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Sample records for heterogeneous geological formations

  1. Intermediate Scale Laboratory Testing to Understand Mechanisms of Capillary and Dissolution Trapping during Injection and Post-Injection of CO2 in Heterogeneous Geological Formations

    SciTech Connect

    Illangasekare, Tissa; Trevisan, Luca; Agartan, Elif; Mori, Hiroko; Vargas-Johnson, Javier; González-Nicolás, Ana; Cihan, Abdullah; Birkholzer, Jens; Zhou, Quanlin

    2015-03-31

    Carbon Capture and Storage (CCS) represents a technology aimed to reduce atmospheric loading of CO2 from power plants and heavy industries by injecting it into deep geological formations, such as saline aquifers. A number of trapping mechanisms contribute to effective and secure storage of the injected CO2 in supercritical fluid phase (scCO2) in the formation over the long term. The primary trapping mechanisms are structural, residual, dissolution and mineralization. Knowledge gaps exist on how the heterogeneity of the formation manifested at all scales from the pore to the site scales affects trapping and parameterization of contributing mechanisms in models. An experimental and modeling study was conducted to fill these knowledge gaps. Experimental investigation of fundamental processes and mechanisms in field settings is not possible as it is not feasible to fully characterize the geologic heterogeneity at all relevant scales and gathering data on migration, trapping and dissolution of scCO2. Laboratory experiments using scCO2 under ambient conditions are also not feasible as it is technically challenging and cost prohibitive to develop large, two- or three-dimensional test systems with controlled high pressures to keep the scCO2 as a liquid. Hence, an innovative approach that used surrogate fluids in place of scCO2 and formation brine in multi-scale, synthetic aquifers test systems ranging in scales from centimeter to meter scale developed used. New modeling algorithms were developed to capture the processes controlled by the formation heterogeneity, and they were tested using the data from the laboratory test systems. The results and findings are expected to contribute toward better conceptual models, future improvements to DOE numerical codes, more accurate assessment of storage capacities, and optimized placement strategies. This report presents the experimental and modeling methods and research results.

  2. Exchange flow with geological heterogeneity

    NASA Astrophysics Data System (ADS)

    Chang, K.; Hesse, M. A.

    2013-12-01

    Two aquifers can be hydraulically connected by a fault cutting across the intermediate aquitard. If the upper aquifer contains denser fluid, an exchange flow across the fault will develop. The unstable density stratification leads to fingering pattern with localized zones of upwelling and downwelling along the fault. Due to the small volume of the fault relative to the aquifers the exchange-flow will quickly approach a quasi steady state. If the permeability of the fault plane is homogeneous, the average number of the quasi-steady plume fingers, , follows a power law function of the Rayleigh number Ra (? Ra1/2) and the exchange rate measured by dimensionless convective flux, the Sherwood number Sh, is a linear function of Ra (Sh? Ra). The presence of flow barriers along the fault triggers unsteady exchange flow and subsequently controls the growth of the plume fingers. If the barriers are sufficiently wide to dominate the flow system, they creates preferential pathways for exchange flow that determines the distribution of the quasi-steady fingers, and converges to a constant value. In addition, wider barriers induce substantial lateral spreading and enhance the efficiency of structural trapping, and reduce the exchange rate that follows a power law Sh? Ran, where n<1 and decreases with increasing barrier length. This study is motivated by geological carbon dioxide (CO2) storage in brine-saturated aquifer, but the unstable exchange of multiphase fluids through conductive faults is also important in many other geological and engineering applications, in particular the migration of hydrocarbons in tectonic-driven faulting system or hydraulically developed fractures in unconventional reservoirs. Better understanding of the density-driven flow in a faulted system will allow more precise estimate of the reservoir capacity as well as more efficient operation of injection or production wells.

  3. Formation evaluation: Geological procedures

    SciTech Connect

    Whittaker, A.

    1985-01-01

    This volume goes beyond a discussion of petroleum geology and the techniques of hydrocarbon (oil and gas) logging as a reservoir evaluation tool. It provides the logging geologist with a review of geological techniques and classification systems that will ensure the maximum development of communicable geological information. Contents include: 1. Introduction--cuttings recovery, cutting sampling, core sampling, rock classification; 2. Detrital rocks--classification, description; 3. Carbonate rocks--classification, description; 4. Chemical rocks-introduction, siliceous rocks, ferruginous rocks, aluminous rocks, phosphatic rocks, aluminous rocks, carbonaceous rocks; 5. Igneous and metamorpbic rocks; Appendix; References and Index.

  4. Heterogeneity and Scaling in Geologic Media

    SciTech Connect

    Gregory N. Boitnott; Gilles Y. Bussod; Paul N. Hagin; Stephen R. Brown

    2005-04-18

    The accurate characterization and remediation of contaminated subsurface environments requires the detailed knowledge of subsurface structures and flow paths. Enormous resources are invested in scoping and characterizing sites using core sampling, 3-D geophysical surveys, well tests, etc.... Unfortunately, much of the information acquired is lost to compromises and simplifications made in constructing numerical grids for the simulators used to predict flow and transport from the contaminated area to the accessible environment. In rocks and soils, the bulk geophysical and transport properties of the matrix and of fracture systems are determined by the juxtaposition of geometric features at many length scales. In the interest of computational efficiency, recognized heterogeneities are simplified, averaged out, or entirely ignored in spite of recent studies that recognize that: (1) Structural and lithologic heterogeneities exist on all scales in rocks. (2) Small heterogeneities influence, and can control the physical and chemical properties of rocks. In this work we propose a physically based approach for the description and treatment of heterogeneities, that highlights the use of laboratory equipment designed to measure the effect on physical properties of fine scale heterogeneities observed in rocks and soils. We then discuss the development of an integration methodology that uses these measurements to develop and upscale flow and transport models. Predictive simulations are 'calibrated' to the measured heterogeneity data, and subsequently upscaled in a way that is consistent with the transport physics and the efficient use of environmental geophysics. This methodology provides a more accurate interpretation and representation of the subsurface for both environmental engineering and remediation. We show through examples, (i) the important influence of even subtle heterogeneity in the interpreting of geophysical data, and (ii) how physically based upscaling can lead to a different and more accurate description of a heterogeneous system, when compared to a more traditional upscaling approach that combines averaging and the application of core-based models. This may be of particular significance in bio-remediation studies where the link between microorganism activity and mesoscale flow through geologic structures, resides in the integration of multiscale processes.

  5. Method of fracturing a geological formation

    DOEpatents

    Johnson, James O. (2679-B Walnut, Los Alamos, NM 87544)

    1990-01-01

    An improved method of fracturing a geological formation surrounding a well bore is disclosed. A relatively small explosive charge is emplaced in a well bore and the bore is subsequently hydraulically pressurized to a pressure less than the formation breakdown pressure and preferably greater than the fracture propagation pressure of the formation. The charge is denoted while the bore is so pressurized, resulting in the formation of multiple fractures in the surrounding formation with little or no accompanying formation damage. Subsequent hydraulic pressurization can be used to propagate and extend the fractures in a conventional manner. The method is useful for stimulating production of oil, gas and possibly water from suitable geologic formations.

  6. Experimental study on effects of geologic heterogeneity in enhancing dissolution trapping of supercritical CO2

    NASA Astrophysics Data System (ADS)

    Agartan, Elif; Trevisan, Luca; Cihan, Abdullah; Birkholzer, Jens; Zhou, Quanlin; Illangasekare, Tissa H.

    2015-03-01

    Dissolution trapping is one of the primary mechanisms that enhance the storage security of supercritical carbon dioxide (scCO2) in saline geologic formations. When scCO2 dissolves in formation brine produces an aqueous solution that is denser than formation brine, which leads to convective mixing driven by gravitational instabilities. Convective mixing can enhance the dissolution of CO2 and thus it can contribute to stable trapping of dissolved CO2. However, in the presence of geologic heterogeneities, diffusive mixing may also contribute to dissolution trapping. The effects of heterogeneity on mixing and its contribution to stable trapping are not well understood. The goal of this experimental study is to investigate the effects of geologic heterogeneity on mixing and stable trapping of dissolved CO2. Homogeneous and heterogeneous media experiments were conducted in a two-dimensional test tank with various packing configurations using surrogates for scCO2 (water) and brine (propylene glycol) under ambient pressure and temperature conditions. The results show that the density-driven flow in heterogeneous formations may not always cause significant convective mixing especially in layered systems containing low-permeability zones. In homogeneous formations, density-driven fingering enhances both storage in the deeper parts of the formation and contact between the host rock and dissolved CO2 for the potential mineralization. On the other hand, for layered systems, dissolved CO2 becomes immobilized in low-permeability zones with low-diffusion rates, which reduces the risk of leakage through any fault or fracture. Both cases contribute to the permanence of the dissolved plume in the formation.

