. Vegetated subplots exhibited a significantly higher (often an order of magnitude) flux than the bare subplots. A positive correlation was observed between precipitation quantities and Rn flux.

Expenditure and Revenue Problems in Central-City School Districts: Problems for the 1980s.

ERIC Educational Resources Information Center

Murphy, Joseph F.; Hack, Walter G.

1983-01-01

Investigates the combination of expenditure and revenue problems facing central-city school districts. Examines educational overburden, related overburden, and cost differentials between central city and other types of districts. Also looks at tax capacity and efforts, and analyzes the effects of Federal and State activity on the problems of city…

Evaluation of engineering properties for the use of leached brown coal ash in soil covers.

PubMed

Mudd, Gavin M; Chakrabarti, Srijib; Kodikara, Jayantha

2007-01-31

The need to engineer cover systems for the successful rehabilitation or remediation of a wide variety of solid wastes is increasing. Some common applications include landfills, hazardous waste repositories, or mine tailings dams and waste rock/overburden dumps. The brown coal industry of the Latrobe Valley region of Victoria, Australia, produces significant quantities of coal ash and overburden annually. There are some site-specific acid mine drainage (AMD) issues associated with overburden material. This needs to be addressed both during the operational phase of a project and during rehabilitation. An innovative approach was taken to investigate the potential to use leached brown coal ash in engineered soil covers on this overburden dump. The basis for this is two-fold: first, the ash has favourable physical characteristics for use in cover systems (such as high storage capacity/porosity, moderately low permeability, and an ability to act as a capillary break layer generating minimal leachate or seepage); and second, the leachate from the ash is mildly alkaline (which can help to mitigate and reduce the risk of AMD). This paper will review the engineering issues involved in using leached brown coal ash in designing soil covers for potentially acid-forming overburden dumps. It presents the results of laboratory work investigating the technical feasibility of using leached brown coal ash in engineered solid waste cover systems.

Overpressure, Low Effective Stress, and Slope Failure in the Ursa Region, Deep-Water Gulf of Mexico

NASA Astrophysics Data System (ADS)

Sawyer, D. E.; Flemings, P. B.

2004-12-01

Slope failures are associated with overpressured pore fluids and low effective stresses in the Quaternary strata of the Ursa Region, deep-water Gulf of Mexico. At Ursa, a permeable turbidite sandstone (the Blue Unit) is overlain by a low-permeability mudstone. Overpressure in the mudstone, measured with a pore pressure penetrometer (piezoprobe), begin within a few meters of the seafloor and extend 250-450 meters down to the Blue Unit. The overpressure ratio (λ *=(Pp-Phydrostatic)\\ (Sv-Phydrostatic), where Sv is the overburden stress, Pp is pore pressure, and Phydrostatic is the hydrostatic pressure) ranges from 0.8 where the overburden is thin to 0.4 where the overburden is thick. Detachment surfaces, mapped with high resolution 3D seismic data, are associated with zones where effective stresses are low. Four subsurface slumps were mapped and are oriented generally northwest-southeast. Slump surface areas are less than 250 km2 and maximum scarp-wall height on the largest slide is ˜120 meters. We interpret that asymmetric loading of the Blue Unit by low-permeable mudstone has driven fluids to where overburden is thin, decreased effective stress, and generated slope instability.

A multimethod Global Sensitivity Analysis to aid the calibration of geomechanical models via time-lapse seismic data

NASA Astrophysics Data System (ADS)

Price, D. C.; Angus, D. A.; Garcia, A.; Fisher, Q. J.; Parsons, S.; Kato, J.

2018-03-01

Time-lapse seismic attributes are used extensively in the history matching of production simulator models. However, although proven to contain information regarding production induced stress change, it is typically only loosely (i.e. qualitatively) used to calibrate geomechanical models. In this study we conduct a multimethod Global Sensitivity Analysis (GSA) to assess the feasibility and aid the quantitative calibration of geomechanical models via near-offset time-lapse seismic data. Specifically, the calibration of mechanical properties of the overburden. Via the GSA, we analyse the near-offset overburden seismic traveltimes from over 4000 perturbations of a Finite Element (FE) geomechanical model of a typical High Pressure High Temperature (HPHT) reservoir in the North Sea. We find that, out of an initially large set of material properties, the near-offset overburden traveltimes are primarily affected by Young's modulus and the effective stress (i.e. Biot) coefficient. The unexpected significance of the Biot coefficient highlights the importance of modelling fluid flow and pore pressure outside of the reservoir. The FE model is complex and highly nonlinear. Multiple combinations of model parameters can yield equally possible model realizations. Consequently, numerical calibration via a large number of random model perturbations is unfeasible. However, the significant differences in traveltime results suggest that more sophisticated calibration methods could potentially be feasible for finding numerous suitable solutions. The results of the time-varying GSA demonstrate how acquiring multiple vintages of time-lapse seismic data can be advantageous. However, they also suggest that significant overburden near-offset seismic time-shifts, useful for model calibration, may take up to 3 yrs after the start of production to manifest. Due to the nonlinearity of the model behaviour, similar uncertainty in the reservoir mechanical properties appears to influence overburden

Limitations of correlation-based redatuming methods

NASA Astrophysics Data System (ADS)

Barrera P, D. F.; Schleicher, J.; van der Neut, J.

2017-12-01

Redatuming aims to correct seismic data for the consequences of an acquisition far from the target. That includes the effects of an irregular acquisition surface and of complex geological structures in the overburden such as strong lateral heterogeneities or layers with low or very high velocity. Interferometric techniques can be used to relocate sources to positions where only receivers are available and have been used to move acquisition geometries to the ocean bottom or transform data between surface-seismic and vertical seismic profiles. Even if no receivers are available at the new datum, the acquisition system can be relocated to any datum in the subsurface to which the propagation of waves can be modeled with sufficient accuracy. By correlating the modeled wavefield with seismic surface data, one can carry the seismic acquisition geometry from the surface closer to geologic horizons of interest. Specifically, we show the derivation and approximation of the one-sided seismic interferometry equation for surface-data redatuming, conveniently using Green’s theorem for the Helmholtz equation with density variation. Our numerical examples demonstrate that correlation-based single-boundary redatuming works perfectly in a homogeneous overburden. If the overburden is inhomogeneous, primary reflections from deeper interfaces are still repositioned with satisfactory accuracy. However, in this case artifacts are generated as a consequence of incorrectly redatumed overburden multiples. These artifacts get even worse if the complete wavefield is used instead of the direct wavefield. Therefore, we conclude that correlation-based interferometric redatuming of surface-seismic data should always be applied using direct waves only, which can be approximated with sufficient quality if a smooth velocity model for the overburden is available.

HVSR Response Evolution due to Seasonal Variation: Observations from 2 Years of Continuous Monitoring

NASA Astrophysics Data System (ADS)

Nurse, K. B.; Milkereit, B.

2017-12-01

The seismic Horizontal to Vertical Spectral Ratio analysis technique reliably gives overburden depth to bedrock, for an independently determined Vs, based on the frequency of the main resonance peak. Above this, smaller resonances reflect the velocity structure within the overburden itself. This range in the HVSR response shows sufficient sensitivity to be exploited as a monitoring tool, to detect change in seismic physical properties and from that, change in overburden conditions. To explore the variation of the response, several 3C geophones have been deployed in southern Ontario, Canada since December 2015 (and ongoing). The local geology is a sedimentary basin with 30m of overburden, a simple 2D environment well suited for the HVSR method. Data are collected for 15s per minute, with an effective frequency band of 2-400Hz. HVSR estimates are produced for each sampling period and archived. Over these two years, winter freeze/thaw, saturated spring and summer draught conditions were sampled. H/V daily averages are dominated by the stable 3Hz resonance due to the overall surface layer, but smaller spectral peaks up to 100Hz are clear and evolve in frequency and amplitude over the collection period. Ground freeze/thaw cycles are clearly evident by significant reduction in the horizontal field, but also the changing of the soil moisture content throughout the year causes subtle shifts in the response (correlated to rain events and water table variation). The long term sampling does show a sensitivity of the HVSR method to the overburden in proximity to the sensor, and suggests a possibility for its use in monitoring soil / water-table conditions. But it also highlights that the estimate from an isolated H/V acquisition does include this variability and needs to be adequately quantified in VS30 estimates.

Salt diapirs in the Dead Sea basin and their relationship to Quaternary extensional tectonics

USGS Publications Warehouse

Al-Zoubi, A.; ten Brink, Uri S.

2001-01-01

Regional extension of a brittle overburden and underlying salt causes differential loading that is thought to initiate the rise of reactive diapirs below and through regions of thin overburden. We present a modern example of a large salt diapir in the Dead Sea pull-apart basin, the Lisan diapir, which we believe was formed during the Quaternary due to basin transtension and subsidence. Using newly released seismic data that are correlated to several deep wells, we determine the size of the diapir to be 13 x 10 km. its maximum depth 7.2 km. and its roof 125 m below the surface. From seismic stratigraphy, we infer that the diapir started rising during the early to middle Pleistocene as this section of the basin underwater rapid subsidence and significant extension of the overburden. During the middle to late Pleistocene, the diapir pierced through the extensionally thinned overburden, as indicated by rim synclines, which attest to rapid salt withdrawal from the surrounding regions. Slight positive topography above the diapir and shallow folded horizons indicate that it is still rising intermittently. The smaller Sedom diapir, exposed along the western bounding fault of the basin is presently rising and forms a 200 m-high ridge. Its initiation is explained by localized E-W extension due monoclinal draping over the edge of a rapidly subsiding basin during the early to middle Pleistocene, and its continued rise by lateral squeezing due to continued rotation of the Amazyahu diagonal fault. 

The Detection And Analysis Of Blasting Problems Encountered In A Colliery Using High Speed Photography

NASA Astrophysics Data System (ADS)

Rorke, A. J.; Kohler, E. W.

1987-09-01

Premature initiation of ANFO (an explosive mixture of Ammonium Nitrate and Fuel Oil) at a large colliery, near Witbank, was first detected from routine high speed films taken of large mid-burden, and overburden blasts. The analysis of these films shows that the rapid migration of very hot gasses through cracks ahead of the blast may have caused the explosive to initiate prematurely. The problem was not seen in the less competent overburden rocks. A less sensitive explosive has been successfully tried. The assessment of these blasts using high speed photography is discussed.

Geology and preliminary hydrogeologic characterization of the cell-house site, Berlin, New Hampshire, 2003-04

USGS Publications Warehouse

Degnan, James R.; Clark, Stewart F.; Harte, Philip T.; Mack, Thomas J.

2005-01-01

At the cell-house site, thin, generally less than 20-foot thick overburden, consisting of till and demolition materials, overlies fractured crystalline bedrock. Bedrock at the site consists of gneiss with thin discontinuous lenses of chlorite schist and discontinuous tabular pegmatite. Two distinct fracture domains, with principal trends to the west and northwest, and to the north, overlap near the site. The cell-house site shows principal trends common to both domains. Gneiss is the most abundant rock at the site. Steeply dipping fractures within the gneiss terminate on subhorizontal contacts with pegmatite and on moderately dipping contacts with chlorite schist. Steeply northwest-dipping en Echelon fracture zones, parallel joint zones, and silicified brittle faults show consistent strikes to the northeast. Gently east-dipping to subhorizontal fractures, sub-parallel to gneissosity, strike northeast. The impermeable cap, barrier wall, and bedrock surface topography affect ground-water flow in the overburden. There is relatively little ground-water flow in the overburden in the capped area and a poor hydraulic connection between the overburden and the underlying bedrock over most of the site. The overburden beneath the cap may receive inflow through or beneath the barrier wall, or by flow through vertical fractures in the underlying bedrock beneath the barrier wall. The bedrock aquifer near the river is well connected to the river and head difference in the bedrock across the site are large (greater than 13 ft). Horizontal hydraulic conductivities of 0.2 to 20 ft/d were estimated for the bedrock. Individual fractures or fracture zones likely have hydraulic conductivities greater than the bulk rock. Subhorizontal fractures occur at pegmatite contacts or along chlorite schist lenses and may serve as ground-water conduits to the steeply dipping fractures in gneiss. The effective hydraulic conductivity across the site is likely to be in the low range of the estimated

Effectiveness of the addition of alkaline materials at surface coal mines in preventing or abating acid mine drainage--Part 2. Mine site case studies

USGS Publications Warehouse

Brady, Keith; Smith, Michael W.; Beam, Richard L.; Cravotta,, Charles A.

1990-01-01

The effectiveness of preventing or ameliorating acid mine drainage (AMD) through the application of alkaline additives is evaluated for eight surface coal mines in Pennsylvania. Many of the mine sites had overburden characteristics that made prediction of post‐mining water quality uncertain. Alkaline materials were applied at rates ranging from 42 to greater than 1,000 tons as calcium carbonate per acre. In addition, two sites that were mined and reclaimed without alkaline additives are included for comparative purposes. Overburden sulfur concentration and "neutralization potential" (NP) data for multiple strata at each mine site were used to compute the cumulative, mass‐weighted "maximum potential acidity" (MPA) and "net neutralization potential" (NNP = NP ‐ MPA) by using three different calculation methods. Post‐reclamation water‐quality data were used to compute the net alkalinity (= alkalinity ‐ acidity). The most conservative determination of NNP, whereby MPA is calculated by multiplying the total sulfur concentration, in weight percent, by 62.5 instead of 31.25, yielded the best agreement with net alkalinity (patching signs on NNP and net alkalinity). The error in prediction using each method was that the reclaimed overburden was computed to be alkaline overall (NNP > 0), but the post‐reclamation water was acid (net alkalinity < 0). In general, alkaline addition rates were probably insufficient to neutralize, or too late to prevent, acid production in the mine spoil. At six of the seven mine sites that had overburden with insufficient NP relative to MPA (NNP < 0), the addition of alkaline materials failed to create alkaline mine drainage; AMD was formed or persisted. A control site which also had insufficient alkaline material, but did not incorporate alkaline additives, generated severe AMD. Two sites that had substantial, natural alkaline overburden produced alkaline drainage. Although the addition rates appear to be inadequate, other factors

Downhole seismic monitoring with Virtual Sources

NASA Astrophysics Data System (ADS)

Bakulin, A.; Calvert, R.

2005-12-01

Huge quantities of remaining oil and gas reserves are located in very challenging geological environments covered by salt, basalt or other complex overburdens. Conventional surface seismology struggles to deliver images necessary to economically explore them. Even if those reserves are found by drilling successful production critically depends on our ability to ``see" in real time where fluids are drawn from and how pressure changes throughout the reservoirs. For relatively simple overburdens surface time-lapse (4D) seismic monitoring became industry choice for aerial reservoir surveillance. For complex overburdens, 4D seismic does not have enough resolution and repeatability to answer the questions of reservoir engineers. For instance, often reservoir changes are too small to be detected from surface or these changes occur in such pace that all wells will be placed before we can detect them which greatly reduces the economical impact. Two additional challenges are present in real life that further complicate active monitoring: first, near-surface condition do change between the surveys (water level movement, freezing/thawing, tide variations etc) and second, repeating exact same acquisition geometry at the surface is difficult in practice. Both of these things may lead to false 4D response unrelated to reservoir changes. Virtual Source method (VSM) has been recently proposed as a way to eliminate overburden distortions for imaging and monitoring. VSM acknowledges upfront that our data inversion techniques are unable to unravel the details of the complex overburdens to the extent necessary to remove the distortions caused by them. Therefore VSM advocates placing permanent downhole geophones below that most complex overburden while still exciting signals with a surface sources. For instance, first applications include drilling instrumented wells below complicated near-surface, basalt or salt layer. Of course, in an ideal world we would prefer to have both downhole

How crawler track-mounted conveyors improve bulk handling's economics

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

Hawkins, G.P.

1984-11-01

Crawler track-mounted conveyors can be used in most applications formerly requiring stacking, reclaiming or movement from excavators to bench conveyors. The crawler track-mounted conveyor has been automated for push button operation and allows mobilization of in-pit operations for the movement of overburden, minerals and coal. In-pit mobilization of crushers, the use of mobilized steep angle conveyor for the removal of coal from the pit, and the movement of overburden from excavation to spoil can all be done more economically when a combination of a crawler track mounted conveyor is used in conjunction with a shiftable or fixed conveyor.

Effects of coal mine subsidence in the Sheridan, Wyoming, area

USGS Publications Warehouse

Dunrud, C. Richard; Osterwald, Frank W.

1980-01-01

Analyses of the surface effects of past underground coal mining in the Sheridan, Wyoming, area suggest that underground mining of strippable coal deposits may damage the environment more over long periods of time than would modern surface mining, provided proper restoration procedures are followed after surface mining. Subsidence depressions and pits are a continuing hazard to the environment and to man's activities in the Sheridan, Wyo., area above abandoned underground mines in weak overburden less than about 60 m thick and where the overburden is less than about 10-15 times the thickness of coal mined. In addition, fires commonly start by spontaneous ignition when water and air enter the abandoned mine workings via subsidence cracks and pits. The fires can then spread to unmined coal as they create more cavities, more subsidence, and more cracks and pits through which air can circulate. In modern surface mining operations the total land surface underlain by minable coal is removed to expose the coal. The coal is removed, the overburden and topsoil are replaced, and the land is regraded and revegetated. The land, although disturbed, can be more easily restored and put back into use than can land underlain by abandoned underground mine workings in areas where the overburden is less than about 60 m thick or less than about 10-15 times the thickness of coal mined. The resource recovery of modern surface mining commonly is much greater than that of underground mining procedures. Although present-day underground mining technology is advanced as compared to that of 25-80 years ago, subsidence resulting from underground mining of thick coal beds beneath overburden less than about 60 m thick can still cause greater damage to surface drainage, ground water, and vegetation than can properly designed surface mining operations. This report discusses (11 the geology and surface and underground effects of former large-scale underground coal mining in a 50-km 2 area 5-20 km

Numerical models of diapiric structures: comparison of the 2D finite deformation field between Rayleigh-Taylor like and down-built like diapirs

NASA Astrophysics Data System (ADS)

Fuchs, Lukas; Schmeling, Harro; Koyi, Hemin

2013-04-01

Magmatic and salt diapirs are common structures in different tectonic regimes. Salt diapirs can act as possible hydrocarbon traps and, moreover, they could be used as repositories for nuclear waste disposal. Understanding the evolution and the dynamics of diapirs as well as their driving mechanisms has fundamental and applied significance. In general, salt diapirs seem to be driven by differential loading of sediments creating an uneven load that drives the salt from high to low pressure areas, e.g. a down-built diapir. Magmatic diapirs, instead, seem to be driven by buoyancy where lighter material rises vertically through a heavier overburden, i.e. a classical Rayleigh-Taylor instability [RTI]. These different driving mechanisms and dynamics strongly govern the internal deformation of the diapirs. In this study, we use a two-dimensional finite difference code (FDCON) in combination with a marker and cell method to calculate the finite deformation within diapiric structures. Thereby, we distinguish between the two different driving mechanisms, i.e. the differential loading and the buoyancy. We calculate the different finite deformation patterns during the evolution of RTI's and down-built diapirs for different viscosity ratios m = -?buoyant- ?overburden. The deformation pattern in the buoyant layer shows similarities for both diapiric structures, like high shear deformation at the bottom, a high finite deformation within the middle of the stem, and an increasing maximum finite deformation for a decreasing m. However, the strain partitioning between the overburden and the source layer is different within down-built diapirs compared to the RTI's, even for down-built diapirs with m = 1. Thus a higher amount of the total strain induced by down-building is concentrated within the buoyant layer. Moreover, in the case of viscosity ratios of m = 0.1 or 1 the sinking overburden units create an internal rotation within the diapiric bulb. This rotation depends indirectly on

Cosmic muon flux measurements at the Kimballton Underground Research Facility

NASA Astrophysics Data System (ADS)

Kalousis, L. N.; Guarnaccia, E.; Link, J. M.; Mariani, C.; Pelkey, R.

2014-08-01

In this article, the results from a series of muon flux measurements conducted at the Kimballton Underground Research Facility (KURF), Virginia, United States, are presented. The detector employed for these investigations, is made of plastic scintillator bars readout by wavelength shifting fibers and multianode photomultiplier tubes. Data was taken at several locations inside KURF, spanning rock overburden values from ~ 200 to 1450 m.w.e. From the extracted muon rates an empirical formula was devised, that estimates the muon flux inside the mine as a function of the overburden. The results are in good agreement with muon flux calculations based on analytical models and MUSIC.

Acid-base accounting to predict post-mining drainage quality on surface mines.

PubMed

Skousen, J; Simmons, J; McDonald, L M; Ziemkiewicz, P

2002-01-01

Acid-base accounting (ABA) is an analytical procedure that provides values to help assess the acid-producing and acid-neutralizing potential of overburden rocks prior to coal mining and other large-scale excavations. This procedure was developed by West Virginia University scientists during the 1960s. After the passage of laws requiring an assessment of surface mining on water quality, ABA became a preferred method to predict post-mining water quality, and permitting decisions for surface mines are largely based on the values determined by ABA. To predict the post-mining water quality, the amount of acid-producing rock is compared with the amount of acid-neutralizing rock, and a prediction of the water quality at the site (whether acid or alkaline) is obtained. We gathered geologic and geographic data for 56 mined sites in West Virginia, which allowed us to estimate total overburden amounts, and values were determined for maximum potential acidity (MPA), neutralization potential (NP), net neutralization potential (NNP), and NP to MPA ratios for each site based on ABA. These values were correlated to post-mining water quality from springs or seeps on the mined property. Overburden mass was determined by three methods, with the method used by Pennsylvania researchers showing the most accurate results for overburden mass. A poor relationship existed between MPA and post-mining water quality, NP was intermediate, and NNP and the NP to MPA ratio showed the best prediction accuracy. In this study, NNP and the NP to MPA ratio gave identical water quality prediction results. Therefore, with NP to MPA ratios, values were separated into categories: <1 should produce acid drainage, between 1 and 2 can produce either acid or alkaline water conditions, and >2 should produce alkaline water. On our 56 surface mined sites, NP to MPA ratios varied from 0.1 to 31, and six sites (11%) did not fit the expected pattern using this category approach. Two sites with ratios <1 did not

A techno-economic model for optimum regeneration of surface mined land

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Manas K.; Sinha, Indra N.

2006-07-01

The recent global scenario in the mineral sector may be characterized by rising competitiveness, increasing production costs and a slump in market price. This has pushed the mineral sector in general and that in the developing countries in particular to a situation where the industry has a limited capacity to sustain unproductive costs. This, more often than not, results in a situation where the industry fails to ensure environmental safeguards during and after mineral extraction. The situation is conspicuous in the Indian coal mining industry where more than 73% production comes from surface operations. India has an ambitious power augmentation projection for the coming 10 years. A phenomenal increase in coal production is proposed from the power grade coalfields in India. One of the most likely fall-outs of land degradation due to mining in these areas would be significant reduction of agricultural and other important land-uses. Currently, backfilling costs are perceived as prohibitive and abandonment of land is the easy way out. This study attempts to provide mine planners with a mathematical model that distributes generated overburden at defined disposal options while ensuring maximization of backfilled land area at minimum direct and economic costs. Optimization has been accomplished by linear programming (LP) for optimum distribution of each year’s generated overburden. Previous year’s disposal quantity outputs are processed as one set of the inputs to the LP model for generation of current year’s disposal output. From various geo-mining inputs, site constants of the LP constraints are calculated. Arrived value of economic vectors, which guide the programming statement, decides the optimal overburden distribution in defined options. The case example (with model test run) indicates that overburden distribution is significantly sensitive to coal seam gradient. The model has universal applicability to cyclic system (shovel dumper combination) of opencast

Log analysis of six boreholes in conjunction with geologic characterization above and on top of the Weeks Island salt dome

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

Sattler, A.R.

1996-04-01

Six boreholes were drilled during the geologic characterization and diagnostics of the Weeks Island sinkhole that is over the two-tiered salt mine which was converted for oil storage by the US Strategic Petroleum Reserve. These holes were drilled to provide for geologic characterization of the Weeks Island Salt Dome and its overburden in the immediate vicinity of the sinkhole (mainly through logs and core); to establish a crosswell configuration for seismic tomography; to establish locations for hydrocarbon detection and tracer injection; and to Provide direct observations of sinkhole geometry and material properties. Specific objectives of the logging program were to:more » (1) identify the top of and the physical state of the salt dome; (2) identify the water table; (3) obtain a relative salinity profile in the aquifer within the alluvium, which ranges from the water table directly to the top of the Weeks Island salt dome; and (4) identify a reflecting horizon seen on seismic profiles over this salt dome. Natural gamma, neutron, density, sonic, resistivity and caliper logs were run. Neutron and density logs were run from inside the well casing because of the extremely unstable condition of the deltaic alluvium overburden above the salt dome. The logging program provided important information about the salt dome and the overburden in that (1) the top of the salt dome was identified at {approximately}189 ft bgl (103 ft msl), and the top of the dome contains relatively few fractures; (2) the water table is approximately 1 ft msl, (3) this aquifer appears to become steadily more saline with depth; and (4) the water saturation of much of the alluvium over the salt dome is shown to be influenced by the prevalent heavy rainfall. This logging program, a part of the sinkhole diagnostics, provides unique information about this salt dome and the overburden.« less

Seafloor Soil Sampling and Geotechnical Parameter Determination - Handbook

DTIC Science & Technology

1979-08-01

Ko + Au(I- Ko )] (7-1) 97 I where ;v = effective overburden pressure (Section 6.1.3) K 0 = coefficient of lateral earLh pressure AU = reference pore...sin i+(6/a Vcos i su [ Ko i 0 V(7-2) a 1 + (2 A -1) sin 4 Vf 99 to oiU - ~1 where ; = overburden pressure ot depth where strength, Su, is to be...Rickivdo ANtON TfIW)I* SKO 11"will NY tIAltA. JOh I~ 11 Acwtx. CO IIRAI Ir/ IA M6I~. CA IIKOWN. RODEIRT Unoily. At. IIUILOCK 1.3 Ju4 I.AYri3X lt,! WA WM TA IIIf O~mc CA 128

Spatial variations in deformation mechanisms along the Main Central thrust zone: Implications for the evolution of the MCT in the Darjeeling -Sikkim Himalaya

NASA Astrophysics Data System (ADS)

Bhattacharyya, Kathakali; Mitra, Gautam

2014-12-01

In the Darjeeling-Sikkim Himalaya, we recognize two distinct MCT sheets: the structurally higher MCT1 and the lower MCT2. Microstructural studies from three different segments along the transport direction of the MCT2 fault zone suggest that the fault has undergone strain softening by different mechanisms. The geometry of the tapered crystalline orogenic wedge resulted in variation of overburden along the MCT2. Strain softening by different deformation mechanisms accommodated translation of ⩾100 km along a thin MCT2 fault zone. As the mylonitic trailing part of the MCT2 in Pelling had the greatest overburden, deformation took place by dislocation creep in quartz and by microfracturing in feldspar. Reaction softening of feldspar produced an intrinsically weak matrix that primarily controlled the deformation, resulting in a strain softening fault zone. At Soreng MCT2 zone, under intermediate crustal conditions, finer-grained recrystallized quartz and micaceous matrix deformed by grain-size sensitive diffusion creep mechanisms resulting in strain softening. The fault rocks at Sivitar had the least overburden and record a prominent mineralogical change from the protolith; strain softening occurred by pressure solution slip, possibly by a combination of grain-size reduction by cataclasis and an increase in fluid activity.

Natural radioactivity of the tar-sand deposits of Ondo State, Southwestern Nigeria

NASA Astrophysics Data System (ADS)

Fasasi, M. K.; Oyawale, A. A.; Mokobia, C. E.; Tchokossa, P.; Ajayi, T. R.; Balogun, F. A.

2003-06-01

A combination of gamma spectrometry and energy dispersive X-ray fluorescence was used to determine the presence and level of radioactivity of radionuclides in bituminous sand and overburden obtained from bituminous sand deposits in Ondo State Nigeria for the purpose of providing baseline data and assessing its impact on the environment. The radionuclides identified with reliable regularity belong to the decay series of naturally occurring radionuclides headed by 238U and 232Th. The non-decay series of naturally occurring 40K was found to be below the limit of detection. The average specific activity concentration values obtained for 214 Bi, 208Tl, and 226Ra in the overburden are 165.64±2.91, 150.25±2.91 and 60.97±2.27 Bq kg -1, respectively. The measured activity in the bituminous sand layer is so low that it can be said to be non-radioactive. The result of the EDXRF supports the presence of radioelements in the overburden, which are likely to be embedded in accessory minerals like zircon and tourmaline. Thus, surface exploration technique using soil-gas radon measurement will not yield the desired result. Furthermore, the level of radioelements and associated decay daughter 222Rn is not expected to cause any health hazard.

Results of a monitoring program of continuous water levels and physical water properties at the Operable Unit 1 area of the Savage Municipal Well Superfund site, Milford, New Hampshire, water years 2000-03

USGS Publications Warehouse

Harte, Philip T.

2005-01-01

The Milford-Souhegan glacial-drift (MSGD) aquifer, in south-central New Hampshire, is an important source of industrial, commercial, and domestic water. The MSGD aquifer was also an important source of drinking water for the town of Milford until it was found to contain high concentrations of volatile organic compounds (VOCs) in the Savage and Keyes municipal-supply wells in the early 1980s. A VOC plume was found to cover part of the southwestern half of the MSGD aquifer. In September 1984, the site was designated a Superfund site, called the Savage Municipal Well Superfund site. The primary source area of contaminants was a former tool manufacturing facility (called the OK Tool facility, and now called the Operable Unit 1 (OU1) area) that disposed of solvents at the surface and in the subsurface. The facility was closed in 1987 and removed in 1998. A low-permeability containment barrier wall was constructed and installed in the overburden (MSGD aquifer) in 1998 to encapsulate the highest concentrations of VOCs, and a pump-and-treat remediation facility was also added. Remedial operations of extraction and injection wells started in May 1999. A network of water-level monitoring sites was implemented in water year 2000 (October 1, 1999, through September 30, 2000) in the OU1 area to help assess the effectiveness of remedial operations to mitigate the VOC plume, and to evaluate the effect of the barrier wall and remedial operations on the hydraulic connections across the barrier and between the overburden and underlying bedrock. Remedial extraction and injections wells inside and outside the barrier help isolate ground-water flow inside the barrier and the further spreading of VOCs. This report summarizes both continuous and selected periodic manual measurements of water level and physical water properties (specific conductance and water temperature) for 10 monitoring locations during water years 2000-03. Additional periodic manual measurements of water levels were

Brownfields Projects in EPA's Pacific Southwest

EPA Pesticide Factsheets

Project fact sheet focusing on brownfields-funding that has helped the redevelopment of unused, contaminated sites into usable, public areas - especially in underserved, overburdened and economically distressed locations.

40 CFR 264.302 - Action leakage rate.

Code of Federal Regulations, 2011 CFR

2011-07-01

... design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction, operation... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.302 - Action leakage rate.

Code of Federal Regulations, 2012 CFR

2012-07-01

... design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction, operation... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.302 - Action leakage rate.

Code of Federal Regulations, 2014 CFR

2014-07-01

... design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction, operation... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.302 - Action leakage rate.

Code of Federal Regulations, 2013 CFR

2013-07-01

... design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction, operation... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.252 - Action leakage rate.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.252 - Action leakage rate.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.252 - Action leakage rate.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.252 - Action leakage rate.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

An Overburdened Term: Dewey's Concept of "Experience" as Curriculum Theory

ERIC Educational Resources Information Center

Seaman, Jayson; Nelsen, Peter J.

2011-01-01

This article examines Dewey's concept of "experience" in light of his analysis of industrial capitalism, his anthropological thinking, and his critique of early 20th century educational ideologies, giving the concept a more expansive meaning than what is typically represented in the educational literature. We also outline the specific curricular…

40 CFR 264.222 - Action leakage rate.

Code of Federal Regulations, 2012 CFR

2012-07-01

... uncertainties in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 265.255 - Action leakage rates.

Code of Federal Regulations, 2013 CFR

2013-07-01

... for uncertainties in the design (e.g., slope, hydraulic conductivity, thickness of drainage material... layover and creep of synthetic components of the system, overburden pressures, etc.). (c) To determine if...

40 CFR 264.222 - Action leakage rate.

Code of Federal Regulations, 2013 CFR

2013-07-01

... uncertainties in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 264.222 - Action leakage rate.

Code of Federal Regulations, 2011 CFR

2011-07-01

... uncertainties in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

40 CFR 265.222 - Action leakage rate.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., hydraulic conductivity, thickness of drainage material), construction, operation, and location of the LDS... components of the system, overburden pressures, etc.). (c) To determine if the action leakage rate has been...

40 CFR 264.222 - Action leakage rate.

Code of Federal Regulations, 2014 CFR

2014-07-01

... uncertainties in the design (e.g., slope, hydraulic conductivity, thickness of drainage material), construction... and creep of synthetic components of the system, overburden pressures, etc.). (b) To determine if the...

Method for gasification of deep, thin coal seams. [DOE patent

DOEpatents

Gregg, D.W.

1980-08-29

A method of gasification of coal in deep, thin seams by using controlled bending subsidence to confine gas flow to a region close to the unconsumed coal face is given. The injection point is moved sequentially around the perimeter of a coal removal area from a production well to sweep out the area to cause the controlled bending subsidence. The injection holes are drilled vertically into the coal seam through the overburden or horizontally into the seam from an exposed coal face. The method is particularly applicable to deep, thin seams found in the eastern United States and at abandoned strip mines where thin seams were surface mined into a hillside or down a modest dip until the overburden became too thick for further mining.

Method for gasification of deep, thin coal seams

DOEpatents

Gregg, David W.

1982-01-01

A method of gasification of coal in deep, thin seams by using controlled bending subsidence to confine gas flow to a region close to the unconsumed coal face. The injection point is moved sequentially around the perimeter of a coal removal area from a production well to sweep out the area to cause the controlled bending subsidence. The injection holes are drilled vertically into the coal seam through the overburden or horizontally into the seam from an exposed coal face. The method is particularly applicable to deep, thin seams found in the eastern United States and at abandoned strip mines where thin seams were surface mined into a hillside or down a modest dip until the overburden became too thick for further mining.

EJ 2020 Action Agenda: EPA’s Environmental Justice Strategy

EPA Pesticide Factsheets

The EJ 2020 Action Agenda is EPA's strategic plan for integrating environmental justice into its programs, policies, and activities and will support making a difference in overburdened, underserved, and economically distressed communities.

Anchorage Behaviors of Frictional Tieback Anchors in Silty Sand

NASA Astrophysics Data System (ADS)

Hsu, Shih-Tsung; Hsiao, Wen-Ta; Chen, Ke-Ting; Hu, Wen-Chi; Wu, Ssu-Yi

2017-06-01

Soil anchors are extensively used in geotechnical applications, most commonly serve as tieback walls in deep excavations. To investigate the anchorage mechanisms of this tieback anchor, a constitutive model that considers both strain hardening and softening and volume dilatancy entitled SHASOVOD model, and FLAC3D software are used to perform 3-D numerical analyses. The results from field anchor tests are compared with those calculated by numerical analyses to enhance the applicability of the numerical method. After the calibration, this research carried out the parameter studies by numerical analyses. The numerical results reveal that whether the yield of soil around an anchor develops to ground surface and/or touches the diaphragm wall depending on the overburden depth H and the embedded depth Z of an anchor, this study suggests the minimum overburden and embedded depths to avoid the yield of soils develop to ground surface and/or touch the diaphragm wall. When the embedded depth, overburden depth or fixed length of an anchor increases, the anchorage capacity also increases. Increasing fixed length should be the optimum method to increase the anchorage capacity for fixed length less than 20m. However, when the fixed length of an anchor exceeds 30 m, the increasing rate of anchorage capacity per fixed length decreases, and progressive yield occurs obviously between the fixed length and surrounding soil.

Empirical analysis of electromagnetic profiles for groundwater prospecting in rural areas of Ibadan, southwestern Nigeria

NASA Astrophysics Data System (ADS)

Ehinola, O. A.; Opoola, A. O.

2005-05-01

The Slingram electromagnetic (EM) survey using a coil separation of 60 and 100 meters was carried out in 10 villages in Akinyele area of Ibadan, southwestern Nigeria to aid in the development of groundwater. Five main rock types including an undifferentiated gneiss complex (Su), biotite-garnet schist/gneiss (Bs), quartzite and quartz schist (Q), migmatised undifferentiated biotite/hornblende gneiss (M) and pegmatite/quartz vein (P) underlie the study area. A total of 31 EM profiles was made to accurately locate prospective borehole sites in the field. Four main groups with different behavioural pattern were categorized from the EM profiles. Group 1 is characterized by high density of positive (HDP) or high density of negative (HDN) real and imaginary curves, Group 2 by parallel real and imaginary curves intersecting with negligible amplitude (PNA), Group 3 by frequent intersection of high density of negative minima (FHN) real and imaginary curves, and Group 4 by separate and approximately parallel (SAP) real and imaginary curves. Qualitative pictures of the overburden thickness and the extent of fracturing have been proposed from these behavioural patterns. A comparison of the borehole yield with the overburden thickness and the level of fracturing show that borehole yield depends more on the fracture density than on the overburden thickness. Asymmetry of the anomaly was also found useful in the determination of the inclination of the conductor/fracture.

Appraisal of an Array TEM Method in Detecting a Mined-Out Area Beneath a Conductive Layer

NASA Astrophysics Data System (ADS)

Li, Hai; Xue, Guo-qiang; Zhou, Nan-nan; Chen, Wei-ying

2015-10-01

The transient electromagnetic method has been extensively used for the detection of mined-out area in China for the past few years. In the cases that the mined-out area is overlain by a conductive layer, the detection of the target layer is difficult with a traditional loop source TEM method. In order to detect the target layer in this condition, this paper presents a newly developed array TEM method, which uses a grounded wire source. The underground current density distribution and the responses of the grounded wire source TEM configuration are modeled to demonstrate that the target layer is detectable in this condition. The 1D OCCAM inversion routine is applied to the synthetic single station data and common middle point gather. The result reveals that the electric source TEM method is capable of recovering the resistive target layer beneath the conductive overburden. By contrast, the conductive target layer cannot be recovered unless the distance between the target layer and the conductive overburden is large. Compared with inversion result of the single station data, the inversion of common middle point gather can better recover the resistivity of the target layer. Finally, a case study illustrates that the array TEM method is successfully applied in recovering a water-filled mined-out area beneath a conductive overburden.

Surface and downhole shear wave seismic methods for thick soil site investigations

USGS Publications Warehouse

Hunter, J.A.; Benjumea, B.; Harris, J.B.; Miller, R.D.; Pullan, S.E.; Burns, R.A.; Good, R.L.

2002-01-01

Shear wave velocity-depth information is required for predicting the ground motion response to earthquakes in areas where significant soil cover exists over firm bedrock. Rather than estimating this critical parameter, it can be reliably measured using a suite of surface (non-invasive) and downhole (invasive) seismic methods. Shear wave velocities from surface measurements can be obtained using SH refraction techniques. Array lengths as large as 1000 m and depth of penetration to 250 m have been achieved in some areas. High resolution shear wave reflection techniques utilizing the common midpoint method can delineate the overburden-bedrock surface as well as reflecting boundaries within the overburden. Reflection data can also be used to obtain direct estimates of fundamental site periods from shear wave reflections without the requirement of measuring average shear wave velocity and total thickness of unconsolidated overburden above the bedrock surface. Accurate measurements of vertical shear wave velocities can be obtained using a seismic cone penetrometer in soft sediments, or with a well-locked geophone array in a borehole. Examples from thick soil sites in Canada demonstrate the type of shear wave velocity information that can be obtained with these geophysical techniques, and show how these data can be used to provide a first look at predicted ground motion response for thick soil sites. ?? 2002 Published by Elsevier Science Ltd.

Analytic Study of Three-Dimensional Rupture Propagation in Strike-Slip Faulting with Analogue Models

NASA Astrophysics Data System (ADS)

Chan, Pei-Chen; Chu, Sheng-Shin; Lin, Ming-Lang

2014-05-01

Strike-slip faults are high angle (or nearly vertical) fractures where the blocks have moved along strike way (nearly horizontal). Overburden soil profiles across main faults of Strike-slip faults have revealed the palm and tulip structure characteristics. McCalpin (2005) has trace rupture propagation on overburden soil surface. In this study, we used different offset of slip sandbox model profiles to study the evolution of three-dimensional rupture propagation by strike -slip faulting. In strike-slip faults model, type of rupture propagation and width of shear zone (W) are primary affecting by depth of overburden layer (H), distances of fault slip (Sy). There are few research to trace of three-dimensional rupture behavior and propagation. Therefore, in this simplified sandbox model, investigate rupture propagation and shear zone with profiles across main faults when formation are affecting by depth of overburden layer and distances of fault slip. The investigators at the model included width of shear zone, length of rupture (L), angle of rupture (θ) and space of rupture. The surface results was follow the literature that the evolution sequence of failure envelope was R-faults, P-faults and Y-faults which are parallel to the basement fault. Comparison surface and profiles structure which were curved faces and cross each other to define 3-D rupture and width of shear zone. We found that an increase in fault slip could result in a greater width of shear zone, and proposed a W/H versus Sy/H relationship. Deformation of shear zone showed a similar trend as in the literature that the increase of fault slip resulted in the increase of W, however, the increasing trend became opposite after a peak (when Sy/H was 1) value of W was reached (small than 1.5). The results showed that the W width is limited at a constant value in 3-D models by strike-slip faulting. In conclusion, this study helps evaluate the extensions of the shear zone influenced regions for strike

Time-lapse seismic waveform modelling and attribute analysis using hydromechanical models for a deep reservoir undergoing depletion

NASA Astrophysics Data System (ADS)

He, Y.-X.; Angus, D. A.; Blanchard, T. D.; Wang, G.-L.; Yuan, S.-Y.; Garcia, A.

2016-04-01

Extraction of fluids from subsurface reservoirs induces changes in pore pressure, leading not only to geomechanical changes, but also perturbations in seismic velocities and hence observable seismic attributes. Time-lapse seismic analysis can be used to estimate changes in subsurface hydromechanical properties and thus act as a monitoring tool for geological reservoirs. The ability to observe and quantify changes in fluid, stress and strain using seismic techniques has important implications for monitoring risk not only for petroleum applications but also for geological storage of CO2 and nuclear waste scenarios. In this paper, we integrate hydromechanical simulation results with rock physics models and full-waveform seismic modelling to assess time-lapse seismic attribute resolution for dynamic reservoir characterization and hydromechanical model calibration. The time-lapse seismic simulations use a dynamic elastic reservoir model based on a North Sea deep reservoir undergoing large pressure changes. The time-lapse seismic traveltime shifts and time strains calculated from the modelled and processed synthetic data sets (i.e. pre-stack and post-stack data) are in a reasonable agreement with the true earth models, indicating the feasibility of using 1-D strain rock physics transform and time-lapse seismic processing methodology. Estimated vertical traveltime shifts for the overburden and the majority of the reservoir are within ±1 ms of the true earth model values, indicating that the time-lapse technique is sufficiently accurate for predicting overburden velocity changes and hence geomechanical effects. Characterization of deeper structure below the overburden becomes less accurate, where more advanced time-lapse seismic processing and migration is needed to handle the complex geometry and strong lateral induced velocity changes. Nevertheless, both migrated full-offset pre-stack and near-offset post-stack data image the general features of both the overburden and

Characterization of a suspected terrestrial deep groundwater discharge area on the Canadian Precambrian Shield

NASA Astrophysics Data System (ADS)

Sheppard, Marsha I.; Thibault, D. H.; Milton, G. M.; Reid, J. A. K.; Smith, P. A.; Stevens, K.

1995-03-01

Underground storage and disposal of hazardous wastes require an understanding of groundwater flow and the ability to locate recharge and discharge. Usually, recharge and discharge occur at a transition zone where dispersion/advection, molecular diffusion and biogeochemical processes control the fate of a contaminants leaving an underground facility. Appropriate landscape modelling for risk assessment cannot proceed until this interface is well defined and groundwater discharge can be mapped. Although discharge locations have traditionally been thought of as aquatic, the presence of animal licks suggests the possibility of terrestrial discharge. We have characterized a suspected terrestrial discharge, a well-used deer lick, (1) physically, through surficial mapping, and vegetation and soil profile analyses; (2) geophysically, through magnetic and very low-frequency electromagnetic tilt-angle surveys; (3) hydrogeologically, through water-table elevation measurements; (4) geochemically, through overburden analyses for 238U, 226Ra, 210Pb, Na, tritium, Cl and 36{Cl}/{Cl} atom ratios, as well as pore-water and groundwater analyses for pH, electrical conductivity (EC) and major anions and cations; and (5) thermally, through overburden-rock interface temperatures. Halophytic plants and sedges contained more Na, Cl and 238U than averages reported in the literature. Lineament alignment, coincident with elevated groundwater EC, supported the presence and position of a subsurface fracture. Groundwater chemistry suggested that interfering runoff from a nearby ridge masked the chemical signatures expected of deep groundwater but attest to the weak and possibly ephemeral nature of this discharge. Interpretation of the geochemical data was supported by solute transport modelling. Good agreement between the predictions using an unsaturated soil model, a simple wetland compartment model and the observed profile implied that evapotranspiration, seasonal water-table fluctuations and

34. DETAILS OF CAISSON FOR PIERS 2, 3, 4 AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. DETAILS OF CAISSON FOR PIERS 2, 3, 4 AND 5 TO BE BUILT ON SOIL OVERBURDEN - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

Preliminary report on the lignite resources of the Niobe area, Burke and Ward counties, North Dakota

USGS Publications Warehouse

Owen, Hal E.

1977-01-01

Two lignite beds, the Niobe and the Bonus, occur at strippable depths within the Niobe area. The Niobe bed averages 5 feet (1.5 meters) in thickness and the Bonus bed averages 8 feet (2.4 meters) in thickness. These beds lie in the lower part of the Sentinel Butte Member of the Fort Union Formation (Paleocene). The demonstrated resources of both beds combined is 122 million tons (110 million tonnes), all of which are under less than 120 feet (37 meters) of overburden. The overburden consists of glacial till and shale. The lateral continuity of the coal has been locally interrupted by faulting, glacial outwash channels, and erosion. Folding and/or faulting occurs parallel to the Missouri Coteau escarpment and faulting occurs roughly perpendicular to the escarpment.

Regional collaboration in transport infrastructure provision : the case of Denver's FasTracks rail transit program.

DOT National Transportation Integrated Search

2011-06-01

Cities across the United States are grappling with a looming transportation crisis as a : result of ever-increasing passenger and freight transport demands and overburdened : networks of aging infrastructure. All levels of government, but particularl...

GIS-Mapping and Statistical Analyses to Identify Climate-Vulnerable Communities and Populations Exposed to Superfund Sites

EPA Science Inventory

Climate change-related cumulative health risks are expected to be disproportionately greater for overburdened communities, due to differential proximity and exposures to chemical sources and flood zones. Communities and populations vulnerable to climate change-associated impacts ...

EPA’s Environmental Justice Research Roadmap and Interagency Efforts on Climate Justice

EPA Science Inventory

Stressors associated with climate change are expected to be disproportionately greater for overburdened communities. This webinar will present activities of the Climate Impacts subcommittee of the Federal Interagency Working Group (IWG) on Stressors associated with climate chang...

30 CFR 715.14 - Backfilling and grading.

Code of Federal Regulations, 2010 CFR

2010-07-01

... required to— (i) Retain all overburden and spoil on the solid portion of existing or new benches; and (ii... case may highwalls be left as part of terraces. (iv) Culverts and underground rock drains shall be used...

Empirical analysis of electromagnetic profiles for groundwater prospecting in rural areas of Ibadan, southwestern Nigeria

NASA Astrophysics Data System (ADS)

Ehinola, O. A.; Opoola, A. O.; Adesokan, H. A.

2006-04-01

The Slingram electromagnetic (EM) survey using a coil separation of 60 and 100 m was carried out in ten villages in the Akinyele area of Ibadan, southwestern Nigeria to aid in the development of groundwater. Five main rock types including an undifferentiated gneiss complex (Su), biotite-garnet schist/gneiss (Bs), quartzite and quartz schist (Q), migmatized undifferentiated biotite/hornblende gneiss (M) and pegmatite/quartz vein (P) underlie the study area. A total of 31 EM profiles was made to accurately locate prospective borehole sites in the field. Four main groups with different behavioural patterns were categorized from the EM profiles. Group 1 is characterized by a high density of positive (HDP) or a high density of negative (HDN) real and imaginary curves, Group 2 by parallel real and imaginary curves intersecting with negligible amplitude (PNA), Group 3 by frequent intersection of a high density of negative minima (FHN) real and imaginary curves, and Group 4 by separate and approximately parallel (SAP) real and imaginary curves. Qualitative pictures of the overburden thickness and the extent of fracturing have been proposed from these behavioural patterns. A comparison of the borehole yield with the overburden thickness and the level of fracturing shows that the borehole yield depends more on the fracture density than on the overburden thickness. The asymmetry of the anomaly was also found to be useful in the determination of the inclination of the conductor/fracture.

Thermal Effect on Fracture Integrity in Enhanced Geothermal Systems

NASA Astrophysics Data System (ADS)

Zeng, C.; Deng, W.; Wu, C.; Insall, M.

2017-12-01

In enhanced geothermal systems (EGS), cold fluid is injected to be heated up for electricity generation purpose, and pre-existing fractures are the major conduits for fluid transport. Due to the relative cold fluid injection, the rock-fluid temperature difference will induce thermal stress along the fracture wall. Such large thermal stress could cause the failure of self-propping asperities and therefore change the fracture integrity, which could affect the heat recovery efficiency and fluid recycling. To study the thermal effect on fracture integrity, two mechanisms pertinent to thermal stress are proposed to cause asperity contact failure: (1) the crushing between two pairing asperities leads to the failure at contact area, and (2) the thermal spalling expedites this process. Finite element modeling is utilized to investigate both failure mechanisms by idealizing the asperities as hemispheres. In the numerical analysis, we have implemented meso-scale damage model to investigate coupled failure mechanism induced by thermomechanical stress field and original overburden pressure at the vicinity of contact point. Our results have shown that both the overburden pressure and a critical temperature determine the threshold of asperity failure. Since the overburden pressure implies the depth of fractures in EGS and the critical temperature implies the distance of fractures to the injection well, our ultimate goal is to locate a region of EGS where the fracture integrity is vulnerable to such thermal effect and estimate the influences.

Lick Run: Green Infrastructure in Cincinnati and Beyond

EPA Science Inventory

By capturing and redistributing rain water or runoff in plant-soil systems such as green roofs, rain gardens or swales, green infrastructure restores natural hydrologic cycles and reduces runoff from overburdened gray infrastructure. Targeted ecosystem restoration, contaminant fi...

How to Get Some Fiber in Your System.

ERIC Educational Resources Information Center

Sturgeon, Julie

1998-01-01

Describes one Kansas school district's efforts to connect all the classrooms in 23 schools through computers, and to do so with wiring that would not become overburdened. The decision-making process to use fiber optics is examined. (GR)

Lateral extrusion of a thermally weakened pluton overburden (Campiglia Marittima, Tuscany)

NASA Astrophysics Data System (ADS)

Vezzoni, Simone; Rocchi, Sergio; Dini, Andrea

2017-10-01

The ascent and emplacement of magmas in the upper crust modify the local pre-existing thermal and rheological settings. Such changes have important effects in producing anomalous structures, mass extrusion, rock fracturing, and in some conditions, hydrothermal mineralizations. In the Campiglia Marittima area, detailed field mapping led to the reconstruction of a local deformation history that overlaps, chronologically and spatially, with regional extension. This local deformation was triggered at the Miocene-Pliocene boundary by the intrusion of a monzogranitic pluton beneath a carbonate sedimentary sequence. The emplacement of the pluton produced a perturbation in the rheological behaviour of the carbonate host rocks, producing transient ductile conditions in the very shallow crust. The carbonate rocks were thermally weakened and flowed laterally, accumulating downslope of the pluton roof, mainly toward the east. As the thermal anomaly was decaying, the brittle-ductile boundary moved progressively back towards the pluton, and large tension gash-shaped volumes of fractured marble were generated. These fractured volumes were exploited by rising hydrothermal fluids generating sigmoidal skarn bodies and ore shoots. This work presents the Campiglia Marittima case study as a prime example of structural interference between regional extensional structures and local, lateral mass extrusion in a transient ductile rheological regime triggered by pluton emplacement.

Three-phase heaters with common overburden sections for heating subsurface formations

DOEpatents

Vinegar, Harold J [Bellaire, TX

2012-02-14

A heating system for a subsurface formation is described. The heating system includes three substantially u-shaped heaters with first end portions of the heaters being electrically coupled to a single, three-phase wye transformer and second end portions of the heaters being electrically coupled to each other and/or to ground. The three heaters may enter the formation through a first common wellbore and exit the formation through a second common wellbore so that the magnetic fields of the three heaters at least partially cancel out in the common wellbores.

Lateral extrusion of a thermally weakened pluton overburden (Campiglia Marittima, Tuscany)

NASA Astrophysics Data System (ADS)

Vezzoni, Simone; Rocchi, Sergio; Dini, Andrea

2018-06-01

The ascent and emplacement of magmas in the upper crust modify the local pre-existing thermal and rheological settings. Such changes have important effects in producing anomalous structures, mass extrusion, rock fracturing, and in some conditions, hydrothermal mineralizations. In the Campiglia Marittima area, detailed field mapping led to the reconstruction of a local deformation history that overlaps, chronologically and spatially, with regional extension. This local deformation was triggered at the Miocene-Pliocene boundary by the intrusion of a monzogranitic pluton beneath a carbonate sedimentary sequence. The emplacement of the pluton produced a perturbation in the rheological behaviour of the carbonate host rocks, producing transient ductile conditions in the very shallow crust. The carbonate rocks were thermally weakened and flowed laterally, accumulating downslope of the pluton roof, mainly toward the east. As the thermal anomaly was decaying, the brittle-ductile boundary moved progressively back towards the pluton, and large tension gash-shaped volumes of fractured marble were generated. These fractured volumes were exploited by rising hydrothermal fluids generating sigmoidal skarn bodies and ore shoots. This work presents the Campiglia Marittima case study as a prime example of structural interference between regional extensional structures and local, lateral mass extrusion in a transient ductile rheological regime triggered by pluton emplacement.

Efficiency of Low-Profile External Dumping at Open Pit Coal Mining in Kemerovo Region

NASA Astrophysics Data System (ADS)

Selyukov, Alexey; Ermolaev, Vyacheslav; Kostinez, Irina

2017-11-01

Kemerovo region is one of the largest industrial regions of Russia, with a raw material specialization. The rapid growth of the coal industry in recent years has been greatly facilitated by the expansion and development of open pit mining for coal seams extraction, accompanied by an increase in the volumes of overburden and the height of the dumps. There are about 400 objects in the Russian Federation Government Register of Waste Disposal Facilities 80% of which are dumps. Approaches both to external dumping and to the technical stage of reclamation currently contribute to the growth of geomorphic system's instability. Thus, it is proposed to slightly change the approaches to external dumping: the essence consists in the formation of an external dump of overburden, which in future would represent a favorable landscape unit of a flat surface relief used for subsequent differently directed purposes.

Shale oil recovery process

DOEpatents

Zerga, Daniel P.

1980-01-01

A process of producing within a subterranean oil shale deposit a retort chamber containing permeable fragmented material wherein a series of explosive charges are emplaced in the deposit in a particular configuration comprising an initiating round which functions to produce an upward flexure of the overburden and to initiate fragmentation of the oil shale within the area of the retort chamber to be formed, the initiating round being followed in a predetermined time sequence by retreating lines of emplaced charges developing further fragmentation within the retort zone and continued lateral upward flexure of the overburden. The initiating round is characterized by a plurality of 5-spot patterns and the retreating lines of charges are positioned and fired along zigzag lines generally forming retreating rows of W's. Particular time delays in the firing of successive charges are disclosed.

BioStar: an online question & answer resource for the bioinformatics community

USDA-ARS?s Scientific Manuscript database

Although the era of big data has produced many bioinformatics tools and databases, using them effectively often requires specialized knowledge. Many groups lack bioinformatics expertise, and frequently find that software documentation is inadequate and local colleagues may be overburdened or unfamil...

76 FR 13401 - Environmental Impact Statements; Notice of Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-11

... Mine Pits, Haul Roads, Water Management Structures, and Overburden Disposal Areas, Implementation..., Final EIS, TVA, KY, Tennessee Valley Authority (TVA) Integrated Resource Plan (IRP), To Address the... Activities, Proposal to Support and Conduct Current, Emerging, and Future Training Activities, Implementation...

On the physics of frequency domain controlled source electromagnetics in shallow water, 2: transverse anisotropy

NASA Astrophysics Data System (ADS)

Chave, Alan D.; Mattsson, Johan; Everett, Mark E.

2017-11-01

In recent years, marine controlled source electromagnetics (CSEM) has found increasing use in hydrocarbon exploration due to its ability to detect thin resistive zones beneath the seafloor. It is the purpose of this paper to evaluate the physics of CSEM for an ocean whose electrical thickness is comparable to or much thinner than that of the overburden using the in-line configuration through examination of the elliptically-polarized seafloor electric field, the time-averaged energy flow depicted by the real part of the complex Poynting vector, energy dissipation through Joule heating and the Fréchet derivatives of the seafloor field with respect to the sub-seafloor conductivity that is assumed to be transversely anisotropic, with a vertical-to-horizontal resistivity ratio of 3:1. For an ocean whose electrical thickness is comparable to that of the overburden, the seafloor electromagnetic response for a model containing a resistive reservoir layer has a greater amplitude and reduced phase as a function of offset compared to that for a halfspace, or a stronger and faster response, and displays little to no evidence for the air interaction. For an ocean whose electrical thickness is much smaller than that of the overburden, the electric field displays a greater amplitude and reduced phase at small offsets, shifting to a stronger amplitude and increased phase at intermediate offsets, and a weaker amplitude and enhanced phase at long offsets, or a stronger and faster response that first changes to stronger and slower, and then transitions to weaker and slower. By comparison to the isotropic case with the same horizontal conductivity, transverse anisotropy stretches the Poynting vector and the electric field response from a thin resistive layer to much longer offsets. These phenomena can be understood by visualizing the energy flow throughout the structure caused by the competing influences of the dipole source and guided energy flow in the reservoir layer, and the air

Fault and fracture patterns around a strike-slip influenced salt wall

NASA Astrophysics Data System (ADS)

Alsop, G. I.; Weinberger, R.; Marco, S.; Levi, T.