  7. Secondary Organic Aerosol Formation by Heterogeneous

    E-print Network

    Goddard III, William A.

    are in qualitatively agreement with previous studies. In addition, the QM results for glyoxal reactions are consistentSecondary Organic Aerosol Formation by Heterogeneous Reactions of Aldehydes and Ketones: A Quantum chemical reactions (possibly acid-catalyzed) are involved to some extent in theformationof

  8. A Fundamental Study of Convective Mixing of CO2 in Heterogeneous Geologic Media using Surrogate Fluids and Numerical Modeling

    E-print Network

    to investigate how the geologic architecture that defines the spatial distribution of low permeability zones control volume balance does not limit cell shape and provides mass, momentum, energy conservation permeability and scaling effects on convective mixing in heterogeneous formations. References - Backhaus, S

  9. Simulation of Seismic Tunnel Detection Experiments in Heterogeneous Geological Media

    NASA Astrophysics Data System (ADS)

    Sherman, C. S.; Glaser, S. D.; Rector, J.

    2013-12-01

    Detecting covert tunnels and other underground openings is an important yet challenging problem for geophysicists, especially where geological heterogeneity is pronounced. A number of geophysical methods have been employed to solve this problem, each with varying degrees of success. We focus on the near-surface seismic techniques of surface wave backscattering, surface wave attenuation tomography, body wave diffraction imaging, and resonant imaging. We use the elastodynamic wave propagation code E3D to simulate tunnel detection experiments completed at this site for a range of synthetic fractal velocity models. The Black Diamond mine, located near Pittsburg California, is used for the field test of our analysis. Our results show that for the relatively low-frequency surface wave attenuation and backscattering methods, the maximum detectable tunnel depth in a homogenous medium is approximately equal to the wavelength of the probing Rayleigh wave. The higher-frequency body wave diffraction and resonant imaging techniques are able to locate tunnels at greater depths, but require more sophisticated analysis and are prone to greater attenuation losses. As is expected, for large values of heterogeneity amplitude, ?, the percent standard deviation from the mean velocity model, the average observed surface wave attenuation signal decreases and the maximum detectable tunnel depth decreases. However, for moderate values of heterogeneity amplitude (? < 3%), the average surface wave attenuation signal increases and the maximum detectable tunnel depth increases. For the body wave diffraction and resonant imaging experiments, as ? increases the complexity of the observed signal increases, resulting in more difficult processing and interpretation. The additional scattering attenuation tends to degrade the signals significantly due to their reliance on lower amplitude and higher frequency waves.

  10. Geologic Study of the Coso Formation

    SciTech Connect

    D. L. Kamola; J. D. Walker

    1999-12-01

    There have been great advances in the last 20 years in understanding the volcanic, structural, geophysical, and petrologic development of the Coso Range and Coso geothermal field. These studies have provided a wealth of knowledge concerning the geology of the area, including general structural characteristics and kinematic history. One element missing from this dataset was an understanding of the sedimentology and stratigraphy of well-exposed Cenozoic sedimentary strata - the Coso Formation. A detailed sedimentation and tectonics study of the Coso Formation was undertaken to provide a more complete picture of the development of the Basin and Range province in this area. Detailed mapping and depositional analysis distinguishes separate northern and southern depocenters, each with its own accommodation and depositional history. While strata in both depocenters is disrupted by faults, these faults show modest displacement, and the intensity and magnitude of faulting does no t record significant extension. For this reason, the extension between the Sierran and Coso blocks is interpreted as minor in comparison to range bounding faults in adjacent areas of the Basin and Range.

  11. Constructing Hydraulic Barriers in Deep Geologic Formations

    SciTech Connect

    Carter, E.E.; Carter, P.E.; Cooper, D.C.

    2008-07-01

    Many construction methods have been developed to create hydraulic barriers to depths of 30 to 50 meters, but few have been proposed for depths on the order of 500 meters. For these deep hydraulic barriers, most methods are potentially feasible for soil but not for hard rock. In the course of researching methods of isolating large subterranean blocks of oil shale, the authors have developed a wax thermal permeation method for constructing hydraulic barriers in rock to depths of over 500 meters in competent or even fractured rock as well as soil. The technology is similar to freeze wall methods, but produces a permanent barrier; and is potentially applicable in both dry and water saturated formations. Like freeze wall barriers, the wax thermal permeation method utilizes a large number of vertical or horizontal boreholes around the perimeter to be contained. However, instead of cooling the boreholes, they are heated. After heating these boreholes, a specially formulated molten wax based grout is pumped into the boreholes where it seals fractures and also permeates radially outward to form a series of columns of wax-impregnated rock. Rows of overlapping columns can then form a durable hydraulic barrier. These barriers can also be angled above a geologic repository to help prevent influx of water due to atypical rainfall events. Applications of the technique to constructing containment structures around existing shallow waste burial sites and water shutoff for mining are also described. (authors)

  12. Acid Fracturing Feasibility Study for Heterogeneous Carbonate Formation 

    E-print Network

    Suleimenova, Assiya

    2015-03-03

    Acid fracturing is a stimulation technique that is commonly used by the industry to increase productivity or injectivity of wells in carbonate reservoirs. To determine a feasibility of acid fracturing treatment for a heterogeneous formation...

  13. Physical and geological processes of delta formation 

    E-print Network

    Bates, Charles Carpenter

    1953-01-01

    . Therefore, a strategy to aid cultural resource management (CRM) is needed. A geoscience strategy for CRM was developed by modifying engineering geological approaches. Evaluation of existing approaches revealed a common three or four phase strategy...

  14. Are geological media homogeneous or heterogeneous for neutron investigations?

    PubMed

    Wo?nicka, U; Drozdowicz, K; Gaba?ska, B; Krynicka, E; Igielski, A

    2003-01-01

    The thermal neutron absorption cross section of a heterogeneous material is lower than that of the corresponding homogeneous one which contains the same components. When rock materials are investigated the sample usually contains grains which create heterogeneity. The heterogeneity effect depends on the mass contribution of highly and low-absorbing centers, on the ratio of their absorption cross sections, and on their sizes. An influence of the granulation of silicon and diabase samples on the absorption cross section measured with Czubek's method has been experimentally investigated. A 20% underestimation of the absorption cross section has been observed for diabase grains of sizes from 6.3 to 12.8 mm. PMID:12485675

  15. A Laboratory Study of Heterogeneity and Scaling in Geologic Media

    NASA Astrophysics Data System (ADS)

    Brown, S.; Boitnott, G.; Bussod, G.; Hagan, P.

    2004-05-01

    In rocks and soils, the bulk geophysical and transport properties of the matrix and of fracture systems are determined by the juxtaposition of geometric features at many length scales. For sedimentary materials the length scales are: the pore scale (irregularities in grain surface roughness and cementation), the scale of grain packing faults (and the resulting correlated porosity structures), the scale dominated by sorting or winnowing due to depositional processes, and the scale of geomorphology at the time of deposition. We are studying the heterogeneity and anisotropy in geometry, permeability, and geophysical response from the pore (microscopic), laboratory (mesoscopic), and backyard field (macroscopic) scales. In turn these data are being described and synthesized for development of mathematical models. Eventually, we will perform parameter studies to explore these models in the context of transport in the vadose and saturated zones. We have developed a multi-probe physical properties scanner which allows for the mapping of geophysical properties on a slabbed sample or core. This device allows for detailed study of heterogeneity at those length scales most difficult to quantify using standard field and laboratory practices. The measurement head consists of a variety of probes designed to make local measurements of various properties, including: gas permeability, acoustic velocities (compressional and shear), complex electrical impedance (4 electrode, wide frequency coverage), and ultrasonic reflection (ultrasonic impedance and permeability). We can thus routinely generate detailed geophysical maps of a particular sample. We are testing and modifying these probes as necessary for use on soil samples. As a baseline study we have been characterizing the heterogeneity of a bench-size Berea sandstone block. Berea Sandstone has long been regarded as a laboratory standard in rock properties studies, owing to its uniformity and ``typical'' physical properties. We find that both permeability and velocity exhibit complex heterogeneity at the centimeter scale. While some correlation with the outcropping of the bedding is apparent, much of the heterogeneity is not clearly associated with visual features. For the study of soil heterogeneity at a wide range of scales, we are focusing on a local glacial deposit. This deposit is a glacial kame terrace of fluvial origin with multi-scale sedimentary structures comprised of unconsolidated sands, clays, and gravels. There are also many joints and faults in the unconsolidated sediments, allowing study of these as potential fluid flow conduits or barriers. We have obtained undisturbed soil samples from this site, allowing detailed laboratory study using similar methods to those described for the sandstone block.