2018-01-01

The trends of faults and fractures in overburden next to a salt diapir are generally considered to be either parallel to the salt margin to form concentric patterns, or at right angles to the salt contact to create an overall radial distribution around the diapir. However, these simple diapir-related patterns may become more complex if regional tectonics influences the siting and growth of a diapir. Using the Sedom salt wall in the Dead Sea Fault system as our case study, we examine the influence of regional strike-slip faulting on fracture patterns around a salt diapir. This type of influence is important in general as the distribution and orientation of fractures on all scales may influence permeability and hence control fluid and hydrocarbon flow. Fractures adjacent to the N-S trending salt wall contain fibrous gypsum veins and injected clastic dykes, attesting to high fluid pressures adjacent to the diapir. Next to the western flank of the salt wall, broad (∼1000 m) zones of upturn or 'drape folds' are associated with NW-SE striking conjugate extensional fractures within the overburden. Within 300 m of the salt contact, fracture patterns in map view display a progressive ∼30°-35° clockwise rotation with more NNW-SSE strikes immediately adjacent to the salt wall. While some extensional faults display growth geometries, indicating that they were syn-depositional and initiated prior to tilting of beds associated with drape folding, other fractures display increasing dips towards the salt, suggesting that they have formed during upturn of bedding near the diapir. These observations collectively suggest that many fractures developed to accommodate rotation of beds during drape folding. Extensional fractures in the overburden define a mean strike that is ∼45° anticlockwise (counter-clockwise) of the N-S trending salt wall, and are therefore consistent with sinistral transtension along the N-S trending Sedom Fault that underlies the salt wall. Our outcrop

Estimating Last Glacial Maximum Ice Thickness Using Porosity and Depth Relationships: Examples from AND-1B and AND-2A Cores, McMurdo Sound, Antarctica

NASA Astrophysics Data System (ADS)

Hayden, T. G.; Kominz, M. A.; Magens, D.; Niessen, F.

2009-12-01

We have estimated ice thicknesses at the AND-1B core during the Last Glacial Maximum by adapting an existing technique to calculate overburden. As ice thickness at Last Glacial Maximum is unknown in existing ice sheet reconstructions, this analysis provides constraint on model predictions. We analyze the porosity as a function of depth and lithology from measurements taken on the AND-1B core, and compare these results to a global dataset of marine, normally compacted sediments compiled from various legs of ODP and IODP. Using this dataset we are able to estimate the amount of overburden required to compact the sediments to the porosity observed in AND-1B. This analysis is a function of lithology, depth and porosity, and generates estimates ranging from zero to 1,000 meters. These overburden estimates are based on individual lithologies, and are translated into ice thickness estimates by accounting for both sediment and ice densities. To do this we use a simple relationship of Xover * (ρsed/ρice) = Xice; where Xover is the overburden thickness, ρsed is sediment density (calculated from lithology and porosity), ρice is the density of glacial ice (taken as 0.85g/cm3), and Xice is the equalivant ice thickness. The final estimates vary considerably, however the “Best Estimate” behavior of the 2 lithologies most likely to compact consistently is remarkably similar. These lithologies are the clay and silt units (Facies 2a/2b) and the diatomite units (Facies 1a) of AND-1B. These lithologies both produce best estimates of approximately 1,000 meters of ice during Last Glacial Maximum. Additionally, while there is a large range of possible values, no combination of reasonable lithology, compaction, sediment density, or ice density values result in an estimate exceeding 1,900 meters of ice. This analysis only applies to ice thicknesses during Last Glacial Maximum, due to the overprinting effect of Last Glacial Maximum on previous ice advances. Analysis of the AND-2A

40 CFR 232.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING 404 PROGRAM DEFINITIONS... mining-related materials;” after the words “utility lines; and artificial reefs. (2) In addition..., overburden from mining or other excavation activities, and materials used to create any structure or...

40 CFR 232.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING 404 PROGRAM DEFINITIONS... mining-related materials;” after the words “utility lines; and artificial reefs. (2) In addition..., overburden from mining or other excavation activities, and materials used to create any structure or...

40 CFR 232.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING 404 PROGRAM DEFINITIONS... mining-related materials;” after the words “utility lines; and artificial reefs. (2) In addition..., overburden from mining or other excavation activities, and materials used to create any structure or...

RAPTR-SV: a hybrid method for the detection of structural variants

USDA-ARS?s Scientific Manuscript database

Motivation: Identification of Structural Variants (SV) in sequence data results in a large number of false positive calls using existing software, which overburdens subsequent validation. Results: Simulations using RAPTR-SV and another software package that uses a similar algorithm for SV detection...

Performance measures for sustainable freight movement.

DOT National Transportation Integrated Search

2012-02-01

Freight movement by road and rail is a cornerstone of the economy of the United States. However, the movement of freight in the U.S. is increasingly impacted by congestion, overburdened infrastructure, and economic issues. Thus, there is a need to em...

THERMAL REMEDIATION

EPA Science Inventory

Thermal remediation is being proposed by Region I for remediation of the overburden soil and groundwater at the Solvent Recovery Services New England Superfund site. This presentation at the public meeting will acquaint area residents with thermal remediation. The two types of ...

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

Morgan, W.C.; Schermerhorn, J.G.

Recently passed federal strip mining legislation in the USA officially emphasizes that the increased coal production required by the United States through surface mining is going to be obtained only with stricter environmental standards. Dozing overburden down the hillside in Appalachian contour mining or leaving dragline spoils in area mining is now taboo and it is now, or will soon be, necessary to return the disturbed land to as good or better condition than before mining. These new restrictions will create a need for new and better ways to do the job. This article describes one approach for utilizing scrapersmore » and dozers to strip all of the overburden and to replace it in an environmentally satisfactory fashion. The objective was to do this at a lower cost than that possible with the traditional dragline system by using dozers and scrapers for reclamation and topsoil handling.« less

An assessment of the effect of supersonic aircraft operations on the stratospheric ozone content

NASA Technical Reports Server (NTRS)

Poppoff, I. G.; Whitten, R. C.; Turco, R. P.; Capone, L. A.

1978-01-01

An assessment of the potential effect on stratospheric ozone of an advanced supersonic transport operations is presented. This assessment, which was undertaken because of NASA's desire for an up-to-date evaluation to guide programs for the development of supersonic technology and improved aircraft engine designs, uses the most recent chemical reaction rate data. From the results of the present assessment it would appear that realistic fleet sizes should not cause concern with regard to the depletion of the total ozone overburden. For example, the NOx emission of one type designed to cruise at 20 km altitude will cause the ozone overburden to increase by 0.03% to 0.12%, depending upon which vertical transport is used. These ozone changes can be compared with the predictions of a 1.74% ozone decrease (for 100 Large SST's flying at 20 km) made in 1974 by the FAA's Climatic Impact Assessment Program.

Frost heave susceptibility of saturated soil under constant rate of freezing

NASA Astrophysics Data System (ADS)

Ryokai, K.; Iguro, M.; Yoneyama, K.

Introduced are the results of experiments carried out to quantitatively obtain the frost heave pressure and displacement of soil subjected to artificial freezing or freezing around in-ground liquefied natural gas storage tanks. This experiment is conducted to evaluate the frost heave susceptibility of saturated soil under overconsolidation. In other words, this experiment was carried out to obtain the relation of the over-burden pressure and freezing rate to the frost heave ratio by observing the frost heave displacement and freezing time of specimens by freezing the specimens at a constant freezing rate under a constant overburden pressure, while letting water freely flow in and out of the system. Introduced are the procedures for frost heave test required to quantitatively obtain the frost heave displacement and pressure of soil. Furthermore, the relation between the frost heave susceptibility and physical properties of soil obtained by this test is reported.

Geochemistry and migration of contaminants at the Weldon Spring chemical plant site, St. Charles County, Missouri, 1989-91

USGS Publications Warehouse

Schumacher, John G.

1993-01-01

The geochemistry of the shallow aquifer and geochemical controls on the migration of uranium and other constituents from raffinate pits were determined at the Weldon Spring chemical plant site. Surface-water samples from the raffinate pits con- tained large concentrations of calcium, magnesium, sodium, potassium, sulfate, nitrite, lithium, moly- bdenum, strontium, vanadium, and uranium. Analyses of interstitial-water samples from raffinate pit 3 indicated that concentrations of most constituents increased with increasing depth below the water- sediment interface. Nitrate and uranium were not chemically reduced and attenuated within the raffinate pits and can be expected to migrate into the overburden. Laboratory sorption experiments were performed to evaluate the effect of pH value on the sorption of several raffinate constituents by the overburden. No sorption of calcium, sodium, sulfate, nitrate, or lithium was observed. Sorption of molybdenum was dependent on solution pH and sorption of uranium was dependent on solution pH and carbonate concentration. The sorption of uranium and molybdenum was consistent with sorption controlled by oxyhydroxides. The quality of water collected in overburden lysimeters near raffinate pit 4 can be modeled as a mixture of water from raffinate pits 3 and 4, and an uncontaminated com- ponent in a system at equilibrium with ferrihydrite and calcite. Increased constituent concentrations in a perennial spring north of the site were the result of a subsurface connection between the spring and several losing stream segments receiving runoff from the site, in addition to seepage from the raffinate pits.

INTEGRATED WASTE AND WATER MANAGEMENT PROJECT (IWWMP) &NDASH; BATANGAS, PHILIPPINES

EPA Science Inventory

Mass evacuations of rural residents in the Philippines to large urban areas overburden an already strained infrastructure. There have been investments by non-profit groups to develop housing to attract the evacuees back to their regions. However, there remains a great need for...

Grading and Academic Freedom: An English Academic's Angle on Hill's Contentious Triangle

ERIC Educational Resources Information Center

Buglear, John

2011-01-01

Following the dismissal of a Canadian professor over disputed grading practices, Hill produced his triangle model of competing interests of academics, administrators and students. In the UK, academic freedom in relation to grading is increasingly constrained reflecting more assertive institutional management supervising over-burdened academic…

Health Information Technology: Dos and Don'ts for Today and Tomorrow.

PubMed

Sidorov, Jaan; Randhar, Akash

2017-01-01

The challenges include not overburdening physicians and fitting into an increasingly complex, multilayered informatics ecosystem. Innovative health care entities that neglect health care's reliance on evidence-based medicine and go to market without the benefit of any peer review do so at their own peril.

Utilizing a State Level Volunteer Recognition Program at the County Level

ERIC Educational Resources Information Center

McCall, Fran Korthaus; Culp, Ken, III

2013-01-01

Volunteer recognition is an important component of Extension programs. Most land-grant universities have implemented a state volunteer recognition program. Extension professionals, however, are too overburdened with meetings, programs, and activities to effectively recognize volunteers locally. Utilizing a state model is an efficient means of…

Instructional Supervision and Curriculum Monitoring: Reinterpreting the Principal's Role through the Arts of Inquiry

ERIC Educational Resources Information Center

Brooks, Nancy J.; Solloway, Sharon G.; Allen, Louise Anderson

2007-01-01

The gulf between educational leadership theory and contemporary curriculum scholarship is becoming increasingly problematic now that principals have been legally mandated to add curriculum monitoring to their duties as instructional leaders. Lacking familiarity with curriculum theory and practice, many overburdened administrators are turning to…

77 FR 45968 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-02

... (soil and groundwater) of the properties proposed for deletion. DATES: This direct final partial... site media, including soil and groundwater for the following properties: Properties owned by the Town... streams were finally directed to the WWTP. As a result of these discharges, overburden soil and bedrock...

75 FR 47482 - National Oil and Hazardous Substance Pollution Contingency Plan; National Priorities List...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-06

..., groundwater, and soil gas. The PRPs, through their consultants, Benchmark Environmental Engineering and... November 2000 to December 2003 and the final RI report was submitted to EPA in February 2005. The chemicals... boundary located more that 500 feet across the wetland. Site-related chemicals in the overburden...

Unequal Exposure

ERIC Educational Resources Information Center

Roach, Ronald

2005-01-01

For nearly three decades, the environmental justice movement has attracted thousands of activists, scholars and ordinary citizens to mobilize on behalf of communities that have been overburdened with hazardous waste sites, petrochemical plants, incinerators, lead contamination, polluted air and contaminated drinking water. In many cases, activists…

COPEing With Environmental Education Program Development and Infusion into the Global Studies Curricula of Rural Schools.

ERIC Educational Resources Information Center

Peters, Richard O.

An environmental education-oriented global studies program to promote attitudes of environmental stewardship can be implemented in K-12 rural school systems, as an integrated part of social studies instruction, without overburdening the curriculum, by using the Curriculum Organization and Program Evaluation (COPE) model. The model provides…

Two Generations at Risk: Child Welfare, Institutional Boundaries, and Family Violence in Grandparent Homes

ERIC Educational Resources Information Center

Day, Susan E.; Bazemore, Gordon

2011-01-01

Participation of extended family members, particularly custodial grandparents, has generally resulted in better outcomes for abused children and relief for an overburdened child welfare system. This research explores the risk of adolescent perpetrated violence in custodial grandparent households with data from the Florida Department of Juvenile…

Espace

ERIC Educational Resources Information Center

De Volder, Maurice; Slootmaker, Aad; Kurvers, Hub; Rutjens, Marjo; van der Baaren, John; Bitter, Marlies; Kappe, Rutger; Roossink, Henk; de Goeijen, Jan; Reitzema, Hans

2007-01-01

This article describes Espace (Electronic System for Peer Assessment and Coaching Efficiency), a student peer-feedback tool that enhances the educational quality of assignments without overburdening faculty or adding administrative costs. Developed and tested by four universities in the Netherlands, Espace focuses on qualitative feedback and…

Effect of routine mental health screening in a low-resource pediatric primary care population.

PubMed

Berger-Jenkins, Evelyn; McCord, Mary; Gallagher, Trish; Olfson, Mark

2012-04-01

Despite evidence for its feasibility, the usage of mental health screening in primary care practices with overburdened providers and few referral options remains unclear. This study explores the effects of routine screening on mental health problem identification and management in a low-resource setting. Medical records of 5 to 12 year-old children presenting for well visits before and after screening was implemented were reviewed. Multivariate logistic regression was used to explore associations between study period and identification/management practices. Changes in the number of visits and wait times for a co-located referral service were assessed post hoc. Parents disclosed more mental health problems, and providers initiated more workups but referred fewer patients after screening was implemented. The proportion of new visits and wait times for the referral service did not change. Even in low-resource settings, screening may facilitate parental disclosure and increase clinical attention to mental health problems without overburdening referral services.

Process of breaking and rendering permeable a subterranean rock mass

DOEpatents

Lekas, Mitchell A.

1980-01-01

The process of the present invention involves the following steps: producing, as by hydrofracing, a substantially horizontal fracture in the subterranean rock mass to be processed; emplacing an explosive charge in the mass in spaced juxtaposed position to the fracture; enlarging the fracture to create a void space thereat, an initial lifting of the overburden, and to provide a free face juxtaposed to and arranged to cooperate with the emplaced explosive charge; and exploding the charge against the free face for fragmenting the rock and to distribute the space, thus providing fractured, pervious, rubble-ized rock in an enclosed subterranean chamber. Firing of the charge provides a further lifting of the overburden, an enlargement of the chamber and a larger void space to distribute throughout the rubble-ized rock within the chamber. In some forms of the invention an explosive charge is used to produce a transitory enlargement of the fracture, and the juxtaposed emplaced charge is fired during the critical period of enlargement of the fracture.

Basin F Overburden and Soil Sampling and Analysis Study, Rocky Mountain Arsenal

DTIC Science & Technology

1982-05-01

boring sites will be es:ablished via standard :and surveyinS procedures. 3.3 Bor-ng/ Samaling Procidures Upon staking/marking of the bore holes, the folloi...procedure until the interferences have been eliminated. 3.2.2 Samale Testing Step OC (6) (Procedure Blank) The procedure blank consists of the

Adaptive Adjustment in Taraxacum Officinale Wigg. in the Conditions of Overburden Dump

NASA Astrophysics Data System (ADS)

Legoshchina, Olga; Egorova, Irina; Neverova, Olga

2017-11-01

Morphological and anatomical features of the leaves and roots of Taraxacum officinale Wigg., growing under the conditions of the rocky dump of the Kedrovsky coal mine of the Kemerovo region, were studied. It was revealed that the specific environmental conditions of the dump cause morphological and anatomical changes in the leaves and roots of the dandelion. At the level of morphology, a decrease in the average leaf area, a thickening of leaf blades, a tendency to decrease the number of leaves in the rosette, a significant decrease in the mass and length of the roots. At the level of the anatomical structure of the leaves, there is a significant increase in the thickness of the mesophyll, a tendency to decrease the thickness of the tissues of the upper and lower epidermis, a decrease in the number of cells in 1 mm2 and an increase in the size of stomata in the tissues of the lower and upper epidermis, a decrease in the number of stomata by 1 mm2 and a stomatal index on the upper epidermis. At the level of the anatomical structure of the roots, the radius of the root decreases, the radius of the cortex and phloem, the diameter of the xylem.

Regional investigations of soil and overburden analysis and plant uptake of metals

USGS Publications Warehouse

Gough, L.P.

1984-01-01

Regional studies on the bioavailability of metals at native and disturbed sites were conducted over the past seven years by the USGS. The work was concentrated in the Fort Union, Powder River, and Green River coal resource regions where measures of extractable metals in soils were found to have limited use in predicting metal levels in plants. Correlations between Cu, Fe, and Zn in plants and extractable (DTPA, EDTA, and oxalate) or total levels in native A- and C-horizons of soil were occasionally significant. A simple linear model is generally not adequate, however, in estimating element uptake by plants. Prediction capabilities were improved when a number of soil chemical and physical parameters were included as independent variables in a stepwise linear multiple regression analysis; however, never more than 54% of the total variability in the data was explained by the equations for these metals. Soil pH was the most important variable relating soil chemistry to plant chemistry. This relation was always positive and apparently a response to soil levels of metal carbonates and not Fe and Mn oxides. Studies that compared the metal uptake by rehabilitation species to extractable (DTPA) metal levels in mice soils produced similar results. ?? 1984 Science and Technology Letters.

UNDERSTANDING THE IMPACT OF ENVIRONMENTAL VARIABLES ON THE LEACHING OF MERCURY-CONTAMINATED MINE WASTES FROM THE SULFUR BANK MERCURY MINE, CLEAR LAKE, CA

EPA Science Inventory

For nearly a century, Clear Lake in northern California has received inputs of mercury (Hg) mining wastes trom the Sulfur Bank Mercury Mine (SBMM). About 1.2 million tons of Hg-contaminated overburden and mine tailings were distributed over a 50-ha surface area due to mining oper...

75 FR 75847 - 40th Anniversary of the Environmental Protection Agency

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-07

...-energy alternatives to fossil fuels. The advances we make today will build a sustainable future for our... effect on our public health, the well-being of future generations, and the vitality of our economy. Just... for environmental justice in overburdened communities, and confronting global climate change. The work...

78 FR 52967 - Notice of Intent To Initiate Public Scoping and Prepare an Environmental Impact Statement for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-27

... acres (4,287 acres would be disturbed by the mining operations, highwall reduction, soil storage, scoria... WECo currently uses in other permitted areas of the Rosebud Mine. In advance of each mining pass, soil... expose the coal seam. Overburden stockpiles, soil stockpiles, and scoria pits would be developed adjacent...

EFFECT OF PH AND REDOX CONDITIONS ON DESTABILIZATION OF MINING WASTES CONTAINING MERCURY

EPA Science Inventory

Clear Lake in Northern California has received inputs of mercury mining wastes from the Sulfur Bank Mercury Mine. About 1.2M tons of Hg-contaminated overburden and mine tailings were distributed over a 50-ha surface area due to mining operations from 1865-1957. The SBMM ws placed...

Web-Based Surveys Facilitate Undergraduate Research and Knowledge

ERIC Educational Resources Information Center

Grimes, Paul, Ed.; Steele, Scott R.

2008-01-01

The author presents Web-based surveying as a valuable tool for achieving quality undergraduate research in upper-level economics courses. Web-based surveys can be employed in efforts to integrate undergraduate research into the curriculum without overburdening students or faculty. The author discusses the value of undergraduate research, notes…

Light Satellites - A Dilemma for the U.S. Army

DTIC Science & Technology

1988-12-01

current systems would be siqnificantly overburdened by the need of our national leadeship to qain intelliqence over wide areas of the globe very...January 1988. Contract MDA 903-85-C-0049. ANSER, Arlington, Va. 3. Boutacoff, David A. "Army Banks on Joint STARS for Airland Battle Management

Meteorological and constituent data for January and February 1981

NASA Technical Reports Server (NTRS)

1981-01-01

Balloon data consisting of a plot showing the mixing ratio of ozone partial pressure in micromillibors and temperature in degrees centigrade versus pressure altitude in millibars is presented. An accompanying tabulation of meteorological and constituent data is also presented. The total overburden was aquired by Dobson Spectrophotometer 72.

Survival and growth of trees and shrubs on different lignite minesoils in Louisiana

Treesearch

James D. Haywood; Allan E. Tiarks; James P. Barnett

1993-01-01

In 1980, an experimental opencast lignite mine was developed to compare redistributed A horizon with three minesoil mixtures as growth media for woody plants. The three minesoil mixtures contained different amounts and types of overburden materials, and normal reclamation practices were followed. Loblolly pine (Pinus taeda, L.), sawtooth oak (

Joint Tomographic Imaging of 3-­-D Density Structure Using Cosmic Ray Muons and High-­-Precision Gravity Data

NASA Astrophysics Data System (ADS)

Rowe, C. A.; Guardincerri, E.; Roy, M.; Dichter, M.

2015-12-01

As part of the CO2 reservoir muon imaging project headed by the Pacific Northwest National Laboraory (PNNL) under the U.S. Department of Energy Subsurface Technology and Engineering Research, Development, and Demonstration (SubTER) iniative, Los Alamos National Laboratory (LANL) and the University of New Mexico (UNM) plan to leverage the recently decommissioned and easily accessible Tunnel Vault on LANL property to test the complementary modeling strengths of muon radiography and high-precision gravity surveys. This tunnel extends roughly 300 feet into the hillside, with a maximum depth below the surface of approximately 300 feet. We will deploy LANL's Mini Muon Tracker (MMT), a detector consisting of 576 drift tubes arranged in alternating parallel planes of orthogonally oriented tubes. This detector is capable of precise determination of trajectories for incoming muons with angular resolution of a few milliradians. We will deploy the MMT at several locations within the tunnel, to obtain numerous crossing muon trajectories and permit a 3D tomographic image of the overburden to be built. In the same project, UNM will use a Scintrex digital gravimeter to collect high-precision gravity data from a dense grid on the hill slope above the tunnel as well as within the tunnel itself. This will provide both direct and differential gravity readings for density modeling of the overburden. By leveraging detailed geologic knowledge of the canyon and the lithology overlying the tunnel, as well as the structural elements, elevations and blueprints of the tunnel itself, we will evaluate the muon and gravity data both independently and in a simultaneous, joint inversion to build a combined 3D density model of the overburden.

Response of a Circular Tunnel Through Rock to a Harmonic Rayleigh Wave

NASA Astrophysics Data System (ADS)

Kung, Chien-Lun; Wang, Tai-Tien; Chen, Cheng-Hsun; Huang, Tsan-Hwei

2018-02-01

A factor that combines tunnel depth and incident wavelength has been numerically determined to dominate the seismic responses of a tunnel in rocks that are subjected to harmonic P- and S-waves. This study applies the dynamic finite element method to investigate the seismic response of shallow overburden tunnels. Seismically induced stress increments in the lining of a circular tunnel that is subjected to an incident harmonic R-wave are examined. The determination of R-wave considers the dominant frequency of acceleration history of the 1999 Chi-Chi earthquake measured near the site with damage to two case tunnels at specifically shallow depth. An analysis reveals that the normalized seismically induced axial, shear and flexural stress increments in the lining of a tunnel reach their respective peaks at the depth h/ λ = 0.15, where the ground motion that is generated by an incident of R-wave has its maximum. The tunnel radius has a stronger effect on seismically induced stress increments than does tunnel depth. A greater tunnel radius yields higher normalized seismically induced axial stress increments and lower normalized seismically induced shear and flexural stress increments. The inertia of the thin overburden layer above the tunnel impedes the propagation of the wave and affects the motion of the ground around the tunnel. With an extremely shallow overburden, such an effect can change the envelope of the normalized seismically induced stress increments from one with a symmetric four-petal pattern into one with a non-symmetric three-petal pattern. The simulated results may partially elucidate the spatial distributions of cracks that were observed in the lining of the case tunnels.

Estimated trichloroethene transformation rates due to naturally occurring biodegradation in a fractured-rock aquifer

USGS Publications Warehouse

Chapelle, Francis H.; Lacombe, Pierre J.; Bradley, Paul M.

2012-01-01

Rates of trichloroethene (TCE) mass transformed by naturally occurring biodegradation processes in a fractured rock aquifer underlying a former Naval Air Warfare Center (NAWC) site in West Trenton, New Jersey, were estimated. The methodology included (1) dividing the site into eight elements of equal size and vertically integrating observed concentrations of two daughter products of TCE biodegradation–cis-dichloroethene (cis-DCE) and chloride–using water chemistry data from a network of 88 observation wells; (2) summing the molar mass of cis-DCE, the first biodegradation product of TCE, to provide a probable underestimate of reductive biodegradation of TCE, (3) summing the molar mass of chloride, the final product of chlorinated ethene degradation, to provide a probable overestimate of overall biodegradation. Finally, lower and higher estimates of aquifer porosities and groundwater residence times were used to estimate a range of overall transformation rates. The highest TCE transformation rates estimated using this procedure for the combined overburden and bedrock aquifers was 945 kg/yr, and the lowest was 37 kg/yr. However, hydrologic considerations suggest that approximately 100 to 500 kg/yr is the probable range for overall TCE transformation rates in this system. Estimated rates of TCE transformation were much higher in shallow overburden sediments (approximately 100 to 500 kg/yr) than in the deeper bedrock aquifer (approximately 20 to 0.15 kg/yr), which reflects the higher porosity and higher contaminant mass present in the overburden. By way of comparison, pump-and-treat operations at the NAWC site are estimated to have removed between 1,073 and 1,565 kg/yr of TCE between 1996 and 2009.

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

Burwood, R.; Fortems, G.; Mycke, B.

Deposited under lacustrine conditions during the rift-phase opening of the southern Atlantic, the lower Congo Bucomazi Formation is a highly productive source rock sequence. Reaching considerable thickness (1.8 km), a heterogeneous organofacies reflects both rapid accumulation and changing conditions during Early Cretaceous Barremian sedimentation. As a component of organofacies, low resolution studies showed kerogen kinetic parameters (Ea/A) varied widely according to the gross paleoenvironmental conditions prevailing during deposition. As a a general trend, refractory (type I, higher Ea) kerogens of the [open quotes]basin fill[close quotes] Organic Rich Zone (ORZ) give way to more labile (type II, lower Ea) assemblages inmore » the up-section [open quotes]sheet drape[close quotes] sediments. At higher resolution, a considerable fine structure in Ea fluctuation, presumably reflecting micropaleoenvironment control, becomes evident. Using Ea values assembled for the Bucomazi type section, subsidence modeling for a Ponta Vermelha depocenter section showed a wide disparity in behavior. Being more representative of the sheet-drape episode, type II assemblages matured earlier, at lesser overburdens, and provided the initial hydrocarbon charge. For the ORZ assemblages, the dominant type I component was of retarded maturation, only becoming productive at commensurately greater overburdens. Cumulatively, these events merge to provide an extended period of hydrocarbon generation with implications for production of aggregate oils of varied emplacement histories. Significantly, the net effect of the observed Ea contrast results in the less prolific (but more labile) uppermost Bucomazi assuming a more important charging role than the ORZ of superior source richness. The latter can only realize its full potential under the greatest overburdens attainable in the most subsident depocenters.« less

Induced Seismicity Monitoring of an Underground Salt Cavern Prone to Collapse

NASA Astrophysics Data System (ADS)

Mercerat, E. D.; Driad-Lebeau, L.; Bernard, P.

2010-02-01

Within the framework of a large research project launched to assess the feasibility of microseismic monitoring of growing underground caverns, this specific work focuses on the analysis of the induced seismicity recorded in a salt mine environment. A local seismic network has been installed over an underground salt cavern located in the Lorraine basin (Northeast of France). The microseismic network includes four 3-components and three single component geophones deployed at depths between 30 and 125 m in cemented boreholes drilled in the vicinity of the study area. The underground cavern under monitoring is located within a salt layer at 180 m depth and it presents a rather irregular shape that can be approximated by a cylindrical volume of 50 m height and 180 m diameter. Presently, the cavern is full of saturated brine inducing a significant pressure on its walls (~2.0 MPa) to keep the overburden mechanically stable. Nevertheless some small microseismic events were recorded by the network and analyzed (approximately 2,000 events in 2 years of recording). In October 2005 and April 2007, two controlled pressure transient experiments were carried out in the cavern, in order to analyze the mechanical response of the overburden by tracking the induced microseismicity. The recorded events were mainly grouped in clusters of 3-30 s of signal duration with emergent first arrivals and rather low frequency content (between 20 and 120 Hz). Some of these events have been spatially located by travel-time picking close to the actual cavern and its immediate roof. Preliminary spectral analysis of isolated microearthquakes suggests sources with non-negligible tensile components possibly related to fluid-filled cracks. Rock-debris falling into the cavern from delamination of clay marls in the immediate roof is probably another source of seismic excitation. This was later confirmed when the most important seismic swarms occurred at the site during May 2007, accompanied by the

The Tax Base And The Tax Bill. Tax Implications of Development: A Workbook.

ERIC Educational Resources Information Center

Brighton, Deb; Northup, Jim

The property tax base in Vermont's towns are overburdened as property taxes are usually the only funding method available to finance schools, police departments, highway work, recreation programs, and government in general. Attempting to offer their citizens a balanced program of services without exorbitant taxes, local officials are striving to…

The Facebook Generation: Homework as Social Networking

ERIC Educational Resources Information Center

Kitsis, Stacy M.

2008-01-01

Overburdened with athletics, play rehearsals, band practice, volunteer work, after-school jobs, friendships, and--if their parents are lucky--quality time with their families, it is hardly surprising that even the most dedicated students resent homework as an incursion on their time. Meanwhile, their teachers watch the growing stacks of unread…

Why Do New Teachers Leave? How Could They Stay?

ERIC Educational Resources Information Center

Simos, Elaine

2013-01-01

The author of this article posits that some teachers leave the profession because they entered it with unrealistic expectations, and that the reality of multiple preparations, unpaid orientation sessions, and large student loads is overburdening.for new teachers. Many new teachers leave their positions because of the dissonance between their…

GEOCHEMICAL EVOLUTION OF GROUND WATER AND TRANSPORT OF MERCURY AT THE SULPHUR BANK MERCURY MINE SUPERFUND SITE IN NORTHERN CALIFORNIA, USA

EPA Science Inventory

The Sulphur Bank Mercury Mine, located on the shore of Clear Lake, Lake County, California, is a potential source for a modern-day mercury flux into the local aquatic ecosystem. Surface mining created the Herman Pit, a 9.3 ha open pit with a depth > 30 m, while overburden and pr...

Teaching New Vocabulary to Iranian Young FL Learners: Using Two Methods Total Physical Response and Keyword Method

ERIC Educational Resources Information Center

Toghyani Khorasgani, Amir; Khanehgir, Mansour

2017-01-01

Early language learning for children is increasingly common, and the majority of parents and the public do not see it as superfluous or overburdening children. Moreover, teaching a foreign language to very young children has been an increasingly dominant trend in most globalized societies. While there is abundant literature that supports teaching…

Teaching New Vocabulary to Young Learners: Using Two Methods Total Physical Response and Keyword Method

ERIC Educational Resources Information Center

Khorasgani, Amir Toghyani; Khanehgir, Mansour

2017-01-01

Early language learning for children is increasingly common, and the majority of parents and the public do not see it as superfluous or overburdening children. Moreover, teaching a foreign language (FL) to very young children has been an increasingly dominant trend in most globalized societies. While there is abundant literature that supports…

To What Extent Do Certain Characteristics of a Child's Written Story Influence the Way It Is Rated? Insights into Features Necessary for Supporting Struggling Writers

ERIC Educational Resources Information Center

Grünke, Mathias; Büyüknarci, Özlem; Wilbert, Jürgen; Breuer, Esther

2015-01-01

Many students exhibit a special type of learning disability in writing. Yet, teachers spend relatively little time helping children and youth with severe writing difficulties overcome their struggles or prevent emerging problems from becoming more severe. A major reason for this lack of attention is that many educators feel overburdened by the…

Evidence for remotely triggered micro-earthquakes during salt cavern collapse

NASA Astrophysics Data System (ADS)

Jousset, P.; Rohmer, J.

2012-04-01

Micro-seismicity is a good indicator of spatio-temporal evolution of physical properties of rocks prior to catastrophic events like volcanic eruptions or landslides and may be triggered by a number of causes including dynamic characteristics of processes in play or/and external forces. Micro-earthquake triggering has been in the recent years the subject of intense research and our work contribute to showing further evidence of possible triggering of micro-earthquakes by remote large earthquakes. We show evidence of triggered micro-seismicity in the vicinity of an underground salt cavern prone to collapse by a remote M~7.2 earthquake, which occurred ~12000 kilometres away. We demonstrate the near critical state of the cavern before the collapse by means of 2D axisymmetric elastic finite-element simulations. Pressure was lowered in the cavern by pumping operations of brine out of the cavern. We demonstrate that a very small stress increase would be sufficient to break the overburden. High-dynamic broadband records reveal a remarkable time-correlation between a dramatic increase of the local high-frequency micro-seismicity rate associated with the break of the stiffest layer stabilizing the overburden and the passage of low-frequency remote seismic waves, including body, Love and Rayleigh surface waves. Stress oscillations due to the seismic waves exceeded the strength required for the rupture of the complex media made of brine and rock triggering micro-earthquakes and leading to damage of the overburden and eventually collapse of the salt cavern. The increment of stress necessary for the failure of a Dolomite layer is of the same order or magnitude as the maximum dynamic stress magnitude observed during the passage of the earthquakes waves. On this basis, we discuss the possible contribution of the Love and Rayleigh low-frequency surfaces waves.

Whole-School Management Issues Concerning the PE Department: "A Natural Division of Labour?"

ERIC Educational Resources Information Center

Williams, Gareth Mark; Williams, Dean

2013-01-01

Utilising the labour ideas of Adam Smith and Emile Durkheim as a theoretical basis, the main objective of this study was to investigate the perception that Heads of Physical Education (HoPE) face unique management and leadership challenges. Results showed that HoPE believe that they are overburdened with tasks primarily involving the delegation of…

36 CFR 6.7 - Mining wastes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Mining wastes. 6.7 Section 6... DISPOSAL SITES IN UNITS OF THE NATIONAL PARK SYSTEM § 6.7 Mining wastes. (a) Solid waste from mining includes but is not limited to mining overburden, mining byproducts, solid waste from the extraction...

Help Desk Is Spelled: R-O-I

ERIC Educational Resources Information Center

Villano, Matt

2009-01-01

Protecting one's institution's technology assets and resources is all about maximizing return on those investments--and that means driving users to take full advantage of new technology rollouts, and not sapping or overburdening help desk resources because users are not fully versed in and encouraged to use new tools. That means one will need to…

English Clubs: Introducing English to Young Learners

ERIC Educational Resources Information Center

Afia, Jawida Ben

2006-01-01

This article introduces an approach taken in Tunisia to introduce English as a foreign language to children in primary school classrooms. The author states that in Tunisia, children in primary schools are first taught Arabic and then French. The government does not want to overburden the students with English learning. Then, the author describes…

The environmental costs of mountaintop mining valley fill operations for aquatic ecosystems of the Central Appalachians.

PubMed

Bernhardt, Emily S; Palmer, Margaret A

2011-03-01

Southern Appalachian forests are recognized as a biodiversity hot spot of global significance, particularly for endemic aquatic salamanders and mussels. The dominant driver of land-cover and land-use change in this region is surface mining, with an ever-increasing proportion occurring as mountaintop mining with valley fill operations (MTVF). In MTVF, seams of coal are exposed using explosives, and the resulting noncoal overburden is pushed into adjacent valleys to facilitate coal extraction. To date, MTVF throughout the Appalachians have converted 1.1 million hectares of forest to surface mines and buried more than 2,000 km of stream channel beneath mining overburden. The impacts of these lost forests and buried streams are propagated throughout the river networks of the region as the resulting sediment and chemical pollutants are transmitted downstream. There is, to date, no evidence to suggest that the extensive chemical and hydrologic alterations of streams by MTVF can be offset or reversed by currently required reclamation and mitigation practices. © 2011 New York Academy of Sciences.

Seulimeum segment characteristic indicated by 2-D resistivity imaging method

NASA Astrophysics Data System (ADS)

Syukri, M.; Saad, R.

2017-06-01

The study conducted at Aceh (Indonesia) within Krueng Raya and Ie Seu Um vicinity with the same geology setting (Lam Teuba volcanic), to study Seulimeum Segment characteristic using 2-D resistivity imaging method. The 2-D resistivity survey applied Pole-dipole array with minimum electrode spacing of 2 and 5 m for Ie Seu Um study area, while 10 m for Krueng Raya area. Resistivity value of Ie Seu Um study area has been correlated and validated with existing outcrops and hot springs which the value used to identify overburden, saturated area and bedrock of Krueng Raya area. The resistivity value of overburden in Krueng Raya area was identify as <30 Ohm.m, bedrock is >30 Ohm.m and saturated zone is <9 Ohm.m. The imaging results used to identify the Seulimeum segment system, where the depth is increasing from southern part (20-50 m) to northern part (50-200 m) when approaching the Andaman Sea and breaks into two sections to produce horst and graben system which indicate that it produced from the moving plat.

Estimate of Cosmic Muon Background for Shallow Underground Neutrino Detectors

NASA Astrophysics Data System (ADS)

Casimiro, E.; Simão, F. R. A.; Anjos, J. C.

One of the severe limitations in detecting neutrino signals from nuclear reactors is that the copious cosmic ray background imposes the use of a time veto upon the passage of the muons to reduce the number of fake signals due to muon-induced spallation neutrons. For this reason neutrino detectors are usually located underground, with a large overburden. However there are practical limitations that do restrain from locating the detectors at large depths underground. In order to decide the depth underground at which the Neutrino Angra Detector (currently in preparation) should be installed, an estimate of the cosmogenic background in the detector as a function of the depth is required. We report here a simple analytical estimation of the muon rates in the detector volume for different plausible depths, assuming a simple plain overburden geometry. We extend the calculation to the case of the San Onofre neutrino detector and to the case of the Double Chooz neutrino detector, where other estimates or measurements have been performed. Our estimated rates are consistent.

Improving School Leadership. Volume 1: Policy and Practice

ERIC Educational Resources Information Center

OECD Publishing (NJ3), 2008

2008-01-01

As countries strive to reform education systems and improve student results, school leadership is high on education policy agendas. But in many countries, the men and women who run schools are overburdened, underpaid and near retirement. And few people are lining up for their jobs. Based on an OECD study of school leadership practices and policies…

Foundation Considerations in Siting of Nuclear Facilities in Karst Terrains and Other Areas Susceptible to Ground Collapse.

DTIC Science & Technology

1981-05-01

Page Time of occurrence .... ............. ... 159 Effect of precipitation .. ........ ... 159 Types of overburden strata .. ......... ... 159...fill the void space between allochems and/or terrigenous grains; usually orthochems are precipitated authigene- tically or during early diagenesis. (d...m Chemical deposits These include the familiar stalagmites, stalactites, "cave flowers," and tufa, which have been chemically precipitated by

CASA Fact Sheet.

ERIC Educational Resources Information Center

National Court Appointed Special Advocate Association, Seattle WA.

Each year nearly 400,000 children in the United States are thrust into court through no fault of their own. Often these children also become victims of the United States' overburdened child welfare system. A Court Appointed Special Advocate (CASA) volunteer is a trained citizen who is appointed by a judge to represent the best interests of a child…

Military Hazardous Wastes: An Overview and Analysis.

DTIC Science & Technology

1981-12-01

the soil as fertilizers or soil conditioners * Mining overburden returned to the mine site Utility wastes (fly ash, flue gas desulfurization sludge...19 3.3.2 What Is the Significance of Superfund to Military Wastes? ...... ............... 20 3.4 Toxic Substances Control Act...Hazardous Wastes From Current and Future Operations .... ......... 34 4.4 Organizational Responsibilities ... ............. .. 42 5. CONTROL TECHNOLOGY

Tenure, Academic Freedom, and the Career I Once Loved

ERIC Educational Resources Information Center

Kolodny, Annette

2008-01-01

Given the financial burden they are taking on, parents and students are not interested in debates over tenure or academic freedom lest these distract them from the immediate goal of preparing to earn a living. Overburdened undergraduates-- students working twenty to forty hours each week to pay the bills and still taking out student loans--greet…

Lexical Evaluation of Teacher-Made Coursebooks: Thai Case Studies of Foundation English Courses at Tertiary Level

ERIC Educational Resources Information Center

Wan-a-rom, Udorn

2012-01-01

Coursebooks as one of the major issues of language teaching/learning instruction can relieve the overburden as well as under-prepared teacher of a great deal of stress, time and additional work. Currently, both commercial and teacher-made English language teaching (ELT) coursebooks are available for use and seem flexible at hands. In any respect,…

43 CFR 23.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Mineral Leasing Act of February 25, 1920, as amended and supplemented (30 U.S.C. 181-287) and the Mineral Leasing Act for Acquired Lands (30 U.S.C. 351-359); (b) Mining Supervisor means the Area Mining Supervisor..., or offer; (d) Overburden means all the earth and other materials which lie above a natural deposit of...

43 CFR 23.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Leasing Act of February 25, 1920, as amended and supplemented (30 U.S.C. 181-287) and the Mineral Leasing Act for Acquired Lands (30 U.S.C. 351-359); (b) Mining Supervisor means the Area Mining Supervisor, or..., or offer; (d) Overburden means all the earth and other materials which lie above a natural deposit of...

43 CFR 23.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Mineral Leasing Act of February 25, 1920, as amended and supplemented (30 U.S.C. 181-287) and the Mineral Leasing Act for Acquired Lands (30 U.S.C. 351-359); (b) Mining Supervisor means the Area Mining Supervisor..., or offer; (d) Overburden means all the earth and other materials which lie above a natural deposit of...

43 CFR 23.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Mineral Leasing Act of February 25, 1920, as amended and supplemented (30 U.S.C. 181-287) and the Mineral Leasing Act for Acquired Lands (30 U.S.C. 351-359); (b) Mining Supervisor means the Area Mining Supervisor..., or offer; (d) Overburden means all the earth and other materials which lie above a natural deposit of...

43 CFR 23.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Mineral Leasing Act of February 25, 1920, as amended and supplemented (30 U.S.C. 181-287) and the Mineral Leasing Act for Acquired Lands (30 U.S.C. 351-359); (b) Mining Supervisor means the Area Mining Supervisor..., or offer; (d) Overburden means all the earth and other materials which lie above a natural deposit of...

International Conference on Case Histories in Geotechnical Engineering (2nd) Held in Rolla, Missouri on 1-5 June 1988. Volume 2

DTIC Science & Technology

1989-06-30

Wright (USA) AAV. Shroff Epoxy Resin (rout System for Solutions to Traditional D.P. Am in (;eotechnical Problems. 5.66...echate Containment System -(eotechnical (U SA ) Considerations . .......................................................... 1577 W D .I. Finn Case...girders were set in place in the formed under co er of tne above ra iling system . clayey overburden by low-frequency vibro-driving methoo, then

OVERBURDEN MINERALOGY AS RELATED TO GROUND-WATER CHEMICAL CHANGES IN COAL STRIP MINING

EPA Science Inventory

A research program was initiated to define and develop an inclusive, effective, and economical method for predicting potential ground-water quality changes resulting from the strip mining of coal in the Western United States. To utilize the predictive method, it is necessary to s...

Groundwater Conditions During 2009 and Changes in Groundwater Levels from 1984 to 2009, Columbia Plateau Regional Aquifer System, Washington, Oregon, and Idaho

USGS Publications Warehouse

Snyder, Daniel T.; Haynes, Jonathan V.

2010-01-01

Groundwater elevations in three basalt units and one unconsolidated hydrogeologic unit in the Columbia Plateau Regional Aquifer System were measured and evaluated to provide a regional overview of groundwater conditions in spring 2009. Water levels for the Saddle Mountains unit, the Wanapum unit, the Grande Ronde unit, and for the overlying Overburden unit were measured in 1,752 wells during spring 2009 by the U.S. Geological Survey (USGS) and 10 other Federal, State, Tribal, and local agencies, including 66 wells located and measured by the USGS specifically for this study. These data were analyzed to determine the presence of spatial correlation of groundwater levels with distance and direction from each other. Groundwater flow in the Palouse Slope structural region showed evidence of being more continuous relative to groundwater flow in the Yakima Fold Belt, where the geologic complexity may contribute to compartmentalization of groundwater flow. This information was used to interpolate the generalized groundwater elevations for each of the basalt hydrogeologic units and to provide information on regional flow. Water-level change maps were constructed for the three basalt hydrogeologic units and the Overburden (unconsolidated) unit. Groundwater levels measured in spring 1984 and 2009 in 470 wells were compared. Small to moderate groundwater-level declines were measured in most wells, although declines greater than 100 ft and as great as 300 ft were measured in many wells. Essentially unchanged groundwater levels were measured in other wells. Of the wells measured in 1984 and 2009, water levels declined in 83 percent of the wells, and declines greater than 25 ft were measured in 29 percent of all wells. The groundwater-level changes were greatest in the deeper hydrogeologic units. Mean groundwater-level changes ranged from a 7 ft decline for the Overburden unit to a 51 ft decline for the Grande Ronde unit. The average annual rates of groundwater-level change for

Internal structure of mushroom-shaped salt diapirs

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

Not Available

1989-01-01

This book focuses on the dynamics and kinematics of salt diapirs with crestal bulbs shaped like a mushroom, one of the most complex types of diapirs, as interpreted by experimental modeling and from naturally occurring examples. Direct, practical applications of this research include use in the evaluation of salt domes as repositories for radioactive waste, in the exploration and production of salt, potash, and sulfur, and in the search for subtle hydrocarbon traps. The authors conducted 8 centrifuge experiments, which produced more than 100 model diapirs. These experiments were dynamically scaled to U.S. Gulf Coast salt domes, but the qualitativemore » results are also relevant to salt diapirs in other provinces and to granitoid diapirs penetrating metamorphic crust. The centrifuged domes grew under overburdens of constant thickness or under aggrading and prograding overburdens, a new experimental approach. Results indicate that external mushroom structure results from toroidal circulation of buoyant source and immediate cover having similar effective viscosities, whereas internal structure is produced by toroidal circulation confined within the diapir. The internal diapir structure elucidates the mechanics of emplacement and indicates whether an external mushroom shape can be expected and sought by further exploration.« less

Three-dimensional geomechanical simulation of reservoir compaction and implications for well failures in the Belridge diatomite

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

Fredrich, J.T.; Argueello, J.G.; Thorne, B.J.

1996-11-01

This paper describes an integrated geomechanics analysis of well casing damage induced by compaction of the diatomite reservoir at the Belridge Field, California. Historical data from the five field operators were compiled and analyzed to determine correlations between production, injection, subsidence, and well failures. The results of this analysis were used to develop a three-dimensional geomechanical model of South Belridge, Section 33 to examine the diatomite reservoir and overburden response to production and injection at the interwell scale and to evaluate potential well failure mechanisms. The time-dependent reservoir pressure field was derived from a three-dimensional finite difference reservoir simulation andmore » used as input to three-dimensional non-linear finite element geomechanical simulations. The reservoir simulation included -200 wells and covered 18 years of production and injection. The geomechanical simulation contained 437,100 nodes and 374,130 elements with the overburden and reservoir discretized into 13 layers with independent material properties. The results reveal the evolution of the subsurface stress and displacement fields with production and injection and suggest strategies for reducing the occurrence of well casing damage.« less

Three-dimensional geomechanical simulation of reservoir compaction and implications for well failures in the Belridge diatomite

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

Fredrich, J.T.; Argueello, J.G.; Thorne, B.J.

1996-12-31

This paper describes an integrated geomechanics analysis of well casing damage induced by compaction of the diatomite reservoir at the Belridge Field, California. Historical data from the five field operators were compiled and analyzed to determine correlations between production, injection, subsidence, and well failures. The results of this analysis were used to develop a three-dimensional geomechanical model of South Belridge, Section 33 to examine the diatomite reservoir and overburden response to production and injection at the interwell scale and to evaluate potential well failure mechanisms. The time-dependent reservoir pressure field was derived from a three-dimensional finite difference reservoir simulation andmore » used as input to three-dimensional non-linear finite element geomechanical simulations. The reservoir simulation included approximately 200 wells and covered 18 years of production and injection. The geomechanical simulation contained 437,100 nodes and 374,130 elements with the overburden and reservoir discretized into 13 layers with independent material properties. The results reveal the evolution of the subsurface stress and displacement fields with production and injection and suggest strategies for reducing the occurrence of well casing damage.« less

In-Flight Performance of the Water Vapor Monitor Onboard the Sofia Observatory

NASA Technical Reports Server (NTRS)

Roellig, Thomas L.; Yuen, Lunming; Sisson, David; Hang, Richard

2012-01-01

NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA) airborne observatory flies in a modified B747-SP aircraft in the lower stratosphere above more than 99.9% of the Earth's water vapor. As low as this residual water vapor is, it will still affect SOFIA's infrared and sub-millimeter astronomical observations. As a result, a heterodyne instrument has been developed to observe the strength and shape of the 1830Hz rotational line of water, allowing measurements of the integrated water vapor overburden in flight. In order to be useful in correcting the astronomical signals, the required measured precipitable water vapor accuracy must be 2 microns or better, 3 sigma, and measured at least once a minute. The Water Vapor Monitor has flown 22 times during the SOFIA Early Science shared-risk period. The instrument water vapor overburden data obtained were then compared with concurrent data from GOES-V satellites to perform a preliminary calibration of the measurements. This presentation will cover the.results of these flights. The final flight calibration necessary to reach the required accuracy will await subsequent flights following the SOFIA observatory upgrade that is taking place during the spring and summer of 2012.

Research of a real-time overload monitoring and response system of bridges and roads

NASA Astrophysics Data System (ADS)

Yu, Yan; Shi, Yan; Zhao, Xuefeng; Ou, Jinping

2012-04-01

Due to the general overloading of vehicles, premature failure of bridges and roads are more and more obvious. Structural behaviors of engineering structures need real-time monitoring and diagnosis, timely detection of structural damage, evaluation of their safety, and necessary precautions, in order to prevent major accident such as the collapse of bridges and roads. But the existing monitoring system, which is very expensive, does not apply to the low budget structures. Therefore, a potable, low-cost, low-power structural monitoring system, which consists of electric resistance strain gauge, collection and execution unit, graph collection system and analysis software, is designed in this paper. The system can collect the critical data about the force of pavement to take the certain judge algorithm. The alarm will be given and the overburden data will be transmitted to IDC to make the further analysis when the pavement is overburden. At the same time, the plates of overweight vehicles can be collected and sent to the relevant departments. The system has the features of simple structure, easy realization, and low cost, which fills the application gaps in structural health monitoring of low-budget project.

The Alberhill and other clay deposits of Temescal Canyon, Riverside County, California

USGS Publications Warehouse

Daviess, Steven Norman; Bramlette, M.N.

1953-01-01

Clay is mined in open pits by several companies in the Alberhill district, and the refractory clays of relatively high alumina sediment are used largely for fire brick. The Alberhill Coal and Clay Company is the largest operator and has produced a little over 2,000,000 tons of clay, of which nearly half was the refractory type. The clay occurs at the contact of the lower Tertiary and the Mesozoic basement complex. The weathered surface of basement rocks includes much clay of high iron and low alumina content, and the better clay occurs in the basal Tertiary sediments. The clay deposits vary rather abruptly in thickness and quality, and only local lenses contain workable deposits. Structural deformation makes dips of 10 to 20 degrees common and the clay strata therefore pitch under excessive overburden in short distances. Extensive deposits of thick alluvial fan deposits cover the clay-bearing strata over most of the area, and add to the overburden problems. The apparent lack of clay deposits of good quality that would total several million tons of ore, and the geological conditions that would make exploration and mining difficult and expensive make this district unpromising.

Areas of ground subsidence due to geofluid withdrawal

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

Grimsrud, G.P.; Turner, B.L.; Frame, P.A.

1978-08-01

Detailed information is provided on four geothermal areas with histories of subsidence. These were selected on the basis of: physical relevance of subsidence areas to high priority US geothermal sites in terms of withdrawn geofluid type, reservoir depth, reservoir geology and rock characteristics, and overburden characteristics; and data completeness, quality, and availability. The four areas are: Chocolate Bayou, Raft River Valley, Wairakei, and the Geysers. (MHR)

Power and Energy Strategy White Paper

DTIC Science & Technology

2010-04-01

and cooling. In recent years, several factors have emerged which further complicate the engineering and logistics challenges associated with power and...equation to maintain US military dominance in support of national security. II. INTRODUCTION Energy was a critical factor during many of the...non-combat platforms, especially for auxiliary power, and the compelling quest for compact, high capacity power sources for our overburdened Soldiers

Geophysical Investigation using Two Dimensional Electrical Resistivity Tomography method to delineate Subsurface Geological Structures at Dudhkoshi-II (230 MW) Hydroelectric Project, Solukhumbu District, Eastern Nepal

NASA Astrophysics Data System (ADS)

Ghimire, H.; Bhusal, U. C.; Khatiwada, B.; Pandey, D.

2017-12-01

Geophysical investigation using two dimensional electrical resistivity tomography (2D-ERT) method plays a significant role in determining the subsurface resistivity distribution by making measurement on the ground surface. This method was carried out at Dudhkoshi-II (230 MW) Hydroelectric Project, lies on Lesser Himalayan region of the Eastern Nepal to delineate the nature of the subsurface geology to assess its suitability for the construction of dam, desanding basin and powerhouse. The main objective of the proposed study consists of mapping vertical as well as horizontal variations of electrical resistivity to enable detection of the boundaries between unconsolidated materials and rocks of the different resistivity, possible geologic structures, such as possible presence of faults, fractures, and voids in intake and powerhouse area. For this purpose, the (WDJD-4 Multi-function Digital DC Resistivity/IP) equipment was used with Wenner array (60 electrodes). To fulfill these objectives of the study, the site area was mapped by Nine ERT profiles with different profile length and space between electrodes was 5 m. The depth of the investigation was 50 m. The acquired data were inverted to tomogram sections using tomographic inversion with RES2DINV commercial software. The Tomography sections show that the subsurface is classified into distinct geo-electric layers of dry unconsolidated overburden, saturated overburden, fractured rock and fresh bedrock of phyllites with quartzite and gneiss with different resistivity values. There were no voids and faults in the study area. Thickness of overburden at different region found to be different. Most of the survey area has bedrock of phyllites with quartzite; gneiss is also present in some location at intake area. Bedrock is found at the varies depth of 5-8 m at dam axis, 20-32 m at desanding basin and 3-10 m at powerhouse area. These results are confirmed and verified by using several boreholes data were drilled on the

Interaction between crustal tectonics and salt deformation in the Eastern Sardinian margin, Western Tyrrhenian Sea: seismic data and analogue modelling

NASA Astrophysics Data System (ADS)

Vendeville, Bruno; Lymer, Gael; Gaullier, Virginie; Chanier, Frank; Maillard, Agnes; Sage, Françoise; Lofi, Johanna; Thinon, Isabelle

2014-05-01

The Tyrrhenian Basin opened by eastward migration of the Apennine subduction system. Rifting along the Eastern Sardinian margin started during the middle to late Miocene times and hence this timing partly overlapped the Messinian Salinity Crisis. The two "METYSS" cruises were conducted to use the deformation of the Messinian salt and its Plio-Quaternary overburden as a proxy for better delineating the tectonic history of the sub-salt basement. Many parts of the study area contain two of the most typical Messinian series of the Western Mediterranean: the Mobile Unit (MU; salt, mainly halite), overlain by the more competent Upper Unit (UU: alternating dolomitic marls and anhydrite). The brittle Plio-Quaternary cover overlies the UU. Usually, the presence of mobile salt is viewed as a nuisance for understanding crustal tectonics because salt's ability to act as a structural buffer between the basement and the cover. However, we illustrate, using examples from the Cornaglia Terrace, how we can use thin-skinned salt tectonics as indicators of vertical movements in the sub-salt, pre-Messinian basement. There, slip along N-S-trending crustal normal faults bounding basement troughs has been recorded by salt and overburden in two different manners: - First, post-salt basement faulting (typically after deposition of the Upper Unit and the early Pliocene), and some crustal-scale southward tilting, triggered along-strike (southward) thin-skinned, gliding of salt and overburden recorded by upslope extension and downslope shortening. - Second, and less obvious at first glance, there was some crustal activity along another basement trough, located East of the Baronie Ridge after deposition of the Messinian salt. This trough is narrow, trends N-S and is bounded by crustal faults. The narrow width of the trough allowed for only minor across-strike (E-W) gliding. The resulting geometry would suggest that nothing happened after Messinian times, but some structural features (confirmed

OCLC book interlibrary loan in a basic-unit hospital library: one year's experience.

PubMed

Landwirth, T K

1983-04-01

Methodist Medical Center of Illinois Medical Library, a "basic-unit" medical library (i.e., not a resource library) in the Regional Medical Library Program recently completed one year of borrowing and lending books using OCLC. Of the books successfully borrowed through OCLC, 79% were obtained from nonmedical libraries. Forming cost-sharing OCLC clusters among basic units makes OCLC an affordable alternative to borrowing books from overburdened medical resource libraries.

OCLC book interlibrary loan in a basic-unit hospital library: one year's experience.

PubMed Central

Landwirth, T K

1983-01-01

Methodist Medical Center of Illinois Medical Library, a "basic-unit" medical library (i.e., not a resource library) in the Regional Medical Library Program recently completed one year of borrowing and lending books using OCLC. Of the books successfully borrowed through OCLC, 79% were obtained from nonmedical libraries. Forming cost-sharing OCLC clusters among basic units makes OCLC an affordable alternative to borrowing books from overburdened medical resource libraries. PMID:6860829

Refinement of Regional Distance Seismic Moment Tensor and Uncertainty Analysis for Source-Type Identification

DTIC Science & Technology

2014-09-02

release; distribution is unlimited. rock zone which provides a pathway for formation fluids, natural gas and crude oil from deeper strata that are... southeast Louisiana (Figure 21). It is a part of the Gulf Coast salt basin which exhibits many salt structures formed by upward flow of sedimentary salt...primarily, evaporites) on account of low density of salt and overburden pressures caused by younger sedimentary deposits (Beckman and Williamson, 1990

Dimensional Analysis of Impulse Loading Resulting from Detonation of Shallow-Buried Charges

DTIC Science & Technology

2013-01-01

lines running along the floor, floor-bolted seats , ammunition storage racks, power-train lines, etc.). MMMS 9,3 368 Traditionally, the floor-rupture...The power of dimensional analysis is that the functional relations offered are generalized, i.e. the effect of geometrical, kinematic , ambient, loading... ejected vdet Explosive detonation velocity L/T A new quantity added which controls the time of sand-overburden bubble burst Charge/plate positioning

The influence of geomorphology on the role of women at artisanal and small-scale mine sites

USGS Publications Warehouse

Malpeli, Katherine C.; Chirico, Peter G.

2013-01-01

The geologic and geomorphic expressions of a mineral deposit determine its location, size, and accessibility, characteristics which in turn greatly influence the success of artisans mining the deposit. Despite this critical information, which can be garnered through studying the surficial physical expression of a deposit, the geologic and geomorphic sciences have been largely overlooked in artisanal mining-related research. This study demonstrates that a correlation exists between the roles of female miners at artisanal diamond and gold mining sites in western and central Africa and the physical expression of the deposits. Typically, women perform ore processing and ancillary roles at mine sites. On occasion, however, women participate in the extraction process itself. Women were found to participate in the extraction of ore only when a deposit had a thin overburden layer, thus rendering the mineralized ore more accessible. When deposits required a significant degree of manual labour to access the ore due to thick overburden layers, women were typically relegated to other roles. The identification of this link encourages the establishment of an alternative research avenue in which the physical and social sciences merge to better inform policymakers, so that the most appropriate artisanal mining assistance programs can be developed and implemented.

Determination of technological parameters in strip mining by time-of-flight and image processing

NASA Astrophysics Data System (ADS)

Elandaloussi, Frank; Mueller, B.; Osten, Wolfgang

1999-09-01

The conveying and dumping of earth masses lying over the coal seam in lignite surface mining is done usually by overburden conveyor bridges. The overburden, obtained from connected excavators, is transported over the bridge construction using a conveyor belt system and poured into one front dump and three surface dumps. The shaping of the dump growth is of great importance both to guaranty the stability of the masses dumped to earth stocks as well as the whole construction and to prepare the area for re-cultivation. This article describes three measurement systems: one to determine the impact point of the dumped earth masses, one to determine the shape of the entire mining process and the other a sensor for the loading of the conveyor belt. For the first measurement system, a real-time video system has been designed, set-up and installed that is capable to determine the impact point of all three dumps simultaneously. The second measurement system is a connection of 5 special designed laser distance measuring instruments, that are able to measure the shape of the mining process under unfavorable environmental conditions like dust, high temperature changes, heavy shocks etc. The third sensor is designed for monitoring the transportation of the masses via the conveyor belt system.

Ground-water hydrology and quality before and after strip mining of a small watershed in Jefferson County, Ohio

USGS Publications Warehouse

Razem, A.C.

1984-01-01

Ground-water conditions before and after surface mining of a small watershed are described as part of a study to determine the effects of mining on hydrologic systems. The watershed was underlain by stratified sedimentary rocks containing local aquifers above shaley clay beds associated with the major coal seams. Mining involved removing the overburden rocks, including most of the top aquifer, stripping the coal, and recontouring the overburden spoils to the approximate premining shape of the watershed. Replacement of the top aquifer by spoils during regrading has caused many changes in recharge and discharge rates, saturated thickness, aquifer characteristics, and water quality. In the middle aquifer there were changes in saturated thickness and water quality. Resaturation of the top-aquifer spoils during and after reclamation has been slow. Saturated thicknesses have ranged from zero initially after mining to 4 feet after 1 1/2 years. Water levels in the middle aquifer have risen from a few feet to 40 feet. Water quality generally has been degraded: concentrations of bicarbonate, calcium, magnesium , chloride, iron, manganese, sulfate, and dissolved solids have increased. Premining water types remained about the same after mining, except for some changes from bicarbonate type to sulfate type. (USGS)

Source and Assessment of Metal Pollution at Khetri Copper Mine Tailings and Neighboring Soils, Rajasthan, India.

PubMed

Punia, Anita; Siddaiah, N Siva; Singh, Saurabh K

2017-11-01

We present here the results of the study on metal pollution by identifying source, abundance and distribution in soil and tailings of Khetri copper complex (KCC) mines, Rajasthan India. The region is highly contaminated by copper (Cu) with higher values in the soil near overburden material (1224 mg/kg) and tailings (111 mg/kg). The average Cu (231 mg/kg) concentration of soil is ~9, 5 and 32 times higher than upper crust, world average shale (WAS) and local background soil (LS), respectively. However this reaches to ~82, 46 and 280 times higher in case of tailing when compared. The correlation and principal component analysis for soil reveals that the source of Cu, Zn, Co, Ni, Mn and Fe is mining and Pb and Cd could be result of weathering of parent rocks and other anthropogenic activities. The source for Cr in soil is both mining activities and weathering of parent rocks. The values of index of geo-accumulation (I geo ) and pollution load index for soil using LS as background are higher compared to values calculated using WAS. The metal rich sulphide bearing overburden material as well as tailings present in the open environment at KCC mines region warrants a proper management to minimize their impact on the environment.

Shallow Gas Migration along Hydrocarbon Wells-An Unconsidered, Anthropogenic Source of Biogenic Methane in the North Sea.

PubMed

Vielstädte, Lisa; Haeckel, Matthias; Karstens, Jens; Linke, Peter; Schmidt, Mark; Steinle, Lea; Wallmann, Klaus

2017-09-05

Shallow gas migration along hydrocarbon wells constitutes a potential methane emission pathway that currently is not recognized in any regulatory framework or greenhouse gas inventory. Recently, the first methane emission measurements at three abandoned offshore wells in the Central North Sea (CNS) were conducted showing that considerable amounts of biogenic methane originating from shallow gas accumulations in the overburden of deep reservoirs were released by the boreholes. Here, we identify numerous wells poking through shallow gas pockets in 3-D seismic data of the CNS indicating that about one-third of the wells may leak, potentially releasing a total of 3-17 kt of methane per year into the North Sea. This poses a significant contribution to the North Sea methane budget. A large fraction of this gas (∼42%) may reach the atmosphere via direct bubble transport (0-2 kt yr -1 ) and via diffusive exchange of methane dissolving in the surface mixed layer (1-5 kt yr -1 ), as indicated by numerical modeling. In the North Sea and in other hydrocarbon-prolific provinces of the world shallow gas pockets are frequently observed in the sedimentary overburden and aggregate leakages along the numerous wells drilled in those areas may be significant.

Fluid pressure arrival time tomography: Estimation and assessment in the presence of inequality constraints, with an application to a producing gas field at Krechba, Algeria

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

Rucci, A.; Vasco, D.W.; Novali, F.

2010-04-01

Deformation in the overburden proves useful in deducing spatial and temporal changes in the volume of a producing reservoir. Based upon these changes we estimate diffusive travel times associated with the transient flow due to production, and then, as the solution of a linear inverse problem, the effective permeability of the reservoir. An advantage an approach based upon travel times, as opposed to one based upon the amplitude of surface deformation, is that it is much less sensitive to the exact geomechanical properties of the reservoir and overburden. Inequalities constrain the inversion, under the assumption that the fluid production onlymore » results in pore volume decreases within the reservoir. We apply the formulation to satellite-based estimates of deformation in the material overlying a thin gas production zone at the Krechba field in Algeria. The peak displacement after three years of gas production is approximately 0.5 cm, overlying the eastern margin of the anticlinal structure defining the gas field. Using data from 15 irregularly-spaced images of range change, we calculate the diffusive travel times associated with the startup of a gas production well. The inequality constraints are incorporated into the estimates of model parameter resolution and covariance, improving the resolution by roughly 30 to 40%.« less

Infiltration pattern in a regolith-fractured bedrock profile: field observation of a dye stain pattern

NASA Astrophysics Data System (ADS)

Kim, Jae Gon; Lee, Gyoo Ho; Lee, Jin-Soo; Chon, Chul-Min; Kim, Tack Hyun; Ha, Kyoochul

2006-02-01

We examined the infiltration pattern of water in a regolith-bedrock profile consisting of two overburdens (OB1 and OB2), a buried rice paddy soil (PS), two texturally distinctive weathered materials (WM1 and WM2) and a fractured sedimentary rock (BR), using a Brilliant Blue FCF dye tracer. A black-coloured coating in conducting fractures in WM1, WM2 and BR was analysed by X-ray diffraction and scanning electron microscopy. The dye tracer penetrated to greater than 2 m depth in the profile. The macropore flow and saturated interflow were the major infiltration patterns in the profile. Macropore flow and saturated interflow were observed along fractures in WM1, WM2 and BR and at the dipping interfaces of PS-WM1, PS-WM2 and PS-BR respectively. Heterogeneous matrix flow occurred in upper overburden (OB1) and PS. Compared with OB1, the coarser textured OB2 acted as a physical barrier for vertical flow of water. The PS with low bulk density and many fine roots was another major conducting route of water in the profile. Manganese oxide and iron oxide were positively identified in the black coating material and had low crystallinity and high surface area, indicating their high reactivity with conducting contaminants.

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

Narr, W.; Currie, J.B.

The occurrence of natural fracture systems in subsurface rock can be predicted if careful evaluation is made of the ecologic processes that affect sedimentary strata during their cycle of burial, diagenesis, uplift, and erosional unloading. Variations in the state of stress within rock arise, for example, from changes in temperature, pore pressure, weight of overburden, or tectonic loading. Hence geologic processes acting on a sedimentary unit should be analyzed for their several contributions to the state of stress, and this information used to compute a stress history. From this stress history, predictions may be made as to when in themore » burial cycle to expect fracture (joint) formation, what type of fractures (extension or shear) may occur, and which geologic factors are most favorable to development of fractures. A stress history is computed for strata of the naturally fractured Altamont oil field in Utah's Uinta basin. Calculations suggest that fractures formed in extension, that the well-cemented rocks are those most likely to be fractured, that fractures began to develop only after stata were uplifted and denuded of overburden. Geologic evidence on fracture genesis and development is in accord with the stress history prediction. Stress history can be useful in evaluating a sedimentary basin for naturally fractured reservoir exploration plays.« less

Earth Conductivity Estimation from Through-the-Earth Measurements of 94 Coal Mines Using Different Electromagnetic Models

PubMed Central

Yan, Lincan; Waynert, Joseph; Sunderman, Carl

2015-01-01

Through-the-Earth (TTE) communication systems require minimal infrastructure to operate. Hence, they are assumed to be more survivable and more conventional than other underground mine communications systems. This survivability is a major advantage for TTE systems. In 2006, Congress passed the Mine Improvement and New Emergency Response Act (MINER Act), which requires all underground coal mines to install wireless communications systems. The intent behind this mandate is for trapped miners to be able to communicate with surface personnel after a major accident-hence, the interest in TTE communications. To determine the likelihood of establishing a TTE communication link, it would be ideal to be able to predict the apparent conductivity of the overburden above underground mines. In this paper, all 94 mine TTE measurement data collected by Bureau of Mines in the 1970s and early 1980s, are analyzed for the first time to determine the apparent conductivity of the overburden based on three different models: a homogenous half-space model, a thin sheet model, and an attenuation factor or Q-factor model. A statistical formula is proposed to estimate the apparent earth conductivity for a specific mine based on the TTE modeling results given the mine depth and signal frequency. PMID:26213457

Mathematical modeling and measurement of electric fields of electrode-based through-the-earth (TTE) communication

NASA Astrophysics Data System (ADS)

Yan, Lincan; Zhou, Chenming; Reyes, Miguel; Whisner, Bruce; Damiano, Nicholas

2017-06-01

There are two types of through-the-earth (TTE) wireless communication in the mining industry: magnetic loop TTE and electrode-based (or linear) TTE. While the magnetic loop systems send signal through magnetic fields, the transmitter of an electrode-based TTE system sends signal directly through the mine overburden by driving an extremely low frequency (ELF) or ultralow frequency (ULF) AC current into the earth. The receiver at the other end (underground or surface) detects the resultant current and receives it as a voltage. A wireless communication link between surface and underground is then established. For electrode-based TTE communications, the signal is transmitted through the established electric field and is received as a voltage detected at the receiver. It is important to understand the electric field distribution within the mine overburden for the purpose of designing and improving the performance of the electrode-based TTE systems. In this paper, a complete explicit solution for all three electric field components for the electrode-based TTE communication was developed. An experiment was conducted using a prototype electrode-based TTE system developed by National Institute for Occupational Safety and Health. The mathematical model was then compared and validated with test data. A reasonable agreement was found between them.

Mathematical modeling and measurement of electric fields of electrode-based through-the-earth (TTE) communication.

PubMed

Yan, Lincan; Zhou, Chenming; Reyes, Miguel; Whisner, Bruce; Damiano, Nicholas

2017-07-12

There are two types of through-the-earth (TTE) wireless communication in the mining industry: magnetic loop TTE and electrode-based (or linear) TTE. While the magnetic loop systems send signal through magnetic fields, the transmitter of an electrode-based TTE system sends signal directly through the mine overburden by driving an extremely low frequency (ELF) or ultralow frequency (ULF) AC current into the earth. The receiver at the other end (underground or surface) detects the resultant current and receives it as a voltage. A wireless communication link between surface and underground is then established. For electrode-based TTE communications, the signal is transmitted through the established electric field and is received as a voltage detected at the receiver. It is important to understand the electric field distribution within the mine overburden for the purpose of designing and improving the performance of the electrode-based TTE systems. In this paper, a complete explicit solution for all three electric field components for the electrode-based TTE communication was developed. An experiment was conducted using a prototype electrode-based TTE system developed by National Institute for Occupational Safety and Health. The mathematical model was then compared and validated with test data. A reasonable agreement was found between them.

Earth Conductivity Estimation from Through-the-Earth Measurements of 94 Coal Mines Using Different Electromagnetic Models.

PubMed

Yan, Lincan; Waynert, Joseph; Sunderman, Carl

2014-10-01

Through-the-Earth (TTE) communication systems require minimal infrastructure to operate. Hence, they are assumed to be more survivable and more conventional than other underground mine communications systems. This survivability is a major advantage for TTE systems. In 2006, Congress passed the Mine Improvement and New Emergency Response Act (MINER Act), which requires all underground coal mines to install wireless communications systems. The intent behind this mandate is for trapped miners to be able to communicate with surface personnel after a major accident-hence, the interest in TTE communications. To determine the likelihood of establishing a TTE communication link, it would be ideal to be able to predict the apparent conductivity of the overburden above underground mines. In this paper, all 94 mine TTE measurement data collected by Bureau of Mines in the 1970s and early 1980s, are analyzed for the first time to determine the apparent conductivity of the overburden based on three different models: a homogenous half-space model, a thin sheet model, and an attenuation factor or Q-factor model. A statistical formula is proposed to estimate the apparent earth conductivity for a specific mine based on the TTE modeling results given the mine depth and signal frequency.

Mathematical modeling and measurement of electric fields of electrode-based through-the-earth (TTE) communication

PubMed Central

Yan, Lincan; Zhou, Chenming; Reyes, Miguel; Whisner, Bruce; Damiano, Nicholas

2017-01-01

There are two types of through-the-earth (TTE) wireless communication in the mining industry: magnetic loop TTE and electrode-based (or linear) TTE. While the magnetic loop systems send signal through magnetic fields, the transmitter of an electrode-based TTE system sends signal directly through the mine overburden by driving an extremely low frequency (ELF) or ultralow frequency (ULF) AC current into the earth. The receiver at the other end (underground or surface) detects the resultant current and receives it as a voltage. A wireless communication link between surface and underground is then established. For electrode-based TTE communications, the signal is transmitted through the established electric field and is received as a voltage detected at the receiver. It is important to understand the electric field distribution within the mine overburden for the purpose of designing and improving the performance of the electrode-based TTE systems. In this paper, a complete explicit solution for all three electric field components for the electrode-based TTE communication was developed. An experiment was conducted using a prototype electrode-based TTE system developed by National Institute for Occupational Safety and Health. The mathematical model was then compared and validated with test data. A reasonable agreement was found between them. PMID:28845062

Crater Formation Above Salt Caverns: Piston vs Hour-glass

NASA Astrophysics Data System (ADS)

Berest, P.

2016-12-01

Conditions leading to crater formation above salt caverns are discussed. In most cases, at the end of leaching, the cavern roof had reached the top of the salt formation, allowing direct contact between brine and marl (or argillite) layers that compose the overburden of the salt formation. These layers are prone to weathering when in contact with saturated brine. Stoping takes place, and the cavern roof rises through the overburden. This process may be several years or dozens of years long. In Lorraine salt formations, stoping stops when the rising cavern top reaches a competent layer, the Beaumont Dolomite. Operators then lower cavern-brine pressure to trigger collapse. A rigid cylinder of rock (a "piston") drops into the cavern, and a crater whose initial edges are vertical is created. Cavern drop is more abrupt when the cavern top is filled partly with air. The contour of the piston is circular, as a circle is the shape such that the ratio between perimeter and area is minimal. In other cases, for instance in Kansas, the cavern rises until the uppermost keystone in the bedrock at shallow depth is breached, permitting loose materials to flow into the cavern through a relatively narrow hole at the bottom of the sink hole, as in an hour glass.

Spatial Statistics of Deep-Water Ambient Noise; Dispersion Relations for Sound Waves and Shear Waves

DTIC Science & Technology

2014-09-30

marine sediments. New focus is on very fine- grained sediments (silt and clay ). OBJECTIVES 1) The scientific objective of the deep-water ambient...density, grain size and overburden pressure. A new focus is on the inter-particle cohesive forces in silts and clays and their role in controlling wave...algebraic expressions. The GS theory is the basis for new research on very fine-grained sediments (silts and clays ), in which inter-granular cohesion is

Centrifugal and Numerical Modeling of Buried Structures. Volume 2. Dynamic Soil-Structure Interaction.

DTIC Science & Technology

1987-07-14

RD-RISE 368 CENTRIFUGAL AND NUMERICAL MODELING OF BURIED STRUCTURES 1/3 VOLUME 2 DYNAMIC..(U) COLORADO UNIV AT BOULDER DEPT OF CIVIL ENVIRONMENTAL...20332-6448 ELEMENT NO NO. NO ACCESSION NO 61102F 2302 Cl 11 TITLE (Include Security Classification) (U) Centrifugal and Numerical Modeling of Buried ...were buried in a dry sand and tested in the centrifuge to simulate the effects of gravity-induced overburden stresses which played a major role in

Two generations at risk: child welfare, institutional boundaries, and family violence in grandparent homes.

PubMed

Day, Susan E; Bazemore, Gordon

2011-01-01

Participation of extended family members, particularly custodial grandparents, has generally resulted in better outcomes for abused children and relief for an overburdened child welfare system. This research explores the risk of adolescent perpetrated violence in custodial grandparent households with data from the Florida Department of Juvenile Justice. Findings suggest that living arrangements with custodial grandparents have a significant and differential impact on rates of violent offending for chronic and serious offenders by race and gender.

On the physics of frequency-domain controlled source electromagnetics in shallow water. 1: isotropic conductivity

NASA Astrophysics Data System (ADS)

Chave, Alan D.; Everett, Mark E.; Mattsson, Johan; Boon, James; Midgley, Jonathan

2017-02-01

In recent years, marine controlled source electromagnetics (CSEM) has found increasing use in hydrocarbon exploration due to its ability to detect thin resistive zones beneath the seafloor. It is the purpose of this paper to evaluate the physics of CSEM for an ocean whose electrical thickness is comparable to or much thinner than that of the overburden using the in-line configuration through examination of the elliptically polarized seafloor electric field, the time-averaged energy flow depicted by the real part of the complex Poynting vector, energy dissipation through Joule heating and the Fréchet derivatives of the seafloor field with respect to the subseafloor conductivity that is assumed to be isotropic. The deep water (ocean layer electrically much thicker than the overburden) seafloor EM response for a model containing a resistive reservoir layer has a greater amplitude and reduced phase as a function of offset compared to that for a half-space, or a stronger and faster response. For an ocean whose electrical thickness is comparable to or much smaller than that of the overburden, the electric field displays a greater amplitude and reduced phase at small offsets, shifting to a stronger amplitude and increased phase at intermediate offsets and a weaker amplitude and enhanced phase at long offsets, or a stronger and faster response that first changes to stronger and slower, and then transitions to weaker and slower. These transitions can be understood by visualizing the energy flow throughout the structure caused by the competing influences of the dipole source and guided energy flow in the reservoir layer, and the air interaction caused by coupling of the entire subseafloor resistivity structure with the sea surface. A stronger and faster response occurs when guided energy flow is dominant, while a weaker and slower response occurs when the air interaction is dominant. However, at intermediate offsets for some models, the air interaction can partially or

The stable isotopes of site wide waters at an oil sands mine in northern Alberta, Canada

NASA Astrophysics Data System (ADS)

Baer, Thomas; Barbour, S. Lee; Gibson, John J.

2016-10-01

Oil sands mines have large disturbance footprints and contain a range of new landforms constructed from mine waste such as shale overburden and the byproducts of bitumen extraction such as sand and fluid fine tailings. Each of these landforms are a potential source of water and chemical release to adjacent surface and groundwater, and consequently, the development of methods to track water migration through these landforms is of importance. The stable isotopes of water (i.e. 2H and 18O) have been widely used in hydrology and hydrogeology to characterize surface water/groundwater interactions but have not been extensively applied in mining applications, or specifically to oil sands mining in northern Alberta. A prerequisite for applying these techniques is the establishment of a Local Meteoric Water Line (LMWL) to characterize precipitation at the mine sites as well as the development of a 'catalogue' of the stable water isotope signatures of various mine site waters. This study was undertaken at the Mildred Lake Mine Site, owned and operated by Syncrude Canada Ltd. The LMWL developed from 2 years (2009/2012) of sample collection is shown to be consistent with other LMWLs in western Canada. The results of the study highlight the unique stable water isotope signatures associated with hydraulically placed tailings (sand or fluid fine tailings) and overburden shale dumps relative to natural surface water and groundwater. The signature associated with the snow melt water on reclaimed landscapes was found to be similar to ground water recharge in the region. The isotopic composition of the shale overburden deposits are also distinct and consistent with observations made by other researchers in western Canada on undisturbed shales. The process water associated with the fine and coarse tailings streams has highly enriched 2H and 18O signatures. These signatures are developed through the non-equilibrium fractionation of imported fresh river water during evaporation from

Liquefaction assessment based on combined use of CPT and shear wave velocity measurements

NASA Astrophysics Data System (ADS)

Bán, Zoltán; Mahler, András; Győri, Erzsébet

2017-04-01

Soil liquefaction is one of the most devastating secondary effects of earthquakes and can cause significant damage in built infrastructure. For this reason liquefaction hazard shall be considered in all regions where moderate-to-high seismic activity encounters with saturated, loose, granular soil deposits. Several approaches exist to take into account this hazard, from which the in-situ test based empirical methods are the most commonly used in practice. These methods are generally based on the results of CPT, SPT or shear wave velocity measurements. In more complex or high risk projects CPT and VS measurement are often performed at the same location commonly in the form of seismic CPT. Furthermore, VS profile determined by surface wave methods can also supplement the standard CPT measurement. However, combined use of both in-situ indices in one single empirical method is limited. For this reason, the goal of this research was to develop such an empirical method within the framework of simplified empirical procedures where the results of CPT and VS measurements are used in parallel and can supplement each other. The combination of two in-situ indices, a small strain property measurement with a large strain measurement, can reduce uncertainty of empirical methods. In the first step by careful reviewing of the already existing liquefaction case history databases, sites were selected where the records of both CPT and VS measurement are available. After implementing the necessary corrections on the gathered 98 case histories with respect to fines content, overburden pressure and magnitude, a logistic regression was performed to obtain the probability contours of liquefaction occurrence. Logistic regression is often used to explore the relationship between a binary response and a set of explanatory variables. The occurrence or absence of liquefaction can be considered as binary outcome and the equivalent clean sand value of normalized overburden corrected cone tip

Gravitational salt tectonics above a rising basement plateau offshore Algeria

NASA Astrophysics Data System (ADS)

Gaullier, Virginie; Vendeville, Bruno C.; Besème, Grégoire; Legoux, Gaetan; Déverchère, Jacques; Lymer, Gaël

2017-04-01

Seismic data (survey "MARADJA 1", 2003) offshore the Algerian coast have imaged an unexpected deformation pattern of the Messinian salt (Mobile Unit; MU) and its sedimentary overburden (Messinian Upper Unit and Plio-Quaternary) above an actively rising plateau in the subsalt basement. From a geodynamic point of view, the region is undergoing crustal convergence, as attested by the Boumerdes earthquake (2003, magnitude 6.8). The rise of this plateau, forming a 3D promontory restricted to the area offshore Algiers, is associated with that geodynamic setting. The seismic profiles show several subsalt thrusts (Domzig et al. 2006). The data provided additional information on the deformation of the Messinian mobile evaporitic unit and its Plio-Quaternary overburden. Margin-perpendicular profiles show mostly compressional features (anticlines and synclines) that had little activity during Messinian times, then grew more during Plio-Quaternary times. A few normal faults are also present, but are not accompanied by salt rise. By contrast, margin-parallel profiles clearly show that extensional, reactive salt diapiric ridges (symptomatic with their triangular shape in cross section) formed early, as early as the time of deposition of the Messinian Upper Unit, as recorded by fan-shaped strata. These ridges have recorded E-W, thin-skinned gravity gliding above the Messinian salt, as a response to the rise of the basement plateau. We tested this hypothesis using two analogue models, one where we assumed that the rise of the plateau started after Messinian times (initially tabular salt across the entire region), the second model assumed that the plateau had already risen partially as the Messininan Mobile Unit was deposited (salt initially thinner above the plateau than in the adjacent regions). In both experiments, the rise of the plateau generated preferential E-W extension above the salt, combined with N-S shortening. Extension was caused by gravity gliding of the salt from

The Influence of Impurities and Metallic Capping Layers on the Microstructure of Copper Interconnects

NASA Astrophysics Data System (ADS)

Rizzolo, Michael

As copper interconnects have scaled to ever smaller dimensions on semiconductor devices, the microstructure has become increasingly detrimental for performance and reliability. Small grains persist in interconnects despite annealing at high temperatures, leading to higher line resistance and more frequent electromigration-induced failures. Conventionally, it was believed that impurities from the electrodeposition pinned grain growth, but limitations in analytical techniques meant the effect was inferred rather than observed. Recent advances in analytical techniques, however, have enabled this work to quantify impurity content, location, and diffusion in relation to microstructural changes in electroplated copper. Surface segregation of impurities during the initial burst of grain growth was investigated. After no surface segregation was observed, a microfluidic plating cell was constructed to plate multilayer films with regions of intentionally high and low impurity concentrations to determine if grain growth could be pinned by the presence of impurities; it was not. An alternate mechanism for grain boundary pinning based on the texture of the seed layer is proposed, supported by time-resolved transmission electron microscopy and transmission electron backscatter diffraction data. The suggested model posits that the seed in narrow features has no preferred orientation, which results in rapid nucleation of subsurface grains in trench regions prior to recrystallization from the overburden down. These rapidly growing grains are able to block off several trenches from the larger overburden grains, inhibiting grain growth in narrow features. With this knowledge in hand, metallic capping layers were employed to address the problematic microstructure in 70nm lines. The capping layers (chromium, nickel, zinc, and tin) were plated on the copper overburden prior to annealing to manipulate the stress gradient and microstructural development during annealing. It appeared that

Experimental and Numerical Investigation on the Bearing and Failure Mechanism of Multiple Pillars Under Overburden

NASA Astrophysics Data System (ADS)

Zhou, Zilong; Chen, Lu; Zhao, Yuan; Zhao, Tongbin; Cai, Xin; Du, Xueming

2017-04-01

To reveal the mechanical response of a multi-pillar supporting system under external loads, compressive tests were carried out on single-pillar and double-pillar specimens. The digital speckle correlation method and acoustic emission technique were applied to record and analyse information of the deformation and failure processes. Numerical simulations with the software programme PFC2D were also conducted. In the compressive process of the double-pillar system, if both individual pillars have the same mechanical properties, each pillar deforms similarly and reaches the critical stable state almost simultaneously by sharing equal loads. If the two individual pillars have different mechanical properties, the pillar with higher elastic modulus or lower strength would be damaged and lose its bearing capacity firstly. The load would then be transferred to the other pillar under a load redistribution process. When the pillar with higher strength is strong enough, the load carried by the pillar system would increase again. However, the maximum bearing load of the double-pillar system is smaller than the sum of peak load of individual pillars. The study also indicates that the strength, elastic modulus, and load state of pillars all influence the supporting capacity of the pillar system. In underground space engineering, the appropriate choice of pillar dimensions and layout may play a great role in preventing the occurrence of cascading pillar failure.

W.E.E.D.--Writing Essays Every Day (A Guide for the Overburdened English Teacher).

ERIC Educational Resources Information Center

Mitchell, Ken

1986-01-01

Describes the WEED program, in which students write every day but not all papers receive a teacher evaluation. Discusses getting started, follow-up, collecting papers and grading, incentives, and the results of the program. (EL)

The Experience of Implementation of Innovative Technology of Quarry Waste Water Purifying in Kuzbass Open Pit

NASA Astrophysics Data System (ADS)

Lesin, Yu V.; Hellmer, M. C.

2016-08-01

Among all industries in Kuzbass (Western Siberia, Russia) the coal industry provides the most environmental threat. However, the construction of new and maintenance of existing open pit mines do not often correspond to the tasks of improving the environmental safety of surface mining. So the article describes the use of innovative quarry waste water purifying technology implemented in Kuzbass open pit mine «Shestaki». This technology is based on using artificial filter arrays made of overburden rock.

Sunbelt strives for diversification

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

Jackson, D.

1982-08-01

The Sunbelt Mining Co. is a subsidiary of the Public Service Co., of New Mexico which seeks out and develops additional resources for both its parent company and new customers. The De-Na-Zin surface mine in the Bisti coalfield of New Mexico is described, together with the aggregate crushing and screening facility that supplies road construction material to the mine. The problem of overburden removal and the reclamation of land in the desert is discussed.

Implementation of Process Management for a Secure Archival Storage System.

DTIC Science & Technology

1981-03-01

SE9CURITY CLASSIFICATION OF ’TweS PA4Men~ Des Sweead REPORT DOCUMTATION PAGE SWIM& DISTRCTINORM 0. RPORT MU111 12. GOVT ACCISSIN NO . RmCIPICNT’S CATAL.Oo...8217r I ’ , ! .... .. - - Coleman [3] are available as a sinale publication from NTIS and DDC in a report prepared by Schell and Cox (211. Further...on their customers. Universities and scientific institutions must prevent the unauthorized use of their often over-burdened systems. The Department of

Initiation and growth of gypsum piercement structures in the Zechstein Basin

USGS Publications Warehouse

Williams-Stroud, S. C.; Paul, J.

1997-01-01

The importance of tectonic processes in initiating halite diapirs has become much better understood in recent years. Less well understood is the development of diapiric structures involving rocks composed predominantly of gypsum. Below about 1000 m, gypsum dehydrates to anhydrite, which often obscures primary sedimentary textures. If the strain associated with diapiric rise in the rock induces the transition to anhydrite, obliteration of primary features in the gypsum can be expected. In our study, we infer that the diapiric movement in the Werra Anhydrite member of cycle 1 of the Zechstein Formation of Europe occurred before the initial transition of gypsum to anhydrite based on the presence of pseudomorphs of bedded primary gypsum crystals, the overburden lithologies and depositional environment, and the mechanical properties of gypsum, anhydrite and carbonate rocks. Faulting and differential loading of a shallow overburden were the key components in initiating the gypsum diapirism. The transition to anhydrite occurred after burial and after cessation of diapirism. In comparison, the diapirism of calcium sulfate of the Leine Anhydrite into the Leine Halite members of cycle 3 of the Zechstein Formation probably occurred much later after burial and appears to have been triggered by halite diapirism, which in turn triggered the dehydration reaction, causing the calcium sulfate to become the incompetent phase relative to the halite. Published by Elsevier Science Ltd.

Geology, coal resources, and chemical analyses of coal from the Fruitland Formation, Kimbeto EMRIA study site, San Juan County, New Mexico

USGS Publications Warehouse

Schneider, Gary B.; Hildebrand, Rick T.; Affolter, Ronald H.

1979-01-01

The Kimbeto EMRIA study site, an area of about 20 square miles (52 km2), is located on the south margin of the San Juan Basin on the gently northward-dipping strata of the Upper Cretaceous Fruitland Formation and the Kirtland Shale. The coal beds are mainly in the lower 150 feet (45 m) of the Fruitland Format ion. Coal resources--measured, indicated, and inferred--with less than 400 feet (120 m) of overburden in the site are 69,085,000 short tons (62,660,100 metric tons), 369,078,000 short tons (334,754,000 metric tons), and 177,803,000 short tons (161,267,000 metric tons) respectively. About 68 percent of these resources are overlain by 200 feet (60 m) or less of overburden. The apparent rank of the coal ranges from subbituminous B to subbituminous A. The average Btu/lb value of 14 core samples from the site on the as-received basis is 8,240 (4580 Kcal/kg), average ash content is 23.4 percent, and average sulfur content is 0.5 percent. Analyses of coal from the Kimbeto EMRIA study site show significantly higher ash content and significantly lower contents of volatile matter, fixed carbon, carbon, and a significantly lower heat of combustion when compared with other coal analyses from the Rocky Mountain province.

Measurements of the Reactor Antineutrino with Solid State Scintillation Detector

NASA Astrophysics Data System (ADS)

Alekseev, I.; Belov, V.; Brudanin, V.; Danilov, M.; Egorov, V.; Filosofov, D.; Fomina, M.; Hons, Z.; Kazartsev, S.; Kobyakin, A.; Kuznetsov, A.; Machikhiliyan, I.; Medvedev, D.; Nesterov, V.; Olshevsky, A.; Pogorelov, N.; Ponomarev, D.; Rozova, I.; Rumyantseva, N.; Rusinov, V.; Salamatin, A.; Samigullin, E.; Shevchik, Ye.; Shirchenko, M.; Shitov, Yu.; Skrobova, N.; Starostin, A.; Svirida, D.; Tarkovsky, E.; Tikhomirov, I.; Vlášek, J.; Zhitnikov, I.; Zinatulina, D.

Measurements of reactor antineutrino play an important role in the efforts at the frontier of the modern physics. The DANSS collaboration presents preliminary results of a one year run with a cubic meter solid state detector placed below 3.1 GW industrial light water reactor. The experiment is sensitive to sterile neutrino in the most interesting region of mixing parameter space. 2500 scintillation strips of the sensitive volume of the detector have multilayer passive shielding of copper, lead and borated polyethylene and active muon veto. Detector position below the reactor gives an advantage of overburden about 50 m of water equivalent providing factor of six in cosmic muon suppression and eliminating fast neutrons.The detector is placed on a vertically movable platform which allows to change the distance to the reactor core center in the range 10.7-12.7 m within a few minutes. The strips are read out individually by SiPMs and in groups of 50 by PMTs. 5000 inverse beta-decay events per day are collected in the fiducial volume, which is 78% of the whole detector, at the position closest to the reactor. Overburden, active veto and good segmentation of the detector result in an excellent signal to background ratio. The talk is dedicated to the data analysis and preliminary results. The experiment status is also presented.

Black Thunder Coal Mine and Los Alamos National Laboratory experimental study of seismic energy generated by large scale mine blasting

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

Martin, R.L.; Gross, D.; Pearson, D.C.

In an attempt to better understand the impact that large mining shots will have on verifying compliance with the international, worldwide, Comprehensive Test Ban Treaty (CTBT, no nuclear explosion tests), a series of seismic and videographic experiments has been conducted during the past two years at the Black Thunder Coal Mine. Personnel from the mine and Los Alamos National Laboratory have cooperated closely to design and perform experiments to produce results with mutual benefit to both organizations. This paper summarizes the activities, highlighting the unique results of each. Topics which were covered in these experiments include: (1) synthesis of seismic,more » videographic, acoustic, and computer modeling data to improve understanding of shot performance and phenomenology; (2) development of computer generated visualizations of observed blasting techniques; (3) documentation of azimuthal variations in radiation of seismic energy from overburden casting shots; (4) identification of, as yet unexplained, out of sequence, simultaneous detonation in some shots using seismic and videographic techniques; (5) comparison of local (0.1 to 15 kilometer range) and regional (100 to 2,000 kilometer range) seismic measurements leading to determine of the relationship between local and regional seismic amplitude to explosive yield for overburden cast, coal bulking and single fired explosions; and (6) determination of the types of mining shots triggering the prototype International Monitoring System for the CTBT.« less

A multiscale fixed stress split iterative scheme for coupled flow and poromechanics in deep subsurface reservoirs

NASA Astrophysics Data System (ADS)

Dana, Saumik; Ganis, Benjamin; Wheeler, Mary F.

2018-01-01

In coupled flow and poromechanics phenomena representing hydrocarbon production or CO2 sequestration in deep subsurface reservoirs, the spatial domain in which fluid flow occurs is usually much smaller than the spatial domain over which significant deformation occurs. The typical approach is to either impose an overburden pressure directly on the reservoir thus treating it as a coupled problem domain or to model flow on a huge domain with zero permeability cells to mimic the no flow boundary condition on the interface of the reservoir and the surrounding rock. The former approach precludes a study of land subsidence or uplift and further does not mimic the true effect of the overburden on stress sensitive reservoirs whereas the latter approach has huge computational costs. In order to address these challenges, we augment the fixed-stress split iterative scheme with upscaling and downscaling operators to enable modeling flow and mechanics on overlapping nonmatching hexahedral grids. Flow is solved on a finer mesh using a multipoint flux mixed finite element method and mechanics is solved on a coarse mesh using a conforming Galerkin method. The multiscale operators are constructed using a procedure that involves singular value decompositions, a surface intersections algorithm and Delaunay triangulations. We numerically demonstrate the convergence of the augmented scheme using the classical Mandel's problem solution.

Evaluation of subsidence hazard in mantled karst setting: a case study from Val d'Orléans (France)

NASA Astrophysics Data System (ADS)

Perrin, Jérôme; Cartannaz, Charles; Noury, Gildas; Vanoudheusden, Emilie

2015-04-01

Soil subsidence/collapse is a major geohazard occurring in karst region. It occurs as suffosion or dropout sinkholes developing in the soft cover. Less frequently it corresponds to a breakdown of karst void ceiling (i.e., collapse sinkhole). This hazard can cause significant engineering challenges. Therefore decision-makers require the elaboration of methodologies for reliable predictions of such hazards (e.g., karst subsidence susceptibility and hazards maps, early-warning monitoring systems). A methodological framework was developed to evaluate relevant conditioning factors favouring subsidence (Perrin et al. submitted) and then to combine these factors to produce karst subsidence susceptibility maps. This approach was applied to a mantled karst area south of Paris (Val d'Orléans). Results show the significant roles of the overburden lithology (presence/absence of low-permeability layer) and of the karst aquifer piezometric surface position within the overburden. In parallel, an experimental site has been setup to improve the understanding of key processes leading to subsidence/collapse and includes piezometers for measurements of water levels and physico-chemical parameters in both the alluvial and karst aquifers as well as surface deformation monitoring. Results should help in designing monitoring systems to anticipate occurrence of subsidence/collapse. Perrin J., Cartannaz C., Noury G., Vanoudheusden E. 2015. A multicriteria approach to karst subsidence hazard mapping supported by Weights-of-Evidence analysis. Submitted to Engineering Geology.

24th International Symposium on Ballistics

DTIC Science & Technology

2008-09-26

production Samples dimensions were 0.3x0.05 m. Test set up Gas gun 5.5 mm diameter steel spheres and sabot Velocity measuring  systems High speed rate...Oilwell perforators – small caliber shaped charges – create the pathway for oil or gas to flow from the reservoir rock into the wellbore  Deep, clean ...overburden, tectonic) – Pore fluid pressure – Pore fluid type ( liquid vs. gas ) Background  Geomechanics considerations: – In-situ stresses (“total

The research of collapsibility test and FEA of collapse deformation in loess collapsible under overburden pressure

NASA Astrophysics Data System (ADS)

yu, Zhang; hui, Li; guibo, Bao; wuyu, Zhang; ningshan, Jiang; xiaoyun, Yang

2018-05-01

The collapsibility test in field may have huge error with computed results[1-4]. The writer gave a compare between single-line and double-line method and then compared with the field’s result. The writer’s purpose is to reduce the error of measured value to computed value and propose a way to decrease the error through consider the matric suction’s influence to unsaturated soil in using finite element analysis, field test was completed to verify the reasonability of this method and get some regulate of development of collapse deformation and supply some calculation basis of engineering design and forecast in emergency situation.

Calculation of Tectonic Strain Release from an Explosion in a Three-Dimensional Stress Field

NASA Astrophysics Data System (ADS)

Stevens, J. L.; O'Brien, M. S.

2012-12-01

We have developed a 3D nonlinear finite element code designed for calculation of explosions in 3D heterogeneous media and have incorporated the capability to perform explosion calculations in a prestressed medium. The effect of tectonic prestress on explosion-generated surface waves has been discussed since the 1960's. In most of these studies tectonic release was described as superposition of a tectonic source modeled as a double couple, multipole or moment tensor, plus a point explosion source. The size of the tectonic source was determined by comparison with the observed Love waves and the Rayleigh wave radiation pattern. Day et al. (1987) first attempted to perform numerical modeling of tectonic release through an axisymmetric calculation of the explosion Piledriver. To the best of our knowledge no one has previously performed numerical calculations for an explosion in a three-dimensional stress field. Calculation of tectonic release depends on a realistic representation of the stress state in the earth. In general the vertical stress is equal to the overburden weight of the material above at any given point. The horizontal stresses may be larger or smaller than this value up to the point where failure due to frictional sliding relieves the stress. In our calculations, we use the normal overburden calculation to determine the vertical stress, and then modify the horizontal stresses to some fraction of the frictional limit. This is the initial stable state of the calculation prior to introduction of the explosion. Note that although the vertical stress is still equivalent to the overburden weight, the pressure is not, and it may be either increased or reduced by the tectonic stresses. Since material strength increases with pressure, this also can substantially affect the seismic source. In general, normal faulting regimes will amplify seismic signals, while reverse faulting regimes will decrease seismic signals; strike-slip regimes may do either. We performed a

Kinematics and dynamics of salt movement driven by sub-salt normal faulting and supra-salt sediment accumulation - combined analogue experiments and analytical calculations

NASA Astrophysics Data System (ADS)

Warsitzka, Michael; Kukowski, Nina; Kley, Jonas

2017-04-01

In extensional sedimentary basins, the movement of ductile salt is mainly controlled by the vertical displacement of the salt layer, differential loading due to syn-kinematic deposition, and tectonic shearing at the top and the base of the salt layer. During basement normal faulting, salt either tends to flow downward to the basin centre driven by its own weight or it is squeezed upward due to differential loading. In analogue experiments and analytical models, we address the interplay between normal faulting of the sub-salt basement, compaction and density inversion of the supra-salt cover and the kinematic response of the ductile salt layer. The analogue experiments consist of a ductile substratum (silicone putty) beneath a denser cover layer (sand mixture). Both layers are displaced by normal faults mimicked through a downward moving block within the rigid base of the experimental apparatus and the resulting flow patterns in the ductile layer are monitored and analysed. In the computational models using an analytical approximative solution of the Navier-Stokes equation, the steady-state flow velocity in an idealized natural salt layer is calculated in order to evaluate how flow patterns observed in the analogue experiments can be translated to nature. The analytical calculations provide estimations of the prevailing direction and velocity of salt flow above a sub-salt normal fault. The results of both modelling approaches show that under most geological conditions salt moves downwards to the hanging wall side as long as vertical offset and compaction of the cover layer are small. As soon as an effective average density of the cover is exceeded, the direction of the flow velocity reverses and the viscous material is squeezed towards the elevated footwall side. The analytical models reveal that upward flow occurs even if the average density of the overburden does not exceed the density of salt. By testing various scenarios with different layer thicknesses

Geophysical investigations of well fields to characterize fractured-bedrock aquifers in southern New Hampshire

USGS Publications Warehouse

Degnan, James R.; Moore, Richard Bridge; Mack, Thomas J.

2001-01-01

Bedrock-fracture zones near high-yield bedrock wells in southern New Hampshire well fields were located and characterized using seven surface and six borehole geophysical survey methods. Detailed surveys of six sites with various methods provide an opportunity to integrate and compare survey results. Borehole geophysical surveys were conducted at three of the sites to confirm subsurface features. Hydrogeologic settings, including a variety of bedrock and surface geologic materials, were sought to gain an insight into the usefulness of the methods in varied terrains. Results from 15 survey lines, 8 arrays, and 3 boreholes were processed and interpreted from the 6 sites. The surface geophysical methods used provided physical properties of fractured bedrock. Seismic refraction and ground-penetrating radar (GPR) primarily were used to characterize the overburden materials, but in a few cases indicated bedrock-fracture zones. Magnetometer surveys were used to obtain background information about the bedrock to compare with other results, and to search for magnetic lows, which may result from weathered fractured rock. Electromagnetic terrain conductivity surveys (EM) and very-low-frequency electromagnetic surveys (VLF) were used as rapid reconnaissance techniques with the primary purpose of identifying electrical anomalies, indicating potential fracture zones in bedrock. Direct-current (dc) resistivity methods were used to gather detailed subsurface information about fracture depth and orientation. Two-dimensional (2-D) dc-resistivity surveys using dipole-dipole and Schlumberger arrays located and characterized the overburden, bedrock, and bedrock-fracture zones through analysis of data inversions. Azimuthal square array dc-resistivity survey results indicated orientations of conductive steep-dipping bedrock-fracture zones that were located and characterized by previously applied geophysical methods. Various available data sets were used for site selection

A Comparative Analysis of the Influence of Surface Mining on Hydrological and Geochemical Response of Selected Headwater Streams in the Elk Valley, British Columbia, Canada.

NASA Astrophysics Data System (ADS)

Carey, S. K.; Shatilla, N. J.; Szmudrowska, B.; Rastelli, J.; Wellen, C.

2014-12-01

Surface mining is a common method of accessing coal. Blasting of overburden rock allows access to mineable ore. In high-elevation environments, the removed overburden rock is deposited in adjacent valleys as waste rock spoils. As part of a multi-year R&D program examining the influence of surface mining on watershed hydrological and water quality responses in the Elk Valley, British Columbia, this study reports on how surface mining affects streamflow hydrological and geochemical response at four reference and four mine-influenced catchments. The hydrology of this environment is dominated by snowmelt and steep topographic gradients. Flows were attenuated in mine-influenced catchments, with spring freshet delayed and more muted responses to precipitation events observed. Dissolved ions were an order of magnitude greater in mine-influenced streams, with more dilution-based responses to flows compared with chemostatic behavior observed in reference streams. Stable isotope signatures in stream water suggested that in both mine-influenced and reference watersheds, stream water was derived from well mixed groundwater as annual variability of stream isotope signatures was dampened compared with precipitation signatures. However, deflection of stream isotopes in response to precipitation were more apparent in reference watersheds. As a group, mine influenced catchments had a heavier isotope signature than reference watersheds, suggesting an enhanced influence of rainfall on recharge. Transit time distributions indicate existing waste rock spoils increase the average time water takes to move through the catchment.

Imaging a vertical shaft from a tunnel using muons

NASA Astrophysics Data System (ADS)

Bonal, N.; Preston, L. A.; Dorsey, D. J.; Schwellenbach, D.; Green, A.; Smalley, D.

2015-12-01

We use muon technology to image a vertical shaft from a tunnel. The density of the materials through which cosmic ray muons pass influences the flux of muons because muons are more attenuated by higher density material. Additionally, muons can travel several kilometers allowing measurements through deep rock. Density maps are generated from muon flux measurements to locate subsurface features like tunnel structures and ore bodies. Additionally, muon data can be jointly inverted with other data such as gravity and seismic to produce higher quality earth models than produced from a single method. We collected several weeks of data in a tunnel to image a vertical shaft. The minimum length of rock between the vertical shaft and the detector is 120 meters and the diameter of the vertical shaft is 4.6 meters. The rock the muons traveled through consists of Tertiary age volcanic tuff and steeply dipping, small-displacement faults. Results will be presented for muon flux in the tunnel and Monte-Carlo simulations of this experiment. Simulations from both GEANT4 (Geometry And Tracking version 4) and MCNP6 (Monte-Carlo N-Particle version 6) models will be compared. The tunnel overburden from muon measurements is also estimated and compared with actual the overburden. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

An empirical method to estimate shear wave velocity of soils in the New Madrid seismic zone

USGS Publications Warehouse

Wei, B.-Z.; Pezeshk, S.; Chang, T.-S.; Hall, K.H.; Liu, Huaibao P.

1996-01-01

In this study, a set of charts are developed to estimate shear wave velocity of soils in the New Madrid seismic zone (NMSZ), using the standard penetration test (SPT) N values and soil depths. Laboratory dynamic test results of soil samples collected from the NMSZ showed that the shear wave velocity of soils is related to the void ratio and the effective confining pressure applied to the soils. The void ratio of soils can be estimated from the SPT N values and the effective confining pressure depends on the depth of soils. Therefore, the shear wave velocity of soils can be estimated from the SPT N value and the soil depth. To make the methodology practical, two corrections should be made. One is that field SPT N values of soils must be adjusted to an unified SPT N??? value to account the effects of overburden pressure and equipment. The second is that the effect of water table to effective overburden pressure of soils must be considered. To verify the methodology, shear wave velocities of five sites in the NMSZ are estimated and compared with those obtained from field measurements. The comparison shows that our approach and the field tests are consistent with an error of less than of 15%. Thus, the method developed in this study is useful for dynamic study and practical designs in the NMSZ region. Copyright ?? 1996 Elsevier Science Limited.

Three-dimensional joint inversion for magnetotelluric resistivity and static shift distributions in complex media

NASA Astrophysics Data System (ADS)

Sasaki, Yutaka; Meju, Max A.

2006-05-01

Accurate interpretation of magnetotelluric (MT) data in the presence of static shift arising from near-surface inhomogeneities is an unresolved problem in three-dimensional (3-D) inversion. While it is well known in 1-D and 2-D studies that static shift can lead to erroneous interpretation, how static shift can influence the result of 3-D inversion is not fully understood and is relevant to improved subsurface analysis. Using the synthetic data generated from 3-D models with randomly distributed heterogeneous overburden and elongate homogeneous overburden that are consistent with geological observations, this paper examines the effects of near-surface inhomogeneity on the accuracy of 3-D inversion models. It is found that small-scale and shallow depth structures are severely distorted while the large-scale structure is marginally distorted in 3-D inversion not accounting for static shift; thus the erroneous near-surface structure does degrade the reconstruction of smaller-scale structure at any depth. However, 3-D joint inversion for resistivity and static shift significantly reduces the artifacts caused by static shifts and improves the overall resolution, irrespective of whether a zero-sum or Gaussian distribution of static shifts is assumed. The 3-D joint inversion approach works equally well for situations where the shallow bodies are of small size or long enough to allow some induction such that the effects of near-surface inhomogeneity are manifested as a frequency-dependent shift rather than a constant shift.

Assessment of Blasting Performance Using Electronic Vis-à-Vis Shock Tube Detonators in Strong Garnet Biotite Sillimanite Gneiss Formations

NASA Astrophysics Data System (ADS)

Sharma, Suresh Kumar; Rai, Piyush

2016-04-01

This paper presents a comparative investigation of the shock tube and electronic detonating systems practised in bench blasting. The blast trials were conducted on overburden rocks of Garnet Biotite Sillimanite Gneiss formations in one of the largest metalliferous mine of India. The study revealed that the choice of detonating system was crucial in deciding the fragment size and its distribution within the blasted muck-piles. The fragment size and its distribution affected the digging rate of excavators. Also, the shape of the blasted muck-pile was found to be related to the degree of fragmentation. From the present work, it may be inferred that in electronic detonation system, timely release of explosive energy resulted in better overall blasting performance. Hence, the precision in delay time must be considered in designing blast rounds in such overburden rock formations. State-of-art image analysis, GPS based muck-pile profile plotting techniques were rigorously used in the investigation. The study revealed that a mean fragment size (K50) value for shock tube detonated blasts (0.55-0.59 m) was higher than that of electronically detonated blasts (0.43-0.45 m). The digging rate of designated shovels (34 m3) with electronically detonated blasts was consistently more than 5000 t/h, which was almost 13 % higher in comparison to shock tube detonated blasts. Furthermore, favourable muck-pile shapes were witnessed in electronically detonated blasts from the observations made on the dozer performance.

Assessment of groundwater vulnerability to leachate infiltration using electrical resistivity method

NASA Astrophysics Data System (ADS)

Mosuro, G. O.; Omosanya, K. O.; Bayewu, O. O.; Oloruntola, M. O.; Laniyan, T. A.; Atobi, O.; Okubena, M.; Popoola, E.; Adekoya, F.

2017-09-01

This aim of this work is to assess the degree of leachate infiltration at a dumpsite in Agbara industrial estate, Southwestern Nigeria using electrical resistivity techniques. Around the dumpsite were 45 vertical electrical sounding (VES) stations and 3 electrical resistivity tomography profiles. Current electrode spread varied from 300 to 600 m for the electrical sounding. Electrode configuration includes Schlumberger and Wenner array for sounding and profiling. The state of leachate contamination was tested using parameters such as aquifer vulnerability index, overburden protective capacity and longitudinal unit conductance (S i) derived from the apparent resistivity values. Four principal geoelectric layers inferred from the VES data include the topsoil, sand, clayey sand, and clay/shale. Resistivity values for these layers vary from 3 to 1688, 203 to 3642 123 to 388, and 67 to 2201 Ω m with corresponding thickness of 0.8-2.4, 2.5-140, 3-26 m and infinity, respectively. The leachate plume occurs at a maximum depth of 10 m on the 2-D inverse models of real electrical resistivity with an average depth of infiltration being 6 m in the study area. The correlation between longitudinal conductance and overburden protective capacity show that aquifers around the dumpsite have poor protective capacity and are vulnerable to leachate contamination. Leachate infiltration is favored by the absence of lithological barriers such as clay which in the study area are either mixed with sand or positioned away from the aquifer.

Synthetic resistivity calculations for the canonical depth-to-bedrock problem: A critical examination of the thin interbed problem and electrical equivalence theories

NASA Astrophysics Data System (ADS)

Weiss, C. J.; Knight, R.

2009-05-01

One of the key factors in the sensible inference of subsurface geologic properties from both field and laboratory experiments is the ability to quantify the linkages between the inherently fine-scale structures, such as bedding planes and fracture sets, and their macroscopic expression through geophysical interrogation. Central to this idea is the concept of a "minimal sampling volume" over which a given geophysical method responds to an effective medium property whose value is dictated by the geometry and distribution of sub- volume heterogeneities as well as the experiment design. In this contribution we explore the concept of effective resistivity volumes for the canonical depth-to-bedrock problem subject to industry-standard DC resistivity survey designs. Four models representing a sedimentary overburden and flat bedrock interface were analyzed through numerical experiments of six different resistivity arrays. In each of the four models, the sedimentary overburden consists of a thinly interbedded resistive and conductive laminations, with equivalent volume-averaged resistivity but differing lamination thickness, geometry, and layering sequence. The numerical experiments show striking differences in the apparent resistivity pseudo-sections which belie the volume-averaged equivalence of the models. These models constitute the synthetic data set offered for inversion in this Back to Basics Resistivity Modeling session and offer the promise to further our understanding of how the sampling volume, as affected by survey design, can be constrained by joint-array inversion of resistivity data.

Initiation of diapirism by regional extension

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

Jackson, M.P.A.; Vendeville, B.C.

Initiation of diapirism is one of the least understood aspects of salt tectonics. Sedimentary differential loading is a favorite explanation, but special conditions such as focused sedimentation are needed to trigger diapirism by differential loading. Compilation of published data from 18 of the world's salt-diapir provinces shows that salt upwelling is consistently linked in time with regional extension, whether thin-skinned or thick-skinned. Extended salt basins typically develop salt structures, whereas nonextended basins typically do not. In some basins containing thick salt (SW Iran), diapirism was delayed as long as 400 Ma until the basin was regionally extended. In other saltmore » provinces (Maritime Alps), episodic growth of salt diapirs correlates with episodic regional extension during opening of the Neo-Tethys and Atlantic Oceans. Once initiated, salt diapirism can continue after regional extension is succeeded by contraction or quiescence. Thus even in salt basins overprinted by inversion or orogenic contraction (Morocco, Lusitania, Basque-Cantabrian, North Sea), the diapirs were initiated during extension on divergent continental margins or in intracontinental rifts. This observed temporal link between extension and diapirism is consistent with physical and numerical modeling, which demonstrates that extensional faulting of the overburden directly causes diapirism whether the salt was deposited before, during, or after rifting. Where the overburden is thinned by extension, pressurized salt wells up in response to the shifting positions of fault blocks.« less

Physical conditions at the base of a fast moving antarctic ice stream.