  16. A Laboratory Study of Heterogeneity and Scaling in Geologic Media

    NASA Astrophysics Data System (ADS)

    Brown, S.; Boitnott, G.; Smith, M.

    2003-12-01

    In rocks and soils, the bulk geophysical and transport properties of the matrix and of fracture systems are determined by the juxtaposition of geometric features at many length scales. For sedimentary materials the length scales are: the pore scale (irregularities in grain surface roughness and cementation), the scale of grain packing faults (and the resulting correlated porosity structures), the scale dominated by sorting or winnowing due to depositional processes, and the scale of geomorphology at the time of deposition. We are studying the heterogeneity and anisotropy in geometry, permeability, and geophysical response from the pore (microscopic), laboratory (mesoscopic), and backyard field (macroscopic) scales. In turn these data are being described and synthesized for development of mathematical models. Eventually, we will perform parameter studies to explore these models in the context of transport in the vadose and saturated zones. We have developed a multi-probe physical properties scanner which allows for the mapping of geophysical properties on a slabbed sample or core. This device allows for detailed study of heterogeneity at those length scales most difficult to quantify using standard field and laboratory practices. The measurement head consists of a variety of probes designed to make local measurements of various properties, including: gas permeability, acoustic velocities (compressional and shear), complex electrical impedance (4 electrode, wide frequency coverage), and ultrasonic reflection (ultrasonic impedance and permeability). We can thus routinely generate detailed geophysical maps of a particular sample. With the exception of the acoustic velocity, we are testing and modifying these probes as necessary for use on soil samples. As a baseline study we have been characterizing the heterogeneity of a bench-size Berea sandstone block. Berea Sandstone has long been regarded as a laboratory standard in rock properties studies, owing to its uniformity and ``typical'' physical properties. We find that both permeability and velocity exhibit complex heterogeneity at the centimeter scale. While some correlation with the outcropping of the bedding is apparent, much of the heterogeneity is not clearly associated with visual features. For the study of soil heterogeneity at a wide range of scales, we are focusing on a local glacial deposit. This deposit is a glacial kame terrace of fluvial origin with multi-scale sedimentary structures comprised of unconsolidated sands, clays, and gravels. There are also many joints and faults in the unconsolidated sediments, allowing study of these as potential fluid flow conduits or barriers. We have obtained undisturbed soil samples from this site, allowing detailed laboratory study using similar methods to those described for the sandstone block.

  17. Multiblock Grid Generation for Simulations in Geological Formations

    E-print Network

    Sanjay Kumar Khattri

    2006-07-17

    Simulating fluid flow in geological formations requires mesh generation, lithology mapping to the cells, and computing geometric properties such as normal vectors and volume of cells. The purpose of this research work is to compute and process the geometrical information required for performing numerical simulations in geological formations. We present algebraic techniques, named Transfinite Interpolation, for mesh generation. Various transfinite interpolation techniques are derived from 1D projection operators. Many geological formations such as the Utsira formation (Torp and Gale, 2004; Khattri, Hellevang, Fladmark and Kvamme, 2006) and the Snohvit gas field (Maldal and Tappel, 2004) can be divided into layers or blocks based on the geometrical or lithological properties of the layers. We present the concept of block structured mesh generation for handling such formations.

  18. Petroleum geology of the Vicksburg Formation, Texas

    SciTech Connect

    Coleman, J.; Galloway, W.E. )

    1990-09-01

    The Late Oligocene Vicksburg Formation of the Texas Gulf Coastal Plain lies within the Tertiary depositional wedge between the Upper Eocene Jackson Group and the Upper Oligocene Frio-Catahoula Formations. Across the state of Texas there are a total of 351 fields producing from the Vicksburg Formation; as of 1 January 1982, these fields had produced cumulative totals of 73.5 million barrels of oil, 4 million barrels of condensate, and 274 billion cubic feet of gas. In the Rio Grande Embayment of South Texas, the Vicksburg Formation has long been recognized as a prolific petroleum producer from shelf-edge delta sand reservoirs. In the Houston Embayment of the eastern Texas coastal plain, the Vicksburg producing sands were deposited in a deltaic systems tract positioned on the relict Jackson shelf platform. Regional depositional systems analysis of the Central Texas Vicksburg Formation has demonstrated that this unit is dominated by a belt composed of a strike-oriented paralic sand complex. The depositional environments responsible for these interrelated coastal sands include delta flanks and their associated shorezone, strand plain, and barrier systems. These paralic sands are the lateral equivalent of the Vicksburg deltaic system in the Houston Embayment and of the extensively growth-faulted deltas within the Rio Grande Embayment. Across the Texas coast, the fields producing from the Vicksburg are associated with the Vicksburg Growth Fault Zone. The reservoirs are most commonly found in the uppermost sands of the deltaic sections; the porosity is usually secondary, controlled by diagenesis. Most of the fields have anticlinal closure or a structural-stratigraphic combination trapping situation.

  19. Stochastic Modeling of Macrodispersion in Variably Saturated, Spatially Heterogeneous Formations

    NASA Astrophysics Data System (ADS)

    Russo, David

    2015-04-01

    The macrodispersion tensor, D, plays an important role in solute transport on the field scale. A key problem is how to relate D to the properties of the spatially heterogeneous formation. Under unsaturated flow conditions, the problem is further complicated inasmuch as the relevant flow parameters, the hydraulic conductivity and the water capacity, which depend on the formation properties, depend also on flow-controlled attributes in a highly nonlinear fashion. Consequently, under variably saturated conditions, quantification of D requires several simplifying assumptions regarding the constitutive relationships for unsaturated flow, the flow regime, and the spatial structure of the formation heterogeneity. The present talk focuses on the quantification of D in a variably saturated, spatially heterogeneous formation, accomplished by using a two-stage approach. The approach combines a stochastic, continuum description of a steady-state unsaturated flow, based on small-perturbation, first-order approximation of Darcy's law and the continuity equation for unsaturated flow, with a general Lagrangian description of the motion of an indivisible particle of a passive solute that is carried by the steady-state flow. The resultant, time-dependent D depends on the covariances of the water saturation and the components of the water flux vector, and their cross-covariances, which, in turn, depend on the (cross-)covariances of the relevant formation properties and the pressure head. The effect of few characteristics of the spatially heterogeneous, variably saturated flow system, on D is analyzed and discussed. Main findings reveal that under variably saturated flow conditions, the travel distance required for the principal components of D to approach their asymptotic values may be exceedingly large, particularly in relatively wet formations with significant stratification and with coarse-textured soil material associated with small capillary forces. Hence, in many practical situations of vadose-zone transport, the typical travel distance, may be small compared with the travel distance required for D to reach its asymptotic, Fickian behavior.

  20. DISPOSAL METHODS: LANDFILLS, GEOLOGIC FORMATIONS, CHEMICAL STABILIZATION, AND CHEMICAL TREATMENT

    EPA Science Inventory

    The section will deal with four hazardous waste disposal options, i.e., landfills, geologic formations, chemical stabilization, and chemical treatment. Landfilling has been the traditional method of disposing of hazardous waste. Improper land disposal has led to numerous cases of...

  1. Heterogeneity and subjectivity in binary-state opinion formation systems

    NASA Astrophysics Data System (ADS)

    Guo, Long; Luo, Zhongjie; Zhu, Yueying

    2013-11-01

    In society, there is heterogeneous interaction and randomness in human decision making. In order to unfold the roles and the competition of the two factors mentioned above in opinion formation, we propose a toy model, which follows a majority rule with a Fermi function, on scale-free networks with degree exponent ?. The heterogeneous interaction is related to the connectivity of a person with the interactive parameter ?, and the randomness of human decision making is quantified by the interaction noise T. We find that a system with heterogeneity of network topology and interaction shows robustness perturbed by the interaction noise T according to the theoretical analysis and numerical simulation. Then, when T ? 0, the homogeneous interaction (? ? 0) has a powerful implication for the emergence of a consensus state. Furthermore, the emergence of the two extreme values shows the competition of the heterogeneity of interaction and the subjectivity of human decision making in opinion formation. Our present work provides some perspective on and tools for understanding the diversity of opinion in our society.

  2. Using mesoscale modeling to investigate the role of material heterogeneity in geologic and planetary materials.

    SciTech Connect

    Crawford, David A.

    2005-08-01

    The propagation of shock waves through target materials is strongly influenced by the presence of small-scale structure, fractures, physical and chemical heterogeneities. Reverberations behind the shock from the presence of physical heterogeneity have been proposed as a mechanism for transient weakening of target materials as are localized shock effects seen in some meteorites. Pre-existing fractures can also affect melt generation. Recent mesoscale studies in computational hydrodynamics have attempted to bridge the gap in numerical modeling between the microscale and the continuum,. Methods are being devised using shock physics hydrocodes such as CTH and Monte-Carlo-type methods to investigate the shock properties of heterogeneous materials and to compare the results with experiments. Recent numerical experiments at the mesoscale using these statistical methods suggest that heterogeneity at the micro-scale plays a substantial and statistically quantifiable role in the effective shear and fracture strength of rocks. This paper will describe the methodology we are using to determine the strength of heterogeneous geologic and planetary materials.

  3. Geological pattern formation by growth and dissolution in aqueous systems

    SciTech Connect

    Paul Meakin

    2010-03-01

    Although many geological processes take place on time scales that are very long compared with the human experience, essentially all geological processes, fast or slow, are far from equilibrium processes. Surprisingly often, geological processes lead to the formation of quite simple and distinctive patterns, which hint at an underlying simplicity in many complex geological systems.. The ability to predict the seasons was critically important to early human society, and Halley’s prediction of the return of the comet that bears his name is still considered to be a scientific milestone. Spatial patterns have also attracted attention because of their aesthetic appeal, which depends in subtle ways on a combination of regularity and irregularity. In recent decades, rapid growth in the capabilities of digital computers has facilitated the simulation of pattern formation processes, and computer simulations have become an important tool for evaluating theoretical concepts and for scientific discovery. Computer technology in combination with other technologies such as high resolution digital cameras, scanning microprobes (atomic force microscopy AFM), confocal microscopy, and scanning tunneling microscopy (STM), for example) has facilitated the quantitative characterization of patterns over a wide range of scales and has enabled rapid advances in our ability to understand the links between large scale pattern formation and microscopic processes. The ability to quantitatively characterize patterns is important because it enables a more rigorous comparison between the predictions of computer models and real world patterns and their formation.In some cases, the idea that patterns with a high degree of regularity have simple origins appears to be justified, but in other cases, such as the formation of almost perfectly circular stone rings due to freeze-thaw cycles simple patterns appear to be the consequence of quite complex processes. In other cases, it has been shown that very simple non-linear processes can lead to extremely complicated patterns, and that some apparently complex disordered systems can be described quantitatively in terms of simple fractal models.

  4. Vertical stratification of subsurface microbial community composition across geological formations at the Hanford Site

    SciTech Connect

    Lin, Xueju; Kennedy, David W.; Fredrickson, Jim K.; Bjornstad, Bruce N.; Konopka, Allan

    2012-02-01

    The microbial diversity in subsurface sediments at the Hanford Site's 300 Area in southeastern Washington State was investigated by analyzing 21 samples recovered from depths that ranged from 9 to 52 m. Approximately 8000 non-chimeric Bacterial and Archaeal 16S rRNA gene sequences were analyzed across geological strata that contain a natural redox transition zone. These strata included the oxic coarse-grained Hanford formation, fine-grained oxic and anoxic Ringold Formation sediments, and the weathered basalt group. We detected 1233 and 120 unique bacterial and archaeal OTUs (Operational Taxonomic Units, defined at the 97% identity level). Microbial community structure and richness varied substantially across the different geological strata. Bacterial OTU richness (based upon Chao1 estimator) was highest (>700) in the upper Hanford formation, and declined to about 120 at the bottom of the Hanford formation. Just above the Ringold oxic-anoxic transition zone, richness was about 325 and declined to less than 50 in the deeper reduced zones. The Bacterial community in the oxic Hanford and Ringold Formations contained members of 9 major well-recognized phyla as well 30 as unusually high proportions of 3 candidate divisions (GAL15, NC10, and SPAM). The deeper Ringold strata were characterized by low OTU richness and a very high preponderance (ca. 90%) of Proteobacteria. The study has greatly expanded the intralineage phylogenetic diversity within some major divisions. These subsurface sediments have been shown to contain a large number of phylogenetically novel microbes, with substantial heterogeneities between sediment samples from the same geological formation.

  5. Role of particulate metals in heterogenous secondary sulfate formation

    NASA Astrophysics Data System (ADS)

    Clements, Andrea L.; Buzcu-Guven, Birnur; Fraser, Matthew P.; Kulkarni, Pranav; Chellam, Shankararaman

    2013-08-01

    A series of field sampling and controlled laboratory experiments were undertaken to quantify the role of trace metals found in ambient fine particulate matter and metal-rich primary sources in the heterogenous catalytic conversion of SO2 gas into sulfate particulate matter (PM) in the atmosphere. Analysis produced source profiles of three primary source materials, fluidized-bed catalytic cracking catalyst, coal-fired combustion fly ash, and paved road dust, featuring 33 elements including rare earth metals, which are not commonly reported in the literature. Subsequently three sets of experiments were conducted exposing 1) source materials, 2) ambient PM, and 3) ambient PM augmented with approximately an equal amount of source material to SO2 gas and measuring sulfate formation. Source material experiments revealed that the greatest extent of reaction was on the surface of coal fly ash with sulfate formation of 19 ± 5 mg sulfate g-1 material. Ambient fine particulate matter (PM) experiments showed sulfate formation ranging from negligible amounts to 180 ± 10 mg sulfate g-1 PM. It was much more difficult to quantify the sulfate formation on ambient filters augmented with the source materials. In these experiments, sulfate formation ranged from negligible amounts to 40 ± 8 mg sulfate g-1 of particles (ambient + augmented material). These three sets of experiments shows that heterogenous sulfate formation is often negligible but, under some conditions can contribute 10% or more to the total sulfate concentrations when exposed to high SO2 concentrations such as those found in plumes. Factor analysis of the source material experiments grouped metals into two categories, crustal components and anthropogenically emitted metals representative of catalyst material, with the former showing the strongest correlation with sulfate formation. Subsequent analysis of data collected from the ambient PM experiments showed a much weaker correlation of sulfate formation with the crustal components, including iron and titanium, remaining clustered with sulfate formation. Independent research has been previously reported in the literature establishing mechanisms for the iron and titanium catalyzed conversion of S(IV) to S(VI) suggesting there may be other metals within these crustal type metal components that behave similarly. Additional experiments spanning a wider range of variables including more sources, SO2 concentrations and exposure times, ambient PM locations, as well as more individual samples may be necessary to obtain more conclusive evidence into the role of various metals in catalyzing the conversion of S(IV) to S(VI).

  6. Large-scale characterization of geologic formations for CO2 injection using Compressed State Kalman Filter

    NASA Astrophysics Data System (ADS)

    Kokkinaki, A.; Li, J. Y.; Zhou, Q.; Birkholzer, J. T.; Kitanidis, P. K.

    2014-12-01

    Carbon dioxide (CO2) storage in deep geologic formations is gaining ground as a potential measure for climate change mitigation. Such storage projects typically operate at large scales (~km), but their performance is often governed by smaller-scale (~m) heterogeneities. The large domain sizes prohibit detailed site characterization and dense monitoring networks, leading to predictions of CO2 migration and trapping based on rough geologic models that cannot capture preferential flow. Kalman Filtering can be used to improve these prior models by assimilating available monitoring data, thereby tracking system performance and reducing prediction uncertainty. However, for large systems with fine discretization, the number of unknowns is in the order of tens of thousands or more, in which case the textbook version of the Kalman Filter has prohibitively expensive computation and storage costs. We present the Compressed State Kalman Filter (CSKF) that can be effectively used for systems with a large number of unknowns to estimate the underlying heterogeneity and to predict the state of interest (e.g., pressure and CO2 saturation). The algorithm's computational efficiency is achieved by using a low-rank approximation of the covariance matrix, as well as a Jacobian-free approach. We demonstrate the estimation and computational performance of our method in a typical CO2 storage scenario with a spatially sparse monitoring network, but with multiple datasets obtained before and during CO2 injection. Our data assimilation framework provides an efficient and practical way to characterize geological formations intended for CO2 injection and storage using monitoring data commonly collected in field applications, as well as to quantify the reduction in uncertainty brought by different types of monitoring data.