PubMed

Engelhardt, H; Humphrey, N; Kamb, B; Fahnestock, M

1990-04-06

Boreholes drilled to the bottom of ice stream B in the West Antarctic Ice Sheet reveal that the base of the ice stream is at the melting point and the basal water pressure is within about 1.6 bars of the ice overburden pressure. These conditions allow the rapid ice streaming motion to occur by basal sliding or by shear deformation of unconsolidated sediments that underlie the ice in a layer at least 2 meters thick. The mechanics of ice streaming plays a role in the response of the ice sheet to climatic change.

Magnetotelluric survey to characterize the Sunnyside porphyry copper system in the Patagonia Mountains, Arizona

USGS Publications Warehouse

Rodriguez, Brian D.; Sampson, Jay A.

2010-01-01

The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size and resistivity of the mineralized area beneath overburden, a regional east-west magnetotelluric sounding profile was acquired. This is a data release report of the magnetotelluric sounding data collected along the east-west profile; no interpretation of the data is included.

Drainage basin control of acid loadings to two Adirondack lakes

NASA Astrophysics Data System (ADS)

Booty, W. G.; Depinto, J. V.; Scheffe, R. D.

1988-07-01

Two adjacent Adirondack Park (New York) calibrated watersheds (Woods Lake and Cranberry Pond), which receive identical atmospheric inputs, generate significantly different unit area of watershed loading rates of acidity to their respective lakes. A watershed acidification model is used to evaluate the watershed parameters which are responsible for the observed differences in acid loadings to the lakes. The greater overall mean depth of overburden on Woods Lake watershed, which supplies a greater buffer capacity as well as a longer retention time of groundwater, appears to be the major factor responsible for the differences.

Horizontal cosmic ray muon radiography for imaging nuclear threats

NASA Astrophysics Data System (ADS)

Morris, Christopher L.; Bacon, Jeffrey; Borozdin, Konstantin; Fabritius, Joseph; Miyadera, Haruo; Perry, John; Sugita, Tsukasa

2014-07-01

Muon tomography is a technique that uses information contained in the Coulomb scattering of cosmic ray muons to generate three dimension images of volumes between tracking detectors. Advantages of this technique are the muons ability to penetrate significant overburden and the absence of any additional dose beyond the natural cosmic ray flux. Disadvantages include the long exposure times and limited resolution because of the low flux. Here we compare the times needed to image objects using both vertically and horizontally mounted tracking detectors and we develop a predictive model for other geometries.

A new method for imaging nuclear threats using cosmic ray muons

NASA Astrophysics Data System (ADS)

Morris, C. L.; Bacon, Jeffrey; Borozdin, Konstantin; Miyadera, Haruo; Perry, John; Rose, Evan; Watson, Scott; White, Tim; Aberle, Derek; Green, J. Andrew; McDuff, George G.; Lukić, Zarija; Milner, Edward C.

2013-08-01

Muon tomography is a technique that uses cosmic ray muons to generate three dimensional images of volumes using information contained in the Coulomb scattering of the muons. Advantages of this technique are the ability of cosmic rays to penetrate significant overburden and the absence of any additional dose delivered to subjects under study above the natural cosmic ray flux. Disadvantages include the relatively long exposure times and poor position resolution and complex algorithms needed for reconstruction. Here we demonstrate a new method for obtaining improved position resolution and statistical precision for objects with spherical symmetry.

Numerical simulation of groundwater flow in the Columbia Plateau Regional Aquifer System, Idaho, Oregon, and Washington

USGS Publications Warehouse

Ely, D. Matthew; Burns, Erick R.; Morgan, David S.; Vaccaro, John J.

2014-01-01

Groundwater pumping has increased substantially over the past 40–50 years; this increase resulted in declining water levels at depth and decreased base flows over much of the study area. The effects of pumping are mitigated somewhat by the increase of surface-water irrigation, especially in the shallow Overburden unit, and commingling wells in some areas. During dry to average years, groundwater pumping causes a net loss of groundwater in storage and current condition (2000–2007) groundwater pumping exceeds recharge in all but the wettest of years.

A new method for imaging nuclear threats using cosmic ray muons

DOE PAGES

Morris, C. L.; Bacon, Jeffrey; Borozdin, Konstantin; ...

2013-08-29

Muon tomography is a technique that uses cosmic ray muons to generate three-dimensional images of volumes using information contained in the Coulomb scattering of the muons. Advantages of this technique are the ability of cosmic rays to penetrate significant overburden and the absence of any additional dose delivered to subjects under study beyond the natural cosmic ray flux. Disadvantages include the relatively long exposure times and poor position resolution and complex algorithms needed for reconstruction. Furthermore, we demonstrate a new method for obtaining improved position resolution and statistical precision for objects with spherical symmetry.

The national coal-resources data system of the U.S. geological survey

USGS Publications Warehouse

Carter, M.D.

1976-01-01

The National Coal Resources Data System (NCRDS) was designed by the U.S. Geological Survey (USGS) to meet the increasing demands for rapid retrieval of information on coal location, quantity, quality, and accessibility. An interactive conversational query system devised by the USGS retrieves information from the data bank through a standard computer terminal. The system is being developed in two phases. Phase I, which currently is available on a limited basis, contains published areal resource and chemical data. The primary objective of this phase is to retrieve, calculate, and tabulate coal-resource data by area on a local, regional, or national scale. Factors available for retrieval include: state, county, quadrangle, township, coal field, coal bed, formation, geologic age, source and reliability of data, and coal-bed rank, thickness, overburden, and tonnage, or any combinations of variables. In addition, the chemical data items include individual values for proximate and ultimate analyses, BTU value, and several other physical and chemical tests. Information will be validated and deleted or updated as needed. Phase II is being developed to store, retrieve, and manipulate basic point source coal data (e.g., field observations, drill-hole logs), including geodetic location; bed thickness; depth of burial; moisture; ash; sulfur; major-, minor-, and trace-element content; heat value; and characteristics of overburden, roof rocks, and floor rocks. The computer system may be used to generate interactively structure-contour or isoline maps of the physical and chemical characteristics of a coal bed or to calculate coal resources. ?? 1976.

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.

Crestal fault geometries reveal late halokinesis and collapse of the Samson Dome, Northern Norway: Implications for petroleum systems in the Barents Sea

NASA Astrophysics Data System (ADS)

Mattos, Nathalia H.; Alves, Tiago M.; Omosanya, Kamaldeen O.

2016-10-01

This paper uses 2D and high-quality 3D seismic reflection data to assess the geometry and kinematics of the Samson Dome, offshore Norway, revising the implications of the new data to hydrocarbon exploration in the Barents Sea. The study area was divided into three (3) zones in terms of fault geometries and predominant strikes. Displacement-length (D-x) and Throw-depth (T-z) plots showed faults to consist of several segments that were later dip-linked. Interpreted faults were categorised into three families, with Type A comprising crestal faults, Type B representing large E-W faults, and Type C consisting of polygonal faults. The Samson Dome was formed in three major stages: a) a first stage recording buckling of the post-salt overburden and generation of radial faults; b) a second stage involving dissolution and collapse of the dome, causing subsidence of the overburden and linkage of initially isolated fault segments; and c) a final stage in which large fault segments were developed. Late Cretaceous faults strike predominantly to the NW, whereas NE-trending faults comprise Triassic structures that were reactivated in a later stage. Our work provides scarce evidence for the escape of hydrocarbons in the Samson Dome. In addition, fault analyses based on present-day stress distributions indicate a tendency for 'locking' of faults at depth, with the largest leakage factors occurring close to the surface. The Samson Dome is an analogue to salt structures in the Barents Sea where oil and gas exploration has occurred with varied degrees of success.

Muon background studies for shallow depth Double - Chooz near detector

NASA Astrophysics Data System (ADS)

Gómez, H.

2015-08-01

Muon events are one of the main concerns regarding background in neutrino experiments. The placement of experimental set-ups in deep underground facilities reduce considerably their impact on the research of the expected signals. But in the cases where the detector is installed on surface or at shallow depth, muon flux remains high, being necessary their precise identification for further rejection. Total flux, mean energy or angular distributions are some of the parameters that can help to characterize the muons. Empirically, the muon rate can be measured in an experiment by a number of methods. Nevertheless, the capability to determine the muons angular distribution strongly depends on the detector features, while the measurement of the muon energy is quite difficult. Also considering that on-site measurements can not be extrapolated to other sites due to the difference on the overburden and its profile, it is necessary to find an adequate solution to perform the muon characterization. The method described in this work to obtain the main features of the muons reaching the experimental set-up, is based on the muon transport simulation by the MUSIC software, combined with a dedicated sampling algorithm for shallow depth installations based on a modified Gaisser parametrization. This method provides all the required information about the muons for any shallow depth installation if the corresponding overburden profile is implemented. In this work, the method has been applied for the recently commissioned Double - Chooz near detector, which will allow the cross-check between the simulation and the experimental data, as it has been done for the far detector.

Steeply dipping heaving bedrock, Colorado: Part 3 - Environmental controls and heaving processes

USGS Publications Warehouse

Noe, D.C.; Higgins, J.D.; Olsen, H.W.

2007-01-01

This paper examines the environmental processes and mechanisms that govern differential heaving in steeply dipping claystone bedrock near Denver, Colorado. Three potential heave mechanisms and causal processes were evaluated: (1) rebound expansion, from reduced overburden stress; (2) expansive gypsum-crystal precipitation, from oxidation of pyrite; and (3) swelling of clay minerals, from increased ground moisture. First, we documented the effect of short-term changes in overburden stress, atmospheric exposure, and ground moisture on bedrock at various field sites and in laboratory samples. Second, we documented differential heaving episodes in outcrops and at construction and developed sites. We found that unloading and exposure of the bedrock in construction-cut areas are essentially one-time processes that result in drying and desiccation of the near-surface bedrock, with no visible heaving response. In contrast, wetting produces a distinct swelling response in the claystone strata, and it may occur repeatedly as natural precipitation or from lawn irrigation. We documented 2.5 to 7.5 cm (1 to 3 in.) of differential heaving in 24 hours triggered by sudden infiltration of water at the exposed ground surface in outcrops and at construction sites. From these results, we interpret that rebound and pyrite weathering, both of which figure strongly into the long-term geologic evolution of the geologic framework, do not appear to be major heave mechanisms at these excavation depths. Heaving of the claystone takes two forms: (1) hydration swelling of dipping bentonitic beds or zones, and (2) hydration swelling within bedrock blocks accommodated by lateral, thrust-shear movements, along pre-existing bedding and fracture planes.

Coal resources of the Alton, Utah, EMRIA site

USGS Publications Warehouse

Bowers, William E.; Aigen, A.A.; Landis, Edwin R.

1976-01-01

The estimated original identified coal resources of the Alton, Utah, EMRIA (Energy Minerals Rehabilitation Inventory and Analysis) site--an area of about 3.6 square miles (9.3 square kilometres)--total almost 49 million tons (45 megatonnes). A larger area that surrounds and includes the Alton EMRIA site proper contains estimated original identified coal resources of almost 309 million tons (281 megatonnes). Of these estimated resources in the EMRIA site proper, almost 27 million tons (25 megatonnes) are in beds more than 10 feet thick (3 metres); these beds are overlain by less-than 200 feet (60 metres) of overburden. In the larger area around and including the EMRIA site, about 88.5 million tons (81 megatonnes) are in beds more than ten feet (3 metres) thick with less than 200 feet (60 metres) of overburden. All the estimated resources are in the Smirl zone in the upper part of the Dakota Formation of Cretaceous age. The coal has an apparent rank of subbituminous B, an average heating value of about 9,560 Btu, an average sulfur content of about 1.0 percent, and an average ash content of 7.2 percent. When compared with the average abundance of elements in the crust of the Earth as a whole, only selenium and boron were present in the Alton area coal samples in amounts an order of magnitude greater than the average crustal abundance. Beryllium, fluorine, nickel, zinc, and zirconium are all present in the Alton area samples in amounts that are about an order of magnitude less than the average crustal abundance.

Sand resources, regional geology, and coastal processes for shoreline restoration: case study of Barataria shoreline, Louisiana

USGS Publications Warehouse

Kindinger, Jack G.; Flocks, James G.; Kulp, Mark; Penland, Shea; Britsch, Louis D.

2002-01-01

The Louisiana barrier shoreline of Barataria Basin, which lies within the western Mississippi River delta, has undergone significant retreat during the past 100 years. The most practical restoration method to rebuild these shorelines is sand nourishment. Seismic and sonar interpretations verified with geologic samples (vibracores and borings) indicate that there are nine sand targets within the Barataria study area that meet or exceed the minimum criteria for potential resource sites. However, the near surface lithology in the basin is typically silts and clays. Locating suitable sand resources for shoreline restoration is challenging. The sand units are associated with geologic depositional systems such as ebb-tidal deltas, distributary mouth bars, and channel fill (undifferentiated fluvial or tidal inlet channels). The nine potential sand targets consist primarily of fine sand and can be delineated into three surficial and six buried features. The surficial features contain approximately 10% of the total sand resources identified. At least 90% of the sand resources need overburden sediment removed prior to use; almost 570 million yd3 (438.5 mil m3) of overburden will need to be removed if the entire resource is mined. In this study, we identified 396 to 532 mil yd3 (305.8 to 410.8 mil m3) of potential sand deposits for shoreline restoration. Previous studies using less dense survey methods greatly over-estimated sand resources available in this area. Many fluvial channels reported previously as sand-filled are mud-filled. Contrary to these previous studies, few fluvial subsystems in this region have abundant sand resources.

Analysis of the current rib support practices and techniques in U.S. coal mines

PubMed Central

Mohamed, Khaled M.; Murphy, Michael M.; Lawson, Heather E.; Klemetti, Ted

2016-01-01

Design of rib support systems in U.S. coal mines is based primarily on local practices and experience. A better understanding of current rib support practices in U.S. coal mines is crucial for developing a sound engineering rib support design tool. The objective of this paper is to analyze the current practices of rib control in U.S. coal mines. Twenty underground coal mines were studied representing various coal basins, coal seams, geology, loading conditions, and rib control strategies. The key findings are: (1) any rib design guideline or tool should take into account external rib support as well as internal bolting; (2) rib bolts on their own cannot contain rib spall, especially in soft ribs subjected to significant load—external rib control devices such as mesh are required in such cases to contain rib sloughing; (3) the majority of the studied mines follow the overburden depth and entry height thresholds recommended by the Program Information Bulletin 11-29 issued by the Mine Safety and Health Administration; (4) potential rib instability occurred when certain geological features prevailed—these include draw slate and/or bone coal near the rib/roof line, claystone partings, and soft coal bench overlain by rock strata; (5) 47% of the studied rib spall was classified as blocky—this could indicate a high potential of rib hazards; and (6) rib injury rates of the studied mines for the last three years emphasize the need for more rib control management for mines operating at overburden depths between 152.4 m and 304.8 m. PMID:27648341

Geology of the Cooper Ridge NE Quadrangle, Sweetwater County, Wyoming

USGS Publications Warehouse

Roehler, Henry W.

1979-01-01

The Cooper Ridge NE 7?-minute quadrangle is 18 miles southeast of Rock Springs, Wyo., on the east flank of the Rock Springs uplift. Upper Cretaceous rocks composing the Rock Springs Formation, Ericson Sandstone, Almond Formation, Lewis Shale, Fox Hills Sandstone, and Lance Formation, Paleocene rocks composing the Fort Union Formation, and Eocene rocks composing the Wasatch Formation are exposed and dip 5?-8? southeast. Outcrops are unfaulted and generally homoclinal, but a minor cross-trending fold, the Jackknife Spring anticline, plunges southeastward and interrupts the northeast strike of beds. Older rocks in the subsurface are faulted and folded, especially near the Brady oil and gas field. Coal beds are present in the Almond, Lance, and Fort Union Formations. Coal resources are estimated to be more than 762 million short tons in 16 beds more than 2.5 feet thick, under less than 3,000 ft of overburden. Nearly 166 million tons are under less than 200 ft of overburden and are recoverable by strip mining. Unknown quantities of oil and gas are present in the Cretaceous Rock Springs, Blair, and Dakota Formations, Jurassic sandstone (Entrada Sandstone of drillers), Jurassic(?) and Triassic(?) Nugget Sandstone, Permian Park City Formation, and Pennsylvanian and Permian Weber Sandstone at the Brady field, part of which is in the southeast corner of the quadrangle, and in the Dakota Sandstone at the Prenalta Corp. Bluewater 33-32 well near the northern edge of the quadrangle. Other minerals include uranium in the Almond Formation and titanium in the Rock Springs Formation.

Engineering assessment of low-level liquid waste disposal caisson locations at the 618-11 Burial Grounds

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

Phillips, S.J.; Fischer, D.D.; Crawford, R.C.

1982-06-01

Rockwell Hanford Operations is currently involved in an extensive effort to perform interim ground surface stabilization activities at retired low-level waste burial grounds located at the Hanford Site, Richland, Washington. The principal objective of these activities is to promote increased occupational and radiological safety at burial grounds. Interim stabilization activities include: (1) load testing (traversing burial ground surfaces with heavy equipment to promote incipient collapse of void spaces within the disposal structure and overburden), (2) barrier placement (placement of a {ge} 0.6 m soil barrier over existing overburden), and (3) revegetation (establishment of shallow rooted vegetation on the barrier tomore » mitigate deep rooted plant growth and to reduce erosion). Low-level waste disposal caissons were used in 300 Area Burial Grounds as internment structures for containerized liquid wastes. These caissons, by virtue of their contents, design and methods of closure, require long-term performance evaluation. As an initial activity to evaluate long-term performance, the accurate location of these structures is required. This topical report summarizes engineering activities used to locate caissons in the subsurface environment at the Burial Ground. Activities were conducted to locate caissons during surface stabilization activities. The surface locations were marked, photographed, and recorded on an as built engineering drawing. The recorded location of these caissons will augment long-term observations of confinement structure and engineered surface barrier performance. In addition, accurate caisson location will minimize occupational risk during monitoring and observation activities periodically conducted at the burial ground.« less

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

Kasmer, O.; Ulusay, R.

One of the major problems in surface mining of coal is the stability of disposed overburden materials. Geotechnical considerations are thus very important in rational planning for disposal, reclamation, treatment, and utilization of mine waste material. The subject of this study is the stability of spoil piles at open pit coal mines located in the Central Anatolia, Turkey. The coal is produced from two adjacent open pits. While a large portion of the spoil piles dumped at the Central Pit has experienced slope failure, no spoil pile instability has been experienced at the South Pit. This article outlines the resultsmore » of field and laboratory investigations to describe the mechanism of the spoil pile failure in the Central Pit and the geotechnical design considerations for the spoil piles at the South Pit based on the experience gained from the previous spoil failures. Limit equilibrium analysis carried out for the large-scale spoil failure indicated that deep-seated sliding along the interface between underclay and dragline spoil piles and rotational slip through the overburden spoil material may be all occurring simultaneously as water migrates through these areas. Sensitivity analyses revealed that spoil pile instability is not expected at the South Pit when the current spoil placement method is used as long as the generation of high water pressures in the spoil piles is not permitted. Comparisons between the results of finite element analysis and long-term monitoring data also confirmed the results of sensitivity analyses and indicated a vertical deformation associated with compaction of the spoil material.« less

Large-scale mechanical buckle fold development and the initiation of tensile fractures

NASA Astrophysics Data System (ADS)

Eckert, Andreas; Connolly, Peter; Liu, Xiaolong

2014-11-01

failure associated with buckle folding is commonly associated to the distribution of outer arc extension but has also been observed on fold limbs. This study investigates whether tensile stresses and associated failure can be explained by the process of buckling under realistic in situ stress conditions. A 2-D plane strain finite element modeling approach is used to study single-layer buckle folds with a Maxwell viscoelastic rheology. A variety of material parameters are considered and their influence on the initiation of tensile stresses during the various stages of deformation is analyzed. It is concluded that the buckling process determines the strain distribution within the fold layer but is not solely responsible for the initiation of tensile stresses. The modeling results show that tensile stresses are most dependent on the permeability, viscosity, and overburden thickness. Low permeability (<10-19 m2), high viscosity (≥1021 Pa s), and low overburden pressure can explain tensile failure at the fold hinge. Tensile stresses in the limb of the fold cannot (in general) be explained by buckling. Rather, it develops due to a combination of compression and erosional unloading. The modeling results show that erosion of high permeability rocks can explain the generation of tensile stresses at significant depths (˜2 km) both at the hinge of the fold and throughout the limb of the fold. This study shows that tensile stresses and associated failure within buckle folds is directly dependent on the distribution of material parameters but moreover to the strain history of the geologic system.

Instrument Correction and Dynamic Site Profile Validation at the Central United States Seismic Observatory, New Madrid Seismic Zone

NASA Astrophysics Data System (ADS)

Brengman, C.; Woolery, E. W.; Wang, Z.; Carpenter, S.

2016-12-01

The Central United States Seismic Observatory (CUSSO) is a vertical seismic array located in southwestern Kentucky within the New Madrid seismic zone. It is intended to describe the effects of local geology, including thick sediment overburden, on seismic-wave propagation, particularly strong-motion. The three-borehole array at CUSSO is composed of seismic sensors placed on the surface, and in the bedrock at various depths within the 585 m thick sediment overburden. The array's deep borehole provided a unique opportunity in the northern Mississippi embayment for the direct geological description and geophysical measurement of the complete late Cretaceous-Quaternary sediment column. A seven layer, intra-sediment velocity model is interpreted from the complex, inhomogeneous stratigraphy. The S- and P-wave sediment velocities range between 160 and 875 m/s and between 1000 and 2300 m/s, respectively, with bedrock velocities of 1452 and 3775 m/s, respectively. Cross-correlation and direct comparisons were used to filter out the instrument response and determine the instrument orientation, making CUSSO data ready for analysis, and making CUSSO a viable calibration site for other free-field sensors in the area. The corrected bedrock motions were numerically propagated through the CUSSO soil profile (transfer function) and compared, in terms of both peak acceleration and amplitude spectra, to the recorded surface observations. Initial observations reveal a complex spectral mix of amplification and de-amplification across the array, indicating the site effect in this deep sediment setting is not simply generated by the shallowest layers.

Modeling of Three Flat Coal Seams Strata Developing at Open Pit Miming

NASA Astrophysics Data System (ADS)

Gvozdkova, Tatiana; Markov, Sergey; Demirel, Nuray; Anyona, Serony

2017-11-01

The use of low-cost direct dumpling technology, as is well known, has a relatively limited field of application: flat coal seams, and the higher the dip angle of the seam, the more difficult it is to place the necessary volume of overburden rock in the dumping layers. For this, we have to pour four-tier dumps. In this article, four possible options for piling the dump have been studied and prerequisites have been made for further research aimed at improving the efficiency of the use of direct dumpling technology in the development of flat coal seams.

A synoptic description of coal basins via image processing

NASA Technical Reports Server (NTRS)

Farrell, K. W., Jr.; Wherry, D. B.

1978-01-01

An existing image processing system is adapted to describe the geologic attributes of a regional coal basin. This scheme handles a map as if it were a matrix, in contrast to more conventional approaches which represent map information in terms of linked polygons. The utility of the image processing approach is demonstrated by a multiattribute analysis of the Herrin No. 6 coal seam in Illinois. Findings include the location of a resource and estimation of tonnage corresponding to constraints on seam thickness, overburden, and Btu value, which are illustrative of the need for new mining technology.

Audio-magnetotelluric survey to characterize the Sunnyside porphyry copper system in the Patagonia Mountains, Arizona

USGS Publications Warehouse

Sampson, Jay A.; Rodriguez, Brian D.

2010-01-01

The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size, resistivity, and skin depth of the polarizable mineral deposit concealed beneath thick overburden, a regional east-west audio-magnetotelluric sounding profile was acquired. The purpose of this report is to release the audio-magnetotelluric sounding data collected along that east-west profile. No interpretation of the data is included.

3D Tomography of a Mesa Using Cosmic Ray Muons Detected in an Underground Tunnel

NASA Astrophysics Data System (ADS)

Guardincerri, E.; Rowe, C. A.

2016-12-01

The LANL Mini Muon Tracker (MMT) is a muon tracking detector made of sealed aluminum drift tubes. The MMT was operated at four locations inside a tunnel under the Los Alamos town site mesa between November 2015 and February 2016 and it collected cosmic ray muons attenuated by the tunnel overburden. The data were analyzed and used to obtain a 3D tomographic image of the mesa and will be later combined with gravity data collected around the same location. We describe here the muon data taking and their analysis, and we show the resulting 3D image.

A computer program for calculating relative-transmissivity input arrays to aid model calibration

USGS Publications Warehouse

Weiss, Emanuel

1982-01-01

A program is documented that calculates a transmissivity distribution for input to a digital ground-water flow model. Factors that are taken into account in the calculation are: aquifer thickness, ground-water viscosity and its dependence on temperature and dissolved solids, and permeability and its dependence on overburden pressure. Other factors affecting ground-water flow are indicated. With small changes in the program code, leakance also could be calculated. The purpose of these calculations is to provide a physical basis for efficient calibration, and to extend rational transmissivity trends into areas where model calibration is insensitive to transmissivity values.

RECOZ data reduction and analysis: Programs and procedures

NASA Technical Reports Server (NTRS)

Reed, E. I.

1984-01-01

The RECOZ data reduction programs transform data from the RECOZ photometer to ozone number density and overburden as a function of altitude. Required auxiliary data are the altitude profile versus time and for appropriate corrections to the ozone cross sections and scattering effects, air pressure and temperature profiles. Air temperature and density profiles may also be used to transform the ozone density versus geometric altitude to other units, such as to ozone partial pressure or mixing ratio versus pressure altitude. There are seven programs used to accomplish this: RADAR, LISTRAD, RAW OZONE, EDIT OZONE, MERGE, SMOOTH, and PROFILE.

The Impact of Inter-Governmental Grants and Municipal Overburden on School Spending and Simulations of the Impact of Alternative Grant Formulas. [and] Policy Proposals Resulting from Research on "The Impact of Intergovernmental Grants and Municipal Overburden on School Finance Equity."

ERIC Educational Resources Information Center

Conte, Michael; And Others

In five chapters, this document's first part reports on research on the interrelationship of school and municipal finance in New Hampshire. The document's second part briefly summarizes the research report and discusses policy changes suggested by the results. Chapter 1 of the research report describes New Hampshire schools and the state aid…

Stripping-coal deposits on lower Lignite Creek, Nenana coal field, Alaska

USGS Publications Warehouse

Wahrhaftig, Clyde; Birman, Joseph H.

1954-01-01

Stripping-coal reserves in an area of about 9.4 square miles extending from the Nenana River about 6 miles up the valley of Lignite Creek are estimated to amount to about 95, 000, 000 tons. The stripping-coal reserves are located in the lower and middle members of the Tertiary coal-bearing formation. Five continuous beds in the middle member range in thickness from 5 to 30 feet, and a discontinuous bed at the base of the lower member is about 60 feet thick. Analyses of outcrop samples, as received at the laboratory, show a heating content of 7,500--8,200 Btu, an ash content of 6 to 14 percent, and a moisture content of 25 percent. The reserve estimate is based on a maximum thickness of overburden of 200 feet. Coal below the level of Lignite Creek or its major tributaries was not considered as it was assumed that stripping would be by hydraulic methods. Uncertainties regarding the position of the coal outcrops and the extent of burning of the coal beds are the basis for a recommendation that, where possible, the stripping reserves be tested by drilling. Overburden consists largely of weakly consolidated sandstone and includes some coarse gravel and a few boulders 20 feet or more in diameter. Water for hydraulic mining can be obtained from the Nenana River. Lignite Creek does not appear to be a dependable source. Disposal of debris may affect the channel of the Nenana River causing damage to railroads and structures. Landslides are common in the valley of Lignite Creek and will affect mining operations and transportation routes.

Uncertainty quantification and risk analyses of CO2 leakage in heterogeneous geological formations

NASA Astrophysics Data System (ADS)

Hou, Z.; Murray, C. J.; Rockhold, M. L.

2012-12-01

A stochastic sensitivity analysis framework is adopted to evaluate the impact of spatial heterogeneity in permeability on CO2 leakage risk. The leakage is defined as the total mass of CO2 moving into the overburden through the caprock-overburden interface, in both gaseous and liquid (dissolved) phases. The entropy-based framework has the ability to quantify the uncertainty associated with the input parameters in the form of prior pdfs (probability density functions). Effective sampling of the prior pdfs enables us to fully explore the parameter space and systematically evaluate the individual and combined effects of the parameters of interest on CO2 leakage risk. The parameters that are considered in the study include: mean, variance, and horizontal to vertical spatial anisotropy ratio for caprock permeability, and those same parameters for reservoir permeability. Given the sampled spatial variogram parameters, multiple realizations of permeability fields were generated using GSLIB subroutines. For each permeability field, a numerical simulator, STOMP, (in the water-salt-CO2-energy operational mode) is used to simulate the CO2 migration within the reservoir and caprock up to 50 years after injection. Due to intensive computational demand, we run both a scalable version simulator eSTOMP and serial STOMP on various supercomputers. We then perform statistical analyses and summarize the relationships between the parameters of interest (mean/variance/anisotropy ratio of caprock and reservoir permeability) and CO2 leakage ratio. We also present the effects of those parameters on CO2 plume radius and reservoir injectivity. The statistical analysis provides a reduced order model that can be used to estimate the impact of heterogeneity on caprock leakage.

The Influence of Surface Coal Mining on Runoff Processes and Stream Chemistry in the Elk Valley, British Colubmbia, Canada

NASA Astrophysics Data System (ADS)

Carey, S. K.; Wellen, C. C.; Shatilla, N. J.

2015-12-01

Surface mining is a common method of accessing coal. In high-elevation environments, vegetation and soils are typically removed prior to the blasting of overburden rock, thereby allowing access to mineable ore. Following this, the removed overburden rock is deposited in adjacent valleys as waste rock spoils. Previous research has identified that areas downstream of surface coal mining have impaired water quality, yet there is limited information about the interaction of hydrology and geochemistry across a range of mining conditions, particularly at the headwater scale. Here, we provide an analysis of an extensive long-term data set of geochemistry and flows across a gradient of coal mining in the Elk Valley, British Columbia, Canada. This work is part of a broader R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley aimed at informing effective management responses. Results indicate that water from waste rock piles has an ionic profile distinct from unimpacted catchments. While the concentration of geochemicals increased with the degree of mine impact, the control of hydrological transport capacity over geochemical export did not vary with degree of mine impact. Geochemical export in mine-influenced catchments was limited more strongly by transport capacity than supply, implying that more water moving through the waste rock mobilized more geochemicals. Placement of waste rock within the catchment (headwaters or outlet) did not affect chemical concentrations but did alter the timing with which chemically distinct water mixed. This work advances on results reported earlier using empirical models of selenium loading and further highlights the importance of limiting water inputs into waste rock piles.

Investigation of guided waves propagation in pipe buried in sand

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

Leinov, Eli; Cawley, Peter; Lowe, Michael J.S.

The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand usingmore » a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence.« less

Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production

USGS Publications Warehouse

Rutqvist, J.; Moridis, G.J.; Grover, T.; Collett, T.

2009-01-01

In this simulation study, we analyzed the geomechanical response during depressurization production from two known hydrate-bearing permafrost deposits: the Mallik (Northwest Territories, Canada) deposit and Mount Elbert (Alaska, USA) deposit. Gas was produced from these deposits at constant pressure using horizontal wells placed at the top of a hydrate layer (HL), located at a depth of about 900??m at the Mallik site and 600??m at the Mount Elbert site. The simulation results show that general thermodynamic and geomechanical responses are similar for the two sites, but with substantially higher production and more intensive geomechanical responses at the deeper Mallik deposit. The depressurization-induced dissociation begins at the well bore and then spreads laterally, mainly along the top of the HL. The depressurization results in an increased shear stress within the body of the receding hydrate and causes a vertical compaction of the reservoir. However, its effects are partially mitigated by the relatively stiff permafrost overburden, and compaction of the HL is limited to less than 0.4%. The increased shear stress may lead to shear failure in the hydrate-free zone bounded by the HL overburden and the downward-receding upper dissociation interface. This zone undergoes complete hydrate dissociation, and the cohesive strength of the sediment is low. We determined that the likelihood of shear failure depends on the initial stress state as well as on the geomechanical properties of the reservoir. The Poisson's ratio of the hydrate-bearing formation is a particularly important parameter that determines whether the evolution of the reservoir stresses will increase or decrease the likelihood of shear failure.

Inversion and Prediction of Consolidation Settlement Characteristics of the Fluvial Sediments Based on Void Ratio Variation in the Northern Modern Yellow River Subaqueous Delta, China

NASA Astrophysics Data System (ADS)

Liu, Xiao; Liu, Jie; Feng, Xiuli

2018-06-01

The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacted and consolidate under the geostatic stress and overburden stress. It is one of the key areas with land subsidence disasters in China, bringing a series of safety hazards to production and living. Based on the data of massive surface cores and ten drill holes ranging from 12 to 40 m obtained from the northern modern Yellow River subaqueous delta, the inversion method suitable for the calculation of consolidation settlement characteristics of the modern Yellow River subaqueous delta is discussed, and the consolidation settlement characteristics of the delta sediments are inversed and predicted in this paper. The actual void ratio of the delta sediments at the depth from 3 to 15 m shows a significant power function relationship with the depth, while the void ratio of the sediments below 15 m changes little with depth. The pre-consolidation settlement (from deposition to sampling) of the delta sediments is between 0.91 and 1.96 m, while the consolidation settlement of unit depth is between 9.6 and 14.0 cm m-1. The post-consolidation settlement (from sampling to stable) of the subaqueous delta sediments is between 0.65 and 1.56 m in the later stage, and the consolidation settlement of unit depth is between 7.6 and 13.1 cm m-1 under the overburden stress. The delta sediments with a buried depth of 3 to 7 m contribute the most to the possible consolidation settlement in the later stage.

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

Gómez, H.

Muon events are one of the main concerns regarding background in neutrino experiments. The placement of experimental set-ups in deep underground facilities reduce considerably their impact on the research of the expected signals. But in the cases where the detector is installed on surface or at shallow depth, muon flux remains high, being necessary their precise identification for further rejection. Total flux, mean energy or angular distributions are some of the parameters that can help to characterize the muons. Empirically, the muon rate can be measured in an experiment by a number of methods. Nevertheless, the capability to determine themore » muons angular distribution strongly depends on the detector features, while the measurement of the muon energy is quite difficult. Also considering that on-site measurements can not be extrapolated to other sites due to the difference on the overburden and its profile, it is necessary to find an adequate solution to perform the muon characterization. The method described in this work to obtain the main features of the muons reaching the experimental set-up, is based on the muon transport simulation by the MUSIC software, combined with a dedicated sampling algorithm for shallow depth installations based on a modified Gaisser parametrization. This method provides all the required information about the muons for any shallow depth installation if the corresponding overburden profile is implemented. In this work, the method has been applied for the recently commissioned Double - Chooz near detector, which will allow the cross-check between the simulation and the experimental data, as it has been done for the far detector.« less

Assessment of carbon sequestration potential of revegetated coal mine overburden dumps: A chronosequence study from dry tropical climate.

PubMed

Ahirwal, Jitendra; Maiti, Subodh Kumar

2017-10-01

Development of secondary forest as post-mining land use in the surface coal mining degraded sites is of high research interest due to its potential to sequester atmospheric carbon (C). The objectives of this study were to assess the improvement in mine soil quality and C sequestration potential of the post-mining reclaimed land with time. Hence, this study was conducted in reclaimed chronosequence sites (young, intermediate and old) of a large open cast coal project (Central Coal Fields Limited, Jharkhand, India) and results were compared to a reference forest site (Sal forest, Shorea robusta). Mine soil quality was assessed in terms of accretion of soil organic carbon (SOC), available nitrogen (N) and soil CO 2 flux along with the age of revegetation. After 14 years of revegetation, SOC and N concentrations increased three and five-fold, respectively and found equivalent to the reference site. Accretion of SOC stock was estimated to be 1.9 Mg C ha -1 year -1 . Total ecosystem C sequestered after 2-14 years of revegetation increased from 8 Mg C ha -1 to 90 Mg C ha -1 (30-333 Mg CO 2 ha -1 ) with an average rate of 6.4 Mg C ha -1 year -1 . Above ground biomass contributes maximum C sequestrate (50%) in revegetated site. CO 2 flux increased with age of revegetation and found 11, 33 and 42 Mg CO 2 ha -1 year -1 in younger, intermediate and older dumps, respectively. Soil respiration in revegetated site is more influenced by the temperature than soil moisture. Results of the study also showed that trees like, Dalbergia sissoo and Heterophragma adenophyllum should be preferred for revegetation of mine degraded sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

Organizational stress and individual strain: A social-psychological study of risk factors in coronary heart disease among administrators, engineers, and scientists

NASA Technical Reports Server (NTRS)

Caplan, R. D.

1971-01-01

It is hypothesized that organizational stresses, such as high quantitative work load, responsibility for persons, poor relations with role senders, and contact with alien organizational territories, may be associated with high levels of psychological and physiological strain which are risk factors in coronary heart disease. It is further hypothesized that persons with coronary-prone Type A personality characteristics are most likely to exhibit strain under conditions of organizational stress. Measures of these stresses, personality traits, and strains were obtained from 205 male NASA administrators, engineers, and scientists. Type A personality measures included sense of time urgency, persistence, involved striving, leadership, and preference for competitive and environmentally overburdening situations.

Measurement of the residual energy of muons in the Gran Sasso underground laboratories

NASA Astrophysics Data System (ADS)

MACRO Collaboration; Ambrosio, M.; Antolini, R.; Baldini, A.; Barbarino, G. C.; Barish, B. C.; Battistoni, G.; Becherini, Y.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bower, C.; Brigida, M.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Carboni, M.; Caruso, R.; Cecchini, S.; Cei, F.; Chiarella, V.; Choudhary, B. C.; Coutu, S.; Cozzi, M.; de Cataldo, G.; Dekhissi, H.; de Marzo, C.; de Mitri, I.; Derkaoui, J.; de Vincenzi, M.; di Credico, A.; Erriquez, O.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Giorgini, M.; Grassi, M.; Grillo, A.; Guarino, F.; Gustavino, C.; Habig, A.; Hanson, K.; Heinz, R.; Iarocci, E.; Katsavounidis, E.; Katsavounidis, I.; Kearns, E.; Kim, H.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D. S.; Lipari, P.; Longley, N. P.; Longo, M. J.; Loparco, F.; Mancarella, G.; Mandrioli, G.; Margiotta, A.; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M. N.; Michael, D. G.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicolò, D.; Nolty, R.; Orth, C.; Osteria, G.; Palamara, O.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C. W.; Perrone, L.; Petrera, S.; Pistilli, P.; Popa, V.; Rainò, A.; Reynoldson, J.; Ronga, F.; Satriano, C.; Scapparone, E.; Scholberg, K.; Sciubba, A.; Serra, P.; Sioli, M.; Sirri, G.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J. L.; Sulak, L. R.; Surdo, A.; Tarlè, G.; Vakili, M.; Walter, C. W.; Webb, R.

2003-06-01

The MACRO detector was located in the Hall B of the Gran Sasso underground laboratories under an average rock overburden of 3700 hg/cm2. A transition radiation detector composed of three identical modules, covering a total horizontal area of 36 m2, was installed inside the empty upper part of the detector in order to measure the residual energy of muons. This paper presents the measurement of the residual energy of single and double muons crossing the apparatus. Our data show that double muons are more energetic than single ones. This measurement is performed over a standard rock depth range from 3000 to 6500 hg/cm2.

Tests of cosmic ray radiography for power industry applications

NASA Astrophysics Data System (ADS)

Durham, J. M.; Guardincerri, E.; Morris, C. L.; Bacon, J.; Fabritius, J.; Fellows, S.; Poulson, D.; Plaud-Ramos, K.; Renshaw, J.

2015-06-01

In this report, we assess muon multiple scattering tomography as a non-destructive inspection technique in several typical areas of interest to the nuclear power industry, including monitoring concrete degradation, gate valve conditions, and pipe wall thickness. This work is motivated by the need for imaging methods that do not require the licensing, training, and safety controls of x-rays, and by the need to be able to penetrate considerable overburden to examine internal details of components that are otherwise inaccessible, with minimum impact on industrial operations. In some scenarios, we find that muon tomography may be an attractive alternative to more typical measurements.

Design and implementation of a secure workflow system based on PKI/PMI

NASA Astrophysics Data System (ADS)

Yan, Kai; Jiang, Chao-hui

2013-03-01

As the traditional workflow system in privilege management has the following weaknesses: low privilege management efficiency, overburdened for administrator, lack of trust authority etc. A secure workflow model based on PKI/PMI is proposed after studying security requirements of the workflow systems in-depth. This model can achieve static and dynamic authorization after verifying user's ID through PKC and validating user's privilege information by using AC in workflow system. Practice shows that this system can meet the security requirements of WfMS. Moreover, it can not only improve system security, but also ensures integrity, confidentiality, availability and non-repudiation of the data in the system.

Tests of cosmic ray radiography for power industry applications

DOE PAGES

Durham, J. M.; Guardincerri, E.; Morris, C. L.; ...

2015-06-30

In this report, we assess muon multiple scattering tomography as a non-destructive inspection technique in several typical areas of interest to the nuclear power industry, including monitoring concrete degradation, gate valve conditions, and pipe wall thickness. This work is motivated by the need for imaging methods that do not require the licensing, training, and safety controls of x-rays, and by the need to be able to penetrate considerable overburden to examine internal details of components that are otherwise inaccessible, with minimum impact on industrial operations. In some instances, we find that muon tomography may be an attractive alternative to moremore » typical measurements.« less

Geohydrology and evaluation of water-resource potential of the upper Floridan Aquifer in the Albany area, southwestern Georgia

USGS Publications Warehouse

Torak, L.J.; Davis, G.S.; Strain, G.A.; Herndon, J.G.

1993-01-01

In the Albany area of southwestern Georgia, the Upper Floridan aquifer lies entirely within the Dougherty Plain district of the Coastal Plain physiographic province, and consists of the Ocala Limestone of late Eocene age. The aquifer is divided throughout most of the study area into an upper and a lower lithologic unit, which creates an upper and a lower water-bearing zone. The lower waterbearing zone consists of alternating layers of sandy limestone and medium-brown, recrystallized dolomitic limestone, and ranges in thickness from about 50 ft to 100 ft. It is highly fractured and exhibits well-developed permeability by solution features that are responsible for transmitting most of the ground water in the aquifer. Transmissivity of the lower water-bearing zone ranges from about 90,000 to 178,000 ft2/d. The upper water-bearing zone is a finely crystallized-to-oolitic, locally dolomitic limestone having an average thickness of about 60 ft. Transmissivities are considerably less in the upper water-bearing zone than in the lower water-bearing zone. The Upper Floridan aquifer is overlain by about 20-120 ft of undifferentiated overburden consisting of fine-to-coarse quartz sand and noncalcareous clay. A clay zone about 10-30 ft thick may be continuous throughout the southwestern part of the Albany area and, where present, causes confinement of the Upper Floridan aquifer and creates perched ground water after periods of heavy rainfall. The Upper Floridan aquifer is confined below by the Lisbon Formation, a mostly dolomitic limestone that contains trace amounts of glauconite. The Lisbon Formation is at least 50 ft thick in the study area and acts as an impermeable base to the Upper Floridan aquifer. The quality of ground water in the Upper Floridan aquifer is suitable for most uses; wells generally yield water of the hard, calcium-bicarbonate type that meets the U.S. Environmental Protection Agency's Primary or Secondary Drinking-Water Regulations. The water

AfricaArray International Geophysics Field School: Applications of Near Surface Geophysics to challenges encountered in mine planning

NASA Astrophysics Data System (ADS)

Webb, S. J.; Jones, M. Q.; Durrheim, R. J.; Nyblade, A.; Snyman, Q.

2012-12-01

Hard rock exploration and mining presents many opportunities for the effective use of near surface geophysics. For over 10 years the AfricaArray international geophysics field school has been hosted at a variety of mines in South Africa. While the main objective of the field school is practical training for the next generation of geophysicists, being hosted at a mine has allowed us to investigate applications of near surface geophysics in the early stages of mine planning and development as geophysics is often cheaper and faster than drilling. Several applications include: detailed delineation of dykes and stringer dykes, physical property measurements on drill core for modeling and marker horizons, determination of overburden thickness, locations of water and faults. Dolerite dykes are usually magnetic and are associated with loss of ground (i.e. where the dyke replaces the ore and thus reduces the amount of ore available) and safety/stability concerns. Thus the accurate mapping of dykes and narrow stringers that are associated with them are crucial to the safe planning of a mine. We have acquired several case studies where ground magnetic surveys have greatly improved on the resolution and detail of airborne magnetic surveys in regions of complicated dyke swarms. In many cases, thin stringer dykes of less than 5 cm have been detected. Physical property measurements of these dykes can be used to distinguish between different ages of dykes. It is important to accurately determine overburden thickness when planning an open pit mine as this directly affects the cost of development. Depending on the nature of the overburden, both refraction seismic and or DC resistivity can provide continuous profiling in the area of interest that fills in gaps between boreholes. DC resistivity is also effective for determining water associated with dykes and structures that may affect mine planning. The field school mainly addresses the training of a variety of students. The core

Late Cenozoic regional collapse due to evaporite flow and Dissolution in the Carbondale Collapse Center, West-Central Colorado

USGS Publications Warehouse

Kirkham, R.M.; Streufert, R.K.; Budahn, J.R.; Kunk, Michael J.; Perry, W.J.

2001-01-01

Dissolution and flow of Pennsylvanian evaporitic rocks in west-central Colorado created the Carbondale Collapse Center, a 450 mi2 structural depression with about 4,000 ft of vertical collapse during the late Cenozoic. This paper describes evidence of collapse in the lower Roaring Fork River valley. Both the lateral extent and amount of vertical collapse is constrained by deformed upper Cenozoic volcanic rocks that have been correlated using field mapping, 40Ar/39Ar geochronology, geochemistry, and paleomagnetism. The Carbondale Collapse Center is one of at least two contiguous areas that have experienced major evaporite tectonism during the late Cenozoic. Historic sinkholes, deformed Holocene deposits, and modern high-salinity loads in the rivers and thermal springs indicate the collapse process continues today. Flow of evaporitic rocks is an important element in the collapse process, and during initial stages of collapse it was probably the primary causative mechanism. Dissolution, however, is the ultimate means by which evaporite is removed from the collapse area. As the Roaring Fork River began to rapidly down-cut through a broad volcanic plateau during the late Miocene, the underlying evaporite beds were subjected to differential overburden pressures. The evaporitic rocks flowed from beneath the upland areas where overburden pressures remained high, toward the Roaring Fork River Valley where the pressures were much lower. Along the valley the evaporitic rocks rose upward, sometimes as diapirs, forming or enhancing a valley anticline in bedrock and locally upwarping Pleistocene terraces. Wherever the evaporites encountered relatively fresh ground water, they were dissolved, forming underground voids into which overlying bedrock and surficial deposits subsided. The saline ground water eventually discharged to streams and rivers through thermal springs and by seepage into alluvial aquifers.

Unstable ground in western North Dakota

USGS Publications Warehouse

Trimble, Donald E.

1979-01-01

Unstable ground in western North Dakota is mainly the result of mass-wasting processes. The units most affected are mudstones, siltstones, and sandstones of the Fort Union Formation. Ground instability generally is indicated by landslides, soil slides, or subsidence. Landslides are mostly of the slump-earthflow type and are localized along the flanks of the high buttes in southwestern North Dakota, including HT (Black) Butte, Chalky Buttes, Sentinel Butte, and East and West Rainy Buttes, and along parts of the valleys of the Des Lacs, Missouri, Little Missouri, and Heart Rivers. Landslides are sparse elsewhere. Soil slides are common in the areas south and southwest of the maximum position of the Pleistocene glacial ice margin on slopes of 15 degrees or more, and have taken place on some slopes as gentle as five degrees. The weathered, exposed surface of the Fort Union Formation seems to be especially susceptible to soil slides. Soil slides constitute the major type of ground instability in southwestern North Dakota. Subsidence is of two types: (1) subsidence over old underground mine workings, and (2) subsidence over naturally ignited and burned underground coal beds. Major subsidence has taken place over old, underground workings near Beulah, Wilton, Lehigh, Haynes, and Belfield, and lesser subsidence near Scranton, and west and north of Bowman. Thickness of overburden above the coal in all these areas is believed to be less than 30 m (100 ft). Subsidence has not taken place over old underground workings along the Des Lacs and-Souris valleys northwest of Minot, where the thickness of overburden is more than 60 m (200 ft). Spectacular subsidence has occurred over a burning underground coal bed at Burning Coal Vein Park near the Little Missouri River, northwest of Amidon.

Application of Dempster-Shafer theory of evidence model to geoelectric and hydraulic parameters for groundwater potential zonation

NASA Astrophysics Data System (ADS)

Mogaji, Kehinde Anthony; Lim, Hwee San

2018-06-01

The application of a GIS - based Dempster - Shafer data driven model named as evidential belief function EBF- methodology to groundwater potential conditioning factors (GPCFs) derived from geophysical and hydrogeological data sets for assessing groundwater potentiality was presented in this study. The proposed method's efficacy in managing degree of uncertainty in spatial predictive models motivated this research. The method procedural approaches entail firstly, the database containing groundwater data records (bore wells location inventory, hydrogeological data record, etc.) and geophysical measurement data construction. From the database, different influencing groundwater occurrence factors, namely aquifer layer thickness, aquifer layer resistivity, overburden material resistivity, overburden material thickness, aquifer hydraulic conductivity and aquifer transmissivity were extracted and prepared. Further, the bore well location inventories were partitioned randomly into a ratio of 70% (19 wells) for model training and 30% (9 wells) for model testing. The synthesized of the GPCFs via applying the DS - EBF model algorithms produced the groundwater productivity potential index (GPPI) map which demarcated the area into low - medium, medium, medium - high and high potential zones. The analyzed percentage degree of uncertainty for the predicted lows potential zones classes and mediums/highs potential zones classes are >10% and <10%, respectively. The DS theory model-based GPPI map's validation through ROC approach established prediction rate accuracy of 88.8%. Successively, the determined transverse resistance (TR) values in the range of 1280 and 30,000 Ω my for the area geoelectrically delineated aquifer units of the predicted potential zones through Dar - Zarrouk Parameter analysis quantitatively confirm the DS theory modeling prediction results. This research results have expand the capability of DS - EBF model in predictive modeling by effective uncertainty

Evaluation of soil corrosivity and aquifer protective capacity using geoelectrical investigation in Bwari basement complex area, Abuja

NASA Astrophysics Data System (ADS)

Adeniji, A. E.; Omonona, O. V.; Obiora, D. N.; Chukudebelu, J. U.

2014-04-01

Bwari is one of the six municipal area councils of the Federal Capital Territory (FCT), Abuja with its attendant growing population and infrastructural developments. Groundwater is the main source of water supply in the area, and urbanization and industrialization are the predominant contributors of contaminants to the hydrological systems. In order to guarantee a continuous supply of potable water, there is a need to investigate the vulnerability of the aquifers to contaminants emanating from domestic and industrial wastes. A total of 20 vertical electrical soundings using Schlumberger electrode array with a maximum half current electrodes separation of 300 m was employed. The results show that the area is characterized by 3-6 geoelectric subsurface layers. The measured overburden thickness ranges from 1.0 to 24.3 m, with a mean value of 7.4 m. The resistivity and longitudinal conductance of the overburden units range from 18 to 11,908 Ωm and 0.047 to 0.875 mhos, respectively. Areas considered as high corrosivity are the central parts with ρ < 180 Ωm. The characteristic longitudinal unit conductance was used to classify the area into zones of good (0.7-4.49 mhos), moderate (0.2-0.69 mhos), weak (0.1-0.19 mhos), and poor (<0.1) aquifer protective capacity. Zones characterized by materials of moderate to good protective capacity serve as sealing potential for the underlying hydrogeological system in the area. This study is aimed at delineating zones that are very prone to groundwater contamination from surface contaminants and subsurface soils that are corrosive to utility pipes buried underground. Hence the findings of this work will constitute part of the tools for groundwater development and management and structural/infrastructural development planning of the area.

Basal hydraulic conditions of Ice Stream B

NASA Technical Reports Server (NTRS)

Engelhardt, Hermann; Kamb, Barclay

1993-01-01

Fifteen boreholes have been drilled to the base of Ice Stream B in the vicinity of UpB Camp. The boreholes are spread over an area of about 500 x 1000 m. Several till cores were retrieved from the bottom of the 1000-m-deep holes. Laboratory tests using a simple shear box revealed a yield strength of basal till of 2 kPa. This agrees well with in-situ measurements using a shear vane. Since the average basal shear stress of Ice Stream B with a surface slope of 0.1 degree is about 20 kPa, the ice stream cannot be supported by till that weak. Additional support for this conclusion comes from the basal water pressure that has been measured in all boreholes as soon as the hot water drill reached bottom. In several boreholes, the water pressure has been continuously monitored; in two of them, over several years. The water pressure varies but stays within 1 bar of flotation where ice overburden pressure and water pressure are equal. The ratio of water and overburden pressure lies between 0.986 and 1.002. This is an extremely high value as compared to other fast-moving ice masses; e.g., Variegated Glacier in surge has a ratio of 0.8, and Columbia Glacier - a fast-moving tidewater glacier - has a ratio of 0.9. It implies that water flow under the glacier occurs in a thin film and not in conduits that would drain away water too rapidly. It also implies that basal sliding must be very effective. Water flow under the glacier was measured in a salt-injection experiment where a salt pulse was released at the bottom of a borehole while 60 m down-glacier, the electrical resistance was measured between two other boreholes. A flow velocity of 7 mm/s was obtained.

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

Ethridge, F.G.; Saracino, A.M.; Burns, L.K.

The encompassing sandstones, siltstones, shales and thin conglomerates of the gasified G Coal seam at the North Knobs SDB-UCG site were deposited mainly in fluvial and poorly-drained swamp environments. These beds dip at 65/sup 0/ at the North Knobs site. Thin section and SEM analyses of the sandstones and coarse siltstones show that they are sublithic to subarkosic arenites cemented with clay minerals, calcite hematite, siderite and silica. The sandstones of Unit D directly above the coal seam have the highest concentration of calcite cement, the lowest mean grain size, and are best sorted in terms of quartz grain sizemore » variations; however, they are the worst sorted in terms of sieve size variations. Clay minerals in the sandstones are dominantly kaolinite and smectite with lesser amounts of illite and chlorite. These clays are of secondary origin. Heat alteration is present only in coals and overburden rock from cores that penetrated the cavity. Thermally altered rocks including hornfels, buchite, paralava rock and paralava breccia were found in the bottom of the dipping cavity near the injection well. The high temperature minerals of tridymite, cristobalite, mullite, cordierite, monoclinic pyroxene and high temperature plagioclase indicate that temperatures of at least 1200/sup 0/C to 1400/sup 0/C were attained in the lower part of the burn cavity. The mechanical test on the unaltered and altered overburden rock show that the most important lithologic property controlling rock strength and seismic wave velocity is the amount and type of cement in the rock. Other parameters measured were grain size, amount of clay cement, and porosity; sorting had a secondary effect on the rock strength and seismic wave velocity. There is a non-linear and direct relationship between mechanical strength and ultrasonic wave velocities for the rock tests. 30 references.« less

Compaction history of Upper Cretaceous shale (Al-Khod Formation) and its relationship to plate margin tectonics, Arabian Plate, Sultanate of Oman

NASA Astrophysics Data System (ADS)

AL-Sarmi, Musaab; Mattern, Frank; Scharf, Andreas; Pracejus, Bernhard; Al-Mamari, Amira; Al-Hinaai, Al-Shima

2017-04-01

Conglomerates of the late Cretaceous Al-Khod Formation have been intruded by older shale of the same formation along faults, which were opened/widened by extension, thus, resulting in shale dike formation. Following intrusion the shale was behaving plastically as its fissility follows the contact contours of the conglomeratic host rock and as stoped sandstone blocks are floating within the shale. Vertical calcite veins were ptygmatically folded with subhorizontal fold axial planes. All these aspects show that the shale contained a high water content in the beginning. The ptygmatically folded calcite veins display vertical shortening amounts of 40 % corresponding to 35 % to 45 % of water loss during compaction. Incalculable numbers of calcite veins of different orientations and thicknesses within the conglomerate along the shale contact indicate that the fluid was expelled from the shale into the conglomerate host rock under high pressure (overpressure?). Shale dyke formation took place after the late Cretaceous obduction of the Semail Ophiolite, before the deposition of early Tertiary carbonate rocks, and during the latest Cretaceous doming of the Saih Hatat area which was caused by deformation and slab breakoff, likely associated with gravitational collapse and elastic rebound. Shale intrusion was followed by deposition of 100 to 200 m thick sediments of the upper part of Al-Khod Formation, leading to compaction and water loss. The shale retained much of its water during the uppermost Cretaceous-late Paleocene stratigraphic hiatus as this interval is marked by erosion and a reduction of overburden, which was probably due to the elastic rebound. Folding of calcite veins together with a high amount of water loss was a consequence of compaction caused by the overburden of 1000 m thick shallow marine limestones which were deposited from the Eocene to Oligocene.

A parametric study on hydraulic conductivity and self-healing properties of geotextile clay liners used in landfills.