  7. Photoacoustic Signal Formation in Heterogeneous Multilayer Systems with Piezoelectric Detection

    NASA Astrophysics Data System (ADS)

    Isaiev, Mykola; Andrusenko, Dmytro; Tytarenko, Alona; Kuzmich, Andrey; Lysenko, Vladimir; Burbelo, Roman

    2014-12-01

    A new efficient model describing photoacoustic (PA) signal formation with piezoelectric detection is reported. Multilayer sandwich-like systems: heterogeneous studied structure—buffer layer—piezoelectric transducers are considered. In these systems, the buffer layer is used for spatial redistribution of thermoelastic force moments generated in the investigated structure. Thus, mechanical properties of this layer play a crucial role to ensure perfect control of the detected voltage formed on a piezoelectric transducer by contribution of different regions of the studied structure. In particular, formation of the voltage signal strongly depends on the point at which the thermoelastic source is applied. Therefore, use of relatively simple linear Green's functions introduced in frames of the Kirchhoff-Love theory is chosen as an efficient approach for the PA signal description. Moreover, excellent agreement between the theoretical model and measured results obtained on a heterogeneous "porous silicon-bulk Si substrate" structure is stated. Furthermore, resolving of the inverse problem with fitting of the experimental curves by the developed model allows reliable evaluation of the thermal conductivity of the nanostructured porous silicon layer.

  8. Geological and biological heterogeneity of the Aleutian margin (1965-4822 m)

    NASA Astrophysics Data System (ADS)

    Rathburn, A. E.; Levin, L. A.; Tryon, M.; Gieskes, J. M.; Martin, J. B.; Pérez, M. E.; Fodrie, F. J.; Neira, C.; Fryer, G. J.; Mendoza, G.; McMillan, P. A.; Kluesner, J.; Adamic, J.; Ziebis, W.

    2009-01-01

    Geological, biological and biogeochemical characterization of the previously unexplored margin off Unimak Island, Alaska between 1965 and 4822 m water depth was conducted to examine: (1) the geological processes that shaped the margin, (2) the linkages between depth, geomorphology and environmental disturbance in structuring benthic communities of varying size classes and (3) the existence, composition and nutritional sources of methane seep biota on this margin. The study area was mapped and sampled using multibeam sonar, a remotely operated vehicle (ROV) and a towed camera system. Our results provide the first characterization of the Aleutian margin mid and lower slope benthic communities (microbiota, foraminifera, macrofauna and megafauna), recognizing diverse habitats in a variety of settings. Our investigations also revealed that the geologic feature known as the “Ugamak Slide” is not a slide at all, and could not have resulted from a large 1946 earthquake. However, sediment disturbance appears to be a pervasive feature of this margin. We speculate that the deep-sea occurrence of high densities of Elphidium, typically a shallow-water foraminiferan, results from the influence of sediment redeposition from shallower habitats. Strong representation of cumacean, amphipod and tanaid crustaceans among the Unimak macrofauna may also reflect sediment instability. Although some faunal abundances decline with depth, habitat heterogeneity and disturbance generated by canyons and methane seepage appear to influence abundances of biota in ways that supercede any clear depth gradient in organic matter input. Measures of sediment organic matter and pigment content as well as C and N isotopic signatures were highly heterogeneous, although the availability of organic matter and the abundance of microorganisms in the upper sediment (1-5 cm) were positively correlated. We report the first methane seep on the Aleutian slope in the Unimak region (3263-3285 m), comprised of clam bed, pogonophoran field and carbonate habitats. Seep foraminiferal assemblages were dominated by agglutinated taxa, except for habitats above the seafloor on pogonophoran tubes. Numerous infaunal taxa in clam bed and pogonophoran field sediments and deep-sea “reef” cnidarians (e.g., corals and hydroids) residing on rocks near seepage sites exhibited light organic ? 13C signatures indicative of chemosynthetic nutritional sources. The extensive geological, biogeochemical and biological heterogeneity as well as disturbance features observed on the Aleutian slope provide an attractive explanation for the exceptionally high biodiversity characteristic of the world’s continental margins.

  9. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Final report

    SciTech Connect

    Menzie, D.E.

    1995-05-01

    The main objective of this research project is to investigate dispersion as a method of quantifying geological characterization and defining reservoir heterogeneity in order to enhance crude oil recovery. The dispersion of flow of a reservoir rock (dispersion coefficient and dispersivity) was identified as one of the physical properties of a reservoir rock by measuring the mixing of two miscible fluids, one displacing the other in a porous medium. A rock was 100% saturated with a resident fluid and displaced by a miscible fluid of equal viscosity and equal density. Some specific experiments were performed with unequal densities. Produced fluid was analyzed by refractometer, nuclear reaction, electrical conductivity and X-ray scan. Several physical and flow characteristics were measured on the sand rock sample in order to establish correlations with the measured dispersion property. Absolute permeability, effective porosity, relative permeability, capillary pressure, the heterogeneity factor and electrical conductivity were used to better understand the flow system. Linear, transverse, 2-D and 3-D dispersions were measured and used to characterize the rock heterogeneity of the flow system. A new system of measuring dispersion was developed using a gas displacing gas system in a porous medium. An attempt was also made to determine the dispersion property of an actual reservoir from present day well log data on a producing well. 275 refs., 102 figs., 17 tabs.

  10. Background seismicity controlled by heterogeneity in subsurface geology: An example from the Wakayama region, southwest Japan

    NASA Astrophysics Data System (ADS)

    Maeda, S.; Toda, S.; Katao, H.

    2013-12-01

    Heterogeneity associated with shallow geologic structure is one of the factors to control the earthquake occurrence in the crust. Material properties properties such as strength, permeability, fluid content, and rheology, reflected from different lithological units may influence faulting behavior, thus seismicity. To explore the role of geologic heterogeneity into the seismicity, here we examine the spatial relationship between seismicity and geologic structure in the Wakayama region, northwestern Kii Peninsula, in which a significant high background rate of seismicity has been continuously recorded since the mid-1900 (~100 M?2.0 earthquakes recorded per year since 2000). Epicenters of numerous small earthquakes are located mainly on the Mesozoic metamorphic rocks and accretion units bounded by major tectonic lines, which dimension is roughly ~40 km x ~40 km (hereinafter 'Wakayama seismic zone'). Within the Wakayama seismic zone, we observe many E-W and ENE-WSW trending dense seismic clusters plotted by the Japan Meteorological Agency (JMA) catalog. To see finer internal hypocenter distribution particularly characteristics of the seismic clusters, we employed the hypoDD method (Waldhauser and Ellsworth, 2000) to relocate the JMA hypocenters. Our hypoDD catalog made the clouds of clusters much sharper and enables us to compare with the detail and local geologic structure. We found that most of the E-W trending seismic clusters possibly correspond to the E-W trending local scale geologic faults, folds, bedding planes, and schistosity. We also found that there are two ~15-km-long and ~5-km-wide aseismic zones that are well corresponding to mafic to ultramafic rocks including serpentine (called 'Mikabu zone'). The Mikabu zones are also well expressed by the high Bouguer anomalies (Geological Survey of Japan, 2013). Employing Talwani model (Talwani, 1959), we estimated that higher density ultra-mafic rocks extended up to 5 km deep from the surface. We interpret that either high shear modulus (stronger) or less ductile property of ultra-mafic rocks dominate aseismic behavior. Unlike such significant E-W striking features, however, well-determined fault plane solutions by JMA and the National Research Institute for Earth Science and Disaster Prevention (NIED) show NS-trending reverse faults corresponding to EW compression. To resolve the inconsistency between the seismic trend and dominant fault strike, we further sought the focal mechanisms for smaller earthquakes using waveform data (P-wave first motion polarites) recorded in the SATARN seismic network system of DPRI, Kyoto University. As a result, among the many reverse fault mechanisms, we found some amounts of strike-slip ones, which may associate with the visible EW-trending seismic clusters. A few normal faulting solutions also suggest that local heterogeneity in stress and strength along the N-E trending geologic features originated from subduction accretional tectonics.

  11. Geology of the Biwabik Iron Formation and Duluth Complex

    USGS Publications Warehouse

    Jirsa, M.A.; Miller, J.D., Jr.; Morey, G.B.

    2008-01-01

    The Biwabik Iron Formation is a ???1.9 billion year-old sequence of iron-rich sedimentary rocks that was metamorphosed at its eastern-most extent by ???1.1 billion year-old intrusions of the Duluth Complex. The metamorphic recrystallization of iron-formation locally produced iron-rich amphiboles and other fibrous iron-silicate minerals. The presence of these minerals in iron-formation along the eastern part of what is known as the Mesabi Iron Range, and their potential liberation by iron mining has raised environmental health concerns. We describe here the geologic setting and mineralogic composition of the Biwabik Iron Formation in and adjacent to the contact metamorphic aureole of the Duluth Complex. The effects of metamorphism are most pronounced within a few kilometers of the contact, and decrease progressively away from it. The contact aureole has been divided into four metamorphic zones-each characterized by the composition and crystal structure of the metamorphic minerals it contains. The recrystallization of iron-formation to iron-rich amphibole minerals (grunerite and cummingtonite) and iron-pyroxene minerals (hedenbergite and ferrohypersthene) is best developed in zones that are most proximal to the Duluth Complex contact. ?? 2007 Elsevier Inc. All rights reserved.

  12. Geology of the Biwabik Iron Formation and Duluth Complex.

    PubMed

    Jirsa, Mark A; Miller, James D; Morey, G B

    2008-10-01

    The Biwabik Iron Formation is a approximately 1.9 billion year-old sequence of iron-rich sedimentary rocks that was metamorphosed at its eastern-most extent by approximately 1.1 billion year-old intrusions of the Duluth Complex. The metamorphic recrystallization of iron-formation locally produced iron-rich amphiboles and other fibrous iron-silicate minerals. The presence of these minerals in iron-formation along the eastern part of what is known as the Mesabi Iron Range, and their potential liberation by iron mining has raised environmental health concerns. We describe here the geologic setting and mineralogic composition of the Biwabik Iron Formation in and adjacent to the contact metamorphic aureole of the Duluth Complex. The effects of metamorphism are most pronounced within a few kilometers of the contact, and decrease progressively away from it. The contact aureole has been divided into four metamorphic zones-each characterized by the composition and crystal structure of the metamorphic minerals it contains. The recrystallization of iron-formation to iron-rich amphibole minerals (grunerite and cummingtonite) and iron-pyroxene minerals (hedenbergite and ferrohypersthene) is best developed in zones that are most proximal to the Duluth Complex contact. PMID:17997209

  13. Geologically based model of heterogeneous hydraulic conductivity in an alluvial setting

    NASA Astrophysics Data System (ADS)

    Fogg, Graham E.; Noyes, Charles D.; Carle, Steven F.

    Information on sediment texture and spatial continuity are inherent to sedimentary depositional facies descriptions, which are therefore potentially good predictors of spatially varying hydraulic conductivity (K). Analysis of complex alluvial heterogeneity in Livermore Valley, California, USA, using relatively abundant core descriptions and field pumping-test data, demonstrates a depositional-facies approach to characterization of subsurface heterogeneity. Conventional textural classifications of the core show a poor correlation with K; however, further refinement of the textural classifications into channel, levee, debris-flow, and flood-plain depositional facies reveals a systematic framework for spatial modeling of K. This geologic framework shows that most of the system is composed of very low-K flood-plain materials, and that the K measurements predominantly represent the other, higher-K facies. Joint interpretation of both the K and geologic data shows that spatial distribution of K in this system could not be adequately modeled without geologic data and analysis. Furthermore, it appears that K should not be assumed to be log-normally distributed, except perhaps within each facies. Markov chain modeling of transition probability, representing spatial correlation within and among the facies, captures the relevant geologic features while highlighting a new approach for statistical characterization of hydrofacies spatial variability. The presence of fining-upward facies sequences, cross correlation between facies, as well as other geologic attributes captured by the Markov chains provoke questions about the suitability of conventional geostatistical approaches based on variograms or covariances for modeling geologic heterogeneity. Résumé Les informations sur la texture des sédiments et leur continuité spatiale font partie des descriptions de faciès sédimentaires de dépôt. Par conséquent, ces descriptions sont d'excellents prédicteurs potentiels des variations spatiales de la conductivité hydraulique (K). L'analyse de l'hétérogénéité des alluvions complexes de la vallée de Livermore (Californie, États-Unis), sur la base de descriptions de carottes relativement nombreuses et de données d'essais de pompage, montre que l'hétérogénéité souterraine peut être caractérisée par une approche des faciès de dépôt. Des classifications conventionnelles de la texture de la carotte montrent une corrélation médiocre avec K; toutefois, une amélioration ultérieure des classifications de texture en faciès de dépôt de chenal, de levée d'inondation, de coulée boueuse et de plaine d'inondation a fourni un cadre systématique pour une modélisation spatiale de K. Ce cadre géologique montre que le système est composé pour l'essentiel par des matériaux d'inondation à très faible perméabilité ceci laisse envisager qu'on ne peut pas supposer que K suit une distribution log-normal, sauf peut-être à l'intérieur de chaque faciès. Une modélisation par chaîne de Markov de la probabilité de passage, représentant la corrélation spatiale dans les faciès et entre eux, prend en compte les faits géologiques intéressants tout en fournissant une approche nouvelle pour une caractérisation statistique de la variabilité spatiale des faciès. La présence de séquences à faciès tronqués vers le haut, d'une corrélation croisée entre faciès, ainsi que d'autres caractères géologiques pris en compte par les chaînes de Markov conduisent à se poser des questions sur l'adéquation des approches géostatistiques conventionnelles utilisant les variogrammes ou les covariances pour modéliser l'hétérogénéité géologique. Resumen La información respecto a la textura de los sedimentos y la continuidad espacial es inherente a las descripciones de las facies deposicionales sedimentarias. De este modo, estas descripciones se convierten en excelentes predictores potenciales de las variaciones espaciales de la conductividad hidráulica (K). El análisis de la heterogeneidad en un aluvial en el Valle de L

  14. Estimation of hydrologic properties of heterogeneous geologic media with an inverse method based on iterated function systems

    SciTech Connect

    Doughty, C.A.

    1996-05-01

    The hydrologic properties of heterogeneous geologic media are estimated by simultaneously inverting multiple observations from well-test data. A set of pressure transients observed during one or more interference tests is compared to the corresponding values obtained by numerically simulating the tests using a mathematical model. The parameters of the mathematical model are varied and the simulation repeated until a satisfactory match to the observed pressure transients is obtained, at which point the model parameters are accepted as providing a possible representation of the hydrologic property distribution. Restricting the search to parameters that represent fractal hydrologic property distributions can improve the inversion process. Far fewer parameters are needed to describe heterogeneity with a fractal geometry, improving the efficiency and robustness of the inversion. Additionally, each parameter set produces a hydrologic property distribution with a hierarchical structure, which mimics the multiple scales of heterogeneity often seen in natural geological media. Application of the IFS inverse method to synthetic interference-test data shows that the method reproduces the synthetic heterogeneity successfully for idealized heterogeneities, for geologically-realistic heterogeneities, and when the pressure data includes noise.

  15. Elastic and plastic effects on heterogeneous nucleation and nanowire formation

    NASA Astrophysics Data System (ADS)

    Boussinot, G.; Schulz, R.; Hüter, C.; Brener, E. A.; Spatschek, R.

    2014-02-01

    We investigate theoretically the effects of elastic and plastic deformations on heterogeneous nucleation and nanowire formation. In the first case, the influence of the confinement of the critical nucleus between two parallel misfitting substrates is investigated using scaling arguments. We present phase diagrams giving the nature of the nucleation regime as a function of the driving force and the degree of confinement. We complement this analytical study by amplitude equations simulations. In the second case, the influence of a screw dislocation inside a nanowire on the development of the morphological surface instability of the wire, related to the Rayleigh-Plateau instability, is examined. Here the screw dislocation provokes a torsion of the wire known as Eshelby twist. Numerical calculations using the finite element method and the amplitude equations are performed to support analytical investigations. It is shown that the screw dislocation promotes the Rayleigh-Plateau instability.

  16. Sulfuric Acid Monohydrate: Formation and Heterogeneous Chemistry in the Stratosphere

    NASA Technical Reports Server (NTRS)

    Zhang, Renyi; Leu, Ming-Taun; Keyser, Leon F.

    1995-01-01

    We have investigated some thermodynamic properties (i.e., freezing/melting points) and heterogeneous chemistry of sulfuric acid monohydrate (SAM, H2SO4.H2O), using a fast flow reactor coupled to a quadrupole mass spectrometer. The freezing point observations of thin liquid sulfuric acid films show that for acid contents between 75 and 85 wt % the monohydrate crystallizes readily at temperatures between 220 and 240 K on a glass substrate. Once formed, SAM can be thermodynamically stable in the H2O partial pressure range of (1-4) x 10(exp -4) torr and in the temperature range of 220-240 K. For a constant H2O partial pressure, lowering the temperature causes SAM to melt when the temperature and water partial pressure conditions are out of its stability regime. The reaction probability measurements indicate that the hydrolysis of N2O5 is significantly suppressed owing to the formation of crystalline SAM: The reaction probability on water-rich SAM (with higher relative humidity, or RH) is of the order of 10(exp -3) at 210 K and decreases by more than an order of magnitude for the acid-rich form (with lower RH). The hydrolysis rate of ClONO2 on water-rich SAM is even smaller, of the order of 10(exp -4) at 195 K. These reported values on crystalline SAM are much smaller than those on liquid solutions. No enhancement of these reactions is observed in the presence of HCl vapor at the stratospheric concentrations. In addition, Brunauer, Emmett, and Teller analysis of gas adsorption isotherms and photomicrography have been performed to characterize the surface roughness and porosities of the SAM substrate. The results suggest the possible formation of SAM in some regions of the middle- or low-latitude stratosphere and, consequently, much slower heterogeneous reactions on the frozen aerosols.