PubMed

Parastar, Fatemeh; Hejazi, Sayyed Mahdi; Sheikhzadeh, Mohammad; Alirezazadeh, Azam

2017-11-01

Nowadays, the raise of excessive generation of solid wastes is considered as a major environmental concern due to the fast global population growth. The contamination of groundwater from landfill leachate compromises every living creature. Geotextile clay liner (GCL) that has a sandwich structure with two fibrous sheets and a clay core can be considered as an engineered solution to prevent hazardous pollutants from entering into groundwater. The main objective of the present study is therefore to enhance the performance of GCL structures. By changing some structural factors such as clay type (sodium vs. calcium bentonite), areal density of clay, density of geotextile, geotextile thickness, texture type (woven vs. nonwoven), and needle punching density a series of GCL samples were fabricated. Water pressure, type of cover soil and overburden pressure were the environmental variables, while the response variables were hydraulic conductivity and self-healing rate of GCL. Rigid wall constant head permeability test was conducted on all the samples. The outlet water flow was measured and evaluated at a defined time period and the hydraulic conductivity was determined for each sample. In the final stage, self-healing properties of samples were investigated and an analytical model was used to explain the results. It was found that higher Montmorillonite content of clay, overburden pressure, needle punching density and areal density of clay poses better self-healing properties and less hydraulic conductivity, meanwhile, an increase in water pressure increases the hydraulic conductivity. Moreover, the observations were aligned with the analytical model and indicated that higher fiber inclusion as a result of higher needle-punching density produces closer contact between bentonite and fibers, reduces hydraulic conductivity and increases self-healing properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigation of guided wave propagation and attenuation in pipe buried in sand

NASA Astrophysics Data System (ADS)

Leinov, Eli; Lowe, Michael J. S.; Cawley, Peter

2015-07-01

Long-range guided wave testing is a well-established method for detection of corrosion defects in pipelines. The method is currently used routinely for above ground pipelines in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised and unpredictable due to attenuation of the guided wave resulting from energy leakage into the embedding soil. The attenuation characteristics of guided wave propagation in an 8 in. pipe buried in sand are investigated using a laboratory full-scale experimental rig and model predictions. We report measurements of attenuation of the T(0,1) and L(0,2) guided wave modes over a range of sand conditions, including loose, compacted, mechanically compacted, water saturated and drained. Attenuation values are found to be in the range of 1.65-5.5 dB/m and 0.98-3.2 dB/m for the torsional and longitudinal modes, respectively, over the frequency of 11-34 kHz. The application of overburden pressure modifies the compaction of the sand and increases the attenuation. Mechanical compaction of the sand yields similar attenuation values to those obtained with applied overburden pressure. The attenuation decreases in the fully water-saturated sand, and increases in drained sand to values comparable with those obtained for compacted sand. Attenuation measurements are compared with Disperse software model predictions and confirm that the attenuation phenomenon in buried pipes is essentially governed by the bulk shear velocity in the sand. The attenuation behaviour of the torsional guided wave mode is found not to be captured by a uniform soil model; comparison with predictions obtained with the Disperse software suggest that this is likely to be due to a layer of sand adhering to the surface of the pipe.

Modelling Cryovolcanism Due to Subsurface Ocean Freezing on Pluto and Charon

NASA Astrophysics Data System (ADS)

Conrad, J. W.; Nimmo, F.; Singer, K. N.

2016-12-01

The New Horizons spacecraft identified various possible cryovolcanic features on the surfaces of both Pluto and Charon [1]. However, there are major differences between the cryovolcanism on Pluto and Charon. Pluto has two mound-flanked depressions which are possibly cryovolcanic [2], while Charon's putative cryovolcanism is more widespread within its smooth southern plains. If Pluto or Charon have (or had) subsurface oceans, slow refreezing of these oceans would lead to extensional surface tectonics [3,4] and pressurization of the ocean [5]. Sufficiently large pressurization can overcome the overburden pressure and cause an eruption. We applied thermal evolution models based on [3] to determine likely freezing scenarios. Eruptions on Charon are possible under most conditions, and occur after tens of kilometers of freezing of an ice shell initially 100 km thick. This would produce an areal extensional strain of 1%. The implied globally-averaged thickness of erupted material is a few hundred meters and the critical crack width for propagation through the entire ice shell [6] is about half a meter for all eruption scenarios. Eruptions on Pluto require probably unrealistic freezing scenarios, because of the larger body size and higher overburden pressure. We conclude that ocean freezing is a possible source of cryovolcanism on Charon and may explain the smooth plains in its southern hemisphere [1]. Pluto, on the other hand, requires more complex models to explain the putative cryovolcanic features on its surface. [1] Moore et al., Science 351 (2016): 1284-1293. [2] Singer et al., LPSC 47 (2016): 2276 [3] Robuchon and Nimmo, Icarus 216 (2011): 426-439. [4] Hammond et al., GRL 43 (2016). [5] Manga and Wang, GRL 34 (2007). [6] Porco et al., The Astronomical Journal 148 (2014): 45.

Hydrodynamic code calculations of airblast for an explosive test in a shallow underground storage magazine

NASA Astrophysics Data System (ADS)

Kennedy, Lynn W.; Schneider, Kenneth D.

1990-07-01

A large-sclae test of the detonation of 20,000 kilograms of high explosive inside a shallow underground tunnel/chamber complex, simulating an ammunition storage magazine, was carried out in August, 1988, at the Naval Weapons Center, China Lake, California. The test was jointly sponsored by the U.S. Department of Defense Explosives Safety Board; the Safety Services Organisation of the Ministry of Defence, United Kingdom; and the Norwegian Defence Construction Service. The overall objective of the test was to determine the hazardous effects (debris, airblast, and ground motion) produced in this configuration. Actual storage magazines have considerably more overburden and are expected to contain and accidental detonation. The test configuration, on the other hand, was expected to rupture, and to scatter a significant amount of rocks, dirt and debris. Among the observations and measurements made in this test was study of airblast propagation within the storage chamber, in the access tunnel, and outside, on the tunnel ramp, prior to overburden venting. The results of these observations are being used to evaluate and validate current quantity-distance standards for the underground storage of munitions near inabited structures. As part of the prediction effort for this test, to assist with transducer ranging in the access tunnel and with post-test interpretation of the results, S-CUBED was asked to perform two-dimensional inviscid hydrodynamic code calculations of the explosive detonation and subsequent blastwave propagation in the interior chamber and access tunnel. This was accomplished using the S-CUBED Hydrodynamic Advanced Research Code (SHARC). In this paper, details of the calculations configuration will be presented. These will be compared to the actual as-built internal configuration of the tunnel/chamber complex. Results from the calculations, including contour plots and airblast waveforms, will be shown. The latter will be compared with experimental records

Mechanical stratification of autochthonous salt: Implications from basin-scale numerical models of rifted margin salt tectonics

NASA Astrophysics Data System (ADS)

Ings, Steven; Albertz, Markus

2014-05-01

Deformation of salt and sediments owing to the flow of weak evaporites is a common phenomenon in sedimentary basins worldwide, and the resulting structures and thermal regimes have a significant impact on hydrocarbon exploration. Evaporite sequences ('salt') of significant thickness (e.g., >1km) are typically deposited in many cycles of seawater inundation and evaporation in restricted basins resulting in layered autochthonous evaporite packages. However, analogue and numerical models of salt tectonics typically treat salt as a homogeneous viscous material, often with properties of halite, the weakest evaporite. In this study, we present results of two-dimensional plane-strain numerical experiments designed to illustrate the effects of variable evaporite viscosity and embedded frictional-plastic ('brittle') sediment layers on the style of salt flow and associated deformation of the sedimentary overburden. Evaporite viscosity is a first-order control on salt flow rate and the style of overburden deformation. Near-complete evacuation of low-viscosity salt occurs beneath expulsion basins, whereas significant salt is trapped when viscosity is high. Embedded frictional-plastic sediment layers (with finite yield strength) partition salt flow and develop transient contractional structures (folds, thrust faults, and folded faults) in a seaward salt-squeeze flow regime. Multiple internal sediment layers reduce the overall seaward salt flow during sediment aggradation, leaving more salt behind to be re-mobilized during subsequent progradation. This produces more seaward extensive allochthonous salt sheets. If there is a density difference between the embedded layers and the surrounding salt, then the embedded layers 'fractionate' during deformation and either float to the surface or sink to the bottom (depending on density), creating a thick zone of pure halite. Such a process of 'buoyancy fractionation' may partially explain the apparent paradox of layered salt in

Aquifer thermal-energy-storage modeling

NASA Astrophysics Data System (ADS)

Schaetzle, W. J.; Lecroy, J. E.

1982-09-01

A model aquifer was constructed to simulate the operation of a full size aquifer. Instrumentation to evaluate the water flow and thermal energy storage was installed in the system. Numerous runs injecting warm water into a preconditioned uniform aquifer were made. Energy recoveries were evaluated and agree with comparisons of other limited available data. The model aquifer is simulated in a swimming pool, 18 ft by 4 ft, which was filled with sand. Temperature probes were installed in the system. A 2 ft thick aquifer is confined by two layers of polyethylene. Both the aquifer and overburden are sand. Four well configurations are available. The system description and original tests, including energy recovery, are described.

Low-cost solar array structure development

NASA Astrophysics Data System (ADS)

Wilson, A. H.

1981-06-01

Early studies of flat-plate arrays have projected costs on the order of $50/square meter for installed array support structures. This report describes an optimized low-cost frame-truss structure that is estimated to cost below $25/square meter, including all markups, shipping an installation. The structure utilizes a planar frame made of members formed from light-gauge galvanized steel sheet and is supposed in the field by treated-wood trusses that are partially buried in trenches. The buried trusses use the overburden soil to carry uplift wind loads and thus to obviate reinforced-concrete foundations. Details of the concept, including design rationale, fabrication and assembly experience, structural testing and fabrication drawings are included.

LUNA: Nuclear astrophysics underground

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

Best, A.

Underground nuclear astrophysics with LUNA at the Laboratori Nazionali del Gran Sasso spans a history of 20 years. By using the rock overburden of the Gran Sasso mountain chain as a natural cosmic-ray shield very low signal rates compared to an experiment on the surface can be tolerated. The cross sectons of important astrophysical reactions directly in the stellar energy range have been successfully measured. In this proceeding we give an overview over the key accomplishments of the experiment and an outlook on its future with the expected addition of an additional accelerator to the underground facilities, enabling the coveragemore » of a wider energy range and the measurement of previously inaccessible reactions.« less

A nomogram for interpreting slope stability of fine-grained deposits in modern and ancient-marine environments.

USGS Publications Warehouse

Booth, J.S.; Sangrey, D.A.; Fugate, J.K.

1985-01-01

This nomogram was designed to aid in interpreting the causes of mass movement in modern and ancient settings, to provide a basis for evaluating and predicting slope stability under given conditions and to further the understanding of the relationships among the several key factors that control slope stability. Design of the nomogram is based on effective stress and combines consolidation theory as applicable to depositional environments with the infinite-slope model of slope-stability analysis. If infinite-slope conditions are assumed to exist, the effective overburden stress can be used to derive a factor of safety against static slope failure by using the angle of internal friction and the slope angle. -from Authors

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

Adamson, P.; Bishai, M.; Diwan, M. V.

We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. At the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. Conversely, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation thatmore » peaks in the winter.« less

Observation of seasonal variation of atmospheric multiple-muon events in the MINOS Near and Far Detectors

DOE PAGES

Adamson, P.; Bishai, M.; Diwan, M. V.; ...

2015-06-09

We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. At the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. Conversely, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation thatmore » peaks in the winter.« less

Preliminary report on the coal resources of the Dickenson area, Billings, Dunn, and Stark counties, North Dakota

USGS Publications Warehouse

Menge, Michael L.

1977-01-01

The Dickinson area is underlain by the coal-bearing Fort Union Formation (Paleocene). The Fort Union in this area contains nine potentially economic coal beds. Five of these beds are, either all or in part, shallow enough to be economically extracted by conventional strip-mining methods, while the remaining four deeper beds represent future possible strip-mining, in situ, or shaft-mining coal resources. The Fort Union coal beds in the Dickinson area are relatively flat lying (dips are less than 1??) and only slightly influenced by faulting and both depositional and post-depositional channeling. Topography, coal thickness, and minimum overburden all combine to give the Dickinson area an excellent future coal resource development potential.

Total number of longwall faces drops below 50

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

Fiscor, S.

2009-02-15

For the first time since Coal Age began its annual Longwall Census the number of faces has dropped below 50. A total of five mines operate two longwall faces. CONSOL Energy remains the leader with 12 faces. Arch Coal operates five longwall mines; Robert E. Murray owns five longwall mines. West Virginia has 13 longwalls, followed by Pennsylvania (8), Utah (6) and Alabama (6). A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries, depth of cut, model of equipment used (shearer, haulage system, roof support, facemore » conveyor, stage loader, crusher, electrical controls and voltage to face). 2 tabs., 1 photo.« less

Responding to the Medical Malpractice Insurance Crisis: A National Risk Management Information System

PubMed Central

Wess, Bernard P.; Jacobson, Gary

1987-01-01

In the process of forming a new medical malpractice reinsurance company, the authors analyzed thousands of medical malpractice cases, settlements, and verdicts. The evidence of those analyses indicated that the medical malpractice crisis is (1)emerging nation- and world-wide, (2)exacerbated by but not primarily a result of “predatory” legal action, (3)statistically determined by a small percentage of physicians and procedures, (4)overburdened with data but poor on information, (5)subject to classic forms of quality control and automation. The management information system developed to address this problem features a tiered data base architecture to accommodate medical, administrative, procedural, statistical, and actuarial analyses necessary to predict claims from untoward events, not merely to report them.

Correlation of Paleocene Harmon and Hansen lignite beds, Adams, Billings, Bowman, Golden Valley, Hettinger, and Slope Counties, Williston Basin, North Dakota

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

Keighin, C.W.; Flores, R.M.; Ochs, A.

In southwestern North Dakota, minable lignite beds in the Paleocene Fort Union Formation include the Harmon and Hansen beds in the Bowman-Gascoyne area. Data from more than 700 drill holes penetrating these beds was used to construct stratigraphic cross sections. The Harmon and Hansen beds are the thickest and most laterally persistent lignites found under < 150 ft of overburden. The Harmon coal bed is as much as 34 ft thick, and is often split by claystone interbeds of variable thickness. The Hansen coal bed typically occurs 10--100 ft below the Harmon coal bed; it rarely attains a thickness ofmore » 15 ft, and averages 4 ft in thickness.« less

Replacing revolving door: a collaborative approach to treating individuals in crisis.

PubMed

Lauer, Michelle; Brownstein, Rose

2008-06-01

The Crisis Assessment and Psychiatric Emergency Services (CAPES) unit was designed to improve the quality of psychiatric treatment, contain costs, and provide relief to overburdened psychiatric inpatient and emergency services in Delaware. This innovative program is the result of collaboration between public and private agencies to treat individuals in crisis. The myriad factors that contributed to a broken system and instigated Delaware's search for a solution are discussed in this article. The CAPES unit has resulted in improved communication among providers, decreased committal rates, better linkage to appropriate levels of care, increased safety, and improved coordination of services. Clinical implications for nursing practice include providing more holistic care in a safer environment.

Recent developments in the reclamation of surface mined lands

USGS Publications Warehouse

Sharma, K.D.; Gough, L.P.; Kumar, S.; Sharma, B.K.; Saxena, S.K.

1997-01-01

A broad review of mine land reclamation problems and challenges in arid lands is presented with special emphasis on work recently completed in India. The economics of mining in the Indian Desert is second only to agriculture in importance. Lands disturbed by mining, however, have only recently been the focus of reclamation attempts. Studies were made and results compiled of problems associated with germplasm selection, soil, plant and overburden characterization and manipulation, plant establishment methods utilized, soil amendment needs, use and conservation of available water and the evaluation of ecosystem sustainability. Emphasis is made of the need for multi-disciplinary approaches to mine land reclamation research and for the long-term monitoring of reclamation success.

Anomalous gold, antimony, arsenic, and tungsten in ground water and alluvium around disseminated gold deposits along the Getchell Trend, Humboldt County, Nevada

USGS Publications Warehouse

Grimes, D.J.; Ficklin, W.H.; Meier, A.L.; McHugh, J.B.

1995-01-01

Ground-water, alluvium, and bedrock samples were collected from drill holes near the Chimney Creek, Preble, Summer Camp, and Rabbit Creek disseminated gold deposits in northern Nevada. Results of chemical analyses of drill-hole water samples show the presence of hydromorphic dispersion anomalies of Au, As, Sb, and W in the local ground-water systems associated with these deposits. In addition, analysis of sequential dissolution and extraction solutions of drill cuttings of alluvium and bedrock indicate geochemical anomalies of gold and ore-related metals in the overburden at depths corresponding to the location of the present-day water table. This relationship suggests that water-rock reactions around these buried deposits are active. -from Authors

The overlooked terrestrial impacts of mountaintop mining

USGS Publications Warehouse

Wickham, James; Wood, Petra Bohall; Nicholson, Matthew C.; Jenkins, William; Druckenbrod, Daniel; Suter, Glenn W.; Strager, Michael P.; Mazzarella, Christine; Galloway, Walter; Amos, John

2013-01-01

Ecological research on mountaintop mining has been focused on aquatic impacts because the overburden (i.e., the mountaintop) is disposed of in nearby valleys, which leads to a wide range of water-quality impacts on streams. There are also numerous impacts on the terrestrial environment from mountaintop mining that have been largely overlooked, even though they are no less wide ranging, severe, and multifaceted. We review the impacts of mountaintop mining on the terrestrial environment by exploring six broad themes: (1) the loss of topographic complexity, (2) forest loss and fragmentation, (3) forest succession and soil loss, (4) forest loss and carbon sequestration, (5) biodiversity, and (6) human health and well-being.

Low-cost solar array structure development

NASA Technical Reports Server (NTRS)

Wilson, A. H.

1981-01-01

Early studies of flat-plate arrays have projected costs on the order of $50/square meter for installed array support structures. This report describes an optimized low-cost frame-truss structure that is estimated to cost below $25/square meter, including all markups, shipping an installation. The structure utilizes a planar frame made of members formed from light-gauge galvanized steel sheet and is supposed in the field by treated-wood trusses that are partially buried in trenches. The buried trusses use the overburden soil to carry uplift wind loads and thus to obviate reinforced-concrete foundations. Details of the concept, including design rationale, fabrication and assembly experience, structural testing and fabrication drawings are included.

Method for Location of An External Dump in Surface Mining Using the A-Star Algorithm

NASA Astrophysics Data System (ADS)

Zajączkowski, Maciej; Kasztelewicz, Zbigniew; Sikora, Mateusz

2014-10-01

The construction of a surface mine always involves the necessity of accessing deposits through the removal of the residual overburden above. In the beginning phase of exploitation, the masses of overburden are located outside the perimeters of the excavation site, on the external dump, until the moment of internal dumping. In the case of lignite surface mines, these dumps can cover a ground surface of several dozen to a few thousand hectares. This results from a high concentration of lignite extraction, counted in millions of Mg per year, and the relatively large depth of its residual deposits. Determining the best place for the location of an external dump requires a detailed analysis of existing options, followed by a choice of the most favorable one. This article, using the case study of an open-cast lignite mine, presents the selection method for an external dump location based on graph theory and the A-star algorithm. This algorithm, based on the spatial distribution of individual intersections on the graph, seeks specified graph states, continually expanding them with additional elementary fields until the required surface area for the external dump - defined by the lowest value of the occupied site - is achieved. To do this, it is necessary to accurately identify the factors affecting the choice of dump location. On such a basis, it is then possible to specify the target function, which reflects the individual costs of dump construction on a given site. This is discussed further in chapter 3. The area of potential dump location has been divided into elementary fields, each represented by a corresponding geometrical locus. Ascribed to this locus, in addition to its geodesic coordinates, are the appropriate attributes reflecting the degree of development of its elementary field. These tasks can be carried out automatically thanks to the integration of the method with the system of geospatial data management for the given area. The collection of loci, together

Current oil and gas production from North American Upper Cretaceous chalks

USGS Publications Warehouse

Scholle, Peter A.

1977-01-01

Production of oil and natural gas from North American chalks has increased significantly during the past five years, spurred by the prolific production from North Sea chalks, as well as by higher prices and improved production technology. Chalk reservoirs have been discovered in the Gulf Coast in the Austin Group, Saratoga and Annona Chalks, Ozan Formation, Selma Group, Monroe gas rock (an informal unit of Navarro age), and other Upper Cretaceous units. In the Western Interior, production has been obtained from the Cretaceous Niobrara and Greenhorn Formations. Significant, though subcommercial, discoveries of natural gas and gas condensate also have been made in the Upper Cretaceous Wyandot Formation on the Scotian Shelf of eastern Canada. All North American chalk units share a similar depositional and diagenetic history. The chalks consist primarily of whole and fragmented coccoliths with subordinate planktonic and benthonic Foraminifera, inoceramid prisms, oysters, and other skeletal grains. Most have between 10 and 35 percent HCl-insoluble residue, predominantly clay. Deposition was principally below wave base in tens to hundreds of meters of water. The diagenetic history of a chalk is critical in determining its reservoir potential. All chalk has a stable composition (low-Mg calcite) and very high primary porosity. With subsequent burial, mechanical and chemical (solution-transfer) compaction can reduce or completely eliminate pore space. The degree of loss of primary porosity in chalk sections is normally a direct function of the maximum depth to which it has been buried. Pore-water chemistry, pore-fluid pressures, and tectonic stresses also influence rates of cementation. Oil or gas reservoirs of North American chalk fall into three main groups: 1. Areas with thin overburden and significant primary porosity retention (for example, Niobrara Formation of Kansas and eastern Colorado). 2. Areas with thicker overburden but considerable fracturing. Here primary

The structural geometry and development of the central Appalachian fold-and thrust belt across the Pennsylvania salient: The effects of syntectonic loading

NASA Astrophysics Data System (ADS)

Evans, Mark

2017-04-01

anticline structure, as well as those structures toward the hinterland, restore to a nearly straight fault traces oriented 045°-050°. The relatively straight restored faults require a rigid indenter colliding from the southeast to impose the curvature to the salient. The regional variation in structural style and ramp spacing may be related to the distribution of Late Carboniferous to Permian syn-tectonic loads during thrusting. Paleo-overburden thicknesses were determined from fluid inclusion microthermometry data of CH4±CO2 and aqueous fluid inclusions from syn-tectonic veins. In general, on the retrodeformed sections, restored overburdens are typically less above anticlinoria (<1.5 to 4.0 km), while much larger (4.3 to 6.1 km) above synclinoria. This suggests that syn-tectonic loading in the synclinoria due to sedimentation and/or overthrusting increased pore-fluid pressure enabling forelandward transport. Areas with less syntectonic overburden were prone to develop high-amplitude fold structures.

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

Not Available

This is a report on geologic and hydrologic investigations of the former Municipal Landfill, Middlesex, New Jersey, conducted during 1982 and 1983 by Bechtel National, Inc. for the United States Department of Energy, Oak Ridge Operations Office. The investigations were designed to assess the feasibility of stabilizing the radioactive contamination present on site. The investigations were conducted in two phases: Phase 1 consisted of permeability tests; Phase 2 consisted of tests to ascertain the extent of hydraulic interconnection between various stratigraphic units. The investigations revealed that a complete separation of bedrock and overburden did not exist and that the claymore » present could not be relied upon to confine vertical migration of contaminants over the long term. 6 references, 27 figures, 6 tables.« less

Seasonal variation of the underground cosmic muon flux observed at Daya Bay

NASA Astrophysics Data System (ADS)

An, F. P.; Balantekin, A. B.; Band, H. R.; Bishai, M.; Blyth, S.; Cao, D.; Cao, G. F.; Cao, J.; Chan, Y. L.; Chang, J. F.; Chang, Y.; Chen, H. S.; Chen, Q. Y.; Chen, S. M.; Chen, Y. X.; Chen, Y.; Cheng, J.; Cheng, Z. K.; Cherwinka, J. J.; Chu, M. C.; Chukanov, A.; Cummings, J. P.; Ding, Y. Y.; Diwan, M. V.; Dolgareva, M.; Dove, J.; Dwyer, D. A.; Edwards, W. R.; Gill, R.; Gonchar, M.; Gong, G. H.; Gong, H.; Grassi, M.; Gu, W. Q.; Guo, L.; Guo, X. H.; Guo, Y. H.; Guo, Z.; Hackenburg, R. W.; Hans, S.; He, M.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Hsiung, Y. B.; Hu, B. Z.; Hu, T.; Huang, E. C.; Huang, H. X.; Huang, X. T.; Huber, P.; Huo, W.; Hussain, G.; Jaffe, D. E.; Jen, K. L.; Jetter, S.; Ji, X. P.; Ji, X. L.; Jiao, J. B.; Johnson, R. A.; Jones, D.; Kang, L.; Kettell, S. H.; Khan, A.; Kohn, S.; Kramer, M.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Langford, T. J.; Lau, K.; Lebanowski, L.; Lee, J.; Lee, J. H. C.; Lei, R. T.; Leitner, R.; Li, C.; Li, D. J.; Li, F.; Li, G. S.; Li, Q. J.; Li, S.; Li, S. C.; Li, W. D.; Li, X. N.; Li, X. Q.; Li, Y. F.; Li, Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, S.; Lin, S. K.; Lin, Y.-C.; Ling, J. J.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, J. L.; Liu, J. C.; Loh, C. W.; Lu, C.; Lu, H. Q.; Lu, J. S.; Luk, K. B.; Ma, X. Y.; Ma, X. B.; Ma, Y. Q.; Malyshkin, Y.; Martinez Caicedo, D. A.; McDonald, K. T.; McKeown, R. D.; Mitchell, I.; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Ngai, H. Y.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Pan, H.-R.; Park, J.; Patton, S.; Pec, V.; Peng, J. C.; Pinsky, L.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Qiu, R. M.; Raper, N.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Sebastiani, C.; Steiner, H.; Sun, J. L.; Tang, W.; Taychenachev, D.; Treskov, K.; Tsang, K. V.; Tull, C. E.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C. H.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, W.; Wang, X.; Wang, Y. F.; Wang, Z.; Wang, Z.; Wang, Z. M.; Wei, H. Y.; Wen, L. J.; Whisnant, K.; White, C. G.; Whitehead, L.; Wise, T.; Wong, H. L. H.; Wong, S. C. F.; Worcester, E.; Wu, C.-H.; Wu, Q.; Wu, W. J.; Xia, D. M.; Xia, J. K.; Xing, Z. Z.; Xu, J. L.; Xu, Y.; Xue, T.; Yang, C. G.; Yang, H.; Yang, L.; Yang, M. S.; Yang, M. T.; Yang, Y. Z.; Ye, M.; Ye, Z.; Yeh, M.; Young, B. L.; Yu, Z. Y.; Zeng, S.; Zhan, L.; Zhang, C.; Zhang, C. C.; Zhang, H. H.; Zhang, J. W.; Zhang, Q. M.; Zhang, X. T.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Y. M.; Zhang, Z. J.; Zhang, Z. Y.; Zhang, Z. P.; Zhao, J.; Zhou, L.; Zhuang, H. L.; Zou, J. H.

2018-01-01

The Daya Bay Experiment consists of eight identically designed detectors located in three underground experimental halls named as EH1, EH2, EH3, with 250, 265 and 860 meters of water equivalent vertical overburden, respectively. Cosmic muon events have been recorded over a two-year period. The underground muon rate is observed to be positively correlated with the effective atmospheric temperature and to follow a seasonal modulation pattern. The correlation coefficient α, describing how a variation in the muon rate relates to a variation in the effective atmospheric temperature, is found to be αEH1 = 0.362±0.031, αEH2 = 0.433±0.038 and αEH3 = 0.641±0.057 for each experimental hall.

Coal rib response during bench mining: A case study

PubMed Central

Sears, Morgan M.; Rusnak, John; Van Dyke, Mark; Rashed, Gamal; Mohamed, Khaled; Sloan, Michael

2018-01-01

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United States. Over the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in U.S. underground coal mines. Nine of these 12 fatalities (75%) have occurred in room-and-pillar mines. The objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 m. This paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site. PMID:29862125

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

Adamson, P.

We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. Thus, at the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. In contrast and unexpectedly, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit amore » seasonal rate modulation that peaks in the winter.« less

The ANDES Deep Underground Laboratory in South America: status and prospects

NASA Astrophysics Data System (ADS)

Bertou, Xavier

2017-01-01

The construction of the Agua Negra tunnel through the Andes between Argentina and Chile is a unique opportunity to build a world class deep underground laboratory in the southern hemisphere, with 1750 m of rock overburden. At 30 degrees latitude south, far from nuclear power plants, it provides a unique site for Dark Matter searches and Neutrino experiments, and can host multidisciplinary experiments with a specific focus on Earth sciences given its location in a peculiar geoactive region. Its operation is foreseen to be coordinated by an international consortium and to start in 2026. In this presentation the current status of the Agua Negra tunnel and the ANDES initiative will be reviewed, and the scientific programme of the planned laboratory will be discussed.

Coal companies invest in more longwall capacity

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

Fiscor, S.

2006-02-15

This year's annual survey shows not much has changed since last year. The overall population stands at 47 mines operating 53 longwalls. CONSOL Energy remains the leading US longwall operator with 13 installations, followed by Arch Coal (5), Robert E. Murray (5) and Massey Energy (4). West Virginia remains the leading longwall mining state with 14 faces in 2005, followed by Pennsylvania (8), Alabama (7), Utah (7) and Colorado (5). A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries, depth of cut, model of equipment usedmore » (shearer, haulage system, roof support, face conveyor, stage loader, crusher, electrical controls and voltage to face). 1 photos., 2 tabs.« less

Stress history and geotechnical properties of sediment from the Cape Fear Diapir, Blake Ridge Diapir, and Blake Ridge

USGS Publications Warehouse

Winters, W.J.

2000-01-01

Geotechnical properties of sediment from Ocean Drilling Program Leg 164 are presented as: (1) normalized shipboard strength ratios from the Cape Fear Diapir, the Blake Ridge Diapir, and the Blake Ridge; and (2) Atterberg limit, vane shear strength, pocket-penetrometer strength, and constant-rate-of-strain consolidation results from Hole 995A, located on the Blake Ridge. This study was conducted to understand the stress history in a region characterized by high sedimentation rates and the presence of gas hydrates. Collectively, the results indicate that sediment from the Blake Ridge exhibits significant underconsolidated behavior, except near the seafloor. At least 10 m of additional overburden was removed by erosion or mass wasting at Hole 993A on the Cape Fear Diapir, compared to nearby sites.

Health Information Technology as a Universal Donor to Bioethics Education.

PubMed

Goodman, Kenneth W

2017-04-01

Health information technology, sometimes called biomedical informatics, is the use of computers and networks in the health professions. This technology has become widespread, from electronic health records to decision support tools to patient access through personal health records. These computational and information-based tools have engendered their own ethics literature and now present an opportunity to shape the standard medical and nursing ethics curricula. It is suggested that each of four core components in the professional education of clinicians-privacy, end-of-life care, access to healthcare and valid consent, and clinician-patient communication-offers an opportunity to leverage health information technology for curricular improvement. Using informatics in ethics education freshens ethics pedagogy and increases its utility, and does so without additional demands on overburdened curricula.

Regelation and ice segregation

NASA Technical Reports Server (NTRS)

Miller, Robert D.

1988-01-01

Macroscopic processes can have an important effect on the state of regolith water. The two primary mechanisms responsible for the formation of segregated ice on Earth, thermally induced regelation and hydraulic fracturing, are reviewed while their potential importance on Mars is examined. While regelation is the dominant terrestrial process, it requires a warmer and wetter environment than currently exists on Mars. In this respect, the conditions required for hydraulic fracturing are less demanding. In assessing its potential importance on Mars, it is noted that hydraulic fracturing can produce a localized zone of high pressure water that could readily disrupt an overburden of frozen ground. Such a process, it is concluded, may have triggered the release of groundwater that led to the formation of the major outflow channels.

Controlling and assessing pressure conditions during treatment of tar sands formations

DOEpatents

Zhang, Etuan; Beer, Gary Lee

2015-11-10

A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the tar sands formation from a plurality of heaters located in the formation. Heat is allowed to transfer from the heaters to at least a portion of the formation. A pressure in the portion of the formation is controlled such that the pressure remains below a fracture pressure of the formation overburden while allowing the portion of the formation to heat to a selected average temperature of at least about 280.degree. C. and at most about 300.degree. C. The pressure in the portion of the formation is reduced to a selected pressure after the portion of the formation reaches the selected average temperature.

Complex solution of problem of all-season construction of roads and pipelines on universal composite pontoon units

NASA Astrophysics Data System (ADS)

Ryabkov, A. V.; Stafeeva, N. A.; Ivanov, V. A.; Zakuraev, A. F.

2018-05-01

A complex construction consisting of a universal floating pontoon road for laying pipelines in automatic mode on its body all year round and in any weather for Siberia and the Far North has been designed. A new method is proposed for the construction of pipelines on pontoon modules, which are made of composite materials. Pontoons made of composite materials for bedding pipelines with track-forming guides for automated wheeled transport, pipelayer, are designed. The proposed system eliminates the construction of a road along the route, ensures the buoyancy and smoothness of the self-propelled automated stacker in the form of a "centipede", which has a number of significant advantages in the construction and operation of the entire complex in the swamp and watered areas without overburden.

Spiced-up ANFO mixture leads to super blasts for casting

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

Chironis, N.P.

1984-05-01

There is one problem common to many coal operators in the mountainous regions of western Pennsylvania. As coal seams nearer the crop lines of their mine sites are removed, the overburden heights and stripping ratios increase to about 20-to-1, the range where coal becomes uneconomical to mine. Faced with this situation, a mine operator usually pursues one of four options: 1. Drive a drift mine, which means switching to underground operations with all the complexity and costs involved; 2. Purchase a larger dragline, which involves huge capital expenditures; 3. Bring in an augering machine to auger the exposed seams, amore » technique effective only for a very limited distance into the highwalls; 4. Discontinue operations, the route most operators take.« less

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.

Elastic and viscoelastic model of the stress history of sedimentary rocks

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

Warpinski, N.R.

A model has been developed to calculate the elastic and viscoelastic stresses which develop in rocks at depth due to burial, uplift and diagenesis. This model includes the effect of the overburden load, tectonic or geometric strains, thermal strains, varying material properties, pore pressure variations, and viscoeleastic relaxation. Calculations for some simple examples are given to show the contributions of the individual stress components due to gravity, tectonics, thermal effects and pore pressure. A complete stress history for Mesaverde rocks in the Piceance basin is calculated based on available burial history, thermal history and expected pore pressure, material property andmore » tectonic strain variations through time. These calculations show the importance of including material property changes and viscoelastic effects. 15 refs., 48 figs.« less

Numerical Simulation and Monitoring of Surface Environment Influence of Waterless Sand Layer Shield Tunneling

NASA Astrophysics Data System (ADS)

Shang, Yanliang; Han, Tongyin; Shi, Wenjun; Du, Shouji; Qin, Zhichao

2017-10-01

The development of urban subway is becoming more and more rapid and plays an increasingly important role. The shield tunneling method has become the first choice for the construction of urban subway tunnel in the construction of urban subway. The paper takes the interval of Shijiazhuang Metro Line 3 Administrative Center Station and Garden Park Station as the engineering background. The establishment of double shield finite difference model by considering the thickness of covering soil, tunnel excavation and excavation at the same time, distance and other factors, the surface deformation, and soil thickness. The ground deformation law is obtained, the surface settlement is inversely proportional to the overburden thickness and the double line spacing, and the gradual excavation is smaller than the synchronous excavation.

A case for the expansion of day surgery.

PubMed

Ogg, T; Heath, P; Brownlie, G

1989-12-01

The efficiency of the National Health Service (NHS) is currently under scrutiny and the problems faced by the surgical services include a shortage of financial resources, fewer beds, poor nursing recruitment and rising waiting lists. During 1984-1988 a purpose built, separate 12-bedded day surgery unit at Addenbrooke's Hospital, Cambridge operated upon 13,000 patients, with a readmission rate of less than 1%. Senior medical staff are involved and the overall surgical waiting list has been reduced by 40.9%. Nurse recruitment has been excellent, and the community medical and nursing services have not been overburdened. The results detailed in this paper suggest that day surgery deserves special consideration as one acceptable solution to some of the current NHS problems.

Studies on a middle Pennsylvanian compression-impression flora from the overburden of the Herrin (No. 6) coal at Carterville, Illinois

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

Gastaldo, R.A.

Titles and authors of Ph.D dissertations and M.S. theses are listed as completed or near completion in the following areas of study related to coal: botany (10), chemistry (10), community development (1), economics (1), electrical science and systems engineering (1), forestry (7), geography (2), geology (23), health education (2), mathematics (1), zoology (24), mining engineering (9), plant and soil science (4), political science (2), and thermal and environmental engineering (3).

Geology and evolution of lakes in north-central Florida

USGS Publications Warehouse

Kindinger, J.L.; Davis, J.B.; Flocks, J.G.

1999-01-01

Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phases: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase (mature); and (4) polje (drowned prairie) - broad flat-bottom that have one or all phases of sinkhole. Using these criteria, Florida lakes can be classified by size, fill, subsurface features, and geomorphology.Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phased: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase

Spatial analysis for susceptibility of second-time karst sinkholes: A case study of Jili Village in Guangxi, China

NASA Astrophysics Data System (ADS)

Zhou, Guoqing; Yan, Hongbo; Chen, Kunhua; Zhang, Rongting

2016-04-01

After a big karst sinkhole happened in Jili Village of Guangxi, China, the local government was eager to quantitatively analyze and map susceptible areas of the potential second-time karst sinkholes in order to make timely decisions whether the residents living in the first-time sinkhole areas should move. For this reason, karst sinkholes susceptibility geospatial analysis is investigated using multivariate spatial data, logistic regression model (LRM) and Geographical Information System (GIS). Ten major karst sinkholes related factors, including (1) formation lithology, (2) soil structure, (3) profile curvature, (4) groundwater depth, (5) fluctuation of groundwater level, (6) percolation rate of soil, (7) degree of karst development, (8) distance from fault, (9) distance from the traffic route, and (10) overburden thickness were selected, and then each of factors was classified and quantitated with the three or four levels. The LRM was applied to evaluate which factor makes significant contributions to sinkhole. The results demonstrated that formation lithology, soil structure, profile curvature, groundwater depth, ground water level, percolation rate of soil, and degree of karst development, the distance from fault, and overburden thickness are positive, while one factor, the distance from traffic routes is negative, which is deleted from LRM model. The susceptibility of the potential sinkholes in the study area is estimated and mapped using the solved impact factors. The susceptible degrees of the study area are classified into five levels, very high, high, moderate, low, and ignore susceptibility. It has been found that that both very high and high susceptibility areas are along Datou Hill and the foothills of the study area. This finding is verified by field observations. With the investigations conducted in this paper, it can be concluded that the susceptibility maps produced in this paper are reliable and accurate, and useful as a reference for local

Development of monitoring techniques for potential seepage of CO2 from sub-seafloor storage sites: Field studies at Sleipner, North Sea

NASA Astrophysics Data System (ADS)

James, R. H.; Connelly, D. P.; Bull, J. M.; Lichtschlag, A.; Cevatoglu, M.; Le Bas, T.; Wright, I. C.

2012-12-01

Although CO2 has been stored at the Sleipner site in the North Sea for over 15 years, and a number of other sub-seafloor storage sites are now either in operation or planned, almost nothing is known about the effect of potential seepage on marine ecosystems. To address this, we will undertake a comprehensive field campaign to Sleipner (RRS James Cook Cruise 77) in September 2012 that aims to: (i) Constrain the potential pathways of seepage from the storage site. (ii) Test methods for the detection of seepage, including formation fluids, natural gas and CO2, as it passes through the sedimentary overburden and into the water column. (iii) Develop a monitoring strategy suitable for all offshore carbon capture and storage projects. To this end, we will conduct an extensive AUV survey in the vicinity of the sub-seafloor CO2 plume, using our novel, long-range AUTOSUB system. AUTOSUB will be equipped with a variety of instrumentation, including sidescan sonar and an EM2000 multibeam systems, as well as a CHIRP profiler capable of inspecting the architecture of the sedimentary overburden at unprecedented spatial resolution. Other instrumentation will include a series of sensors (including a pH sensor), to detect and monitor the dispersion of potential seepage, and a new colour camera. Areas of interest, revealed by the AUV surveys, will be inspected and sampled using a hybrid remotely operated vehicle, equipped with high resolution video cameras, a grab sampling device, and instrumentation for the collection of precisely-located water samples. Further water samples will be collected using the ship-based CTD system. Fluid and gas seeps will be sampled using a vibrocoring system, and analyses of the porefluid chemistry will be used to quantify fluxes across the sediment-seawater interface, and the source, transformation, and fate of dissolved constituents. Longer-term monitoring will be addressed by deployment of a seafloor lander, that is equipped with a flow meter, a

Theory of reflectivity blurring in seismic depth imaging

NASA Astrophysics Data System (ADS)

Thomson, C. J.; Kitchenside, P. W.; Fletcher, R. P.

2016-05-01

A subsurface extended image gather obtained during controlled-source depth imaging yields a blurred kernel of an interface reflection operator. This reflectivity kernel or reflection function is comprised of the interface plane-wave reflection coefficients and so, in principle, the gather contains amplitude versus offset or angle information. We present a modelling theory for extended image gathers that accounts for variable illumination and blurring, under the assumption of a good migration-velocity model. The method involves forward modelling as well as migration or back propagation so as to define a receiver-side blurring function, which contains the effects of the detector array for a given shot. Composition with the modelled incident wave and summation over shots then yields an overall blurring function that relates the reflectivity to the extended image gather obtained from field data. The spatial evolution or instability of blurring functions is a key concept and there is generally not just spatial blurring in the apparent reflectivity, but also slowness or angle blurring. Gridded blurring functions can be estimated with, for example, a reverse-time migration modelling engine. A calibration step is required to account for ad hoc band limitedness in the modelling and the method also exploits blurring-function reciprocity. To demonstrate the concepts, we show numerical examples of various quantities using the well-known SIGSBEE test model and a simple salt-body overburden model, both for 2-D. The moderately strong slowness/angle blurring in the latter model suggests that the effect on amplitude versus offset or angle analysis should be considered in more realistic structures. Although the description and examples are for 2-D, the extension to 3-D is conceptually straightforward. The computational cost of overall blurring functions implies their targeted use for the foreseeable future, for example, in reservoir characterization. The description is for scalar

Characterization of Athabasca lean oil sands and mixed surficial materials: Comparison of capillary electrophoresis/low-resolution mass spectrometry and high-resolution mass spectrometry.

PubMed

MacLennan, Matthew S; Peru, Kerry M; Swyngedouw, Chris; Fleming, Ian; Chen, David D Y; Headley, John V

2018-05-15

Oil sands mining in Alberta, Canada, requires removal and stockpiling of considerable volumes of near-surface overburden material. This overburden includes lean oil sands (LOS) which cannot be processed economically but contain sparingly soluble petroleum hydrocarbons and naphthenic acids, which can leach into environmental waters. In order to measure and track the leaching of dissolved constituents and distinguish industrially derived organics from naturally occurring organics in local waters, practical methods were developed for characterizing multiple sources of contaminated water leakage. Capillary electrophoresis/positive-ion electrospray ionization low-resolution time-of-flight mass spectrometry (CE/LRMS), high-resolution negative-ion electrospray ionization Orbitrap mass spectrometry (HRMS) and conventional gas chromatography/flame ionization detection (GC/FID) were used to characterize porewater samples collected from within Athabasca LOS and mixed surficial materials. GC/FID was used to measure total petroleum hydrocarbon and HRMS was used to measure total naphthenic acid fraction components (NAFCs). HRMS and CE/LRMS were used to characterize samples according to source. The amounts of total petroleum hydrocarbon in each sample as measured by GC/FID ranged from 0.1 to 15.1 mg/L while the amounts of NAFCs as measured by HRMS ranged from 5.3 to 82.3 mg/L. Factors analysis (FA) on HRMS data visually demonstrated clustering according to sample source and was correlated to molecular formula. LRMS coupled to capillary electrophoresis separation (CE/LRMS) provides important information on NAFC isomers by adding analyte migration time data to m/z and peak intensity. Differences in measured amounts of total petroleum hydrocarbons by GC/FID and NAFCs by HRMS indicate that the two methods provide complementary information about the nature of dissolved organic species in a soil or water leachate samples. NAFC molecule class O x S y is a possible tracer for LOS

Endurance, resistance and resilience in the South African health care system: case studies to demonstrate mechanisms of coping within a constrained system.

PubMed

Eyles, John; Harris, Bronwyn; Fried, Jana; Govender, Veloshnee; Munyewende, Pascalia

2015-09-29

South Africa is at present undertaking a series of reforms to transform public health services to make them more effective and responsive to patient and provider needs. A key focus of these reforms is primary care and its overburdened, somewhat dysfunctional and hierarchical nature. This comparative case study examines how patients and providers respond in this system and cope with its systemic demands through mechanisms of endurance, resistance and resilience, using coping and agency literatures as the theoretical lenses. As part of a larger research project carried out between 2009 and 2010, this study conducted semi-structured interviews and observations at health facilities in three South African provinces. This study explored patient experiences of access to health care, in particular, ways of coping and how health care providers cope with the health care system's realities. From this interpretive base, four cases (two patients, two providers) were selected as they best informed on endurance, resistance and resilience. Some commentary from other respondents is added to underline the more ubiquitous nature of these coping mechanisms. The cases of four individuals highlight the complexity of different forms of endurance and passivity, emotion- and problem-based coping with health care interactions in an overburdened, under-resourced and, in some instances, poorly managed system. Patients' narratives show the micro-practices they use to cope with their treatment, by not recognizing victimhood and sometimes practising unhealthy behaviours. Providers indicate how they cope in their work situations by using peer support and becoming knowledgeable in providing good service. Resistance and resilience narratives show the adaptive power of individuals in dealing with difficult illness, circumstances or treatment settings. They permit individuals to do more than endure (itself a coping mechanism) their circumstances, though resistance and resilience may be limited. These

Compressional velocities from multichannel refraction arrivals on Georges Bank: northwest Atlantic Ocean

USGS Publications Warehouse

McGinnis, L. D.; Otis, R. M.

1979-01-01

Velocities were obtained from unreversed, refracted arrivals on analog records from a 48‐channel, 3.6-km hydrophone cable (3.89 km from the airgun array to the last hydrophone array). Approximately 200 records were analyzed along 1500 km of ship track on Georges Bank, northwest Atlantic Ocean, to obtain regional sediment velocity distribution to a depth of 1.4 km below sea level. This technique provides nearly continuous coverage of refraction velocities and vertical velocity gradients. Because of the length of the hydrophone cable and the vertical velocity gradients, the technique is applicable only to the Continental Shelf and the shallower parts of the Continental Slope in water depths less than 300 m. Sediment diagenesis, the influence of overburden pressure on compaction, lithology, density, and porosity are inferred from these data. Velocities of the sediment near the water‐sediment interface range from less than 1500 m/sec on the north edge of Georges Bank to 1830 m/sec for glacial deposits in the northcentral part of the bank. Velocity gradients in the upper 400 m range from 1.0km/sec/km(sec−1) on the south edge of the bank to 1.7sec−1 on the north. Minimum gradients of 0.8sec−1 were observed south of Nantucket Island. Velocities and velocity gradients are explained in relation to physical properties of the Cretaceous, Tertiary, and Pleistocene sediments. Isovelocity contours at 100-m/sec intervals are nearly horizontal in the upper 400 m. Isovelocity contours at greater depths show a greater difference from a mean depth because of the greater structural and lithological variation. Bottom densities inferred from the velocities range from 1.7 to 1.9g/cm3 and porosities range from 48 to 62 percent. The most significant factor controlling velocity distribution on Georges Bank is overburden pressure and resulting compaction. From the velocity data we conclude that Georges Bank has been partially overridden by a continental ice sheet.

Geophysical Investigation of Buried Slag at the Parrot Tailings Site, Butte, Montana

NASA Astrophysics Data System (ADS)

Ha, C. D. M.; Shepherd, K.; Mack, A.; Rutherford, B. S.; Speece, M. A.

2016-12-01

Butte, Montana, has served as an important mining district for more than 120 years. This area contains historic mine waste from decades of unregulated mining practices. In July 1881, the Parrot smelter in Butte started operations and was soon processing ore and producing copper. The Parrot smelter also had a concentrating plant that treated the ore prior to smelting. The Parrot smelter wastes (slag and tailings) were later covered with Berkeley Pit crushed quartz monzonite overburden. The slag is bricked because it was deposited hot and, as a consequence forms a laterally extensive, cohesive, hard body that is difficult to remove without blasting. With the mine waste being covered by unknown quantities of overburden and soil throughout the area, and core data being limited and expensive to retrieve, the only economical method of discovery is geophysics. Several geophysical techniques were used to determine the lateral boundaries and depth of the buried slag body. The geophysical methods used were seismic, gravity, electromagnetic induction, and magnetics. Not all of these geophysical surveys produced useful results due to the nature of the slag. For instance, electromagnetic induction could not distinguish between the slag and adjacent tailings; and, the microgravity profiles showed only a small gravitational field variation caused by the density contrast between slag and the surrounding tailings, sediment and granitic cover. On the other hand, the seismic surveys resulted in unexpected first arrival times that distinctly showed velocity variations due to the slag. In addition, the slag body produced a large magnetic response. Unpublished, proprietary well data allowed us to model the slag body from our magnetic data. This model was confirmed by projecting velocity tomograms, that we created using seismic diving waves, onto our magnetic models. Model results were combined to form a three-dimensional image of the slag body. These results will be used to help

The promise of precise borehole gravimetry in petroleum exploration and exploitation

USGS Publications Warehouse

McCulloh, Thane Hubert

1966-01-01

, but extraction costs are prohibitive where overburden is thick. High-grade dolomite with relatively thin overburden is found in eastern Winnebago County and southwestern Boone County. (Author 's abstract)

Salt tectonics in an experimental turbiditic tank

NASA Astrophysics Data System (ADS)

Sellier, Nicolas; Vendeville, Bruno

2010-05-01

We modelled the effect of the deposition of clastic sediments wedges along passive margin by combining two different experimental approaches. The first approach, which uses flume experiments in order to model turbiditic transport and deposition, had focused, so far mainly on the stratigraphic architecture and flow properties. But most experiments have not accounted for the impact of syndepositional deformation. The second approach is the classic tectonic modelling (sand-box experiments) is aimed essentially at understanding deformation, for example the deformation of a sediment wedge deposited onto a mobile salt layer. However, with this approach, the sediment transport processes are crudely modelled by adding each sediment layer uniformly, regardless of the potential influence of the sea-floor bathymetry on the depositional pattern. We designed a new tectono-stratigraphic modelling tank, which combines modelling of the turbiditic transport and deposition, and salt-related deformation driven by sediment loading. The set-up comprises a channel connected to a main water tank. A deformation box is placed at the mouth of the channel, on the base of the tank. The base of the box can be filled with various kinds of substrates either rigid (sand) or viscous (silicone polymer, simulating mobile salt layer having varying length and thickness). A mixture of fine-grained powder and water is maintained in suspension in a container, and then released and channelled toward the basin, generating an analogue of basin-floor fans or lobes. We investigated the effect of depositing several consecutive turbiditic lobes on the deformation of the salt body and its overburden. The dynamics of experimental turbidity currents lead to deposits whose thickness varied gradually laterally: the lobe is thick in the proximal region and thins progressively distally, thus creating a very gentle regional surface slope. As the fan grows by episodic deposition of successive turbiditic lobes, the model

Burial and exhumation of the Eisenhower Range, Transantarctic Mountains, based on thermochronological, sedimentary rock maturity and petrographic constraints

NASA Astrophysics Data System (ADS)

Prenzel, J.; Lisker, F.; Elsner, M.; Schöner, R.; Balestrieri, M. L.; Läufer, A. L.; Berner, U.; Spiegel, C.

2014-09-01

The Eisenhower Range is a N-S trending mountain range in the Transantarctic Mountains (TAM) adjacent to the NW Ross Sea Embayment. New AFT and apatite (U-Th-Sm)/He (AHe) data from vertical basement profiles supplemented by paleotemperature and pressure estimates derived from Beacon sandstones provide new quantitative results on regional burial evolution and first regional constraints on basin inversion and exhumation processes. AFT ages between 32 ± 2 and 259 ± 18 Ma and AHe ages of 37 ± 3-173 ± 16 Ma correlate positively with sample elevations. Thermal history modeling of these data and complementary thermal indications detect heating of the paleosurface on the Eisenhower Range to temperatures ≥ 80 °C subsequent to Ferrar magmatism, and constrain Late Eocene rapid cooling. Regression of modeled paleotemperatures against sample elevations refers to a high Jurassic (~ 45 °C/km) and a moderate Cretaceous-Eocene (28 ± 8 °C/km) geothermal gradient. The texture of Beacon sandstones supports strong mechanical compaction that requires a higher overburden than preserved in the stratigraphic record. Modeled paleotemperatures and pressures suggest basement burial that increases from Late Jurassic (0.7-1.1 km) to Eocene (1.8-2.1 km). The overburden comprises 0.7-1.1 km cumulative Beacon/Ferrar rocks and 0.7-1.4 km of post-Ferrar sediments. Rapid cooling of the whole sample suite between ~ 35 and 30 Ma implies fast erosion of the post-Ferrar sediments and (re-) exposure of underlying magmatic rocks. Subsequent differential sample cooling to present-day surface temperature infers ongoing exhumation by glacial incision enhanced by isostatic response to basin inversion. Decreasing amounts of exhumation from the coast (> 3 km) toward the interior (1.5-2.2 km) point to backstepping incision along the fault controlled Priestley Glacier. Substantial exhumation of the Eisenhower Range since the Late Eocene is hence triggered by both tectonic and climatic factors

Induced seismicity in a salt mine environment evaluated by a coupled continuum-discrete modelling.

NASA Astrophysics Data System (ADS)

Mercerat, E.; Souley, M.; Driad, L.; Bernard, P.

2005-12-01

Within the framework of a research project launched to assess the feasibility of seismic monitoring of underground growing cavities, this specific work focus on two main complementary axis: the validation of seismic monitoring techniques in salt mine environments, and the numerical modelling of deformation and failure mechanisms with their associated acoustic emissions, the induced microseismicity. The underground cavity under monitoring is located at Cerville (Lorraine, France) within a salt layer 180 m deep and it presents a rather regular cylindrical shape of 100 m diameter. Typically, the overburden is characterized by the presence of two competent layers with elasto-brittle behaviour and located 50 m above the salt layer. When the salt exploitation restarts, the cavity will progressively grow causing irreversible damage of the upper layers until its final collapse at a time scale of the order of one year. Numerical modelling of such a complex process requires a large scale model which takes into account both the growing cavity within the salt layer and the mechanical behaviour of the overburden where high deformation and fracturing is expected. To keep the elasto-brittle behaviour of the competent layers where most seismic damage is expected, we use the PFC code (Itasca Cons). To approach the other layers (mainly composed of marls and salt) which present more ductile and/or viscoplastic behaviour, a continuum approach based on the FLAC code (Itasca Cons) is employed. Numerous calibration process were needed to estimate the microproperties used in PFC to reproduce the macroscopic behaviour from laboratory tests performed on samples extracted from the competent layers. As long as the size of the PFC inclusion representing the brittle material is much higher than the core sample sizes, the scale effect of microproperties is examined. The next stage is to perform calculations on the basis of previous macroscopic and microproperties calibration results, and compare

Morphogenesis of the SW Balearic continental slope and adjacent abyssal plain, Western Mediterranean Sea

NASA Astrophysics Data System (ADS)

Camerlenghi, Angelo; Accettella, Daniela; Costa, Sergio; Lastras, Galderic; Acosta, Juan; Canals, Miquel; Wardell, Nigel

2009-06-01

We present the seafloor morphology and shallow seismic structure of the continental slope south-east of the Balearic promontory and of the adjacent Algero-Balearic abyssal plain from multibeam and chirp sonar data. The main purpose of this research was to identify the sediment pathways from the Balearic promontory to the Algero-Balearic deep basin from the Early Pliocene to the Present. The morphology of the southern Balearic margin is controlled by a SW-NE structural trend, whose main expressions are the Emile Baudot Escarpment transform fault, and a newly discovered WSW-ENE trend that affects the SW end of the escarpment and the abyssal plain. We relate the two structural trends to right-lateral simple shear as a consequence of the Miocene westward migration of the Gibraltar Arc. Newly discovered steep and narrow volcanic ridges were probably enabled to grow by local transtension along the transform margin. Abyssal plain knolls and seahills relate to the subsurface deformation of early stage halokinetic structures such as salt rollers, salt anticlines, and salt pillows. The limited thickness of the overburden and the limited amount of deformation in the deep basin prevent the formation of more mature halokinetic structures such as diapirs, salt walls, bulbs, and salt extrusions. The uppermost sediment cover is affected by a dense pattern of sub-vertical small throw normal faults resulting from extensional stress induced in the overburden by subsurface salt deformation structures. Shallow gas seismic character and the possible presence of an active polygonal fault system suggest upward fluid migration and fluid and sediment expulsion at the seafloor through a probable mud volcano and other piercement structures. One large debris flow deposit, named Formentera Debris Flow, has been identified on the lower slope and rise of the south Formentera margin. Based on current observations, we hypothesize that the landslide originating the Formentera Debris Flow occurred in

Forming artificial soils from waste materials for mine site rehabilitation

NASA Astrophysics Data System (ADS)

Yellishetty, Mohan; Wong, Vanessa; Taylor, Michael; Li, Johnson

2014-05-01

Surface mining activities often produce large volumes of solid wastes which invariably requires the removal of significant quantities of waste rock (overburden). As mines expand, larger volumes of waste rock need to be moved which also require extensive areas for their safe disposal and containment. The erosion of these dumps may result in landform instability, which in turn may result in exposure of contaminants such as trace metals, elevated sediment delivery in adjacent waterways, and the subsequent degradation of downstream water quality. The management of solid waste materials from industrial operations is also a key component for a sustainable economy. For example, in addition to overburden, coal mines produce large amounts of waste in the form of fly ash while sewage treatment plants require disposal of large amounts of compost. Similarly, paper mills produce large volumes of alkaline rejected wood chip waste which is usually disposed of in landfill. These materials, therefore, presents a challenge in their use, and re-use in the rehabilitation of mine sites and provides a number of opportunities for innovative waste disposal. The combination of solid wastes sourced from mines, which are frequently nutrient poor and acidic, with nutrient-rich composted material produced from sewage treatment and alkaline wood chip waste has the potential to lead to a soil suitable for mine rehabilitation and successful seed germination and plant growth. This paper presents findings from two pilot projects which investigated the potential of artificial soils to support plant growth for mine site rehabilitation. We found that pH increased in all the artificial soil mixtures and were able to support plant establishment. Plant growth was greatest in those soils with the greatest proportion of compost due to the higher nutrient content. These pot trials suggest that the use of different waste streams to form an artificial soil can potentially be used in mine site rehabilitation

Analogue of Caldera Dynamics: the Controlled Salt Cavern Collapse

NASA Astrophysics Data System (ADS)

Jousset, P. G.; Rohmer, J.

2012-12-01

Caldera collapse (or pit-crater) dynamics are inferred from geological observations and laboratory experiments. Here, we present an analogue of caldera collapse at field scale and possible analogy with large scale caldera dynamics. Through an original exploitation technique in sedimentary environment, a salt layer is emptied, leaving a brine-filled cavern, which eventually collapses after overburden falls into the cavern. Such a collapse was monitored in East France by many instruments (including GPS, extensometers, geophones, broadband seismological sensors, tiltmeter, gravity meter, … ), which allowed us to describe mechanisms of the collapse. Micro-seismicity is a good indicator of spatio-temporal evolution of physical properties of rocks prior to catastrophic events like volcanic eruptions or landslides and may be triggered by a number of causes including dynamic characteristics of processes in play or/and external forces. We show evidence of triggered micro-seismicity observed in the vicinity of this underground salt cavern prone to collapse by a remote M~7.2 earthquake, which occurred ~12000 kilometres away. High-dynamic broadband records reveal the strong time-correlation between a dramatic change in the rate of local high-frequency micro-seismicity and the passage of low-frequency seismic waves, including body, Love and Rayleigh surface waves. Pressure was lowered in the cavern by pumping operations of brine out of the cavern. We demonstrate the near critical state of the cavern before the collapse by means of 2D axisymmetric elastic finite-element simulations. Stress oscillations due to the seismic waves may have exceeded the strength required for the rupture of the complex media made of brine and rock triggering micro-earthquakes and leading to damage of the overburden and eventually collapse of the salt cavern. The increment of stress necessary for the failure of a Dolomite layer is of the same order or magnitude as the maximum dynamic stress magnitude

Bayesian resolution of TEM, CSEM and MT soundings: a comparative study

NASA Astrophysics Data System (ADS)

Blatter, D. B.; Ray, A.; Key, K.

2017-12-01

We examine the resolution of three electromagnetic exploration methods commonly used to map the electrical conductivity of the shallow crust - the magnetotelluric (MT) method, the controlled-source electromagnetic (CSEM) method and the transient electromagnetic (TEM) method. TEM and CSEM utilize an artificial source of EM energy, while MT makes use of natural variations in the Earth's electromagnetic field. For a given geological setting and acquisition parameters, each of these methods will have a different resolution due to differences in the source field polarization and the frequency range of the measurements. For example, the MT and TEM methods primarily rely on induced horizontal currents and are most sensitive to conductive layers while the CSEM method generates vertical loops of current and is more sensitive to resistive features. Our study seeks to provide a robust resolution comparison that can help inform exploration geophysicists about which technique is best suited for a particular target. While it is possible to understand and describe a difference in resolution qualitatively, it remains challenging to fully describe it quantitatively using optimization based approaches. Part of the difficulty here stems from the standard electromagnetic inversion toolkit, which makes heavy use of regularization (often in the form of smoothing) to constrain the non-uniqueness inherent in the inverse problem. This regularization makes it difficult to accurately estimate the uncertainty in estimated model parameters - and therefore obscures their true resolution. To overcome this difficulty, we compare the resolution of CSEM, airborne TEM, and MT data quantitatively using a Bayesian trans-dimensional Markov chain Monte Carlo (McMC) inversion scheme. Noisy synthetic data for this study are computed from various representative 1D test models: a conductive anomaly under a conductive/resistive overburden; and a resistive anomaly under a conductive/resistive overburden. In

Sill Emplacement and Forced Folding in the Canterbury Basin, offshore SE New Zealand

NASA Astrophysics Data System (ADS)

Reeves, Jennifer; Magee, Craig; Jackson, Christopher

2017-04-01

Sill-complexes are common in sedimentary basins worldwide. The geometry of sill-complexes and their associated deformation can be used to unravel tectono-magmatic events. For example, intruding magma may uplift the overburden and the free surface to produce forced folds that are typically either dome-shaped or flat-topped. These four-way dip closures can form suitable hydrocarbon traps and dating of onlapping of sedimentary strata allows the timing of emplacement, relative to hydrocarbon generation and migration to be assessed. Furthermore, these forced folds directly overlie the forcing intrusion and their volume is commonly assumed to equal that of the emplaced magma. This relationship between folds, which may be expressed that the Earth's surface, and magma volume is fundamental for volcano predication due to the use of ground deformation as a proxy for the location and magnitude of future eruptions. However, recent studies have demonstrated that fluidization of weak host rock can accommodate magma during non-brittle emplacement, producing little or no overburden deformation. Assessing the mechanics of intrusion-induced forced folding is therefore critical to a variety of Earth Science disciplines. Here, we use 3D seismic reflection data map four sills at a high-resolution within the underexplored Canterbury Basin, offshore SE New Zealand. We demonstrate that: (i) despite similar emplacement levels, forced folds are only developed above two of the sills, with no apparent uplift above the other two sills; (ii) onlap of sedimentary onto forced folds and associated hydrothermal vents indicates two episodes of sill emplacement in the Whaingaroan (34.6-31.8 Ma) and Opoitian (5.33-3.7 Ma); and (iii) intra-fold thickness is variable, with lower intervals within the folds displaying a flat-topped geometry overlain by sedimentary strata displaying dome-shaped folding. We discuss the formation of these forced folds as assess the role of non-brittle and inelastic

Perceived effects of attending physician workload in academic medical intensive care units: a national survey of training program directors.

PubMed

Ward, Nicholas S; Read, Richard; Afessa, Bekele; Kahn, Jeremy M

2012-02-01

Increases in the size and number of American intensive care units have not been accompanied by a comparable increase in the critical care physician workforce, raising concerns that intensivists are becoming overburdened by workload. This is especially concerning in academic intensive care units where attending physicians must couple teaching duties with patient care. We performed an in-person and electronic survey of the membership of the Association of Pulmonary and Critical Care Medicine Program Directors, soliciting information about patient workload, other hospital and medical education duties, and perceptions of the workplace and teaching environment of their intensive care units. Eighty-four out of a total 121 possible responses were received from program directors or their delegates, resulting in a response rate of 69%. The average daily (SD) census (as perceived by the respondents) was 18.8 ± 8.9 patients, and average (SD) maximum service size recalled was 24.1 ± 9.9 patients. Twenty-seven percent reported no policy setting an upper limit for the daily census. Twenty-eight percent of respondents felt the average census was "too many" and 71% felt the maximum size was "too many." The median (interquartile range) patient-to-attending physician ratio was 13 (10-16). When categorized according to this median, respondents from intensive care units with high patient/physician ratios (n = 31) perceived significantly more time constraints, more stress, and difficulties with teaching trainees than respondents with low patient/physician ratios (n = 40). The total number of non-nursing healthcare workers per patient was similar in both groups, suggesting that having more nonattending physician staff does not alleviate perceptions of overwork and stress in the attending physician. Academic intensive care unit physicians that direct fellowship programs frequently perceived being overburdened in the intensive care unit. Understaffing intensive care units with attending

Biofilm-induced calcium carbonate precipitation: application in the subsurface

NASA Astrophysics Data System (ADS)

Phillips, A. J.; Eldring, J.; Lauchnor, E.; Hiebert, R.; Gerlach, R.; Mitchell, A. C.; Esposito, R.; Cunningham, A. B.; Spangler, L.

2012-12-01

We have investigated mitigation strategies for sealing high permeability regions, like fractures, in the subsurface. This technology has the potential to, for example, improve the long-term security of geologically-stored carbon dioxide (CO2) by sealing fractures in cap rocks or to mitigate leakage pathways to prevent contamination of overlying aquifers from hydraulic fracturing fluids. Sealing technologies using low-viscosity fluids are advantageous since they potentially reduce the necessary injection pressures and increase the radius of influence around injection wells. In this technology, aqueous solutions and suspensions are used to promote microbially-induced mineral precipitation which can be applied in subsurface environments. To this end, a strategy was developed to twice seal a hydraulically fractured, 74 cm (2.4') diameter Boyles Sandstone core, collected in North-Central Alabama, with biofilm-induced calcium carbonate (CaCO3) precipitates under ambient pressures. Sporosarcina pasteurii biofilms were established and calcium and urea containing reagents were injected to promote saturation conditions favorable for CaCO3 precipitation followed by growth reagents to resuscitate the biofilm's ureolytic activity. Then, in order to evaluate this process at relevant deep subsurface pressures, a novel high pressure test vessel was developed to house the 74 cm diameter core under pressures as high as 96 bar (1,400 psi). After determining that no impact to the fracture permeability occurred due to increasing overburden pressure, the fractured core was sealed under subsurface relevant pressures relating to 457 meters (1,500 feet) below ground surface (44 bar (650 psi) overburden pressure). After fracture sealing under both ambient and subsurface relevant pressure conditions, the sandstone core withstood three times higher well bore pressure than during the initial fracturing event, which occurred prior to biofilm-induced CaCO3 mineralization. These studies suggest

Geologic controls on the formation of lakes in north-central Florida

USGS Publications Warehouse

Kindinger, Jack G.; Davis, Jeffrey B.; Flocks, James G.; Pitman, Janet K.; Carroll, Alan R.

1998-01-01

Fluid exchange between surficial waters and groundwater, as well as the processes that control this exchange, are of critical concern to water management districts and planners. Digital high-resolution seismic systems were used to collect geophysical data from 30 lakes of north-central Florida. Although using seismic profile data in the past has been less than successful, the use of digital technology has increased the potential for success. Seismic profiles collected from the lakes of north-central Florida have shown the potential application of these techniques in understanding the formation of individual lakes. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: 1) karstification or dissolution of the underlying limestone, and 2) me collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Lake size and shape are a factor of the thickness of overburden and size of the collapse or subsidence and/or clustering of depressions allowing for lake development. Lake development is through progressive sequence stages to maturity that can be delineated into geomorphic types. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phases: (1) active subsidence or collapse phase (young) - the open to partially filled collapse structures typically associated with sink holes; (2) transitional phase (middle age) - the sinkhole is plugged as the voids within the collapse are filled with sediment, periodic reactivation may occur; (3) baselevel phase (mature) - active sinkholes are progressively plugged by the continual erosion of material into the basin, and eventually sediment fills the basins; and (4) polje (drowned prairie) - broad flat-bottom basins located within the epiphreatic zone that are inundated at high

Hydrology and water-quality at the Weldon Spring radioactive waste-disposal sites, St Charles County, Missouri

USGS Publications Warehouse

Kleeschulte, M.J.; Emmett, L.F.

1987-01-01

Water samples from five monitoring wells adjacent to raffinate pits storing low-level radioactive waste contained concentrations of nitrate as nitrogen ranging from 53 to 990 milligrams per liter. Most samples also had maximum concentrations of calcium (900 milligrams per liter), sodium (340 milligrams per liter), sulfate (320 milligrams per liter), lithium (1,700 micrograms), strontium (1,900 micrograms per liter), and uranium (86 micrograms per liter). The raffinate pits also had large concentrations of these constituents. A water balance made on the raffinate pits indicated a 0.04 to 0.08 inch per day decrease in the water level that cannot be attributed to meterological conditions. These data and seismically-detected areas of saturated overburden beneath one raffinate pit and possibly adjacent to three other pits indicate leakage from the pits. (USGS)

Development of a Bulk-Format System to Harvest, Handle, Store, and Deliver High-Tonnage Low-Moisture Switchgrass Feedstock

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

Womac, Alvin; Groothuis, Mitch; Westover, Tyler

2013-09-24

This project evaluates and compares comprehensive feedstock logistics systems (FLS), where a FLS is defined to comprehensively span from biomass material standing in a field to conveyance of a uniform, industrial-milled product into the throat of a biomass conversion facility (BCF). Elements of the bulk-format FLS evaluated in this project include: field-standing switchgrass dry chopped into bulk format on the farm, hauled (either loose or bulk compacted) to storage, stored with confining overburden in a protective facility, reclaimed and conveyed to bulk-format discharge, bulk compacted into an ejector trailer, and conveyed as bulk flow into the BCF. In this FLSmore » evaluation, bulk storage bins served as a controlled and sensored proxy for large commercial stacks protected from moisture with a membrane cover.« less

[Clinical drug trials in Germany--an assessment of current status from the viewpoint of industry].

PubMed

Baumbauer, E

1996-01-01

Drug development today is a highly professional and costly affair, whereby quality and speed are decisive competitive factors in a global setting. Germany is in the process of losing its attractiveness for clinical drug research as evidenced by a significant decrease in funding of clinical drug research which at the moment amounts to about 1.5 billion DM/year. This decrease is due to an adverse environment created by a certain anxiety in public opinion regarding technological advances, an overburden of regulations, lack of an infrastructure in hospitals to work according to GCP and a regulatory agency which has to compete with momentarily more effective agencies in Europe (UK, France). A joint effort between industry and the medical profession is called for to change this situation for the better.

Biological intrusion of low-level-waste trench covers

NASA Astrophysics Data System (ADS)

Hakonson, T. E.; Gladney, E. S.

The long-term integrity of low-level waste shallow land burialsites is dependent on the interaction of physical, chemical, and biological factors that modify the waste containment system. The need to consider biological processes as being potentially important in reducing the integrity of waste burial site cover treatment is demonstrated. One approach to limiting biological intrusion through the waste cover is to apply a barrier within the profile to limit root and animal penetration with depth. Experiments in the Los Alamos Experimental Engineered Test Facility were initiated to develop and evaluate biological barriers that are effective in minimizing intrusion into waste trenches. The experiments that are described employ four different candidate barrier materials of geologic origin. Experimental variables that will be evaluated, in addition to barrier type, are barrier depth and sil overburden depth.

Underground coal operators install several new longwall mining systems

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

Fiscor, S.

2008-02-15

Several new names appear in the annual US Longwall Census, but the population remains the same: 52 although the number of longwall mines dropped from 40 to 47. CONSOL Energy remains the leader with 12 faces. Robert E. Murray owns 8 longwall mines followed by Arch Coal with 5 and Foundation Coal with 3. West Virginia has 13 longwalls followed by 9 in Pennsylvania, 7 in Utah and 6 in Alabama. The article describes CONSOL Energy's operations. A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries,more » depth of cut, model of equipment used (shearer, haulage system, roof support, face conveyor, stage loader, crusher, electrical controls and voltage to face). 2 tabs.« less

[Efficiency of Brazilian States and the Federal District in the public kidney transplant system based on DEA (Data Envelopment Analysis) and the Malmquist index].

PubMed

Costa, Cassia Kely Favoretto; Balbinotto Neto, Giácomo; Sampaio, Luciano Menezes Bezerra

2014-08-01

The objective of this study was to evaluate the efficiency of Brazilian States and the Federal District in the public kidney transplant system and their productivity trends from 2006 to 2011. The authors used Data Envelopment Analysis (DEA) with slack and the Malmquist index with slack. Inputs included spending on hospital services and health professionals in the system. The output was the number of kidney transplants performed in each State. The data showed a significant discrepancy between States in the number of kidney transplants. The transplant system's inefficiency may result from inadequate management, failure to comply with national guidelines, inactive hospital transplant committees, and overburdened hospital staff. Institutional changes promoted by the Brazilian Ministry of Health (procedures improvement and standardization) failed to increase productivity in most States during this period.

Coupled Finite Element ? Potts Model Simulations of Grain Growth in Copper Interconnects

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

Radhakrishnan, Balasubramaniam; Gorti, Sarma B

The paper addresses grain growth in copper interconnects in the presence of thermal expansion mismatch stresses. The evolution of grain structure and texture in copper in the simultaneous presence of two driving forces, curvature and elastic stored energy difference, is modeled by using a hybrid Potts model simulation approach. The elastic stored energy is calculated by using the commercial finite element code ABAQUS, where the effect of elastic anisotropy on the thermal mismatch stress and strain distribution within a polycrystalline grain structure is modeled through a user material (UMAT) interface. Parametric studies on the effect of trench width and themore » height of the overburden were carried out. The results show that the grain structure and texture evolution are significantly altered by the presence of elastic strain energy.« less

Analysis of photopole data reduction models

NASA Technical Reports Server (NTRS)

Cheek, James B.

1987-01-01

An analysis of the total impulse obtained from a buried explosive charge can be calculated from displacement versus time points taken from successive film frames of high speed motion pictures of the explosive event. The indicator of that motion is a pole and baseplate (photopole), which is placed on or within the soil overburden. Here, researchers are concerned with the precision of the impulse calculation and ways to improve that precision. Also examined here is the effect of each initial condition on the curve fitting process. It is shown that the zero initial velocity criteria should not be applied due to the linear acceleration versus time character of the cubic power series. The applicability of the new method to photopole data records whose early time motions are obscured is illustrated.

Status and Recent Results from the Cream Experiment

NASA Astrophysics Data System (ADS)

Seo, E. S.; Ahn, H. S.; Bhoyar, P.; Eaton, J.; Ganel, O.; Han, J. H.; Haque, A.; Kim, K. C.; Kim, M. H.; Lee, M. H.; Lee, S. E.; Lutz, L.; Malinin, A.; Ofoha, O.; Ryu, S. S.; Smith, B. P.; Vartanyan, A.; Walpole, P.; Wu, J.; Yoo, J. H.; Yoon, Y. S.; Anderson, T.; Conklin, N. B.; Coutu, S.; Geske, M.; Mognet, S. I.; Barbier, L.; Link, J. T.; Mitchell, J. W.; Barrau, A.; Buénerd, M.; Coste, B.; Derome, L.; Mangin-Brinet, M.; Putze, A.; Sallaz-Damaz, Y.; Bazer-Bachi, R.; Beatty, J. J.; Brandt, T. J.; Bigongiari, G.; Maestro, P.; Zei, R.; Jeon, J. A.; Na, G.; Nam, J.; Nam, S.; Park, I. H.; Park, N. H.; Yang, J.; Menchaca-Rocha, A.; Nutter, S.

2011-06-01

The Cosmic Ray Energetics And Mass (CREAM) balloon-borne experiment has accumulated ~156 days of exposure during five successful flights over Antarctica. Energy measurements are made with a transition radiation detector and an ionization calorimeter. Charge measurements are made with timing scintillators, pixelated Si, and Cherenkov detectors to minimize the effect of backscattered particles. High energy cosmic-ray data were collected over a wide energy range from ~ 1010 to ~ 1015 eV at an average altitude of ~38.5 km, with ~3.9 g/cm2 atmospheric overburden. All cosmic-ray elements from protons (Z = 1) to iron nuclei (Z = 26) are separated with excellent charge resolution. The instrument performance, results from the ongoing data analysis, and their implications on cosmic-ray origin, acceleration and propagation are discussed.

From orientation to magnitudes in paleostress determinations using fault slip data

NASA Astrophysics Data System (ADS)

Angelier, Jacques

Determinations of reduced stress tensors using fault slip data yield the orientation of principal stress axes and the ratio Φ of the differences between principal stress magnitudes. The use of rupture and friction laws allows determination of the two remaining unknowns, that is, the reconstruction of the complete stress tensor. Taking into account the depth of overburden brings an additional constraint. The method is applied and discussed in the case of the Hoover Dam site (western U.S.A.), where large data sets and rock mechanics information are available. Differences between intact sample and rock mass properties account for apparent disagreements between paleostress levels determined in similar tectonic environments. Pore pressure plays an important role; where information about pore pressure is absent, zero and hydrostatic pore pressure cases should be considered as limits.

Cavity detection and delineation research. Report 5: Electromagnetic (Radar) techniques applied to cavity detection

NASA Astrophysics Data System (ADS)

Ballard, R. F., Jr.

1983-07-01

This study evaluated four different radar systems to determine their effectiveness in locating subterranean cavities. Tests were conducted at three well-documented sites: Vicksburg, Miss.; Medford Cave, Fla. (near Ocala); and Manatee Springs, Fla. (near Chiefland). None of the radar systems was effective at the Vicksburg, Miss., site because of extremely high conductivities encountered in the overburden materials which were comprised primarily of silts (loess) and clays. The following radar systems were used in this study: (a) A pulsed system fabricated and operated by personnel from Texas A/M University; (b) A pulsed system commercially manufactured by GSSI operated by the owners, Technos, Inc.; (c) A pulsed system developed, fabricated, and operated by personnel from SwRI; and (d) A continuous wave system development, fabricated and operated by personnel from LLNL.

Survey of nine surface mines in North America. [Nine different mines in USA and Canada

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

Hayes, L.G.; Brackett, R.D.; Floyd, F.D.

This report presents the information gathered by three mining engineers in a 1980 survey of nine surface mines in the United States and Canada. The mines visited included seven coal mines, one copper mine, and one tar sands mine selected as representative of present state of the art in open pit, strip, and terrace pit mining. The purpose of the survey was to investigate mining methods, equipment requirements, operating costs, reclamation procedures and costs, and other aspects of current surface mining practices in order to acquire basic data for a study comparing conventional and terrace pit mining methods, particularly inmore » deeper overburdens. The survey was conducted as part of a project under DOE Contract No. DE-AC01-79ET10023 titled The Development of Optimal Terrace Pit Coal Mining Systems.« less

Cosmic ray topography

NASA Astrophysics Data System (ADS)

Bressler, Matthew; Goodwin, Lydia; Kryemadhi, Abaz

2017-11-01

Cosmic ray muons are produced when high energy particles interact with nuclei in Earth's atmosphere. Muons make up the majority of charged particles that reach sea level and are the only particles (apart from neutrinos) that can penetrate to significant depths underground. The muon flux underground decreases approximately exponentially as a function of depth. We use a cosmic ray detector developed by the QuarkNet Program at Fermi National Laboratory to map the topography of the mountain above an abandoned Pennsylvania Turnpike tunnel by analyzing muon flux at different rock overburdens. Cosmic ray muons have been used in this capacity before to search for hidden chambers in pyramids and for mapping volcanoes. This study provides a unique field experience to learn about particle physics and particle detectors, which could be of interest to students and teachers in physics.

PROSPECT - A precision oscillation and spectrum experiment

NASA Astrophysics Data System (ADS)

Langford, T. J.; PROSPECT Collaboration

2015-08-01

Segmented antineutrino detectors placed near a compact research reactor provide an excellent opportunity to probe short-baseline neutrino oscillations and precisely measure the reactor antineutrino spectrum. Close proximity to a reactor combined with minimal overburden yield a high background environment that must be managed through shielding and detector technology. PROSPECT is a new experimental effort to detect reactor antineutrinos from the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory, managed by UT Battelle for the U.S. Department of Energy. The detector will use novel lithium-loaded liquid scintillator capable of neutron/gamma pulse shape discrimination and neutron capture tagging. These enhancements improve the ability to identify neutrino inverse-beta decays (IBD) and reject background events in analysis. Results from these efforts will be covered along with their implications for an oscillation search and a precision spectrum measurement.

New maps of Federal coal ( USA).

USGS Publications Warehouse

Wayland, R.G.

1981-01-01

Compilation and analysis of publicly available data on Federal coal are resulting in voluminous map sets showing coal isopachs, structure contours, and overburden isopachs on each known minable coal bed. As of spring 1981, there are available from the US Geological Survey Open-File Services Section in Denver map sets at 1:24 000 scale or microfiche sets covering approximately 470 of the ultimately 1400 quadrangles in the program. A typical map set has a short text and about 20 plates, including a data sheet; a Federal mineral ownership map; and correlation charts. For each coal bed, there are isopachs, structure contours, stripping limits, and mining ratios extending as far as the data will permit, regardless of coal ownership. Reserve base tonnages and relative development potentials are calculated, but only for unleased Federal coal areas. -from Author

Research and design progress of the Jinping Neutrino Experiment

NASA Astrophysics Data System (ADS)

Wang, Zhe

2018-01-01

Thanks to the 2400 m overburden and the long distance to commercial reactors, the China Jinping Underground Laboratory (CJPL) is an ideal site for low background neutrino experiments. The Jinping Neutrino Experiment will perform an in-depth research on solar neutrinos, geo-neutrinos and supernova relic neutrinos. Many efforts were devoted to the R&D of the experimental proposal. A new type of liquid scintillator, with high light-yield and Cherenkov and scintillation separation capability, is being developed. The assay and selection of low radioactive stainless-steel (SST) was carried out. A wide field-of-view of 90 degree and high-geometry-efficiency of 98% light concentrator is developed. At the same time, a 1-ton prototype is constructed and placed underground at Jinping laboratory. The simulation and analysis software, electromagnetic calorimeter function, rock damage zone simulation will also be introduced briefly.

Geology and energy resources of the Sand Butte Rim NW Quadrangle, Sweetwater County, Wyoming

USGS Publications Warehouse

Roehler, Henry W.

1979-01-01

The Sand Butte Rim NW 71-minute quadrangle occupies 56 square miles of an arid, windy, sparsely vegetated area of ridges and valleys on the east flank of the Rock Springs uplift in southwest Wyoming. The area is underlain by a succession of sedimentary rocks, about 20,000 feet thick, that includes 28 formations ranging in age from Cambrian to Tertiary. Upper Cretaceous and lower Tertiary formations crop out and dip 3?-6? southeast. They are unfaulted and generally homoclinal, but a minor anticlinal nose is present. Older rocks in the subsurface are faulted and folded. Coal resources are estimated to be nearly I billion short tons of subbituminous coal, in beds more than 2.5 feet thick, under less than 3,000 feet of overburden, in the Fort Union Formation of Paleocene age and the Lance and Almond Formations of Cretaceous age.

Two-dimensional model studies of the effect of supersonic aircraft operations on the stratospheric ozone content

NASA Technical Reports Server (NTRS)

Whitten, R. C.; Borucki, W. J.; Poppoff, I. G.; Latt, L.; Widhopf, G. F.; Capone, L. A.; Reigel, C. A.

1981-01-01

For a fleet of 250 aircraft, the change in the ozone column is predicted to be very close to zero; in fact, the ozone overburden may actually increase as a result of show that above 25 to 30 km the ozone abundance decreases via catalytic destruction, but at lower heights it increases, mainly as a result of coupling with odd hydrogen species. Water vapor released in the engine exhaust is predicted to cause ozone decreases; for the hypothetical engines used in the study, the total column ozone changes due to water vapor emission largely offset the predicted ozone increases due to NOx emission. The actual effect of water vapor may be less than calculated because present models do not include thermal feedback. Feedback refers to the cooling effect of additional water vapor that would tend to slow the NOx reactions which destroy ozone.

Conflict of technologies for water and sanitation in developing countries.

PubMed

Bannerman, R R

2000-01-01

Borehole water supplies, in basement rock aquifers in the West Africa Sub-region, face potential pollution hazards as a result of their close location within the same geological environments as indiscriminately sited latrines, rubbish dumps, farms and animal watering points in the communities. The heterogeneous nature of the overburden and fractures in the bedrock constitute relatively fast flow paths for surface water contaminated mainly by bacteria and nitrates which enhance the pollution of the groundwater and boreholes. To improve the drinking water quality, some measures have been taken to minimize the hazards. Further studies are required to understand better the nature and scale of the problem and to avoid the apparent conflict of technologies. It is necessary to incorporate improvements in sanitation into rural water supply projects, if the otherwise good drinking water source should not be lost to society's wastes.

Study of multi-muon bundles in cosmic ray showers detected with the DELPHI detector at LEP

NASA Astrophysics Data System (ADS)

Delphi Collaboration; Abreu, P.; Adam, W.; Adzic, P.; Albrecht, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P. P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.-D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G. J.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.-H.; Begalli, M.; Behrmann, A.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P. S. L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T. J. V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J. M.; Buschbeck, B.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, N.; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S. U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M. J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; da Silva, T.; da Silva, W.; Della Ricca, G.; de Angelis, A.; de Boer, W.; de Clercq, C.; de Lotto, B.; de Maria, N.; de Min, A.; de Paula, L.; di Ciaccio, L.; di Simone, A.; Doroba, K.; Drees, J.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M. C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, E.; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Goncalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Herr, H.; Hoffman, J.; Holmgren, S.-O.; Holt, P. J.; Houlden, M. A.; Jackson, J. N.; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, E. K.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, F.; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B. P.; Kerzel, U.; King, B. T.; Kjaer, N. J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, F.; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J. H.; Lopez, J. M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.-C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; McNulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Moenig, K.; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J. P.; Palka, H.; Papadopoulou, Th. D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M. E.; Polok, G.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Rames, J.; Read, A.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Sander, C.; Savoy-Navarro, A.; Schwickerath, U.; Sekulin, R.; Shellard, R. C.; Siebel, M.; Sisakian, A.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Tabarelli, T.; Taffard, A. C.; Tegenfeldt, F.; Timmermans, J.; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tome, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.-L.; Tyapkin, I. A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; van Dam, P.; van Eldik, J.; van Remortel, N.; van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A. J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimin, N. I.; Zintchenko, A.; Zupan, M.

2007-11-01

The DELPHI detector at LEP has been used to measure multi-muon bundles originating from cosmic ray interactions with air. The cosmic events were recorded in “parasitic mode” between individual e+e- interactions and the total live time of this data taking is equivalent to 1.6 × 106 s. The DELPHI apparatus is located about 100 m underground and the 84 metres rock overburden imposes a cutoff of about 52 GeV/c on muon momenta. The data from the large volume Hadron Calorimeter allowed the muon multiplicity of 54,201 events to be reconstructed. The resulting muon multiplicity distribution is compared with the prediction of the Monte Carlo simulation based on CORSIKA/QGSJET01. The model fails to describe the abundance of high multiplicity events. The impact of QGSJET internal parameters on the results is also studied.

Geologic Map of Upper Cretaceous and Tertiary Strata and Coal Stratigraphy of the Paleocene Fort Union Formation, Rawlins-Little Snake River Area, South-Central Wyoming

USGS Publications Warehouse

Hettinger, R.D.; Honey, J.G.; Ellis, M.S.; Barclay, C.S.V.; East, J.A.

2008-01-01

This report provides a map and detailed descriptions of geologic formations for a 1,250 square mile region in the Rawlins-Little Snake River coal field in the eastern part of the Washakie and Great Divide Basins of south-central Wyoming. Mapping of geologic formations and coal beds was conducted at a scale of 1:24,000 and compiled at a scale of 1:100,000. Emphasis was placed on coal-bearing strata of the China Butte and Overland Members of the Paleocene Fort Union Formation. Surface stratigraphic sections were measured and described and well logs were examined to determine the lateral continuity of individual coal beds; the coal-bed stratigraphy is shown on correlation diagrams. A structure contour and overburden map constructed on the uppermost coal bed in the China Butte Member is also provided.

Beyond the obvious limits of ore deposits: The use of mineralogical, geochemical, and biological features for the remote detection of mineralization

USGS Publications Warehouse

Kelley, D.L.; Kelley, K.D.; Coker, W.B.; Caughlin, B.; Doherty, M.E.

2006-01-01

deposits with a low-temperature thermal history. A number of newly investigated secondary far field features include the development of reduced columns by electrochemical processes in transported overburden, geochemical dispersion related to the expulsion of groundwater from tectonic and seismic compression, dispersion of vapor above ore deposits, and geochemical dispersion related to biological processes. Redox gradients have been found between underlying reduced and overlying oxidized environments associated with sulfide bodies, which result in mass transfer through electro-chemical dispersion. Recent studies have characterized the pH, oxidation-reduction potential (ORP), and self potential (SP) in overburden overlying sulfide-hosted gold and VMS deposits. Lateral migration of metals in groundwater is well understood from normal groundwater flow, but the processes responsible for vertical mass transfer of groundwater and its dissolved components have been recognized only recently. One process, termed cyclical dilatancy pumping, expels groundwater during and after earthquake events, which can cause the redistribution of metals around deposits in some environments. Soil gases are of interest owing to their high degree of mobility through the vadose zone in transported overburden. Numerous soil gas species (CO2, O2, Hg, Rn, He, sulfur compounds, and light hydrocarbons) have been measured and interpreted as diagnostic of some buried mineral deposits, and some evidence suggests a possible link between vapor dispersion and metal enrichment in soil. Geochemical enrichment in plant material and soils through successive growth-death cycles is well established, but the important role of microorganisms is now increasingly evident. Microorganisms significantly enhance the kinetics of sulfide oxidation and influence the distribution of metals around ore deposits. The presence of metal-resistant bacteria and enhanced concentrations of sulfate-reducing bacteria in exotic overburd

Soil and Vegetation Project. A Detailed Study of Five Overburden Cores and Six Disposal Areas Along the Divide Section Tennessee-Tombigbee Waterway.

DTIC Science & Technology

1983-06-17

a c . 9.. a. 0 GIOV 0’ 0" u4 1% 1’ 0 𔃺 01 0% 01 0" -A < a) 0 C6 CN 0 t 0 -4 C, 1 ol El4 c4- 0 (n 1 0 en 01 (14 0 Q *- ou x --- -14 La.) C)X V) z...clearly related to the initial concentration of viable cells in the inoculant. Determinations of the ability of viable Rhizobia to infect and nodulate...temperatures after 28 days storage have been planted. The extent of nodule formation will be determined. 354 ._ _ ~ Figuire 1. Viable Rhizobia cells

Subsurface Structure of the Bushveld Igneous Complex, South Africa: An Application of Geophysics

NASA Astrophysics Data System (ADS)

Vallejo, G.; Galindo, B. L.; Carranza, V.; Gomez, C. D.; Ortiz, K.; Castro, J. G.; Falzone, C.; Guandique, J.; Emry, E.; Webb, S. J.; Nyblade, A.

2014-12-01

South Africa is host to the largest single known platinum group metal supply in the world. The Bushveld Igneous Complex, spanning 300x400 kilometers, hosts hundreds of years' worth of platinum, chromite, vanadium, and other ore. Its wealth of these metals is tied directly to the large layered igneous intrusion that formed roughly 2061 million years ago. The extraction of platinum is vital to the industrial world - as these metals are widely used in the automotive industry, dental restorations, computer technology, in addition to many other applications. In collaboration with the Africa Array geophysics field school and the Penn State Summer Research Opportunities Program (SROP), we surveyed the Modikwa mine located along the border of the provinces of Mpumalanga and Limpopo in South Africa. The following techniques were applied to survey the area of interest: seismic refraction and reflection, gravity, magnetics, electrical resistivity, and electromagnetics. The data collected were used to determine the depth to bedrock and to identify potential mining hazards from dykes and faults in the bedrock. Several areas were studied and with the combination of the above-mentioned methods several possible hazards were identified. One broad, major dyke that was located in a prior aeromagnetic survey and several previously undetected, parallel, minor dykes were identified in the region. The overburden thickness was determined to be ̴4-5 meters in some regions, and as thin as several centimeters in others. This section of rock and soil lies above an area where platinum will likely be mined in the future. The removal of overburden can be accomplished by using power shovels or scrapers; while remaining material can be contained with the use of galvanized steel culverts. Additionally, a number of joints were located that may have allowed water to accumulate underground. The models created from the data permit us to estimate which hazards could be present in different parts of the

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining

PubMed Central

Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of “cantilever beam and elastic foundation beam” was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the

Vadose zone processes delay groundwater nitrate reduction response to BMP implementation as observed in paired cultivated vs. uncultivated potato rotation fields

NASA Astrophysics Data System (ADS)

Jiang, Y.; Nyiraneza, J.; Murray, B. J.; Chapman, S.; Malenica, A.; Parker, B.

2017-12-01

Nitrate leaching from crop production contributes to groundwater contamination and subsequent eutrophication of the receiving surface water. A study was conducted in a 7-ha potato-grain-forages rotation field in Prince Edward Island (PEI), Canada during 2011-2016 to link potato rotation practices and groundwater quality. The field consists of fine sandy loam soil and is underlain by 7-9 m of glacial till, which overlies the regional fractured ;red-bed; sandstone aquifer. The water table is generally located in overburden close to the bedrock interface. Field treatments included one field zone taken out of production in 2011 with the remaining zones kept under a conventional potato rotation. Agronomy data including crop tissue, soil, and tile-drain water quality were collected. Hydrogeology data including multilevel monitoring of groundwater nitrate and hydraulic head and data from rock coring for nitrate distribution in overburden and bedrock matrix were also collected. A significant amount of nitrate leached below the soil profile after potato plant kill (referred to as topkill) in 2011, most of it from fertilizer N. A high level of nitrate was also detected in the till vadose zone through coring in December 2012 and through multilevel groundwater sampling from January to May 2014 in both cultivated and uncultivated field zones. Groundwater nitrate concentrations increased for about 2.5 years after the overlying potato field was removed from production. Pressure-driven uniform flow processes dominate water and nitrate transport in the vadose zone, producing an apparently instant water table response but a delayed groundwater quality response to nitrate leaching events. These data suggest that the uniform flow dominated vadose zone in agricultural landscapes can cause the accumulation of a significant amount of nitrate originated from previous farming activities, and the long travel time of this legacy nitrate in the vadose zone can result in substantially delayed

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining.

PubMed

Yang, Jing-Hu; Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of "cantilever beam and elastic foundation beam" was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the propagation

Numerical simulations of depressurization-induced gas production from gas hydrate reservoirs at the Walker Ridge 312 site, northern Gulf of Mexico

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

Myshakin, Evgeniy M.; Gaddipati, Manohar; Rose, Kelly

2012-06-01

In 2009, the Gulf of Mexico (GOM) Gas Hydrates Joint-Industry-Project (JIP) Leg II drilling program confirmed that gas hydrate occurs at high saturations within reservoir-quality sands in the GOM. A comprehensive logging-while-drilling dataset was collected from seven wells at three sites, including two wells at the Walker Ridge 313 site. By constraining the saturations and thicknesses of hydrate-bearing sands using logging-while-drilling data, two-dimensional (2D), cylindrical, r-z and three-dimensional (3D) reservoir models were simulated. The gas hydrate occurrences inferred from seismic analysis are used to delineate the areal extent of the 3D reservoir models. Numerical simulations of gas production from themore » Walker Ridge reservoirs were conducted using the depressurization method at a constant bottomhole pressure. Results of these simulations indicate that these hydrate deposits are readily produced, owing to high intrinsic reservoir-quality and their proximity to the base of hydrate stability. The elevated in situ reservoir temperatures contribute to high (5–40 MMscf/day) predicted production rates. The production rates obtained from the 2D and 3D models are in close agreement. To evaluate the effect of spatial dimensions, the 2D reservoir domains were simulated at two outer radii. The results showed increased potential for formation of secondary hydrate and appearance of lag time for production rates as reservoir size increases. Similar phenomena were observed in the 3D reservoir models. The results also suggest that interbedded gas hydrate accumulations might be preferable targets for gas production in comparison with massive deposits. Hydrate in such accumulations can be readily dissociated due to heat supply from surrounding hydrate-free zones. Special cases were considered to evaluate the effect of overburden and underburden permeability on production. The obtained data show that production can be significantly degraded in comparison with a

The Dresden Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics - Status and first physics program

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

Ilgner, Ch.

Favored by the low background in underground laboratories, low-background accelerator-based experiments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, protected from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and carbon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, inmore » the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise using the same High-Purity Ge detector at several sites has shown that, with a combination of 45 m rock overburden, as can be found in the Felsenkeller underground site in Dresden, and an active veto against the remaining muon flux, in a typical nuclear astrophysics setup a background level can be achieved that is similar to the deep underground scenario as in the Gran- Sasso underground laboratory, for instance. Recently, a muon background study and geodetic measurements were carried out by the REGARD group. It was estimated that the rock overburden at the place of the future ion accelerator is equivalent to 130 m of water. The maximum muon flux measured was 2.5 m{sup -2} sr{sup -1} s{sup -1}, in the direction of the tunnel entrance. Based on this finding, a used 5 MV pelletron tandem accelerator with 250 μA up-charge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is in progress and far advanced. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and

Selected translations of the Russian literature on the electrogeochemical sampling technique called CHIM (chastichnoe izvlechennye metallov)

USGS Publications Warehouse

Bloomstein, Edward I.; Bloomstein, Eleana; Hoover, D.B.; Smith, D.B.

1990-01-01

As part of our research into new methods for the assessment of mineral deposits, the U.S. Geological Survey has recently begun investigation of the CHIM method. As part of our studies, translation of a Russian manual on the CHIM methodology and eight articles from the Russian literature were transit ted to provide background for our own research. The translations were done by Earth Science Translation Services of Albuquerque, New Mexico, and are presented as received, without editing on our part. Below is a bibliography of the translated articles.For approximately the past 20 years Russian geoscientists have been applying an electrogeochemical sampling technique given the Russian acronym CHIM, derived from Chastichnoe Izvlechennye Metallov which translates as "partial extraction of metals". In this technique a direct current is introduced into the earth through collector electrodes similar to "porous pots" used in electrical geophysical applications. The solution in the cathode is dilute nitric acid, and current is passed through the cathode for times ranging from 6 hours to 48 hours or more. Electrical connections to the nitric acid are made through an inner conductor that is typically spectroscopically pure graphite. At the cathode, mobile cations collect on the graphite or in the nitric acid solution, both of which serve as the geochemical sampling media. These media are then analyzed by appropriate methods for the ions of interest. In most applications of the CHIM method only mobile cations are sampled, although Russian literature does refer to collection of anions as well. More recently the CHIM method has been applied by the Peoples Republic of China and the Indian Geological Survey.The literature indicates that the method has advantages over other geochemical sampling techniques by providing increased sensitivity to the metals being searched for, especially where deposits are covered by substantial overburden. In some cases success has been claimed with

Carbonate clumped-isotope constraints on the burial and exhumation history of the Colorado Plateau

NASA Astrophysics Data System (ADS)

Ryb, U.; Lloyd, M. K.; Eiler, J. M.

2016-12-01

Reconstruction of the thermal history of rocks is key to study the geodynamic evolution of sedimentary basins. Carbonate clumped-isotope measurements of minerals formed or re-equilibrated at elevated temperatures can constrain thermal histories of rocks. Experimental constraints on solid state isotopic reordering in carbonates let us translate clumped-isotope measurements into quantitative statements about the thermal history, and thus burial and exhumation. We use this approach to constrain peak burial temperatures of Paleozoic rocks across the Colorado Plateau, sampled carbonate rocks from the southwestern Plateau margin and from borehole cores in the Plateau interior. We sub-sampled specific fabrics (fossils, cements, etc.), determined their calcite and dolomite proportions using XRD, and analyzed clumped-isotope compositions (reported as apparent temperatures using Stolper and Eiler's (2015) calibration) for pure calcite or dolomite samples (>97 wt.%). At the Plateau margin, calcite and dolomite apparent temperatures are 49-79°C and 67-97°C, respectively. The maximum apparent temperature constrains the minimum peak burial temperature. The distribution of calcite apparent temperatures independently constrains the maximum burial temperature as follows: If the "coldest" sample had an initial apparent temperature of 20°C, then its observed value can be explained by isotopic reordering to a peak temperature of 105-120°C. We therefore hypothesize peak temperature at the base of the Paleozoic was 97-120°C. At the Plateau interior, apparent temperatures of Mississippian calcite samples are depth-dependent: Samples cored from <2km depth have apparent temperatures of 54-68°C; similar samples from 3km depth have apparent temperatures of 105-165°C and a smaller variability between sub-samples, interpreted to result from isotopic reordering at >150°C. Assuming a surface temperature of 20°C and a thermal gradient of 25°C km-1, we calculate total overburden (above

A study of the United States coal resources

NASA Technical Reports Server (NTRS)

Ferm, J. C.; Muthig, P. J.

1982-01-01

Geologically significant coal resources were identified. Statistically controlled tonnage estimates for each resource type were prepared. Particular emphasis was placed on the identification and description of coals in terms of seam thickness, inclination, depth of cover, discontinuities caused by faulting and igneous intrusion, and occurrence as isolated or multiseam deposits. The national resource was organized into six major coal provinces: the Appalachian Plateau, the Interior Basins, the Gulf Coastal Plain, the Rocky Mountain Basins, the High Plains, and North Alaska. Each basin within a province was blocked into subareas of homogeneous coal thickness. Total coal tonnage for a subarea was estimated from an analysis of the cumulative coal thickness derived from borehole or surface section records and subsequently categorized in terms of seam thickness, dip, overburden, multiseam proportions, coal quality, and tonnage impacted by severe faulting and igneous intrusions. Confidence intervals were calculated for both subarea and basin tonnage estimates.

Geophysical exploration in vicinity of the Unicorn Cave, South Harz Mountains, Germany

NASA Astrophysics Data System (ADS)

Kaufmann, Georg; Romanov, Douchko; Nielbock, Ralf

2010-05-01

The Unicorn Cave in the southern Harz Mountains in Germany is located in an outcrop of dolomite from the Zechstein formation, which is underlain by Grauwacke rocks. The cave, about 600 meters long, consists of several large chambers, which are connected by a gallery following the main fault alignments in E/W, NE/SW, and NW/SE direction. The overburden of the cave is shallow, between 10 and 30 m. We have used this cave site to perform a sensitivity test for both gravimetric and geoelectic methods above the cave. Additionally, geoelectic mapping has been used to assess the thickness of the cave sediments in one of the chambers. Our results show a clear signal in the Bouguer anomaly, which can only be explained by a combined model of the void space and the sediment filling. Geoelectric results are less clear, but support the gravimetry.

Dobson spectrophotometer ozone measurements during international ozone rocketsonde intercomparison

NASA Technical Reports Server (NTRS)

Parsons, C. L.

1980-01-01

Measurements of the total ozone content of the atmosphere, made with seven ground based instruments at a site near Wallops Island, Virginia, are discussed in terms for serving as control values with which the rocketborne sensor data products can be compared. These products are profiles of O3 concentration with altitude. By integrating over the range of altitudes from the surface to the rocket apogee and by appropriately estimating the residual ozone amount from apogee to the top of the atmosphere, a total ozone amount can be computed from the profiles that can be directly compared with the ground based instrumentation results. Dobson spectrophotometers were used for two of the ground-based instruments. Preliminary data collected during the IORI from Dobson spectrophotometers 72 and 38 are presented. The agreement between the two and the variability of total ozone overburden through the experiment period are discussed.

Secondary migration and leakage of methane from a major tight-gas system

NASA Astrophysics Data System (ADS)

Wood, James M.; Sanei, Hamed

2016-11-01

Tight-gas and shale-gas systems can undergo significant depressurization during basin uplift and erosion of overburden due primarily to the natural leakage of hydrocarbon fluids. To date, geologic factors governing hydrocarbon leakage from such systems are poorly documented and understood. Here we show, in a study of produced natural gas from 1,907 petroleum wells drilled into a Triassic tight-gas system in western Canada, that hydrocarbon fluid loss is focused along distinct curvilinear pathways controlled by stratigraphic trends with superior matrix permeability and likely also structural trends with enhanced fracture permeability. Natural gas along these pathways is preferentially enriched in methane because of selective secondary migration and phase separation processes. The leakage and secondary migration of thermogenic methane to surficial strata is part of an ongoing carbon cycle in which organic carbon in the deep sedimentary basin transforms into methane, and ultimately reaches the near-surface groundwater and atmosphere.

Rationale for an HIV / AIDS prevention and mitigation strategy for Africa: combatting the multisectoral impact of the epidemic.

PubMed

Lyerly, W H

1996-01-01

Unlike most infectious diseases in Africa, HIV/AIDS affects the urban elite as well as the rural poor, and generally during their most economically productive years. An increase in deaths among young adults of the magnitude predicted is likely to have substantial adverse effects on economic, political, and military/security stability throughout Africa. AIDS is causing increased stress on fragile African economic infrastructures as labor productivity declines, particularly in agricultural, labor-dependent economies. AIDS is causing obstacles to trade, foreign investment and tourism. Health systems and social coping mechanisms already are overburdened. High rates of HIV infection among police and military personnel threaten internal security. Furthermore, the demobilization of military forces in Africa may exacerbate the epidemic when HIV-infected soldiers return home and spread the virus. This presentation will illustrate why African AIDS Programs must be expanded to mitigate the multisectoral impact of the epidemic while preserving its spread.

A search for cosmogenic production of β-neutron emitting radionuclides in water

NASA Astrophysics Data System (ADS)

Dazeley, S.; Askins, M.; Bergevin, M.; Bernstein, A.; Bowden, N. S.; Shokair, T. M.; Jaffke, P.; Rountree, S. D.; Sweany, M.

2016-06-01

Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of β-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the β-neutron measurement, we also provide a first look at isolating single-β producing radionuclides following muon-induced hadronic showers as a check of the detection capabilities of WATCHBOY. The data taken over 207 live days indicates a 9Li production yield upper limit of 1.9 ×10-7μ-1g-1cm2 at ~400 m water equivalent (m.w.e.) overburden at the 90% confidence level. In this work the 9Li signal in WATCHBOY was used as a proxy for the combined search for 9Li and 8He production. This result will provide a constraint on estimates of antineutrino-like backgrounds in future water-based antineutrino detectors.

3D Cosmic Ray Muon Tomography from an Underground Tunnel

DOE PAGES

Guardincerri, Elena; Rowe, Charlotte Anne; Schultz-Fellenz, Emily S.; ...

2017-03-31

Here, we present an underground cosmic ray muon tomographic experiment imaging 3D density of overburden, part of a joint study with differential gravity. Muon data were acquired at four locations within a tunnel beneath Los Alamos, New Mexico, and used in a 3D tomographic inversion to recover the spatial variation in the overlying rock–air interface, and compared with a priori knowledge of the topography. Densities obtained exhibit good agreement with preliminary results of the gravity modeling, which will be presented elsewhere, and are compatible with values reported in the literature. The modeled rock–air interface matches that obtained from LIDAR withinmore » 4 m, our resolution, over much of the model volume. This experiment demonstrates the power of cosmic ray muons to image shallow geological targets using underground detectors, whose development as borehole devices will be an important new direction of passive geophysical imaging.« less

3D Cosmic Ray Muon Tomography from an Underground Tunnel

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

Guardincerri, Elena; Rowe, Charlotte Anne; Schultz-Fellenz, Emily S.

Here, we present an underground cosmic ray muon tomographic experiment imaging 3D density of overburden, part of a joint study with differential gravity. Muon data were acquired at four locations within a tunnel beneath Los Alamos, New Mexico, and used in a 3D tomographic inversion to recover the spatial variation in the overlying rock–air interface, and compared with a priori knowledge of the topography. Densities obtained exhibit good agreement with preliminary results of the gravity modeling, which will be presented elsewhere, and are compatible with values reported in the literature. The modeled rock–air interface matches that obtained from LIDAR withinmore » 4 m, our resolution, over much of the model volume. This experiment demonstrates the power of cosmic ray muons to image shallow geological targets using underground detectors, whose development as borehole devices will be an important new direction of passive geophysical imaging.« less

"The Adopted Children of ART": expert clients and role tensions in ART provision in Uganda.

PubMed

Kyakuwa, Margaret; Hardon, Anita; Goldstein, Zoe

2012-01-01

The implementation of the greater involvement of people living with HIV (GIPA) principle in Ugandan AIDS care is described by focusing on the engagement of expert clients in two rural health centers during a time of antiretroviral therapy (ART) scale-up. We contrast how the expert clients help overburdened nurses to manage the well-attended ART programs in the public and in the nongovernmental organization clinic. They are unpaid, but acquire preferential status in the ART program because of their knowledge of AIDS medicines (and its adverse effects) and because of the compassionate care that they provide. Despite the assistance provided, nurses in the public facility felt threatened in their professional status by these expert clients, who were seen to overstep the boundaries of their role. We pay particular attention to the double burden for HIV-positive nurses, who fear stigma, and (unlike the expert patients) keep their HIV status secret.

Clay deposits of the Tierra Colorado district, southern Orange County, California

USGS Publications Warehouse

Daviess, Steven Norman; Bramlette, M.N.

1953-01-01

The clay of this district is being mined for fire brick by the Vitrofrax Corporation. Much of the clay contains 35 percent or more of alumina and between 1 and 2 percent of iron oxide. Production is largely from an underground mine as the best clay deposit known in the district occurs on the side of a steep hill with more than 100 feet of sandstone overlying most of it. The good clay deposits occur at the base of an Eocene sandstone formation, and overlie mottled clays with a high iron content that are residual deposits formed on an old weathered surface. Mapping indicates that the clay deposits are very lenticular, though all occur at the same stratigraphic position, and they grade laterally into sandy clay and quartz sand. Topographic relief and the dip of the strata preclude finding large areas where the clay strata have relatively little overburden.

"My House Is the Hospital": Housing and Health and Wellbeing among Persons Living with HIV/AIDS in Northern Malawi.

PubMed

Mkandawire, Paul; Arku, Godwin; Atari, Odwa; Madut, Kon; Luginaah, Isaac; Dixon, Jenna

2015-11-01

This paper reports findings of a qualitative study and draws on the political ecology of health framework to examine the links between housing and health among people living with HIV/AIDS (PLWAs) in Northern Malawi in a wider context in which the epidemic has overburdened the country's hospitals, thereby transferring the responsibility for care from government to families. The findings suggest that poor housing conditions, rooted in colonial and postcolonial policy failure, may undermine the amount, as well as the quality, of palliative care available to PLWAs. It was also found that the high cost of renting, discrimination, and poor landlord-tenant relationships imposed significant financial and emotional burden on PLWAs, thereby undermining their ability to meet dietary needs, stay healthy, and adhere to treatment. Furthermore, customary norms around property inheritance hampered women's housing security and their ability to cope with the disease. The paper concludes by making relevant policy recommendations.

Probing Sub-GeV Mass Strongly Interacting Dark Matter with a Low-Threshold Surface Experiment.

PubMed

Davis, Jonathan H

2017-11-24

Using data from the ν-cleus detector, based on the surface of Earth, we place constraints on dark matter in the form of strongly interacting massive particles (SIMPs) which interact with nucleons via nuclear-scale cross sections. For large SIMP-nucleon cross sections, the sensitivity of traditional direct dark matter searches using underground experiments is limited by the energy loss experienced by SIMPs, due to scattering with the rock overburden and experimental shielding on their way to the detector apparatus. Hence, a surface-based experiment is ideal for a SIMP search, despite the much larger background resulting from the lack of shielding. We show using data from a recent surface run of a low-threshold cryogenic detector that values of the SIMP-nucleon cross section up to approximately 10^{-27}  cm^{2} can be excluded for SIMPs with masses above 100 MeV.

First search for a dark matter annual modulation signal with NaI(Tl) in the Southern Hemisphere by DM-Ice17

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

Barbosa de Souza, E.; Cherwinka, J.; Cole, A.

The first search for a dark matter annual modulation signal with NaI(Tl) target material in the Southern Hemisphere conducted with the DM-Ice17 experiment is presented. DM-Ice17 consists of 17 kg of NaI(Tl) scintillating crystal under 2200 m.w.e. overburden of Antarctic glacial ice. The analysis presented here utilizes a 60.8 kg yr exposure. While unable to exclude the signal reported by DAMA/LIBRA, the DM-Ice17 data are consistent with no modulation in the energy range of 4-20 keV, providing the strongest limits on WIMP candidates from a direct detection experiment located in the Southern Hemisphere. Additionally, the successful deployment and stable operationmore » of 17 kg of NaI(Tl) crystal over 3.5 years establishes the South Pole ice as a viable location for future underground, low-background experiments.« less

The business of medicine: how to overcome financial obstacles and secure financing for your private practice and ancillary services business.

PubMed

Nayor, David

2012-01-01

Doctors across the country who operate private medical practices are facing increasing financial obstacles, namely shrinking income as a result of rising costs and lower reimbursements. In addition, as hospitals have become overburdened many physicians have opened up private surgical centers; magnetic resonance imaging and computed tomography and positron emission tomography scanning facilities; pathology labs; colonoscopy/endoscopy suites; lithotripsy centers; and other medical businesses typically performed within the hospital. Moreover, many doctors seek loans to purchase existing practices or for their capital contribution in medical partnerships. The past decade has thus seen a significant increase in the number of doctors taking out small business loans. Indeed, banks view the healthcare industry as a large growth market. This article includes practical information, advice, and resources to help doctors to secure bank financing for their practices, ancillary services business, real estate, and equipment on the best possible market terms.

Implications of ground-deformation measurements across earth fissures in subsidence areas in the southwestern USA

USGS Publications Warehouse

Holzer, Thomas L.

2010-01-01

Ground deformation was monitored at earth fissures in areas of land subsidence induced by groundwater extraction in the southwestern United States. The ground deformation is consistent with the mechanism that fissures are caused by horizontal strains generated by bending of overburden in response to localized differential compaction. Subsidence profiles indicated that localized differential subsidence occurred across the fissures and that maximum convex-upward curvature was at the fissure. The overall shape of the profile stayed similar with time, and maximum curvature remained stationary at the fissure. Horizontal displacements were largest near the fissure, and generally were small to negligible away from the fissure. Maximum tensile horizontal strains were at the fissure and coincided with maximum curvature in the subsidence profiles. Horizontal tensile strain continued to accumulate at fissures after they formed with rates of opening ranging from 30 to 120 microstrain/year at fissures in Arizona.

3D Cosmic Ray Muon Tomography from an Underground Tunnel

NASA Astrophysics Data System (ADS)

Guardincerri, Elena; Rowe, Charlotte; Schultz-Fellenz, Emily; Roy, Mousumi; George, Nicolas; Morris, Christopher; Bacon, Jeffrey; Durham, Matthew; Morley, Deborah; Plaud-Ramos, Kenie; Poulson, Daniel; Baker, Diane; Bonneville, Alain; Kouzes, Richard

2017-05-01

We present an underground cosmic ray muon tomographic experiment imaging 3D density of overburden, part of a joint study with differential gravity. Muon data were acquired at four locations within a tunnel beneath Los Alamos, New Mexico, and used in a 3D tomographic inversion to recover the spatial variation in the overlying rock-air interface, and compared with a priori knowledge of the topography. Densities obtained exhibit good agreement with preliminary results of the gravity modeling, which will be presented elsewhere, and are compatible with values reported in the literature. The modeled rock-air interface matches that obtained from LIDAR within 4 m, our resolution, over much of the model volume. This experiment demonstrates the power of cosmic ray muons to image shallow geological targets using underground detectors, whose development as borehole devices will be an important new direction of passive geophysical imaging.