  17. Determining resistivity of a geological formation using circuitry located within a borehole casing

    DOEpatents

    Vail III, William Banning

    2006-01-17

    Geological formation resistivity is determined. Circuitry is located within the borehole casing that is adjacent to the geological formation. The circuitry can measure one or more voltages across two or more voltage measurement electrodes associated with the borehole casing. The measured voltages are used by a processor to determine the resistivity of the geological formation. A common mode signal can also be reduced using the circuitry.

  18. Establishment of an oil and gas database for increased recovery and characterization of oil and gas carbonate reservoir heterogeneity. [Jurassic Smackover Formation

    SciTech Connect

    Mancini, E.A.

    1990-01-01

    The objective of this project is to augment the National Reservoir Database (TORIS database), to increase our understanding of geologic heterogeneities that affect the recoveries of oil and gas from carbonate reservoirs in the State of Alabama, and to identify resources that are producible at moderate cost. This objective will be achieved through detailed geological, geostatistical, and engineering characterization of typical Jurassic Smackover Formation hydrocarbon, and engineering characterization of typical Jurassic Smackover Formation hydrocarbon reservoirs in selected productive fields in the state of Alabama. The results of these studies will be used to develop and test mathematical models for prediction of the effects of reservoir heterogeneities in hydrocarbon production. Work to date has focused on completion of Subtasks 1, 2, and 3 of this project. Work on Subtask 4 began in this quarter, and substantial additional work has been accomplished on Subtask 2. Subtask 1 included the survey and tabulation of available reservoir engineering and geological data. Subtask 2 comprises the geologic and engineering characterization of smackover reservoir lithofacies. Subtask 3 includes the geologic modeling of reservoir heterogeneities. Subtask 4 includes the development of reservoir exploitation methodologies for strategic infill drilling. 1 fig.

  19. Heterogeneity and Scaling in Geologic Media: Applications to Transport in the Vadose and Saturated Zones

    SciTech Connect

    Brown, Stephen R.

    2003-06-01

    Heterogeneity and Scaling in Geologic Media: Applications to Transport in the Vadose and Saturated Zones Stephen Brown, Gregory Boitnott, and Martin Smith New England Research In rocks and soils, the bulk geophysical and transport properties of the matrix and of fracture systems are determined by the juxtaposition of geometric features at many length scales. For sedimentary materials the length scales are: the pore scale (irregularities in grain surface roughness and cementation), the scale of grain packing faults (and the resulting correlated porosity structures), the scale dominated by sorting or winnowing due to depositional processes, and the scale of geomorphology at the time of deposition. We are studying the heterogeneity and anisotropy in geometry, permeability, and geophysical response from the pore (microscopic), laboratory (mesoscopic), and backyard field (macroscopic) scales. In turn these data are being described and synthesized for development of mathematical models. Eventually, we will perform parameter studies to explore these models in the context of transport in the vadose and saturated zones. We have developed a multi-probe physical properties scanner which allows for the mapping of geophysical properties on a slabbed sample or core. This device allows for detailed study of heterogeneity at those length scales most difficult to quantify using standard field and laboratory practices. The measurement head consists of a variety of probes designed to make local measurements of various properties, including: gas permeability, acoustic velocities (compressional and shear), complex electrical impedance (4 electrode, wide frequency coverage), and ultrasonic reflection (ultrasonic impedance and permeability). We can thus routinely generate detailed geophysical maps of a particular sample. With the exception of the acoustic velocity, we are testing and modifying these probes as necessary for use on soil samples. As a baseline study we have been characterizing the heterogeneity of a bench-size Berea Sandstone block. Berea Sandstone has long been regarded as a laboratory standard in rock properties studies, owing to its uniformity and ''typical'' physical properties. We find that both permeability and velocity exhibit complex heterogeneity at the centimeter scale. While some correlation with the outcropping of the bedding is apparent, much of the heterogeneity is not clearly associated with visual features. We are developing software tools to examine simultaneously pixel by pixel correlations among geophysical measurements, transport properties, and visual (photographic) texture and the dependence of these correlations on measurement scale. We find that certain pairs of physical quantities, such as P velocity and permeability for example, are distinctly correlated with one another at certain scales, but less obviously at other scales. Preliminary analyses of the Berea Sandstone data show that by simultaneous consideration of several physical properties the data can be separated into clusters of like properties which can be considered distinct facies. Apparently, identification of these facies, which could represent a limited range of fluid permeability, may be made by making joint geophysical measurements. Given various physical models for the dependence of the geophysical and transport properties on pore size, we expect that these observed correlations will provide conditioning and constraints to inversions for stochastic models of the internal structure of a specimen. For the study of soil heterogeneity at a wide range of scales, we are focusing on a local glacial deposit. This deposit is a glacial kame terrace of fluvial origin with multi-scale sedimentary structures comprised of unconsolidated sands, clays, and gravels. There are also many joints and faults in the unconsolidated sediments, allowing study of these as potential fluid flow conduits or barriers. We have obtained undisturbed soil samples from this site, allowing detailed laboratory study using similar methods to those described for the sandstone bl

  20. Comparison of Publically Available Methodologies for Development of Geologic Storage Estimates for Carbon Dioxide in Saline Formations

    NASA Astrophysics Data System (ADS)

    Goodman, A.; Strazisar, B. R.; Guthrie, G. D.; Bromhal, G.

    2012-12-01

    High-level estimates of CO2 storage potential at the national, regional, and basin scale are required to assess the potential for carbon capture, utilization, and storage (CCUS) technologies to reduce CO2 emissions for application to saline formations. Both private and public entities worldwide rely on CO2 storage potential estimates for broad energy-related government policy and business decisions. High-level estimates of CO2 geologic storage potential, however, have a high degree of uncertainty because the assessments rely on simplifying assumptions due to the deficiency or absence of data from the subsurface associated with areas of potential storage in saline formations and the natural heterogeneity of geologic formations in general, resulting in undefined rock properties. As site characterization progresses to individual CO2 storage sites, additional site-specific data will likely be collected and analyzed that will allow for the refinement of high-level CO2 storage resource estimates and development of CO2 storage capacities. Until such detailed characterization can be documented, dependable high-level CO2 storage estimates are essential to ensure successful widespread deployment of CCUS technologies. Initiatives for assessing CO2 geologic storage potential have been conducted since 1993. Although dependable high-level CO2 storage estimates are essential to ensure successful deployment of CCUS technologies, it is difficult to assess the uncertainty of these estimates without knowing how the current methodologies targeted at high-level CO2 storage resource estimates for saline formations compare to one another. In this study, we compare high-level CO2 methodologies for development of geologic storage estimates for CO2 in saline formations to assess the uncertainty associated with various methodologies. The methodologies applied are listed as follows: (1) U.S. DOE Methodology: Development of Geologic Storage Potential for Carbon Dioxide at the National and Regional Scale, (2) Carbon Sequestration Leadership Forum: CO2 Storage Capacity Estimation: Methodology and Gaps, (3) U.S. Geologic Survey: A Probabilistic Assessment Methodology for the Evaluation of Geologic Carbon Dioxide Storage, (4) Szulczewski, M., MacMinn, C.W., Herzog, H.J., Juanes, R., 2012 Proc. Natl. Acad. Sci.: Lifetime of carbon capture and storage as a climate-change mitigation technology, and (5) Zhou, Q., Birkholzer, J.T., Tsang, C.-F., Rutqvist, J., 2008 Int. J. of Greenhouse Gas Control 2, 626-639: A method for quick assessment of CO2 storage capacity in closed and semi-closed saline formation. The methodologies are applied to formations throughout the United States.

  1. Approaches to identifying reservoir heterogeneity and reserve growth opportunities from subsurface data: The Oficina Formation, Budare field, Venezuela

    SciTech Connect

    Hamilton, D.S.; Raeuchle, S.K.; Holtz, M.H.