Potential of groundwater contamination by polybrominated diphenyl ethers (PBDEs) in a sensitive bedrock aquifer (Canada)

NASA Astrophysics Data System (ADS)

Levison, Jana; Novakowski, Kent; Reiner, Eric J.; Kolic, Terry

2012-03-01

It is necessary to understand the presence, movement, and persistence of contaminants in aquifers to develop adequate groundwater protection plans. Fractured bedrock aquifers with thin overburden cover are very sensitive to contamination, and little is known about transport processes from the ground surface to depth in this setting. This study was undertaken to investigate the potential of groundwater contamination by polybrominated diphenyl ethers (PBDEs), which are flame retardants, in a natural fractured bedrock aquifer in Canada proven to be sensitive to contamination. PBDEs, which had not been previously measured in groundwater in detail, were detected in the study aquifer at concentrations greater than those observed in surface-water bodies. Potential sources include manure, septic tanks, and the atmosphere. From this scoping study, it is evident that additional surveys of PBDE concentrations in groundwater are warranted, especially in settings with high potential source concentrations coupled with sensitive aquifers.

Stakeholder Meeting: Integrated Knowledge Translation Approach to Address the Caregiver Support Gap.

PubMed

Holroyd-Leduc, Jayna M; McMillan, Jacqueline; Jette, Nathalie; Brémault-Phillips, Suzette C; Duggleby, Wendy; Hanson, Heather M; Parmar, Jasneet

2017-03-01

Family caregivers are an integral and increasingly overburdened part of the health care system. There is a gap between what research evidence shows is beneficial to caregivers and what is actually provided. Using an integrated knowledge translation approach, a stakeholder meeting was held among researchers, family caregivers, caregiver associations, clinicians, health care administrators, and policy makers. The objectives of the meeting were to review current research evidence and conduct multi-stakeholder dialogue on the potential gaps, facilitators, and barriers to the provision of caregiver supports. A two-day meeting was attended by 123 individuals. Three target populations of family caregivers were identified for discussion: caregivers of seniors with dementia, caregivers in end-of-life care, and caregivers of frail seniors with complex health needs. The results of this meeting can and are being used to inform the development of implementation research endeavours and policies targeted at providing evidence-informed caregiver supports.

An evaluation of in situ ozone sensor performance during a cold frontal passage

NASA Technical Reports Server (NTRS)

Parsons, C. L.

1978-01-01

The capabilities of the electrochemical concentration cell ozonesonde for measuring the vertical profile of atmospheric ozone were studied during a three day experiment at Wallops Island, Virginia, and Norfolk, Virginia. Using ancillary measurements at the surface and the spectrophotometer, it was concluded that the ozonesonde measures the total ozone overburden to within 10% of the real value. By releasing the balloon-borne instruments at a rate of four per day at each of the two sites, an indication was obtained of the temporal and spatial scales of atmospheric ozone variability. No significant effects of a weak cold front passage or of the loss of insolation at night were seen. An isolated incident of anomalously high ozone concentration at the peak of the profile was attributed to sporadic instrument performance effects. The data base currently available is not adequate for determining an exact cause of the anomaly.

Audiomagnetotelluric data to characterize the Revett-type copper-silver deposits at Rock Creek in the Cabinet Mountains Wilderness, Montana

USGS Publications Warehouse

Sampson, Jay A.; Rodriguez, Brian D.

2011-01-01

The Revett-type deposits at Rock Creek are part of the concealed stratabound copper-silver deposits located in the Cabinet Mountains Wilderness of Montana. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. Geologic, geochemical, geophysical, and mineral resources data are being evaluated with existing and new mineral deposit models to predict the possibility and probability of undiscovered deposits in covered terranes. To help characterize the size, resistivity, and depth of the mineral deposit concealed beneath thick overburden, a regional southwest-northeast audiomagnetotelluric sounding profile was acquired. Further studies will attempt to determine if induced polarization parameters can be extracted from the magnetotelluric data to determine the size of the mineralized area. The purpose of this report is to release the audiomagnetotelluric sounding data collected along that southwest-northeast profile. No interpretation of the data is included.

Culturally adapting a physical activity intervention for Somali women: the need for theory and innovation to promote equity.

PubMed

Murray, Kate E; Ermias, Azieb; Lung, Amber; Mohamed, Amina Sheik; Ellis, B Heidi; Linke, Sarah; Kerr, Jacqueline; Bowen, Deborah J; Marcus, Bess H

2017-03-01

There is pressing need for innovation in clinical research to more effectively recruit, engage, retain, and promote health among diverse populations overburdened by health disparities. The purpose of this study is to provide a detailed illustration of the cultural adaptation of an evidence-based intervention to bolster translational research with currently underserved communities. The cultural adaptation heuristic framework described by Barrera and colleagues is applied to the adaptation of a physical activity evidence-based intervention with adult Somali women. Widespread changes were required to ensure program feasibility and acceptability, including the reduction of assessment protocols and changes discordant with current trends in physical activity research. The cultural adaptation of evidence-based interventions offers an important mechanism for reducing health disparities. Improved reporting standards, assessment of features relevant to underserved communities, and greater funding requirements to ensure better representation are needed to promote more widespread access for all people.

Summary of events and geotechnical factors leading to decommissioning of the Strategic Petroleum Reserve (SPR) facility at Weeks Island, Louisiana

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

Neal, J.T.; Bauer, S.J.; Ehgartner, B.L.

1996-10-01

A sinkhole discovered over the edge of the Strategic Petroleum Reserve storage facility at Weeks Island salt dome, Louisiana, led to decommissioning the site during 1995--1998, following extensive diagnostics in 1994. The sinkhole resulted from mine-induced fractures in the salt which took may years to develop, eventually causing fresh water to leak into the storage chamber and dissolve the overlying salt, thus causing overburden collapse into the void. Prior to initiating the oil removal, a freeze wall was constructed at depth around the sinkhole in 1995 to prevent water inflow; a freeze plug will remain in place until the minemore » is backfilled with brine in 1997--8, and stability is reached. Residual oil will be removed; environmental monitoring has been initiated and will continue until the facility is completely plugged and abandoned, and environmental surety is achieved.« less

[The Psychotherapeutic Evening Clinic: Concept and First Results].

PubMed

Dinger, Ulrike; Komo-Lang, Miriam; Schauenburg, Henning; Herzog, Wolfgang; Nikendei, Christoph

2018-05-30

This article reports about a new treatment setting, the Psychotherapeutic Evening Clinic at the University Hospital Heidelberg. The treatment intensity is ranked between intensive, full-day inpatient and day-clinic programs in hospitals and less frequent outpatient psychotherapy according to the Germany Psychotherapy Guideline. Patients attend the Evening Clinic on 3 evenings per week for 3 hours each. During this time, they receive group therapy, individual therapy, mindfulness exercises and psychotherapeutic ward rounds. The first experiences with the new setting are positive, a specific advantage is the possibility to include daily hassles and everyday stressors as well as patients' strengths and resources into the treatment. Therapeutic challenges are the potential of overburdening patients with an already high impairment. On the structural and political level it will be important to ensure funding for the new treatment setting. © Georg Thieme Verlag KG Stuttgart · New York.

Dewatering of the Jenkins open pit uranium mine

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

Straskraba, V.; Kissinger, L.E.

Mining of low grade uranium sandstones in the Jenkins open pit mine in the Shirley Basin, Wyoming was troubled by slope failures and wet conditions in the pit. Since the mine was expanding toward a river, the possibility of drainage from this river into the mine raised serious concern during the mine planning. A baseline hydrogeologic study was performed and dewatering measures were designed with the help of a numerical mathematical model. A combination of dewatering wells installed from the surface around the perimeter of the pit and horizontal drains in areas of high slope failure potential substantially improved themore » mining conditions and slope stability. This procedure consequently led to the successful ore recovery from the highly saturated sandstone strata. The development of drawdown during the dewatering of two separated aquifers in the overburden was close to that predicted by the model.« less

An antemortem guide for the assessment of stranded Australian sea snakes (Hydrophiinae).

PubMed

Gillett, Amber K; Flint, Mark; Mills, Paul C

2014-12-01

Marine snakes of the subfamily Hydrophiinae are obligate ocean dwellers, unlike their amphibious counterparts, the sea kraits (Laticaudinae), and as such they are often referred to as 'true' sea snakes. This specialization means that the presence of a true sea snake on a beach is atypical and likely indicates disease or injury. Traumatic injuries such as eye, jaw, and spinal lesions have been observed in stranded sea snakes and may present as acute injury or progress to chronic debilitation. Diseases, such as neoplasia, leukemia, and parasite overburden, have also been seen in wild sea snakes, and these animals may present similarly. Sick, moribund, or deceased sea snakes are intermittently found washed ashore along Australian beaches, and these specimens may prove valuable as bioindicators of marine health. This review is intended as a guide to the diagnostic investigation of sick or injured sea snakes by suitably qualified people.

Teleretinal screening for diabetic retinopathy in six Los Angeles urban safety-net clinics: initial findings.

PubMed

Ogunyemi, Omolola; Terrien, Elizabeth; Eccles, Alicia; Patty, Lauren; George, Sheba; Fish, Allison; Teklehaimanot, Senait; Ilapakurthi, Ramarao; Aimiuwu, Otaren; Baker, Richard

2011-01-01

Diabetic retinopathy is a leading cause of blindness in US adults. This paper presents initial results of a teleretinal screening project for diabetic retinopathy involving six Los Angeles safety net clinics. A total of 1,943 patients have been screened for diabetic retinopathy by three ophthalmologist readers, with 416 receiving a recommendation for referral to specialty care. Of the cases recommended for referral, 24 had proliferative diabetic retinopathy, 62 had severe non-proliferative diabetic retinopathy (NPDR), 60 had moderate NPDR, 19 had mild NPDR, 138 had a non-diabetic condition, such as glaucoma, 63 had clinically significant macular edema without retinopathy and 50 had non-gradable images. Between 3% and 12.2% of retinal images taken at the clinics were assessed by readers as inadequate for any interpretation. The study shows the feasibility and challenges of teleretinal screening for diabetic retinopathy in urban areas facing specialist shortages and an overburdened, under-resourced safety net care-delivery system.

[Burnout: a useful diagnosis?].

PubMed

Thalhammer, Matthias; Paulitsch, Klaus

2014-01-01

In psychiatry, burnout is a relevant phenomenon. A large number of individuals is feeling overburdened at work. In contrast to mental disorders, the term 'burnout' is not perceived as stigmatizing, making it therefore easier for afflicted persons to seek help. The term 'burnout syndrome' was mentioned 1974 for the first time in scientific literature. Today, there is a range of partially contradictory definitions and explanations for burnout and the burnout syndrome, respectively. In most studies, burnout is assessed by the Maslach Burnout Inventory, which is neither useful for determining the degree of pathology nor for distinguishing burnout from mental disorders such as depression. It is expected that the burnout syndrome will not be used in modern diagnostic classification systems, because of its unclear definition and conceptual contradictions. On these grounds, it appears reasonable to define burnout as long-term professional overload and a noteworthy risk factor for physical diseases and mental disorders.

Ore Reserve Estimation of Saprolite Nickel Using Inverse Distance Method in PIT Block 3A Banggai Area Central Sulawesi

NASA Astrophysics Data System (ADS)

Khaidir Noor, Muhammad

2018-03-01

Reserve estimation is one of important work in evaluating a mining project. It is estimation of the quality and quantity of the presence of minerals have economic value. Reserve calculation method plays an important role in determining the efficiency in commercial exploration of a deposit. This study was intended to calculate ore reserves contained in the study area especially Pit Block 3A. Nickel ore reserve was estimated by using detailed exploration data, processing by using Surpac 6.2 by Inverse Distance Weight: Squared Power estimation method. Ore estimation result obtained from 30 drilling data was 76453.5 ton of Saprolite with density of 1.5 ton/m3 and COG (Cut Off Grade) Ni ≥ 1.6 %, while overburden data was 112,570.8 tons with waste rock density of 1.2 ton/m3 . Striping Ratio (SR) was 1.47 : 1 smaller than Stripping Ratio ( SR ) were set of 1.60 : 1.

Probabilistic liquefaction triggering based on the cone penetration test

USGS Publications Warehouse

Moss, R.E.S.; Seed, R.B.; Kayen, R.E.; Stewart, J.P.; Tokimatsu, K.

2005-01-01

Performance-based earthquake engineering requires a probabilistic treatment of potential failure modes in order to accurately quantify the overall stability of the system. This paper is a summary of the application portions of the probabilistic liquefaction triggering correlations proposed recently proposed by Moss and co-workers. To enable probabilistic treatment of liquefaction triggering, the variables comprising the seismic load and the liquefaction resistance were treated as inherently uncertain. Supporting data from an extensive Cone Penetration Test (CPT)-based liquefaction case history database were used to develop a probabilistic correlation. The methods used to measure the uncertainty of the load and resistance variables, how the interactions of these variables were treated using Bayesian updating, and how reliability analysis was applied to produce curves of equal probability of liquefaction are presented. The normalization for effective overburden stress, the magnitude correlated duration weighting factor, and the non-linear shear mass participation factor used are also discussed.

How the University of Texas system responded to the need for interim storage of low-level radioactive waste materials.

PubMed

Emery, Robert J

2012-11-01

Faced with the prospect of being unable to permanently dispose of low-level radioactive wastes (LLRW) generated from teaching, research, and patient care activities, component institutions of the University of Texas System worked collaboratively to create a dedicated interim storage facility to be used until a permanent disposal facility became available. Located in a remote section of West Texas, the University of Texas System Interim Storage Facility (UTSISF) was licensed and put into operation in 1993, and since then has provided safe and secure interim storage for up to 350 drums of dry solid LLRW at any given time. Interim storage capability provided needed relief to component institutions, whose on-site waste facilities could have possibly become overburdened. Experiences gained from the licensing and operation of the site are described, and as a new permanent LLRW disposal facility emerges in Texas, a potential new role for the storage facility as a surge capacity storage site in times of natural disasters and emergencies is also discussed.

Study on Reventment-Protected and Non-Bottom-Protected Plunge Pool of High Arch Dam

NASA Astrophysics Data System (ADS)

Yingkui, Wang; Quxiu, Cao; Fanhui, Kong

2018-05-01

Lots of high arch dam have the characteristics of “High head, Large discharge and Narrow river valley”, therefore, the security researches of energy dissipation were always the focus in these hydro-projects. Statistically, the trajectory type energy dissipation is the most widely used in the built high arch dams, and the water plunge poor were always set downstream the dam body. However, the widely used protected plunge poor need large investment with the disadvantage of complicated operation and maintenance. Along with the construction of concrete high arch dam in the Southwest China, the river overburden and water cushion were deep in dam site, which is becoming a new characteristic of these hydro-projects. Accordingly, the deep water cushion can be used for the energy dissipation design, such as the “Reventment-Protected and Non-Bottom-Protected Plunge Pool”, which has the advantage of more simplified project design and more economy investment.

Accelerating Thermokarst Transforms Ice-Cored Terrain Triggering a Downstream Cascade to the Ocean

NASA Astrophysics Data System (ADS)

Rudy, A. C. A.; Lamoureux, S. F.; Kokelj, S. V.; Smith, I. R.; England, J. H.

2017-11-01

Recent climate warming has activated the melt-out of relict massive ice in permafrost-preserved moraines throughout the western Canadian Arctic. This ice that has persisted since the last glaciation, buried beneath as little as 1 m of overburden, is now undergoing accelerated permafrost degradation and thermokarst. Here we document recent and intensifying thermokarst activity on eastern Banks Island that has increased the fluvial transport of sediments and solutes to the ocean. Isotopic evidence demonstrates that a major contribution to discharge is melt of relict ground ice, resulting in a significant hydrological input from thermokarst augmenting summer runoff. Accelerated thermokarst is transforming the landscape and the summer hydrological regime and altering the timing of terrestrial to marine and lacustrine transfers over significant areas of the western Canadian Arctic. The intensity of the landscape changes demonstrates that regions of cold, continuous permafrost are undergoing irreversible alteration, unprecedented since deglaciation ( 13 cal kyr B.P.).

Characterization of Vertical Ozonesonde Measurements in Equatorial Regions Utilizing the Cooperative Enterprise SHADOZ

NASA Technical Reports Server (NTRS)

Schmidlin, F. J.; Thompson, A. M.; Holdren, D. H.; Northam, E. T.; Witte, J. C.; Oltmans, S. J.; Hoegger, B.; Levrat, G. M.; Kirchhoff, V.

2000-01-01

Vertical ozone profiles between the Equator and 10 S latitude available from the Southern Hemisphere Additional Ozone (SHADOZ) program provide consistent data Ozone sets from up to 10 sounding locations. SHADOZ designed to provide independent ozone profiles in the tropics for evaluation of satellite ozone data and models has made available over 600 soundings over the period 1998-1999. These observations provide an ideal data base for the detailed description of ozone and afford differential comparison between sites. TOMS total ozone when compared with correlative integrated total ozone overburden from the sondes is found to be negatively biased when using the classical constant mixing ratio procedure to determine residual ozone. On the other hand, the climatological method proposed by McPeters and Labow appears to give consistent results but is positively biased. The longer then two years series of measurements also was subjected to harmonic analysis to examine data cycles. These will be discussed as well.

Spreading volcanoes

USGS Publications Warehouse

Borgia, A.; Delaney, P.T.; Denlinger, R.P.

2000-01-01

As volcanoes grow, they become ever heavier. Unlike mountains exhumed by erosion of rocks that generally were lithified at depth, volcanoes typically are built of poorly consolidated rocks that may be further weakened by hydrothermal alteration. The substrates upon which volcanoes rest, moreover, are often sediments lithified by no more than the weight of the volcanic overburden. It is not surprising, therefore, that volcanic deformation includes-and in the long term is often dominated by-spreading motions that translate subsidence near volcanic summits to outward horizontal displacements around the flanks and peripheries. We review examples of volcanic spreading and go on to derive approximate expressions for the time volcanoes require to deform by spreading on weak substrates. We also demonstrate that shear stresses that drive low-angle thrust faulting from beneath volcanic constructs have maxima at volcanic peripheries, just where such faults are seen to emerge. Finally, we establish a theoretical basis for experimentally derived scalings that delineate volcanoes that spread from those that do not.

Adoption of online health management tools among healthy older adults: An exploratory study.

PubMed

Zettel-Watson, Laura; Tsukerman, Dmitry

2016-06-01

As the population ages and chronic diseases abound, overburdened healthcare systems will increasingly require individuals to manage their own health. Online health management tools, quickly increasing in popularity, have the potential to diminish or even replace in-person contact with health professionals, but overall efficacy and usage trends are unknown. The current study explored perceptions and usage patterns among users of online health management tools, and identified barriers and barrier-breakers among non-users. An online survey was completed by 169 computer users (aged 50+). Analyses revealed that a sizable minority (37%) of participants use online health management tools and most users (89%) are satisfied with these tools, but a limited range of tools are being used and usage occurs in relatively limited domains. Improved awareness and education for online health management tools could enhance people's abilities to remain at home as they age, reducing the financial burden on formal assistance programs. © The Author(s) 2014.

Self-constrained inversion of microgravity data along a segment of the Irpinia fault

NASA Astrophysics Data System (ADS)

Lo Re, Davide; Florio, Giovanni; Ferranti, Luigi; Ialongo, Simone; Castiello, Gabriella

2016-01-01

A microgravity survey was completed to precisely locate and better characterize the near-surface geometry of a recent fault with small throw in a mountainous area in the Southern Apennines (Italy). The site is on a segment of the Irpinia fault, which is the source of the M6.9 1980 earthquake. This fault cuts a few meter of Mesozoic carbonate bedrock and its younger, mostly Holocene continental deposits cover. The amplitude of the complete Bouguer anomaly along two profiles across the fault is about 50 μGal. The data were analyzed and interpreted according to a self-constrained strategy, where some rapid estimation of source parameters was later used as constraint for the inversion. The fault has been clearly identified and localized in its horizontal position and depth. Interesting features in the overburden have been identified and their interpretation has allowed us to estimate the fault slip-rate, which is consistent with independent geological estimates.

Borehole hydraulic coal mining system analysis

NASA Technical Reports Server (NTRS)

Floyd, E. L.

1977-01-01

The borehole hydraulic coal mining system accesses the coal seam through a hole drilled in the overburden. The mining device is lowered through the hole into the coal seam where it fragments the coal with high pressure water jets which pump it to the surface as a slurry by a jet pump located in the center of the mining device. The coal slurry is then injected into a pipeline for transport to the preparation plant. The system was analyzed for performance in the thick, shallow coal seams of Wyoming, and the steeply pitching seams of western Colorado. Considered were all the aspects of the mining operation for a 20-year mine life, producing 2,640,000 tons/yr. Effects on the environment and the cost of restoration, as well as concern for health and safety, were studied. Assumptions for design of the mine, the analytical method, and results of the analysis are detailed.

A search for cosmogenic production of β-neutron emitting radionuclides in water

DOE PAGES

Dazeley, S.; Askins, M.; Bergevin, M.; ...

2016-03-08

Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of β-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the β-neutron measurement, we also provide a first look at isolating single-β producing radionuclides following muon-induced hadronic showers as a check of the detection capabilities of WATCHBOY. The data taken over 207 live days indicates a 9Li production yield upper limit ofmore » $$1.9\\times10^{-7}\\mu^{-1}g^{-1}\\mathrm{cm}^2$$ at $$\\sim400$$ meters water equivalent (m.w.e.) overburden at the 90% confidence level. In this work the 9Li signal in WATCHBOY was used as a proxy for the combined search for 9Li and 8He production. This result will provide a constraint on estimates of antineutrino-like backgrounds in future water-based antineutrino detectors.« less

Secondary migration and leakage of methane from a major tight-gas system

PubMed Central

Wood, James M.; Sanei, Hamed

2016-01-01

Tight-gas and shale-gas systems can undergo significant depressurization during basin uplift and erosion of overburden due primarily to the natural leakage of hydrocarbon fluids. To date, geologic factors governing hydrocarbon leakage from such systems are poorly documented and understood. Here we show, in a study of produced natural gas from 1,907 petroleum wells drilled into a Triassic tight-gas system in western Canada, that hydrocarbon fluid loss is focused along distinct curvilinear pathways controlled by stratigraphic trends with superior matrix permeability and likely also structural trends with enhanced fracture permeability. Natural gas along these pathways is preferentially enriched in methane because of selective secondary migration and phase separation processes. The leakage and secondary migration of thermogenic methane to surficial strata is part of an ongoing carbon cycle in which organic carbon in the deep sedimentary basin transforms into methane, and ultimately reaches the near-surface groundwater and atmosphere. PMID:27874012

[Focal Point “Reading Animal”. Hermann Cohn and the Emergence of the Fin de Siècle Hygiene of Reading].

PubMed

Grütter, Fabian

2015-12-01

From the 1860s onward, ‘eye experts’ increasingly fretted the alleged surge of myopia attributed to an increase of reading matter circulating in schools. In order to avert the inauspicious prospects, revised school desks designed to prevent children from becoming myopic were introduced. During the 1880s, said experts turned to printed matter, maintaining that books must become more reader friendly. Along with the turn to books, a peculiar shift within the hygiene discourse occurred: While the ill addressed by school desk-revisions was myopia, the goal of revising book design was to make reading less tiring. This paper explores both the shift from the hygiene of the eye to the hygiene of reading as well as the materialization of the stipulations and claims made by reading hygienists. In doing so, the paper demonstrates that optimizing the reading process was closely linked to a fear of overburdening and fatigue which expressed itself in the psychopathological discourse of the time.

Methane seeps along boundaries of arctic permafrost thaw and melting glaciers

NASA Astrophysics Data System (ADS)

Anthony, P.; Walter Anthony, K. M.; Grosse, G.; Chanton, J.

2014-12-01

Methane, a potent greenhouse gas, accumulates in subsurface hydrocarbon reservoirs. In the Arctic, impermeable icy permafrost and glacial overburden form a 'cryosphere cap' that traps gas leaking from these reservoirs, restricting flow to the atmosphere. We document the release of geologic methane to the atmosphere from abundant gas seeps concentrated along boundaries of permafrost thaw and receding glaciers in Alaska. Through aerial and ground surveys we mapped >150,000 seeps identified as bubbling-induced open holes in lake ice. Subcap methane seeps had anomalously high fluxes, 14C-depletion, and stable isotope values matching known coalbed and thermogenic methane accumulations in Alaska. Additionally, we observed younger subcap methane seeps in Greenland that were associated with ice-sheet retreat since the Little Ice Age. These correlations suggest that in a warming climate, continued disintegration of permafrost, glaciers, and parts of the polar ice sheets will relax pressure on subsurface seals and further open conduits, allowing a transient expulsion of geologic methane currently trapped by the cryosphere cap.

Coal geology of the Bowman-Gascoyne area, Adams, Billings, Bowman, Golden Valley, and Slope counties, North Dakota

USGS Publications Warehouse

Lewis, Robert C.

1979-01-01

The Bowrnan-Gascoyne area is located in southwestern North Dakota. It is situated on the southwestern edge of the Williston structural basin and the northeastern flank of the Cedar Creek anticline. Strata of the Fort Union Formation (Paleocene), consisting of nonmarine claystone, sandstone, and lignite, dip to the northeast 25-50 ft/mi. Seven correlatable coal beds of varying thicknesses and areal dimensions occur in the area. The thickest and most persistent of these beds is the Harmon bed which attains a maximum thickness of 38 ft in T. 134 N., Rs. 101 and 102 W. Analyses show a heating value of 5,915-6,680 Btu/lb and a sulfur content of 0.6-1.4 percent. Two areas of high-coal-development potential are located near Gascoyne and Amidon. The Harmon bed in these two areas contains a total of 740,000,000 and 650,000,000 tons, respectively, and is under less than 150 ft of overburden.

Study of Internal Dump Stability of Dudhichua Open Cast Project, Northern Coalfields Limited, India

NASA Astrophysics Data System (ADS)

Sengupta, S.; Roy, I.

2015-04-01

Dudhichua Open Cast Project is one of the prestigious projects of Northern Coalfields Limited, India; with total mineable coal reserves of approximately 400 million tonnes and corresponding 1,700 million m3 volume of waste rock i.e. overburden material. Accommodating this waste dump masses in the limited space of the de-coaled portion of the quarry is considered as one of the major challenges to the mine operators. It has been reported that this mine is facing frequent slope failures of waste rock dumps which is of great concern to the mine management in view of unsafe working condition. To tackle the above problem, a detailed investigation was carried out to propose a stable dump profile which will cater to the land economics and safety aspects of the mine. A detailed investigation along with recommendation of optimum design for dragline dump profile along with shovel-dumper-dump profile is presented in this paper.

Physics capabilities of the SNO+ experiment

NASA Astrophysics Data System (ADS)

Arushanova, E.; Back, A. R.; SNO+ Collaboration

2017-09-01

SNO+ will soon enter its first phase of physics data-taking. The Canadian-based detector forms part of the SNOLAB underground facility, in a Sudbury nickel mine; its location providing more than two kilometres of rock overburden. We present an overview of the SNO+ experiment and its physics capabilities. Our primary goal is the search for neutrinoless double-beta decay, where our expected sensitivity would place an upper limit of 1.9 × 1026 y, at 90% CL, on the half-life of neutrinoless double-beta decay in 130Te. We also intend to build on the success of SNO by studying the solar neutrino spectrum. In the unloaded scintillator phase SNO+ has the ability to make precision measurements of the fluxes of low-energy pep neutrinos and neutrinos from the CNO cycle. Other physics goals include: determining the spectrum of reactor antineutrinos, to further constrain Δ {m}122; detecting neutrinos produced by a galactic supernova and investigating certain modes of nucleon decay.

Exploratory Retrospective Analysis of Power Plant Emissions in Vulnerable Communities in the United States

NASA Astrophysics Data System (ADS)

Declet-Barreto, J.; Pham, M.

2016-12-01

Carbon emissions trading has been implemented in parts of the United States (and elsewhere) to reduce greenhouse gas emissions. Data from one such program focused on power plant emissions in the U.S. Northeast and Mid-Atlantic, the Regional Greenhouse Gas Initiative (RGGI), have shown that regionally, power sector carbon dioxide emissions have been reduced since the adoption of the program in 2009. However, it is not known what the spatial distributions of such reductions have been in individual plants, and if emissions reductions have ocurred in plants impacting low-income and ethnic minority communities, arguably the populations most overburdened by health threats from co-pollutants (e.g., fine particulates, nitrous oxides, and sulfurous oxides) emitted along greenhouse gases. In this research, we explore the trajectory of power plant emissions in the RGGI region in vulnerable communities. This is a first, exploratory step in understanding the environmental justice implications of market-based carbon reduction policies.

Where is the "W"oman in MCH?

PubMed

Atrash, Hani; Jack, Brian W; Johnson, Kay; Coonrod, Dean V; Moos, Merry-K; Stubblefield, Phillip G; Cefalo, Robert; Damus, Karla; Reddy, Uma M

2008-12-01

Scientific evidence indicates that improving a woman's health before pregnancy will improve pregnancy outcomes. However, for many years, our efforts have focused primarily on prenatal care and on caring for infants after birth. The concept of preconception care has been identified repeatedly as a priority for improving maternal and infant health. Preconception care is not something new that is being added to the already overburdened healthcare provider, but it is a part of routine primary care for women of reproductive age. Many opportunities exist for preconception intervention, and much of preconception care involves merely the provider reframing his or her thinking, counseling, and decisions in light of the reproductive plans and sexual and contraceptive practices of the patient. With existing scientific evidence that improving the health of "W"omen will improve the health of mothers and children, we must focus on improving the health of "W"omen before pregnancy and put the "W" in Maternal and Child Health.

[Disease prevention in the elderly: misconceptions in current models].

PubMed

Veras, Renato Peixoto

2012-10-01

The Brazilian population is aging significantly within a context of gradual improvement in the country's social and economic indicators. Increased longevity leads to increased use of health services, pressuring the public and social welfare health services, generating higher costs, and jeopardizing the system's sustainability. The alternative to avoid overburdening the system is to invest in policies for disease prevention, stabilization of chronic diseases, and maintenance of functional capacity. The current article aims to analyze the difficulties in implementing preventive programs and the reasons for the failure of various programs in health promotion, prevention, and management of chronic diseases in the elderly. There can be no solution to the crisis in financing and restructuring the health sector without implementing a preventive logic. Scientific research has already correctly identified the risk factors for the elderly population, but this is not enough. We must use such knowledge to promote the necessary transition from a healthcare-centered model to a preventive one.

The use of socially assistive robots for dementia care.

PubMed

Huschilt, Julie; Clune, Laurie

2012-10-01

Innovative solutions for dementia care are required to address the steady rise in adults living with dementia, lack of adequate staffing to provide high-quality dementia care, and the need for family caregivers to provide care for their loved ones in the home. This article provides an overview of the use of socially assistive robots (SARs) to offer support as therapists, companions, and educators for people living with dementia. Social, ethical, and legal challenges associated with the use of robotic technology in patient care and implications for the use of SARs by nurses are discussed. These items considered, the authors conclude that SARs should be considered as a viable way to assist people living with dementia to maintain their highest possible level of independence, enhance their quality of life, and provide support to overburdened family caregivers. Further research is needed to evaluate the merits of this technological approach in the care of adults with dementia. Copyright 2012, SLACK Incorporated.

Pimienta-Tamabra(!) - A giant supercharged petroleum system in the southern Gulf of Mexico, onshore and offshore Mexico

USGS Publications Warehouse

Magoon, L.B.; Hudson, T.L.; Cook, H.E.

2001-01-01

Pimienta-Tamabra(!) is a giant supercharged petroleum system in the southern Gulf of Mexico with cumulative production and total reserves of 66.3 billion barrels of oil and 103.7 tcf of natural gas, or 83.6 billion barrels of oil equivalent (BOE). The effectiveness of this system results largely from the widespread distribution of good to excellent thermally mature, Upper Jurassic source rock underlying numerous stratigraphic and structural traps that contain excellent carbonate reservoirs. Expulsion of oil and gas as a supercritical fluid from Upper Jurassic source rock occurred when the thickness of overburden rock exceeded 5 km. This burial event started in the Eocene, culminated in the Miocene, and continues to a lesser extent today. The expelled hydrocarbons started migrating laterally and then upward as a gas-saturated 35-40??API oil with less than 1 wt.% sulfur and a gas-to-oil ratio (GOR) of 500-1000 ft3/BO. The generation-accumulation efficiency is about 6%.

Analysis of the flow, thermal and geomechanical behavior of offshore hydrate deposits at the NGHP-02-09-A site during short- and long-term gas production scenarios

NASA Astrophysics Data System (ADS)

Moridis, G. J.; Reagan, M. T.; Queiruga, A. F.

2017-12-01

We analyze the gas production potential of recently discovered offshore hydrate deposits at the NGHP-02-09-A sSite in the Krishna-Godawari Basin of India, and the corresponding geomechanical system response during short- and long-term production. Using the most current data on the flow and geomechanical properties of the hydrate-bearing media and of the overburden, as well as information on the system boundaries, we investigate (a) the production rates of gas (CH4) and of water, their relative magnitudes and the reservoir thermal behavior in an effort to assess the viability of these deposits as energy sources, as well as (b) the potential subsidence and the effect of changing pressure and stress regimes on the porosity and permeability (and, consequently, on production). Additionally, we conduct a thorough sensitivity analysis in order to determine (a) the properties and conditions that control and dominate the system behavior, and (b) the range of the possible system response to production.

Search for Ultra-High-Energy Neutrinos with AMANDA-II

NASA Astrophysics Data System (ADS)

Ackermann, M.; Adams, J.; Ahrens, J.; Andeen, K.; Auffenberg, J.; Bai, X.; Baret, B.; Barwick, S. W.; Bay, R.; Beattie, K.; Becka, T.; Becker, J. K.; Becker, K.-H.; Beimforde, M.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Blaufuss, E.; Boersma, D. J.; Bohm, C.; Bolmont, J.; Böser, S.; Botner, O.; Bouchta, A.; Braun, J.; Burgess, T.; Castermans, T.; Chirkin, D.; Christy, B.; Clem, J.; Cowen, D. F.; D'Agostino, M. V.; Davour, A.; Day, C. T.; De Clercq, C.; Demirörs, L.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; DeYoung, T.; Diaz-Velez, J. C.; Dreyer, J.; Dumm, J. P.; Duvoort, M. R.; Edwards, W. R.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Filimonov, K.; Finley, C.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Ganugapati, R.; Geenen, H.; Gerhardt, L.; Goldschmidt, A.; Goodman, J. A.; Gozzini, R.; Griesel, T.; Groß, A.; Grullon, S.; Gunasingha, R. M.; Gurtner, M.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Hardtke, D.; Hardtke, R.; Hasegawa, Y.; Hauschildt, T.; Heise, J.; Helbing, K.; Hellwig, M.; Herquet, P.; Hill, G. C.; Hodges, J.; Hoffman, K. D.; Hommez, B.; Hoshina, K.; Hubert, D.; Hughey, B.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hundertmark, S.; Inaba, M.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kawai, H.; Kelley, J. L.; Kiryluk, J.; Kislat, F.; Kitamura, N.; Klein, S. R.; Klepser, S.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kuehn, K.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Lauer, R.; Leich, H.; Leier, D.; Liubarsky, I.; Lundberg, J.; Lünemann, J.; Madsen, J.; Maruyama, R.; Mase, K.; Matis, H. S.; McCauley, T.; McParland, C. P.; Meagher, K.; Meli, A.; Messarius, T.; Mészáros, P.; Miyamoto, H.; Montaruli, T.; Morey, A.; Morse, R.; Movit, S. M.; Münich, K.; Nahnhauer, R.; Nam, J. W.; Nießen, P.; Nygren, D. R.; Olivas, A.; Ono, M.; Patton, S.; Pérez de los Heros, C.; Piegsa, A.; Pieloth, D.; Pohl, A. C.; Porrata, R.; Pretz, J.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Razzaque, S.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Robbins, S.; Robbins, W. J.; Roth, P.; Rothmaier, F.; Rott, C.; Roucelle, C.; Rutledge, D.; Ryckbosch, D.; Sander, H.-G.; Sarkar, S.; Satalecka, K.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Schultz, O.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Smith, A. J.; Song, C.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stezelberger, T.; Stokstad, R. G.; Stoufer, M. C.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Sulanke, K.-H.; Sullivan, G. W.; Sumner, T. J.; Swillens, Q.; Taboada, I.; Tarasova, O.; Tepe, A.; Thollander, L.; Tilav, S.; Tluczykont, M.; Toale, P. A.; Tosi, D.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; Van Overloop, A.; Viscomi, V.; Vogt, C.; Voigt, B.; Wagner, W.; Walck, C.; Waldmann, H.; Waldenmaier, T.; Walter, M.; Wang, Y.-R.; Wendt, C.; Wiebusch, C. H.; Wiedemann, C.; Wikström, G.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Xu, X. W.; Yodh, G.; Yoshida, S.; Zornoza, J. D.; IceCube Collaboration

2008-03-01

A search for diffuse neutrinos with energies in excess of 105 GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 107 GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra-high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E2Φ90% CL < 2.7 × 10-7 GeV cm-2 s-1 sr-1 valid over the energy range of 2 × 105 to 109 GeV. A number of models that predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.

Strain Measurements of Chondrules and Refraction Inclusion in Allende

NASA Technical Reports Server (NTRS)

Tait, Alastair W.; Fisher, Kent R.; Simon, Justin I.

2013-01-01

This study uses traditional strain measurement techniques, combined with X-ray computerized tomography (CT), to evaluate petrographic evidence in the Allende CV3 chondrite for preferred orientation and to measure strain in three dimensions. The existence of petrofabrics and lineations was first observed in carbonaceous meteorites in the 1960's. Yet, fifty years later only a few studies have reported that meteorites record such features. Impacts are often cited as the mechanism for this feature, although plastic deformation from overburden and nebular imbrication have also been proposed. Previous work conducted on the Leoville CV3 and the Parnallee LL3 chondrites, exhibited a minimum uniaxial shortening of 33% and 21%, respectively. Petrofabrics in Allende CV3 have been looked at before; previous workers using Electron Back Scatter Diffraction (EBSD) found a major-axis alignment of olivine inside dark inclusions and an "augen"-like preferred orientation of olivine grains around more competent chondrules

Compaction and sedimentary basin analysis on Mars

NASA Astrophysics Data System (ADS)

Gabasova, Leila R.; Kite, Edwin S.

2018-03-01

Many of the sedimentary basins of Mars show patterns of faults and off-horizontal layers that, if correctly understood, could serve as a key to basin history. Sediment compaction is a possible cause of these patterns. We quantified the possible role of differential sediment compaction for two Martian sedimentary basins: the sediment fill of Gunjur crater (which shows concentric graben), and the sediment fill of Gale crater (which shows outward-dipping layers). We assume that basement topography for these craters is similar to the present-day topography of complex craters that lack sediment infill. For Gunjur, we find that differential compaction produces maximum strains consistent with the locations of observed graben. For Gale, we were able to approximately reproduce the observed layer orientations measured from orbiter image-based digital terrain models, but only with a >3 km-thick donut-shaped past overburden. It is not immediately obvious what geologic processes could produce this shape.

An Introduction to Using Surface Geophysics to Characterize Sand and Gravel Deposits

USGS Publications Warehouse

Lucius, Jeffrey E.; Langer, William H.; Ellefsen, Karl J.

2006-01-01

This report is an introduction to surface geophysical techniques that aggregate producers can use to characterize known deposits of sand and gravel. Five well-established and well-tested geophysical methods are presented: seismic refraction and reflection, resistivity, ground penetrating radar, time-domain electromagnetism, and frequency-domain electromagnetism. Depending on site conditions and the selected method(s), geophysical surveys can provide information concerning aerial extent and thickness of the deposit, thickness of overburden, depth to the water table, critical geologic contacts, and location and correlation of geologic features. In addition, geophysical surveys can be conducted prior to intensive drilling to help locate auger or drill holes, reduce the number of drill holes required, calculate stripping ratios to help manage mining costs, and provide continuity between sampling sites to upgrade the confidence of reserve calculations from probable reserves to proved reserves. Perhaps the greatest value of geophysics to aggregate producers may be the speed of data acquisition, reduced overall costs, and improved subsurface characterization.

An Introduction to Using Surface Geophysics to Characterize Sand and Gravel Deposits

USGS Publications Warehouse

Lucius, Jeffrey E.; Langer, William H.; Ellefsen, Karl J.

2007-01-01

This report is an introduction to surface geophysical techniques that aggregate producers can use to characterize known deposits of sand and gravel. Five well-established and well-tested geophysical methods are presented: seismic refraction and reflection, resistivity, ground penetrating radar, time-domain electromagnetism, and frequency-domain electromagnetism. Depending on site conditions and the selected method(s), geophysical surveys can provide information concerning areal extent and thickness of the deposit, thickness of overburden, depth to the water table, critical geologic contacts, and location and correlation of geologic features. In addition, geophysical surveys can be conducted prior to intensive drilling to help locate auger or drill holes, reduce the number of drill holes required, calculate stripping ratios to help manage mining costs, and provide continuity between sampling sites to upgrade the confidence of reserve calculations from probable reserves to proved reserves. Perhaps the greatest value of geophysics to aggregate producers may be the speed of data acquisition, reduced overall costs, and improved subsurface characterization.

Global Characteristics of Porosity and Density Stratification Within the Lunar Crust from GRAIL Gravity and Lunar Orbiter Laser Altimeter Topography Data

NASA Technical Reports Server (NTRS)

Han, Shin-Chan; Schmerr, Nicholas; Neumann, Gregory; Holmes, Simon

2014-01-01

The Gravity Recovery and Interior Laboratory (GRAIL) mission is providing unprecedentedly high-resolution gravity data. The gravity signal in relation to topography decreases from 100 km to 30 km wavelength, equivalent to a uniform crustal density of 2450 kg/cu m that is 100 kg/cu m smaller than the density required at 100 km. To explain such frequency-dependent behavior, we introduce rock compaction models under lithostatic pressure that yield radially stratified porosity (and thus density) and examine the depth extent of porosity. Our modeling and analysis support the assertion that the crustal density must vary from surface to deep crust by up to 500 kg/cu m. We found that the surface density of mega regolith is around 2400 kg/cu m with an initial porosity of 10-20%, and this porosity is eliminated at 10-20 km depth due to lithostatic overburden pressure. Our stratified density models provide improved fits to both GRAIL primary and extended mission data.

A study on off-fault aftershock pattern at N-Adria microplate

NASA Astrophysics Data System (ADS)

Bressan, Gianni; Barnaba, Carla; Magrin, Andrea; Rossi, Giuliana

2018-03-01

The spatial features of the aftershock sequences triggered by three moderate magnitude events with coda-duration magnitudes 4.1, 5.1 and 5.6, which occurred in Northeastern Italy and Western Slovenia, were investigated. The fractal dimension and the orientations of the planar features fitting the hypocentral data have been inferred. The spatial organization is articulated through two temporal phases. The first phase is characterized by the decreasing of the fractal dimension and by vertically oriented planes fitting the hypocentral foci. The second phase is marked by an increase of the fractal dimension and by the activation of different planes, with more widespread orientation. The aftershock temporal distribution is analysed with a model based on a static fatigue process. The process is favoured by the decrease of the overburden pressure, the sharp variations of the mechanical properties of the medium and the unclamping effect resulting from positive normal stress changes caused by the mainshock stress step.

Cooperative medical insurance and the cost of care in Shandong, PR China: perspectives of patients and community members.

PubMed

Mahmood, Mohammad Afzal; Raulli, Alexandra; Yan, Wang; Dong, Han; Aiguo, Zhang; Ping, Dong

2015-03-01

This research was conducted to identify the cost of care associated with utilization of village clinics and membership of the New Cooperative Medical Scheme (NCMS) in 2 counties of Shandong province, PR China. A total of 397 community members and 297 patients who used the village clinics were interviewed. The average cost for primary care treatment of 1 episode of illness was about 55 yuan (about US$8). Although more than 50% of people had NCMS membership, many consider the monetary reimbursements as insufficient. The low insurance reimbursement rates and inability to pay out-of-pocket expenses compromise access to care. Delays can cause more serious illnesses with potential to overburden the secondary care at the township and county hospitals. Those rural people who have not yet enjoyed the benefits of China's economic development may not benefit from recent health care reform and finance mechanisms unless schemes such as the NCMS provide more substantial subsidies. © 2010 APJPH.

On how whales avoid decompression sickness and why they sometimes strand.

PubMed

Blix, Arnoldus Schytte; Walløe, Lars; Messelt, Edward B

2013-09-15

Whales are unique in that the supply of blood to the brain is not by the internal carotid arteries, but by way of thoracic and intra-vertebral arterial retia. We found in the harbor porpoise (Phocoena phocoena) that these retia split up into smaller anastomosing vessels and thin-walled sinusoid structures that are embedded in fat. The solubility of nitrogen is at least six times larger in fat than in water, and we suggest that nitrogen in supersaturated blood will be absorbed in the fat, by diffusion, during the very slow passage of the blood through the arterial retia. Formation of nitrogen bubbles that may reach the brain is thereby avoided. We also suggest that mass stranding of whales may be due to disturbances to their normal dive profiles, resulting in extra release of nitrogen that may overburden the nitrogen 'trap' and allow bubbles to reach the brain and cause abnormal behavior.

Identification Of Rippability And Bedrock Depth Using Seismic Refraction

NASA Astrophysics Data System (ADS)

Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M.; Muztaza, Nordiana Mohd; El Hidayah Ismail, Noer; Mohamad, Edy Tonizam

2010-12-01

Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel. The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.

Evaluating bump control techniques through convergence monitoring

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

Campoli, A.A.

1987-07-01

A coal mine bump is the violent failure of a pillar or pillars due to overstress. Retreat coal mining concentrates stresses on the pillars directly outby gob areas, and the situation becomes critical when mining a coalbed encased in rigid associated strata. Bump control techniques employed by the Olga Mine, McDowell County, WV, were evaluated through convergence monitoring in a Bureau of Mines study. Olga uses a novel pillar splitting mining method to extract 55-ft by 70-ft chain pillars, under 1,100 to 1,550 ft of overburden. Three rows of pillars are mined simultaneously to soften the pillar line and reducemore » strain energy storage capacity. Localized stress reduction (destressing) techniques, auger drilling and shot firing, induced approximately 0.1 in. of roof-to-floor convergence in ''high'' -stress pillars near the gob line. Auger drilling of a ''low''-stress pillar located between two barrier pillars produced no convergence effects.« less

Teleretinal Screening for Diabetic Retinopathy in Six Los Angeles Urban Safety-Net Clinics: Initial Findings

PubMed Central

Ogunyemi, Omolola; Terrien, Elizabeth; Eccles, Alicia; Patty, Lauren; George, Sheba; Fish, Allison; Teklehaimanot, Senait; Ilapakurthi, Ramarao; Aimiuwu, Otaren; Baker, Richard

2011-01-01

Diabetic retinopathy is a leading cause of blindness in US adults. This paper presents initial results of a teleretinal screening project for diabetic retinopathy involving six Los Angeles safety net clinics. A total of 1,943 patients have been screened for diabetic retinopathy by three ophthalmologist readers, with 416 receiving a recommendation for referral to specialty care. Of the cases recommended for referral, 24 had proliferative diabetic retinopathy, 62 had severe non-proliferative diabetic retinopathy (NPDR), 60 had moderate NPDR, 19 had mild NPDR, 138 had a non-diabetic condition, such as glaucoma, 63 had clinically significant macular edema without retinopathy and 50 had non-gradable images. Between 3% and 12.2% of retinal images taken at the clinics were assessed by readers as inadequate for any interpretation. The study shows the feasibility and challenges of teleretinal screening for diabetic retinopathy in urban areas facing specialist shortages and an overburdened, under-resourced safety net care-delivery system. PMID:22195163

[Volunteering in psychiatry: determining factors of attitude and actual commitment].

PubMed

Lauber, C; Nordt, C; Falcato, L; Rössler, W

2000-10-01

To assess public attitude, actual working commitment and the respective influence of demographic, psychological and sociological variables on voluntary help in psychiatry. Multiple logistic regression analysis of the results of a representative population survey in Switzerland. Public attitude is mostly positive, but the respective working commitment is small. Attitude depends on gender, psychological factors (social distance, stereotypes), and on attitude to community psychiatry. For the working commitment, clearly distinct predictors are found: age, emotions, participation, and perceived discrimination to the mentally ill. For both attitude and commitment, having a social profession and interest in mass media are predictors. Internationally compared, Switzerland has a positive attitude and a big commitment in lay helping in psychiatry. But attitude is different from actual commitment. Lay helpers' work must be limited to realizable tasks and they need professional recruitment, instruction, and supervision otherwise they tend to be over-burden. The unused potential of voluntary helpers has to be opened specifically, e.g. by involving mass media and opinion-makers.

Challenges to replicating evidence-based research in real-world settings: training African-American peers as patient navigators for colon cancer screening.

PubMed

Sly, Jamilia R; Jandorf, Lina; Dhulkifl, Rayhana; Hall, Diana; Edwards, Tiffany; Goodman, Adam J; Maysonet, Elithea; Azeez, Sulaiman

2012-12-01

Many cancer-prevention interventions have demonstrated effectiveness in diverse populations, but these evidenced-based findings slowly disseminate into practice. The current study describes the process of disseminating and replicating research (i.e., peer patient navigation for colonoscopy screening) in real-world settings. Two large metropolitan hospitals collaborated to replicate a peer patient navigation model within their existing navigation systems. Six African-American peer volunteers were recruited and trained to navigate patients through colonoscopy scheduling and completion. Major challenges included: (1) operating within multiple institutional settings; (2) operating within nonacademic/research infrastructures; (3) integrating into an established navigation system; (4) obtaining support of hospital staff without overburdening; and (5) competing priorities and time commitments. Bridging the gap between evidence-based research and practice is critical to eliminating many cancer health disparities; therefore, it is crucial that researchers and practitioners continue to work to achieve both diffusion and fusion of evidence-based findings. Recommendations for addressing these challenges are discussed.

State obligations to implement African abortion laws: employing human rights in a changing legal landscape.

PubMed

Ngwena, Charles G

2012-11-01

Women in the African region are overburdened with unsafe abortion. Abortion regimes that fail to translate any given abortion rights into tangible access are partly to blame. Historically, African abortion laws have been highly restrictive. However, the post-independence era has witnessed a change toward liberalizing abortion law, even if incremental for many jurisdictions. Furthermore, Article 14 of the Protocol to the African Charter on Human and Peoples' Rights on the Rights of Women in Africa has significantly augmented the regional trend toward liberalization by recognizing abortion as a human right in given circumstances. However, states are failing to implement abortion laws. The jurisprudence that is emerging from the European Court of Human Rights and United Nations treaty bodies is a tool that can be used to render African governments accountable for failure to implement domestic abortion laws. Copyright © 2012 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Frustules to fragments, diatoms to dust: How degradation of microfossil shape and microstructures can teach us how ice sheets work

USGS Publications Warehouse

Scherer, R.P.; Sjunneskog, C.M.; Iverson, M.R.; Hooyer, T.S.

2005-01-01

In a laboratory experiment we investigated micro- and nanoscale changes in fossil diatom valves and in the texture of diatomaceous sediments that result from ice sheet overburden and subglacial shearing. Our experiment included compression and shearing of Antarctic diatom-rich sediments in a ring shear device and comparison of experimental samples with natural glacial sediments from the Antarctic continental shelf. The purpose of the experiment is to establish objective criteria for analyzing subglacial processes and interpreting the origin of glacial-geologic features on the Antarctic continental shelf. We find distinct changes resulting from different glacial settings, with respect to whole diatom frustules, diatom micromorphology, and microtextural properties of sedimentary units. By providing constraints on subglacial shearing, these observations of genetically controlled micro- and nanoscale diatom structures and architecture are contributing to the understanding of large-scale glacial processes, aiding the development of models of modern ice sheet processes, and guiding interpretation of past ice sheet configurations. Copyright ?? 2005 American Scientific Publishers. All rights reserved.

Performance of an optical relay satellite using Reed-Solomon coding over a cascaded optical PPM and BPSK channel

NASA Technical Reports Server (NTRS)

Divsalar, D.; Naderi, F.

1982-01-01

The nature of the optical/microwave interface aboard the relay satellite is considered. To allow for the maximum system flexibility, without overburdening either the optical or RF channel, demodulating the optical on board the relay satellite but leaving the optical channel decoding to be performed at the ground station is examined. The occurrence of erasures in the optical channel is treated. A hard decision on the erasure (i.e., the relay selecting a symbol at random in case of erasure occurrence) seriously degrades the performance of the overall system. Coding the erasure occurrences at the relay and transmitting this information via an extra bit to the ground station where it can be used by the decoder is suggested. Many examples with varying bit/photon energy efficiency and for the noisy and noiseless optical channel are considered. It is shown that coding the erasure occurrences dramatically improves the performance of the cascaded channel relative to the case of hard decision on the erasure by the relay.

Alaskan North Slope petroleum systems

USGS Publications Warehouse

Magoon, L.B.; Lillis, P.G.; Bird, K.J.; Lampe, C.; Peters, K.E.

2003-01-01

Six North Slope petroleum systems are identified, described, and mapped using oil-to-oil and oil-to-source rock correlations, pods of active source rock, and overburden rock packages. To map these systems, we assumed that: a) petroleum source rocks contain 3.2 wt. % organic carbon (TOC); b) immature oil-prone source rocks have hydrogen indices (HI) >300 (mg HC/gm TOC); c) the top and bottom of the petroleum (oil plus gas) window occur at vitrinite reflectance values of 0.6 and 1.0% Ro, respectively; and d) most hydrocarbons are expelled within the petroleum window. The six petroleum systems we have identified and mapped are: a) a southern system involving the Kuna-Lisburne source rock unit that was active during the Late Jurassic and Early Cretaceous; b) two western systems involving source rock in the Kingak-Blankenship, and GRZ-lower Torok source rock units that were active during the Albian; and c) three eastern systems involving the Shublik-Otuk, Hue Shale and Canning source rock units that were active during the Cenozoic. The GRZ-lower Torok in the west is correlative with the Hue Shale to the east. Four overburden rock packages controlled the time of expulsion and gross geometry of migration paths: a) a southern package of Early Cretaceous and older rocks structurally-thickened by early Brooks Range thrusting; b) a western package of Early Cretaceous rocks that filled the western part of the foreland basin; c) an eastern package of Late Cretaceous and Paleogene rocks that filled the eastern part of the foreland basin; and d) an offshore deltaic package of Neogene rocks deposited by the Colville, Canning, and Mackenzie rivers. This petroleum system poster is part of a series of Northern Alaska posters on modeling. The poster in this session by Saltus and Bird present gridded maps for the greater Northern Alaskan onshore and offshore that are used in the 3D modeling poster by Lampe and others. Posters on source rock units are by Keller and Bird as well as

Long-lived sediment dispersal pathways of the U.S. Cordillera in southwest Montana: Evidence from Paleogene intermontane basin deposits and relationship to regional structure

NASA Astrophysics Data System (ADS)

Weislogel, A. L.; Schwartz, R.; Rothfuss, J. L.; Schwartz, T.

2010-12-01

Inherited topography and basement crustal infrastructure associated with Sevier-Laramide orogenesis played a major role in the fluvial sculpting of intermontane-scale paleovalleys that served as precursors to the modern intermontane basins and existing drainage network. Paleocurrent, facies and detrital zircon and petrologic provenance data indicate that Upper Eocene-Lower Miocene units in the Renova Fm. mark the transition from fluvial incision to sediment backfilling of long-lived, paleovalley systems. Paleo-alluvial systems carried Renova detritus shed from high-relief (>2 km) early Paleogene highlands that originated as Sevier-Laramide uplifts and persist today as modern highlands. Detrital zircon and clast composition data indicate the Boulder and Tobacco Roots batholiths were widely unroofed, and plutons in the Anaconda range and Idaho batholith were at least partially unroofed. Renova sediment was routed by a recurved trellis-like fluvial trunk system that generally paralleled the track of river systems occupying the modern intermontaine basins. In most areas, geometry of these pathways are demonstrably linked to structural grain of the underlying Sevier-Laramide orogen and may have been modified by later extensional reactivation. Renova paleodrainage configuration bears resemblance to sediment pathways identified in the Cretaceous Kootenai, Blackleaf, and Frontier formations and Beaverhead Group. Detrital remnants of the substantial volume of Elkhorn Mountain volcanic rock and Paleozoic-Mesozoic sedimentary rock overburden are rare within Renova deposits indicating that batholith overburden was exported out of the system in the >20 m.y. duration between the end of the Cretaceous and beginning of widespread Renova deposition. Thus, significant mass was transferred from a segment the Sevier-Laramide orogenic highlands and routed via an ancestral drainage network to a sink that lies several hundreds of kilometers away and along strike of the prevailing

Numerical modeling of fracking fluid and methane migration through fault zones in shale gas reservoirs

NASA Astrophysics Data System (ADS)

Taherdangkoo, Reza; Tatomir, Alexandru; Sauter, Martin

2017-04-01

Hydraulic fracturing operation in shale gas reservoir has gained growing interest over the last few years. Groundwater contamination is one of the most important environmental concerns that have emerged surrounding shale gas development (Reagan et al., 2015). The potential impacts of hydraulic fracturing could be studied through the possible pathways for subsurface migration of contaminants towards overlying aquifers (Kissinger et al., 2013; Myers, 2012). The intent of this study is to investigate, by means of numerical simulation, two failure scenarios which are based on the presence of a fault zone that penetrates the full thickness of overburden and connect shale gas reservoir to aquifer. Scenario 1 addresses the potential transport of fracturing fluid from the shale into the subsurface. This scenario was modeled with COMSOL Multiphysics software. Scenario 2 deals with the leakage of methane from the reservoir into the overburden. The numerical modeling of this scenario was implemented in DuMux (free and open-source software), discrete fracture model (DFM) simulator (Tatomir, 2012). The modeling results are used to evaluate the influence of several important parameters (reservoir pressure, aquifer-reservoir separation thickness, fault zone inclination, porosity, permeability, etc.) that could affect the fluid transport through the fault zone. Furthermore, we determined the main transport mechanisms and circumstances in which would allow frack fluid or methane migrate through the fault zone into geological layers. The results show that presence of a conductive fault could reduce the contaminant travel time and a significant contaminant leakage, under certain hydraulic conditions, is most likely to occur. Bibliography Kissinger, A., Helmig, R., Ebigbo, A., Class, H., Lange, T., Sauter, M., Heitfeld, M., Klünker, J., Jahnke, W., 2013. Hydraulic fracturing in unconventional gas reservoirs: risks in the geological system, part 2. Environ Earth Sci 70, 3855

Differential subsidence and its effect on subsurface infrastructure: predicting probability of pipeline failure (STOOP project)

NASA Astrophysics Data System (ADS)

de Bruijn, Renée; Dabekaussen, Willem; Hijma, Marc; Wiersma, Ane; Abspoel-Bukman, Linda; Boeije, Remco; Courage, Wim; van der Geest, Johan; Hamburg, Marc; Harmsma, Edwin; Helmholt, Kristian; van den Heuvel, Frank; Kruse, Henk; Langius, Erik; Lazovik, Elena

2017-04-01

Due to heterogeneity of the subsurface in the delta environment of the Netherlands, differential subsidence over short distances results in tension and subsequent wear of subsurface infrastructure, such as water and gas pipelines. Due to uncertainties in the build-up of the subsurface, however, it is unknown where this problem is the most prominent. This is a problem for asset managers deciding when a pipeline needs replacement: damaged pipelines endanger security of supply and pose a significant threat to safety, yet premature replacement raises needless expenses. In both cases, costs - financial or other - are high. Therefore, an interdisciplinary research team of geotechnicians, geologists and Big Data engineers from research institutes TNO, Deltares and SkyGeo developed a stochastic model to predict differential subsidence and the probability of consequent pipeline failure on a (sub-)street level. In this project pipeline data from company databases is combined with a stochastic geological model and information on (historical) groundwater levels and overburden material. Probability of pipeline failure is modelled by a coupling with a subsidence model and two separate models on pipeline behaviour under stress, using a probabilistic approach. The total length of pipelines (approx. 200.000 km operational in the Netherlands) and the complexity of the model chain that is needed to calculate a chance of failure, results in large computational challenges, as it requires massive evaluation of possible scenarios to reach the required level of confidence. To cope with this, a scalable computational infrastructure has been developed, composing a model workflow in which components have a heterogeneous technological basis. Three pilot areas covering an urban, a rural and a mixed environment, characterised by different groundwater-management strategies and different overburden histories, are used to evaluate the differences in subsidence and uncertainties that come with

Comparison of humus and till as prospecting material in areas of thick overburden and multiple ice-flow events: An example from northeastern New Brunswick

USGS Publications Warehouse

Broster, Bruce E.; Dickson, M.L.; Parkhill, M.A.

2009-01-01

Thirty-nine elements in humus and till matrix were compared at 109 sites overlying Ag-As-Cu-Mo-Pb-Zn mineralized occurrences in northeastern New Brunswick to assess humus for anomaly identification. Humus element concentrations were not consistently correlative with maximum or minimum concentrations found in the underlying till or bedrock. The humus demonstrated significantly higher mean elemental concentrations than the till for six specific elements: 9 times greater for Mn, 6 times greater for Cd, 5 times greater for Ag and Pb, 3 times greater for Hg, and double the concentration of Zn. Spatial dispersal patterns for these elements were much larger for humus content than that exhibited by the till matrix analysis, but did not delineate a point source. For elements in till, the highest concentrations were commonly found directly overlying the underlying mineralized bedrock source or within one km down-glacier of the source. The complexity of the humus geochemical patterns is attributed to the effects of post-glacial biogenic, down-slope hydrodynamic and solifluction modification of dispersed mineralization in the underlying till, and the greater capacity of humus to adsorb cations and form complexes with some elements, relative to the till matrix. Humus sampling in areas of glaciated terrain is considered to be mostly valuable for reconnaissance exploration as elements can be spatially dispersed over a much larger area than that found in the till or underlying bedrock. ?? 2009 Elsevier B.V. All rights reserved.

Hydrogeologic framework and hydrologic budget components of the Columbia Plateau Regional Aquifer System, Washington, Oregon, and Idaho

USGS Publications Warehouse

Kahle, S.C.; Morgan, D.S.; Welch, W.B.; Ely, D.M.; Hinkle, S.R.; Vaccaro, J.J.; Orzol, L.L.

2011-01-01

The Columbia Plateau Regional Aquifer System (CPRAS) covers an area of about 44,000 square miles in a structural and topographic basin within the drainage of the Columbia River in Washington, Oregon, and Idaho. The primary aquifers are basalts of the Columbia River Basalt Group (CRBG) and overlying sediment. Eighty percent of the groundwater use in the study area is for irrigation, in support of a $6 billion per year agricultural economy. Water-resources issues in the Columbia Plateau include competing agricultural, domestic, and environmental demands. Groundwater levels were measured in 470 wells in 1984 and 2009; water levels declined in 83 percent of the wells, and declines greater than 25 feet were measured in 29 percent of the wells. Conceptually, the system is a series of productive basalt aquifers consisting of permeable interflow zones separated by less permeable flow interiors; in places, sedimentary aquifers overly the basalts. The aquifer system of the CPRAS includes seven hydrogeologic units-the overburden aquifer, three aquifer units in the permeable basalt rock, two confining units, and a basement confining unit. The overburden aquifer includes alluvial and colluvial valley-fill deposits; the three basalt units are the Saddle Mountains, Wanapum, and Grande Ronde Basalts and their intercalated sediments. The confining units are equivalent to the Saddle Mountains-Wanapum and Wanapum-Grande Ronde interbeds, referred to in this study as the Mabton and Vantage Interbeds, respectively. The basement confining unit, referred to as Older Bedrock, consists of pre-CRBG rocks that generally have much lower permeabilities than the basalts and are considered the base of the regional flow system. Based on specific-capacity data, median horizontal hydraulic conductivity (Kh) values for the overburden, basalt units, and bedrock are 161, 70, and 6 feet per day, respectively. Analysis of oxygen isotopes in water and carbon isotopes in dissolved inorganic carbon from

Ground-water and surface-water flow and estimated water budget for Lake Seminole, southwestern Georgia and northwestern Florida

USGS Publications Warehouse

Dalton, Melinda S.; Aulenbach, Brent T.; Torak, Lynn J.

2004-01-01

Lake Seminole is a 37,600-acre impoundment formed at the confluence of the Flint and Chattahoochee Rivers along the Georgia?Florida State line. Outflow from Lake Seminole through Jim Woodruff Lock and Dam provides headwater to the Apalachicola River, which is a major supply of freshwater, nutrients, and detritus to ecosystems downstream. These rivers,together with their tributaries, are hydraulically connected to karst limestone units that constitute most of the Upper Floridan aquifer and to a chemically weathered residuum of undifferentiated overburden. The ground-water flow system near Lake Seminole consists of the Upper Floridan aquifer and undifferentiated overburden. The aquifer is confined below by low-permeability sediments of the Lisbon Formation and, generally, is semiconfined above by undifferentiated overburden. Ground-water flow within the Upper Floridan aquifer is unconfined or semiconfined and discharges at discrete points by springflow or diffuse leakage into streams and other surface-water bodies. The high degree of connectivity between the Upper Floridan aquifer and surface-water bodies is limited to the upper Eocene Ocala Limestone and younger units that are in contact with streams in the Lake Seminole area. The impoundment of Lake Seminole inundated natural stream channels and other low-lying areas near streams and raised the water-level altitude of the Upper Floridan aquifer near the lake to nearly that of the lake, about 77 feet. Surface-water inflow from the Chattahoochee and Flint Rivers and Spring Creek and outflow to the Apalachicola River through Jim Woodruff Lock and Dam dominate the water budget for Lake Seminole. About 81 percent of the total water-budget inflow consists of surface water; about 18 percent is ground water, and the remaining 1 percent is lake precipitation. Similarly, lake outflow consists of about 89 percent surface water, as flow to the Apalachicola River through Jim Woodruff Lock and Dam, about 4 percent ground water

Player Modeling for Intelligent Difficulty Adjustment

NASA Astrophysics Data System (ADS)

Missura, Olana; Gärtner, Thomas

In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

Activity-based exploitation of Full Motion Video (FMV)

NASA Astrophysics Data System (ADS)

Kant, Shashi

2012-06-01

Video has been a game-changer in how US forces are able to find, track and defeat its adversaries. With millions of minutes of video being generated from an increasing number of sensor platforms, the DOD has stated that the rapid increase in video is overwhelming their analysts. The manpower required to view and garner useable information from the flood of video is unaffordable, especially in light of current fiscal restraints. "Search" within full-motion video has traditionally relied on human tagging of content, and video metadata, to provision filtering and locate segments of interest, in the context of analyst query. Our approach utilizes a novel machine-vision based approach to index FMV, using object recognition & tracking, events and activities detection. This approach enables FMV exploitation in real-time, as well as a forensic look-back within archives. This approach can help get the most information out of video sensor collection, help focus the attention of overburdened analysts form connections in activity over time and conserve national fiscal resources in exploiting FMV.

Construction on dolomite in south Africa

NASA Astrophysics Data System (ADS)

Wagener, Fritz Von M.; Day, Peter W.

1986-03-01

Damage to structures and loss of life have been more severe on dolomite than on any other geological formation in southern Africa. The subsidence that occurs on dolomitic terrain following development or during dewatering has given dolomite a notorious reputation and engineers and geologists became reluctant to recommend development on the material. This has led to the pioneering of founding methods for a wide variety of structures aimed at reducing the risk of severity of damage due to subsidence settlement Structures successfully founded on dolomitic terrane include residential and industrial buildings, gold mine reduction works and shaft structures, tailings dams, water retaining structures, and road and rail links. In this article, various methods of construction, some ot which were developed by the authors, are presented. It commences with a classification of a dolomite site in terms of overburden thickness followed by a discussion of the relevant construction methods The methods include mattresses of compacted soil supported by pinnacles or “floating” in residuum, deep foundations such as caissons, the use of specialized piling techniques, and soil improvement by dynamic consolidation

The duty to bring children living in conflict zones to a safe haven

PubMed Central

Schweiger, Gottfried

2016-01-01

ABSTRACT In this paper, I will discuss a children’s rights-based argument for the duty of states, as a joint effort, to establish an effective program to help bring children out of conflict zones, such as parts of Syria, and to a safe haven. Children are among the most vulnerable subjects in violent conflicts who suffer greatly and have their human rights brutally violated as a consequence. Furthermore, children are also a group whose capacities to protect themselves are very limited, while their chance to flee is most often only slim. I will then discuss three counterarguments: the first counterargument would be that, instead of getting the children out of a particular country, it would be better to improve their situation in their home countries. A second counterargument could be that those states, which have such a duty to bring children to a safe haven, would be overburdened by it. Finally, the third counterargument I want to discuss states that such a duty would also demand a military intervention, which could worsen the situation even further. PMID:28690666

Line-Drawing Enhanced Interactive Mural Restoration for Dunhuang Mogao Grottoes

NASA Astrophysics Data System (ADS)

Fu, X. Y.; Han, Y.; Sun, Z. J.; Ma, X. J.; Xu, Y. Q.

2017-08-01

Dunhuang Mogao Grottoes in western China is one of the most famous World Cultural Heritage Sites, known for its glorious Chinese Buddhist art spanning a period of 1,000 years. However, it has been suffering from damage and degradation caused by man-made and natural factors. In this article, we present a novel line-drawing enhanced interactive system for digital restoration of damaged murals in Mogao Grottoes. Our system consists of four components, namely data pre-processing, damaged area selection, line-drawing segmentation, and mural restoration. Each component is a hybrid of efficient algorithms and user interactions. We introduce the infrastructure and process of using our system, from data capture and collection, database establishment, to interactive restoration. We conduct a user study with 15 participants who have varied experiences with and skills on repairing murals and editing images. Results and feedback suggest that our system can achieve satisfactory restoration results without overburdening the users. It can benefit both experts trained in restoration and amateurs interested in cultural heritage conservation.

Empirical relationship between electrical resistivity and geotechnical parameters: A case study of Federal University of Technology campus, Akure SW, Nigeria

NASA Astrophysics Data System (ADS)

Akintorinwa, O. J.; Oluwole, S. T.

2018-06-01

For several decades, geophysical prospecting method coupled with geotechnical analysis has become increasingly useful in evaluating the subsurface for both pre and post engineering investigations. Shallow geophysical tool is often used alongside geotechnical method to evaluate subsurface soil for engineering study to obtain information which may include the subsurface lithology and their thicknesses, competence of the bedrock and depths to its upper interface, and competence of the material that make up the overburden, especially the shallow section which serves as host for foundations of engineering structures (Aina et al., 1996; Adewumi and Olorunfemi, 2005; and Idornigie et al., 2006). This information helps the engineers to correctly locate and design the foundation of engineering structures. The information also serves as guide to the choice of design and suitable materials needed for road construction (Akinlabi and Adeyemi, 2014). Lack of knowledge of the properties of subsurface may leads to the failure of most engineering structures. Therefore, it is of great importance to carry out a pre-construction investigation of a proposed site in order to ascertain the fitness of the host earth material.

Geologic and anthropogenic factors influencing karst development in the Frederick region of Maryland

USGS Publications Warehouse

Brezinski, D.K.

2007-01-01

Karst features pervade the outcrop belts of Triassic, Ordovician, and Cambrian rocks in the Frederick Valley region of Maryland's western Piedmont. Detailed stratigraphic analysis and geologic and karst mapping demonstrate that individual stratigraphic units have differing susceptibilities of karst feature creation. Although the Triassic Leesburg Member of the Bull Run Formation and Rocky Springs Station Member of the Cambrian Frederick Formation have many surface depressions within their outcrop belts, the Lime Kiln Member of the Frederick Formation and the Ceresville, Fountain Rock, and Woodsboro members of the Ordovician Grove Formation have the greatest potential for development of catastrophic collapse sinkholes. Although these four members have the highest relative susceptibility, human activity can increase the potential for sinkhole activation in all units. Rerouting of surface drainage patterns, unlined drainage, and storm-water management areas and removal of significant overburden deposits significantly increase sinkhole development, but mainly, these units are inherently more susceptible to begin with. Copyright ?? 2007. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

Glacial uplift: fluid injection beneath an elastic sheet on a poroelastic substrate

NASA Astrophysics Data System (ADS)

Neufeld, Jerome; Hewitt, Duncan; Chini, Greg

2016-11-01

Supraglacial lakes can drain to the base of glaciers extremely rapidly, causing localised uplift of the surrounding glacier and affecting its sliding velocity. The means by which large volumes of drained water interact with and leak into the subglacial hydrological system is unclear, as is the role of the basal till. A theoretical study of the spread of fluid injected below an elastic sheet (the ice) is presented, where the ice lies above, and initially compresses, a deformable poroelastic layer. As pressurized fluid is injected, the deformable layer swells to accommodate more fluid. If sufficient fluid is injected, a 'blister' of fluid forms above the layer, causing the overburden to lift off the base. The flow is controlled by the local pressure drop across the tip of this blister, which depends subtly on both the flow of fluid through the porous layer below the tip, and on poroelastic deformation in the till ahead of the tip. The spreading behaviour and dependence on key parameters is analysed. Predictions of the model are compared to field measurements of uplift from draining glacial lakes in Greenland.

Bauxite Mine Rehabilitation Programs — A Progress Report Patrick Atkins, Alcoa Inc.

NASA Astrophysics Data System (ADS)

Donaldson, Don; Raahauge, Benny E.

Bauxite is the primary source of raw material for the production of aluminum oxide and aluminum metal. At the current primary aluminum production level, known bauxite reserves will last for hundreds of years. Two to three tonnes of bauxite are required to produce one tonne of alumina and two tonnes of alumina are required to produce one tonne of aluminum metal. Typical bauxites contain from 30%-60% aluminum hydroxides and various levels of iron, silica, and titanium impurities. Approximately 125 million tonnes of bauxite are mined each year from 45 mines located on every continent except Antarctica. The major mining areas are located in the tropics, above and below the equator, as well as in Western Australia, the Caribbean Region, and the Mediterranean. Most bauxite is surface mined, although a few small underground mines remain active. The overburden depth ranges from almost none to several 10s of meters, with the average near five meters. The total land disturbed by bauxite mining each year is estimated to be 2,000-2,500 hectares per year.

CPT-based probabilistic and deterministic assessment of in situ seismic soil liquefaction potential

USGS Publications Warehouse

Moss, R.E.S.; Seed, R.B.; Kayen, R.E.; Stewart, J.P.; Der Kiureghian, A.; Cetin, K.O.

2006-01-01

This paper presents a complete methodology for both probabilistic and deterministic assessment of seismic soil liquefaction triggering potential based on the cone penetration test (CPT). A comprehensive worldwide set of CPT-based liquefaction field case histories were compiled and back analyzed, and the data then used to develop probabilistic triggering correlations. Issues investigated in this study include improved normalization of CPT resistance measurements for the influence of effective overburden stress, and adjustment to CPT tip resistance for the potential influence of "thin" liquefiable layers. The effects of soil type and soil character (i.e., "fines" adjustment) for the new correlations are based on a combination of CPT tip and sleeve resistance. To quantify probability for performancebased engineering applications, Bayesian "regression" methods were used, and the uncertainties of all variables comprising both the seismic demand and the liquefaction resistance were estimated and included in the analysis. The resulting correlations were developed using a Bayesian framework and are presented in both probabilistic and deterministic formats. The results are compared to previous probabilistic and deterministic correlations. ?? 2006 ASCE.

Thin seam miner/trench mining concepts for Illinois Basin surface coal mines

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

Caudle, R.D.; Lall, V.

1985-07-01

A hybrid surface/underground mining concept, trench-auger mining is an attempt to increase the depth to which coal seams can be surface mined economically by reducing the amount of overburden which must be removed and reclaimed. In this concept the coal seam is first exposed by digging a series of parallel trenches 400 to 1200 ft apart with conventional surface mining equipment. After surface mining the coal from the bottom of the trench, the coal under the surface between the trenches would be extracted with extended-depth augers, operating from the bottoms of the trenches. The RSV Mining Equipment Co. of Hollandmore » has developed a Thin Seam Miner (TSM). The TSM is essentially a remotely controlled, continuous underground mining machine. The hydraulically driven drum cutter head and coal handling auger flights can be operated from a distance outside the underground mine workings. The purpose of this study is to develop and evaluate Thin Seam Miner/Trench Mining (TSM/TM) concepts for use under conditions existing in the Illinois Coal Basin.« less

Standard penetration test-based probabilistic and deterministic assessment of seismic soil liquefaction potential

USGS Publications Warehouse

Cetin, K.O.; Seed, R.B.; Der Kiureghian, A.; Tokimatsu, K.; Harder, L.F.; Kayen, R.E.; Moss, R.E.S.

2004-01-01

This paper presents'new correlations for assessment of the likelihood of initiation (or triggering) of soil liquefaction. These new correlations eliminate several sources of bias intrinsic to previous, similar correlations, and provide greatly reduced overall uncertainty and variance. Key elements in the development of these new correlations are (1) accumulation of a significantly expanded database of field performance case histories; (2) use of improved knowledge and understanding of factors affecting interpretation of standard penetration test data; (3) incorporation of improved understanding of factors affecting site-specific earthquake ground motions (including directivity effects, site-specific response, etc.); (4) use of improved methods for assessment of in situ cyclic shear stress ratio; (5) screening of field data case histories on a quality/uncertainty basis; and (6) use of high-order probabilistic tools (Bayesian updating). The resulting relationships not only provide greatly reduced uncertainty, they also help to resolve a number of corollary issues that have long been difficult and controversial including: (1) magnitude-correlated duration weighting factors, (2) adjustments for fines content, and (3) corrections for overburden stress. ?? ASCE.

Determination of in situ state of stress at the Spent Fuel Test-Climax site, Climax Stock, Nevada Test Site

USGS Publications Warehouse

Ellis, W.L.; Magner, J.E.

1982-01-01

Determination of the in situ state of stress at the site of the Spent Fuel Test--Climax, using the U.S. Bureau of Mines overcore method, indicates principal stress magnitudes of 11.6 MPa, 7.1 MPa, and 2.8 MPa. The bearing and plunge of the maximum and minimum principal stress components are, respectively: N. 56? E., 29? NE; and N. 42? W., 14? NW. The vertical stress magnitude of 7.9 MPa calculated from the overcore data is significantly less than expected from overburden pressure, suggesting the stress field is influenced by local or areal geologic factors. Results from this investigation indicate (1) the stress state at the Spent Fuel Test--Climax site deviates significantly from a gravitational stress field, both in relative stress magnitudes and in orientation; (2) numerical modeling will not realistically simulate the near-field response of the Spent Fuel Test--Climax site if gravitational and (or) horizontal and vertical applied stress boundary conditions are assumed; and (3) substantial stress variations may occur spatially within the stock.

Status of EXO-200

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

Ackerman, Nicole; /SLAC

2011-12-06

EXO-200 is the first phase of the Enriched Xenon Observatory (EXO) experiment, which searches for neutrinoless double beta decay in {sup 136}Xe to measure the mass and probe the Majorana nature of the neutrino. EXO-200 consists of 200 kg of liquid Xe enriched to 80% in {sup 136}Xe in an ultra-low background TPC. Energy resolution is enhanced through the simultaneous collection of scintillation light using Large Area Avalanche Photodiodes (LAAPD's) and ionization charge. It is being installed at the WIPP site in New Mexico, which provides a 2000 meter water-equivalent overburden. EXO-200 will begin taking data in 2009, with themore » expected two-year sensitivity to the half-life for neutrinoless double beta decay of 6.4 x 10{sup 25} years. According to the most recent nuclear matrix element calculations, this corresponds to an effective Majorana neutrino mass of 0.13 to 0.19 eV. It will also measure the two neutrino mode for the first time in {sup 136}Xe.« less

SOME APPLICATIONS OF SEISMIC SOURCE MECHANISM STUDIES TO ASSESSING UNDERGROUND HAZARD.

USGS Publications Warehouse

McGarr, A.; ,

1984-01-01

Various measures of the seismic source mechanism of mine tremors, such as magnitude, moment, stress drop, apparent stress, and seismic efficiency, can be related directly to several aspects of the problem of determining the underground hazard arising from strong ground motion of large seismic events. First, the relation between the sum of seismic moments of tremors and the volume of stope closure caused by mining during a given period can be used in conjunction with magnitude-frequency statistics and an empirical relation between moment and magnitude to estimate the maximum possible sized tremor for a given mining situation. Second, it is shown that the 'energy release rate,' a commonly-used parameter for predicting underground seismic hazard, may be misleading in that the importance of overburden stress, or depth, is overstated. Third, results involving the relation between peak velocity and magnitude, magnitude-frequency statistics, and the maximum possible magnitude are applied to the problem of estimating the frequency at which design limits of certain underground support equipment are likely to be exceeded.

A search for double beta decays of 136Xe to the excited state of 136Ba with EXO-200

NASA Astrophysics Data System (ADS)

Yen, Yung-Ruey; EXO-200 Collaboration

2015-10-01

EXO-200 is one of the most sensitive searches for neutrinoless double beta decay of 136Xe in the world. The experiment uses 110 kg of active enriched liquid xenon in an ultralow background time projection chamber installed at the Waste Isolation Pilot Plant, a salt mine with a 1600 m water equivalent overburden. This detector has demonstrated excellent energy resolution and background rejection capabilities. While the experiment is designed to search for the double beta decays of 136Xe to the ground state of 136Ba, transitions to the excited states of 136Ba are also plausible. The ββ 2 ν decay to the first 0+ excited state of the daughter nuclei has been observed for 100Mo and 150Nd; this particular transition for 136Xe has a theoretical lifetime on the order of 1025 year, which is right around the sensitivity of EXO-200. We present the results from the search of double beta decays to the excited state using two years of EXO-200 data.

Documentation of a dissolved-solids model of the Tongue River, southeastern Montana

USGS Publications Warehouse

Woods, Paul F.

1981-01-01

A model has been developed for assessing potential increases in dissolved solids of the Tongue River as a result of leaching of overburden materials used to backfill pits in surface coal-mining operations. The model allows spatial and temporal simulation of streamflow and dissolved-solids loads and concentrations under user-defined scenarios of surface coal mining and agricultural development. The model routes an input quantity of streamflow and dissolved solids from the upstream end to the downstream end of a stream reach while algebraically accounting for gains and losses of streamflow and dissolved solids within the stream reach. Input data needed to operate the model include the following: simulation number, designation of hydrologic conditions for each simulated month, either user-defined or regression-defined concentrations of dissolved solids input by the Tongue River Reservoir, number of irrigated acres, number of mined acres, dissolved-solids concentration of mine leachates and quantity of other water losses. A listing of the Fortran computer program, definitions of all variables in the model, and an example output permit use of the model by interested persons. (USGS)

Acoustic response of cemented granular sedimentary rocks: molecular dynamics modeling.

PubMed

García, Xavier; Medina, Ernesto

2007-06-01

The effect of cementation processes on the acoustical properties of sands is studied via molecular dynamics simulation methods. We propose numerical methods where the initial uncemented sand is built by simulating the settling process of sediments. Uncemented samples of different porosity are considered by emulating natural mechanical compaction of sediments due to overburden. Cementation is considered through a particle-based model that captures the underlying physics behind the process. In our simulations, we consider samples with different degrees of compaction and cementing materials with distinct elastic properties. The microstructure of cemented sands is taken into account while adding cement at specific locations within the pores, such as grain-to-grain contacts. Results show that the acoustical properties of cemented sands are strongly dependent on the amount of cement, its stiffness relative to the hosting medium, and its location within the pores. Simulation results are in good correspondence with available experimental data and compare favorably with some theoretical predictions for the sound velocity within a range of cement saturation, porosity, and confining pressure.

Estimation of constitutive parameters for the Belridge Diatomite, South Belridge Diatomite Field

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

Fossum, A.F.; Fredrich, J.T.

1998-06-01

A cooperative national laboratory/industry research program was initiated in 1994 that improved understanding of the geomechanical processes causing well casing damage during oil production from weak, compactible formations. The program focused on the shallow diatomaceous oil reservoirs located in California`s San Joaquin Valley, and combined analyses of historical field data, experimental determination of rock mechanical behavior, and geomechanical simulation of the reservoir and overburden response to production and injection. Sandia National Laboratories` quasi-static, large-deformation structural mechanics finite element code JAS3D was used to perform the three-dimensional geomechanical simulations. One of the material models implemented in JAS3D to simulate the time-independentmore » inelastic (non-linear) deformation of geomaterials is a generalized version of the Sandler and Rubin cap plasticity model (Sandler and Rubin, 1979). This report documents the experimental rock mechanics data and material cap plasticity models that were derived to describe the Belridge Diatomite reservoir rock at the South Belridge Diatomite Field, Section 33.« less

Development of a low background liquid scintillation counter for a shallow underground laboratory

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

Erchinger, Jennifer L.; Aalseth, Craig E.; Bernacki, Bruce E.

2015-08-20

Pacific Northwest National Laboratory has recently opened a shallow underground laboratory intended for measurement of lowconcentration levels of radioactive isotopes in samples collected from the environment. The development of a low-background liquid scintillation counter is currently underway to further augment the measurement capabilities within this underground laboratory. Liquid scintillation counting is especially useful for measuring charged particle (e.g., B, a) emitting isotopes with no (orvery weak) gamma-ray yields. The combination of high-efficiency detection of charged particle emission in a liquid scintillation cocktail coupled with the low-background environment of an appropriately-designed shield located in a clean underground laboratory provides the opportunitymore » for increased-sensitivity measurements of a range of isotopes. To take advantage of the 35-meter water-equivalent overburden of the underground laboratory, a series of simulations have evaluated the instrumental shield design requirements to assess the possible background rate achievable. This report presents the design and background evaluation for a shallow underground, low background liquid scintillation counter design for sample measurements.« less

Estimating permeability from quasi-static deformation: Temporal variations and arrival time inversion

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

Vasco, D.W.; Ferretti, Alessandro; Novali, Fabrizio

2008-05-01

Transient pressure variations within a reservoir can be treated as a propagating front and analyzed using an asymptotic formulation. From this perspective one can define a pressure 'arrival time' and formulate solutions along trajectories, in the manner of ray theory. We combine this methodology and a technique for mapping overburden deformation into reservoir volume change as a means to estimate reservoir flow properties, such as permeability. Given the entire 'travel time' or phase field, obtained from the deformation data, we can construct the trajectories directly, there-by linearizing the inverse problem. A numerical study indicates that, using this approach, we canmore » infer large-scale variations in flow properties. In an application to Interferometric Synthetic Aperture (InSAR) observations associated with a CO{sub 2} injection at the Krechba field, Algeria, we image pressure propagation to the northwest. An inversion for flow properties indicates a linear trend of high permeability. The high permeability correlates with a northwest trending fault on the flank of the anticline which defines the field.« less

Geomechanical Considerations for the Deep Borehole Field Test

NASA Astrophysics Data System (ADS)

Park, B. Y.

2015-12-01

Deep borehole disposal of high-level radioactive waste is under consideration as a potential alternative to shallower mined repositories. The disposal concept consists of drilling a borehole into crystalline basement rocks to a depth of 5 km, emplacement of canisters containing solid waste in the lower 2 km, and plugging and sealing the upper 3 km of the borehole. Crystalline rocks such as granites are particularly attractive for borehole emplacement because of their low permeability and porosity at depth, and high mechanical strength to resist borehole deformation. In addition, high overburden pressures contribute to sealing of some of the fractures that provide transport pathways. We present geomechanical considerations during construction (e.g., borehole breakouts, disturbed rock zone development, and creep closure), relevant to both the smaller-diameter characterization borehole (8.5") and the larger-diameter field test borehole (17"). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

DAQ Software Contributions, Absolute Scale Energy Calibration and Background Evaluation for the NOvA Experiment at Fermilab

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

Flumerfelt, Eric Lewis

2015-08-01

The NOvA (NuMI Off-axis v e [nu_e] Appearance) Experiment is a long-baseline accelerator neutrino experiment currently in its second year of operations. NOvA uses the Neutrinos from the Main Injector (NuMI) beam at Fermilab, and there are two main off-axis detectors: a Near Detector at Fermilab and a Far Detector 810 km away at Ash River, MN. The work reported herein is in support of the NOvA Experiment, through contributions to the development of data acquisition software, providing an accurate, absolute-scale energy calibration for electromagnetic showers in NOvA detector elements, crucial to the primary electron neutrino search, and through anmore » initial evaluation of the cosmic background rate in the NOvA Far Detector, which is situated on the surface without significant overburden. Additional support work for the NOvA Experiment is also detailed, including DAQ Server Administration duties and a study of NOvA’s sensitivity to neutrino oscillations into a “sterile” state.« less

Natural mycorrhizal colonization of pines on reclaimed surface mines in Virginia. [Pinus strobus; Pinus taeda; Pinus virginiana

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

Schoenholtz, S.H.; Burger, J.A.; Torbert, J.L.

The effects of spoil type, slow-release fertilization, and weed control using glyphosate on the degree of ectomycorrhizal colonization of container-grown white (Pinus strobus L.), loblolly (P. taeda L.), and Virginia (P. virginiana Mill.) pines were studied on two strip mined sites (sandstone vs. siltstone overburden material) in southwestern Virginia. Although some seedlings were successfully colonized at both sites, the number of seedlings colonized and the proportion of short-root colonization per seedling were consistently higher on the sandstone spoil. On both sites, loblolly and Virginia pines had more ectomycorrhizal formation than white pine. Foliar P levels of all three species onmore » the sandstone spoil and of loblolly pine on the siltstone spoil were significantly correlated with ectomycorrhizal development. The degree of ectomycorrhizal formation for any of the species on either spoil was not decreased by slow-release fertilization or glyphosate applications. These results indicate that natural mycorrhizal colonization is compatible with these cultural treatments, and that colonization from indigenous fungal species may be adequate, eliminating the need for artificial inoculation.« less

Interpretation of Ground Temperature Anomalies in Hydrothermal Discharge Areas

NASA Astrophysics Data System (ADS)

Price, A. N.; Lindsey, C.; Fairley, J. P., Jr.

2017-12-01

Researchers have long noted the potential for shallow hydrothermal fluids to perturb near-surface temperatures. Several investigators have made qualitative or semi-quantitative use of elevated surface temperatures; for example, in snowfall calorimetry, or for tracing subsurface flow paths. However, little effort has been expended to develop a quantitative framework connecting surface temperature observations with conditions in the subsurface. Here, we examine an area of shallow subsurface flow at Burgdorf Hot Springs, in the Payette National Forest, north of McCall, Idaho USA. We present a simple analytical model that uses easily-measured surface data to infer the temperatures of laterally-migrating shallow hydrothermal fluids. The model is calibrated using shallow ground temperature measurements and overburden thickness estimates from seismic refraction studies. The model predicts conditions in the shallow subsurface, and suggests that the Biot number may place a more important control on the expression of near-surface thermal perturbations than previously thought. In addition, our model may have application in inferring difficult-to-measure parameters, such as shallow subsurface discharge from hydrothermal springs.

Identification Of Rippability And Bedrock Depth Using Seismic Refraction

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

Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M

2010-12-23

Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel.more » The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.« less

Methods and costs of thin-seam mining. Final report, 25 September 1977-24 January 1979. [Thin seam in association with a thick seam

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

Finch, T.E.; Fidler, E.L.

1981-02-01

This report defines the state of the art (circa 1978) in removing thin coal seams associated with vastly thicker seams found in the surface coal mines of the western United States. New techniques are evaluated and an innovative method and machine is proposed. Western states resource recovery regulations are addressed and representative mining operations are examined. Thin seam recovery is investigated through its effect on (1) overburden removal, (2) conventional seam extraction methods, and (3) innovative techniques. Equations and graphs are used to accommodate the variable stratigraphic positions in the mining sequence on which thin seams occur. Industrial concern andmore » agency regulations provided the impetus for this study of total resource recovery. The results are a compendium of thin seam removal methods and costs. The work explains how the mining industry recovers thin coal seams in western surface mines where extremely thick seams naturally hold the most attention. It explains what new developments imply and where to look for new improvements and their probable adaptability.« less

Evaluation of TBM tunnels with respect to stability against spalling

NASA Astrophysics Data System (ADS)

Shaalan, Heyam; Ismail, Mohd Ashraf Mohd; Azit, Romziah

2017-10-01

As the depth of tunnels and underground construction increases, instability occurs in the form of rock bursting or spalling because of the induced stresses. Spalling may appear as a strong compressive stress causing crack growth behind the excavated surface and buckling of the thin rock slabs. In this paper, we describe how to reduce the rock spalling failure to increase the underground safety and the tunnel stability. Thus, a parametric study is implemented using 2-D Elasto-plastic finite elements stress analysis software to investigate the parameters that can minimize the extent and depth of the failure zone. The critical section of Pahang Selangor Raw Water Transfer Tunnel under high overburden is analyzed. The effect of the shotcrete lining thickness, tunnel size and the removal of fallouts or scaled v-notch on the failure zone depth is investigated. The results demonstrate that the shotcrete lining thickness has less influence on the failure depth, while a small tunnel diameter minimizes the failure depth. In addition, the stability of the tunnel improves by removing the loose rock mass.

Bedside ABG, electrolytes, lactate and procalcitonin in emergency pediatrics

PubMed Central

Batra, Prerna; Dwivedi, Ajeet Kumar; Thakur, Neha

2014-01-01

Point of care testing, is the term commonly applied to the bedside tests performed in sick patients. Common clinical conditions encountered in pediatric emergency rooms are respiratory, gastro-intestinal, infections and cardiac. Emergencies at most of the places, especially developing countries are overburdened. Availability of tests like arterial blood gas, lactate, electrolytes and procalcitonin, bedside tests or point of care tests can help identify sick patients quickly. Abnormalities like acid-base disturbances and dyselectrolytemias can be dealt with instantly, thus improving the overall prognosis. Lactate levels in emergency give the earliest clue to cardiovascular compromise and poor tissue perfusion. Procalcitonin has recently gained significant importance as an acute phase reactant for early identification of sepsis. Decisions for initiating or withholding antibiotic therapy can also be taken based on procalcitonin levels in emergency. Bedside estimation of serum electrolytes, blood gas analysis and procalcitonin thus facilitate the clinical evaluation and management of critical patients. An extensive literature review of current status of these investigations as point of care tests is appraised here. PMID:25337488

Cell Wall Remodeling by a Synthetic Analog Reveals Metabolic Adaptation in Vancomycin Resistant Enterococci.

PubMed

Pidgeon, Sean E; Pires, Marcos M

2017-07-21

Drug-resistant bacterial infections threaten to overburden our healthcare system and disrupt modern medicine. A large class of potent antibiotics, including vancomycin, operate by interfering with bacterial cell wall biosynthesis. Vancomycin-resistant enterococci (VRE) evade the blockage of cell wall biosynthesis by altering cell wall precursors, rendering them drug insensitive. Herein, we reveal the phenotypic plasticity and cell wall remodeling of VRE in response to vancomycin in live bacterial cells via a metabolic probe. A synthetic cell wall analog was designed and constructed to monitor cell wall structural alterations. Our results demonstrate that the biosynthetic pathway for vancomycin-resistant precursors can be hijacked by synthetic analogs to track the kinetics of phenotype induction. In addition, we leveraged this probe to interrogate the response of VRE cells to vancomycin analogs and a series of cell wall-targeted antibiotics. Finally, we describe a proof-of-principle strategy to visually inspect drug resistance induction. Based on our findings, we anticipate that our metabolic probe will play an important role in further elucidating the interplay among the enzymes involved in the VRE biosynthetic rewiring.

Log analysis of six boreholes in conjunction with geologic characterization above and on top of the Weeks Island Salt Dome

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

Sattler, A.R.

1996-06-01

Six boreholes were drilled during the geologic characterization and diagnostics of the Weeks Island sinkhole that is over the two-tiered salt mine which was converted for oil storage by the U.S. Strategic Petroleum Reserve. These holes were drilled to provide for geologic characterization of the Weeks Island Salt Dome and its overburden in the immediate vicinity of the sinkhole (mainly through logs and core); to establish a crosswell configuration for seismic tomography; to establish locations for hydrocarbon detection and tracer injection; and to provide direct observations of sinkhole geometry and material properties. Specific objectives of the logging program were to:more » (1) identify the top of and the physical state of the salt dome; (2) identify the water table; (3) obtain a relative salinity profile in the aquifer within the alluvium, which ranges from the water table directly to the top of the Weeks Island salt dome; and (4) identify a reflecting horizon seen on seismic profiles over this salt dome. Natural gamma, neutron, density, sonic, resistivity and caliper logs were run.« less

Search for Ultra-High-Energy Neutrinos with AMANDA-II

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

Ackermann, M.; Bernardini, E.; Adams, J.

2008-03-10

A search for diffuse neutrinos with energies in excess of 10{sup 5} GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10{sup 7} GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra-high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrinomore » flux of E{sup 2}{phi}{sub 90%CL} < 2.7 x 10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1} valid over the energy range of 2 x 10{sup 5} to 10{sup 9} GeV. A number of models that predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.« less

Search for Ultra High-Energy Neutrinos with AMANDA-II

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

IceCube Collaboration; Klein, Spencer; Ackermann, M.

2007-11-19

A search for diffuse neutrinos with energies in excess of 10{sup 5} GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10{sup 7} GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavormore » neutrino flux of E{sup 2} {Phi}{sub 90%CL} < 2.7 x 10{sup -7} GeV cm{sup -2}s{sup -1} sr{sup -1} valid over the energy range of 2 x 10{sup 5} GeV to 10{sup 9} GeV. A number of models which predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.« less

Gravel seeding - A suitable technique for restoring the seabed following marine aggregate dredging?

NASA Astrophysics Data System (ADS)

Cooper, Keith; Ware, Suzanne; Vanstaen, Koen; Barry, Jon

2011-01-01

Restoration of offshore marine habitats is a relatively new concept, with attempts in the European Union being largely instigated by requirements of various strategic directives. In this experiment, we investigate the practicality and effectiveness of gravel seeding, using a commercial aggregate dredging vessel, in order to recreate a gravel habitat. The experimental design consisted of a Treatment and Control site, both within an area of historic dredging characterised by an overburden of sand, and a gravel dominated Reference site. All sites were surveyed, using a combination of acoustic, camera and grab techniques, 2 months before, and then at 0, 12 and 22 months after the deposition of 4444 m 3 of gravel dominated sediments within the Treatment site. Although financial and practical constraints limited replication of the Treatment to one area, and so precluded strong statistical conclusions, our results suggested that the technique was both practically feasible, and successful in terms of returning the physical and biological attributes at the Treatment site to a state more representative of gravelly substrata in the wider, un-impacted environment.

Promoting Healthy Outcomes Among Youth with Multiple Risks: Innovative Approaches

PubMed Central

Greenberg, Mark T.; Lippold, Melissa A.

2015-01-01

Adolescent behavior problems such as substance use, antisocial behavior problems, and mental health problems have extremely high social costs and lead to overburdened mental health and juvenile justice systems in the United States and Europe. The prevalence of these problems is substantial, and at-risk youth often present with a combination of concerns. An understanding of risk and protective factors at multiple levels, including the child, family, peer, school, and community, has influenced intervention development. At the individual and family levels, the most effective and cost-effective programs work intensively with youth and their families or use individual and group cognitive-behavioral approaches. However, there is a paucity of careful studies of effective policies and programs in the juvenile justice system. Research is needed that focuses on adoption, financing, implementation, and sustainable use of evidence-based programs in public service systems. In addition, the field needs to understand better for whom current programs are most effective to create the next generation of more effective and efficient programs. PMID:23297659

Rapid trench initiated recrystallization and stagnation in narrow Cu interconnect lines

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

O'Brien, Brendan B.; Rizzolo, Michael; Prestowitz, Luke C.

2015-10-26

Understanding and ultimately controlling the self-annealing of Cu in narrow interconnect lines has remained a top priority in order to continue down-scaling of back-end of the line interconnects. Recently, it was hypothesized that a bottom-up microstructural transformation process in narrow interconnect features competes with the surface-initiated overburden transformation. Here, a set of transmission electron microscopy images which captures the grain coarsening process in 48 nm lines in a time resolved manner is presented, supporting such a process. Grain size measurements taken from these images have demonstrated that the Cu microstructural transformation in 48 nm interconnect lines stagnates after only 1.5 h atmore » room temperature. This stubborn metastable structure remains stagnant, even after aggressive elevated temperature anneals, suggesting that a limited internal energy source such as dislocation content is driving the transformation. As indicated by the extremely low defect density found in 48 nm trenches, a rapid recrystallization process driven by annihilation of defects in the trenches appears to give way to a metastable microstructure in the trenches.« less

Volume Based Curvature Attributes Illuminate Stress Effects in Contiguous Fault Blocks, Central Basin Platform, West Texas

NASA Astrophysics Data System (ADS)

Blumentritt, C. H.; Marfurt, K. J.

2005-05-01

We compute curvatures for 3-D seismic volumes covering 200+ mi2 of the Central Basin Platform in West Texas and find that these attributes illumination lineations not seen on other displays of the seismic data. We analyze the preferred orientations of these lineations defined by well imaged faults and fault zones and find that the patterns vary according to the nature of the faults bounding the blocks, mostly strike-slip, high angle reverse, or oblique slip. We perform the analysis in the pre-Mississippian section which is decoupled from the overburden by a Permian age unconformity. Our technique differs from that of previous workers in that we compute curvatures on each sample of a seismic volume using a moving subvolume rather than along surfaces interpreted from the data. In this way, we minimize high frequency variations in the results that arise from picking errors in the interpretation or noise in the data. We are able to extract and display values of curvature along time or depth slices, along horizon slices, and along poorly imaged horizons.

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

Ben-Avraham, Z.; Nur, A.

The elevation above sea level of circum-Pacific volcanoes situated on continental crust varies greatly, not only between various chains but also within chains. Their edifice heights, however, are essentially constant with each chain. This pattern is reversed for oceanic volcanoes: The elevation circum-Pacific volcanoes situated on oceanic curst is constant within arcs, while edifice heights are greatly variable. In continents the depth to the root zones of volcanoes may be within the elastic part of the lithosphere, whereas in the oceans it may be well below the elastic part of the lithosphere. We suggest that melting, or the onset ofmore » the volcanic uprising, may be controlled in both cases primarily by pressure: in the continental lithosphere by the overburden pressure determined by depth below the local surface and in the oceanic lithosphere by the isostatically compensated pressure zone controlled by depth below sea level. The pattern seems to hold even in complex geological regions and may be used to identify the nature of the crust in such regions.« less

Hydrology of the Ferron sandstone aquifer and effects of proposed surface-coal mining in Castle Valley, Utah, with sections on stratigraphy and leaching of overburden

USGS Publications Warehouse

Lines, Gregory C.; Morrissey, Daniel J.; Ryer, Thomas A.; Fuller, Richard H.

1983-01-01

Coal in the Ferron Sandstone Member of the Mancos Shale of Cretaceous age has traditionally been mined by underground techniques in the Emery Coal Field in the southern end of Castle Valley in east-central Utah. However, approximately 99 million tons are recoverable by surface mining. Ground water in the Ferron is the sole source of supply for the town of Emery, but the aquifer is essentially untapped outside the Emery area.The Ferron Sandstone Member crops out along the eastern edge of Castle Valley and generally dips 2 ? to 10 ? to the northwest. Sandstones in the Ferron are enclosed between relatively impermeable shale in the Tununk and Blue Gate Members of the Mancos Shale. Along the outcrop, the Ferron ranges in thickness from about 80 feet in the northern part of Castle Valley to 850 feet in the southern part. The Ferron also generally thickens in the subsurface downdip from the outcrop. Records from wells and test holes indicate that the full thickness of the Ferron is saturated with water in most areas downdip from the outcrop area.Tests in the Emery area indicate that transmissivity of the Ferron sandstone aquifer ranges from about 200 to 700 feet squared per day where the Ferron is fully saturated. Aquifer transmissivity is greatest near the Paradise Valley-Joes Valley fault system where permeability has been increased by fracturing. Storage coefficient ranges from about 10 .6 to 10 -3 where the Ferron sandstone aquifer is confined and probably averages 5 x 10-2 where it is unconfined.

Accurate relative location estimates for the North Korean nuclear tests using empirical slowness corrections

NASA Astrophysics Data System (ADS)

Gibbons, S. J.; Pabian, F.; Näsholm, S. P.; Kværna, T.; Mykkeltveit, S.

2017-01-01

velocity gradients reduce the residuals, the relative location uncertainties and the sensitivity to the combination of stations used. The traveltime gradients appear to be overestimated for the regional phases, and teleseismic relative location estimates are likely to be more accurate despite an apparent lower precision. Calibrations for regional phases are essential given that smaller magnitude events are likely not to be recorded teleseismically. We discuss the implications for the absolute event locations. Placing the 2006 event under a local maximum of overburden at 41.293°N, 129.105°E would imply a location of 41.299°N, 129.075°E for the January 2016 event, providing almost optimal overburden for the later four events.

A Markov Chain Monte Carlo Inversion Approach For Inverting InSAR Data With Application To Subsurface CO2 Injection

NASA Astrophysics Data System (ADS)

Ramirez, A. L.; Foxall, W.

2011-12-01

Surface displacements caused by reservoir pressure perturbations resulting from CO2 injection can often be measured by geodetic methods such as InSAR, tilt and GPS. We have developed a Markov Chain Monte Carlo (MCMC) approach to invert surface displacements measured by InSAR to map the pressure distribution associated with CO2 injection at the In Salah Krechba field, Algeria. The MCMC inversion entails sampling the solution space by proposing a series of trial 3D pressure-plume models. In the case of In Salah, the range of allowable models is constrained by prior information provided by well and geophysical data for the reservoir and possible fluid pathways in the overburden, and injection pressures and volumes. Each trial pressure distribution source is run through a (mathematical) forward model to calculate a set of synthetic surface deformation data. The likelihood that a particular proposal represents the true source is determined from the fit of the calculated data to the InSAR measurements, and those having higher likelihoods are passed to the posterior distribution. This procedure is repeated over typically ~104 - 105 trials until the posterior distribution converges to a stable solution. The solution to each stochastic inversion is in the form of Bayesian posterior probability density function (pdf) over the range of the alternative models that are consistent with the measured data and prior information. Therefore, the solution provides not only the highest likelihood model but also a realistic estimate of the solution uncertainty. Our InSalah work considered three flow model alternatives: 1) The first model assumed that the CO2 saturation and fluid pressure changes were confined to the reservoir; 2) the second model allowed the perturbations to occur also in a damage zone inferred in the lower caprock from 3D seismic surveys; and 3) the third model allowed fluid pressure changes anywhere within the reservoir and overburden. Alternative (2) yielded optimal

New strategies to increase the restoration success of post-mining landscapes: the application of cyanobacteria to seed-based rehabilitation programs

NASA Astrophysics Data System (ADS)

Muñoz-Rojas, Miriam; Raúl Román Fernández, José; Roncero Ramos, Beatriz; Cantón Castilla, Yolanda

2017-04-01

Despite the large efforts and investments to dryland ecosystems restoration worldwide, land rehabilitation in these areas has very low rates of success. Most of the challenges in landscape-scale restoration come from the lack of suitable soil substrates to support plant establishment and to ultimately achieve functional ecosystems. A common practice during extractive operations such as open-cut and strip mining is the removal of the topsoil layer that is subsequently stockpiled and respread in areas targeted for restoration. This topsoil is a crucial source of seeds, nutrients, and microorganisms but is a scarce resource which challenges the success of many restoration programs. In these conditions, the use of direct seeding of key native plant species becomes critical to reinstate biodiverse vegetation communities. Alternative soil substrates such as overburden or waste materials produced in mining operations are increasingly being used as growth media in restoration. However, these soil substrates can have inadequate levels of pH or salinity for plant growth and in most cases are depleted in organic materials and nutrients. In these conditions, the establishment of native plant species can be extremely difficult with a consequent potential loss of biodiversity. Development of appropriate soil structures such as technosols can be extremely expensive and demanding in terms of time and natural resources soils and therefore new approached need to be explored. In the last years, the potential of cyanobacteria biological crust to restore soil functionality in degraded has been highlighted because of their important role in controlling soil structure, preventing soil erosion and N and C fixation. Nevertheless, many research gaps still remain in their application to restore soil functionality in seed-based restoration practices. In this study, we test the potential of cyanobacteria inoculation to restore soil functions of soil materials used in post-mine restoration

Stress Changes and Deformation Monitoring of Longwall Coal Pillars Located in Weak Ground

NASA Astrophysics Data System (ADS)

Yu, Bin; Zhang, Zhenyu; Kuang, Tiejun; Liu, Jinrong

2016-08-01

Coal pillar stability is strongly influenced by the site-specific geological and geotechnical conditions. Many geological structures such as faults, joints, or rock intrusions can be detrimental to mining operations. In order to evaluate the performance of coal pillars under weak roof degraded by igneous rock intrusion, stress and deformation monitoring was conducted in the affected tailgate areas of Nos. 8208 and 8210 longwalls in Tashan coal mine, Shanxi Province, China. The measurements in the 8208 longwall tailgate showed that the mining-induced stresses in 38-m-wide coal chain pillars under the overburden depth of 300-500 m started to increase at about 100 m ahead of the 8208 longwall working face and reached its peak level at approximately 50 m ahead of the longwall face. The peak stress of 9.16 MPa occurred at the depth of 8-9 m into the pillar from the tailgate side wall. In comparison, disturbance of the headgate block pillar area was negligible, indicating the difference of abutment pressure distribution between the tailgate and headgate sites where the adjacent unmined longwall block carried most of the overburden load. However, when the longwall face passed the headgate monitoring site by 360-379 m, the pillar stress increased to a peak value of 21.4 MPa at the pillar depth of 13 m from the gob side mainly due to stress redistribution in the chain pillar. In contrast to the headgate, at the tailgate side, the adjacent goaf was the dominant triggering factor for high stress concentrations in the chain pillar. Convergence measurements in the tailgate during longwall mining further indicated the evolution characteristics of coal pillar deformation, clearly showing that the gateroad deformation is mainly induced by the longwall extraction it serves. When predicting the future pillar loads from the monitored data, two stress peaks appeared across the 38-m-wide tailgate coal pillar, which are separated by the lower stress area within the pillar center. This

Fault analysis as part of urban geothermal exploration in the German Molasse Basin around Munich

NASA Astrophysics Data System (ADS)

Ziesch, Jennifer; Tanner, David C.; Hanstein, Sabine; Buness, Hermann; Krawczyk, Charlotte M.; Thomas, Rüdiger

2017-04-01

Faults play an essential role in geothermal exploration. The prediction of potential fluid pathways in urban Munich has been started with the interpretation of a 3-D seismic survey (170 km2) that was acquired during the winter of 2015/2016 in Munich (Germany) within the Bavarian Molasse Basin. As a part of the research project GeoParaMoL*, we focus on the structural interpretation and retro-deformation analysis to detect sub-seismic structures within the reservoir and overburden. We explore the hydrothermal Malm carbonate reservoir (at a depth of 3 km) as a source of deep geothermal energy and the overburden of Tertiary Molasse sediments. The stratigraphic horizons, Top Aquitan, Top Chatt, Top Bausteinschichten, Top Lithothamnien limestone (Top Eocene), Top and Base Malm (Upper Jurassic), together with the detailed interpretation of the faults in the study area are used to construct a 3-D geological model. The study area is characterised by synthetic normal faults that strike parallel to the alpine front. Most major faults were active from Upper Jurassic up to the Miocene. The Munich Fault, which belongs to the Markt-Schwabener Lineament, has a maximum vertical offset of 350 metres in the central part, and contrary to previous interpretation based on 2-D seismic, this fault dies out in the eastern part of the area. The south-eastern part of the study area is dominated by a very complex fault system. Three faults that were previously detected in a smaller 3-D seismic survey at Unterhaching, to the south of the study area, with strike directions of 25°, 45° and 70° (Lüschen et al. 2014), were followed in to the new 3-D seismic survey interpretation. Particularly noticeable are relay ramps and horst/graben structures. The fault with a strike of 25° ends in three big sinkholes with a maximum vertical offset of 60 metres. We interpret this special structure as fault tip horsetail-structure, which caused a large amount of sub-seismic deformation. Consequently, this

Autonomous mine detection system (AMDS) neutralization payload module

NASA Astrophysics Data System (ADS)

Majerus, M.; Vanaman, R.; Wright, N.

2010-04-01

The Autonomous Mine Detection System (AMDS) program is developing a landmine and explosive hazards standoff detection, marking, and neutralization system for dismounted soldiers. The AMDS Capabilities Development Document (CDD) has identified the requirement to deploy three payload modules for small robotic platforms: mine detection and marking, explosives detection and marking, and neutralization. This paper addresses the neutralization payload module. There are a number of challenges that must be overcome for the neutralization payload module to be successfully integrated into AMDS. The neutralizer must meet stringent size, weight, and power (SWaP) requirements to be compatible with a small robot. The neutralizer must be effective against a broad threat, to include metal and plastic-cased Anti-Personnel (AP) and Anti-Tank (AT) landmines, explosive devices, and Unexploded Explosive Ordnance (UXO.) It must adapt to a variety of threat concealments, overburdens, and emplacement methods, to include soil, gravel, asphalt, and concrete. A unique neutralization technology is being investigated for adaptation to the AMDS Neutralization Module. This paper will describe review this technology and how the other two payload modules influence its design for minimizing SWaP. Recent modeling and experimental efforts will be included.

Conditions and development case studies for mountainous deposits in Siberia

NASA Astrophysics Data System (ADS)

Talgamer, B. L.; Franchuk, A. V.

2017-10-01

The article contains the materials on deposits development intensification under challenging climatic and mining conditions, including mountainous areas of Siberia. The exploitation case studies for mountainous deposits all over the world and in Russia have been described. The authors have been set out the factors impeding the development of such deposits, and the extent of mining and transportation equipment performance degradation is also indicated. There have been stated the characteristics and the description of one of the newly mountainous gold ore deposits in Siberia which is being developed at an altitude of 2684m. A number of specific factors concerning its development have also been introduced as well as the description of mining technologies engineered by Irkutsk National Research Technical University (IRNRTU) specialists. The depth and principal dimensions of the open pit together with the mining and transportation equipment and facilities have been justified. The prime cost analysis of mineral extraction has been made, which results showed the substantial growth in expenditures for the transportation of the overburden rocks and ores. In view of the above mentioned research, there appeared the necessity for the search of new and the enhancement of current transport vehicles and communications.

Impacts of gold mine waste disposal on deepwater fish in a pristine tropical marine system.

PubMed

Brewer, D T; Milton, D A; Fry, G C; Dennis, D M; Heales, D S; Venables, W N

2007-03-01

Little is known about the impacts of mine waste disposal, including deep-sea tailings, on tropical marine environments and this study presents the first account of this impact on deepwater fish communities. The Lihir gold mine in Papua New Guinea has deposited both excavated overburden and processed tailings slurry into the coastal environment since 1997. The abundances of fish species and trace metal concentrations in their tissues were compared between sites adjacent to and away from the mine. In this study (1999-2002), 975 fish of 98 species were caught. Significantly fewer fish were caught close to the mine than in neighbouring regions; the highest numbers were in regions distant from the mine. The catch rates of nine of the 17 most abundant species were lowest, and in three species were highest, close to the mine. There appears to be limited contamination in fish tissues caused by trace metals disposed as mine waste. Although arsenic (several species) and mercury (one species) were found in concentrations above Australian food standards. However, as in the baseline (pre-mine) sampling, it appears they are accumulating these metals mostly from naturally-occurring sources rather than the mine waste.