    1997-08-01

    We applied an integrated geologic, geophysical, and engineering approach devised to identify heterogeneities in the subsurface that might lead to reserve growth opportunities in our analysis of the Oficina Formation at Budare field, Venezuela. The approach involves 4 key steps: (1) Determine geologic reservoir architecture; (2) Investigate trends in reservoir fluid flow; (3) Integrate fluid flow trends with reservoir architecture; and (4) Estimate original oil-in-place, residual oil saturation, and remaining mobile oil, to identify opportunities for reserve growth. There are three main oil-producing reservoirs in the Oficina Formation that were deposited in a bed-load fluvial system, an incised valley-fill, and a barrier-strandplain system. Reservoir continuity is complex because, in addition to lateral facies variability, the major Oficina depositional systems were internally subdivided by high-frequency stratigraphic surfaces. These surfaces define times of intermittent lacustrine and marine flooding events that punctuated the fluvial and marginal marine sedimentation, respectively. Syn and post depositional faulting further disrupted reservoir continuity. Trends in fluid flow established from initial fluid levels, response to recompletion workovers, and pressure depletion data demonstrated barriers to lateral and vertical fluid flow caused by a combination of reservoir facies pinchout, flooding shale markers, and the faults. Considerable reserve growth potential exists at Budare field because the reservoir units are highly compartment by the depositional heterogeneity and structural complexity. Numerous reserve growth opportunities were identified in attics updip of existing production, in untapped or incompletely drained compartments, and in field extensions.

  2. Study of heterogeneity loss in upscaling of geological maps by introducing a cluster-based heterogeneity number

    NASA Astrophysics Data System (ADS)

    Ganjeh-Ghazvini, Mostafa; Masihi, Mohsen; Baghalha, Morteza

    2015-10-01

    The prediction of flow behavior in porous media can provide useful insights into the mechanisms involved in CO2 sequestration, petroleum engineering and hydrology. The multi-phase flow is usually simulated by solving the governing equations over an efficient model. The geostatistical (or fine grid) models are rarely used for simulation purposes because they have too many cells. A common approach is to coarsen a fine gird realization by an upscaling method. Although upscaling can speed up the flow simulation, it neglects the fine scale heterogeneity. The heterogeneity loss reduces the accuracy of simulation results. In this paper, the relation between heterogeneity loss during upscaling and accuracy of flow simulation is studied. A realization is divided into some clusters. Every cluster consists of a number of neighboring cells whose permeability values belong to a pre-known interval. The concept of coefficient of variation is applied to define the intra-cluster and inter-cluster heterogeneity numbers. These numbers are then calculated for some fine grid and corresponding upscaled models. The heterogeneous fine grid models are generated by the process of fractional Brownian motion. After simulating water-oil displacement in both fine and coarse models, the relation between flow performance error and heterogeneity loss is investigated. An upper limit for the degree of coarsening is also suggested according to this relation.

  3. Quantification of rock heterogeneities by structural geological field studies combined with laboratory analyses

    NASA Astrophysics Data System (ADS)

    Reyer, Dorothea; Afsar, Filiz; Philipp, Sonja

    2013-04-01

    Heterogeneous rock properties in terms of layering and complex infrastructure of fault zones are typical in sedimentary successions. The knowledge of in-situ mechanical rock properties is crucial for a better understanding of processes such as fracturing and fluid transport in fractured reservoirs. To estimate in situ rock properties at different depths it is important to understand how rocks from outcrops differ from rocks at depth, for example due to alteration and removal of the overburden load. We aim at quantifying these properties by performing structural geological field studies in outcrop analogues combined with laboratory analyses of outcrop samples and drill-cores. The field studies focus on 1) fault zone infrastructure and 2) host rock fracture systems in two different study areas with different lithologies, the North German and the Bristol Channel Basin. We analyse quantitatively the dimension, geometry, persistence and connectivity of fracture systems. The field studies are complemented by systematic sampling to obtain the parameters Young's modulus, compressive and tensile strengths and elastic strain energy (also referred to as destruction work) from which we estimate rock and fracture toughnesses. The results show that in rocks with distinctive layering fractures are often restricted to individual layers, that is, stratabound. The probability of arrest seems to depend on the stiffness contrast between two single layers as well as on the thickness of the softer layer. The results also show that there are clear differences between fault zones in the different lithologies in terms of damage zone thicknesses and fracture system parameters. The results of laboratory analyses show that the mechanical properties vary considerably and for many samples there are clear directional differences. That is, samples taken perpendicular to layering commonly have higher stiffnesses and strengths than those taken parallel to layering. We combine the results of laboratory analyses and field measurements to specify the mechanical heterogeneities of typical sedimentary rocks and of the mechanical units of fault zones. The results from drill-core sample analyses are then compared with the results from the outcrop samples. Another approach is to analyse how rock mechanical properties correlate with petrographic properties (e.g., mineral content, cementation, fabric) to use this knowledge to extrapolate the data to depth. Acknowledgements The authors appreciate the support of 'Niedersächsisches Ministerium für Wissenschaft und Kultur' and 'Baker Hughes' within the gebo research project (http://www.gebo-nds.de). The project "Fracture propagation and reservoir permeability in limestone-marl alternations" is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, http://www.dfg.de).

  4. Geology

    SciTech Connect

    Reidel, Stephen P.

    2008-01-17

    This chapter summarizes the geology of the single-shell tank (SST) farms in the context of the region’s geologic history. This chapter is based on the information in the geology data package for the SST waste management areas and SST RFI Appendix E, which builds upon previous reports on the tank farm geology and Integrated Disposal Facility geology with information available after those reports were published.

  5. The geologic mapping of Venus using C-1 format: Sheets 75N254, 60N263

    NASA Technical Reports Server (NTRS)

    Shalimov, I. V.

    1992-01-01

    The results of geologic mapping of Venus, produced on the base of Magellan images, are presented. We submit two C-1 format geologic maps with the appropriate legend. The mapping territory was taken from Venera 15 and 16 missions and geologic maps were composed. Magellan images allow us to divide some types of the plains units to determine the lava flow direction and to map with better accuracy.

  6. Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic formations

    E-print Network

    Mills, Richard

    Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic performance computing to assess the risks involved in carbon sequestration in deep geologic formations-thermal- chemical processes in variably saturated, non-isothermal porous media is applied to sequestration

  7. Nitrate reduction in geologically heterogeneous catchments--a framework for assessing the scale of predictive capability of hydrological models.

    PubMed

    Refsgaard, Jens Christian; Auken, Esben; Bamberg, Charlotte A; Christensen, Britt S B; Clausen, Thomas; Dalgaard, Esben; Effersø, Flemming; Ernstsen, Vibeke; Gertz, Flemming; Hansen, Anne Lausten; He, Xin; Jacobsen, Brian H; Jensen, Karsten Høgh; Jørgensen, Flemming; Jørgensen, Lisbeth Flindt; Koch, Julian; Nilsson, Bertel; Petersen, Christian; De Schepper, Guillaume; Schamper, Cyril; Sørensen, Kurt I; Therrien, Rene; Thirup, Christian; Viezzoli, Andrea

    2014-01-15

    In order to fulfil the requirements of the EU Water Framework Directive nitrate load from agricultural areas to surface water in Denmark needs to be reduced by about 40%. The regulations imposed until now have been uniform, i.e. the same restrictions for all areas independent of the subsurface conditions. Studies have shown that on a national basis about 2/3 of the nitrate leaching from the root zone is reduced naturally, through denitrification, in the subsurface before reaching the streams. Therefore, it is more cost-effective to identify robust areas, where nitrate leaching through the root zone is reduced in the saturated zone before reaching the streams, and vulnerable areas, where no subsurface reduction takes place, and then only impose regulations/restrictions on the vulnerable areas. Distributed hydrological models can make predictions at grid scale, i.e. at much smaller scale than the entire catchment. However, as distributed models often do not include local scale hydrogeological heterogeneities, they are typically not able to make accurate predictions at scales smaller than they are calibrated. We present a framework for assessing nitrate reduction in the subsurface and for assessing at which spatial scales modelling tools have predictive capabilities. A new instrument has been developed for airborne geophysical measurements, Mini-SkyTEM, dedicated to identifying geological structures and heterogeneities with horizontal and lateral resolutions of 30-50 m and 2m, respectively, in the upper 30 m. The geological heterogeneity and uncertainty are further analysed by use of the geostatistical software TProGS by generating stochastic geological realisations that are soft conditioned against the geophysical data. Finally, the flow paths within the catchment are simulated by use of the MIKE SHE hydrological modelling system for each of the geological models generated by TProGS and the prediction uncertainty is characterised by the variance between the predictions of the different models. PMID:23953482

  8. Estimation of hydrologic properties of heterogeneous geologic media with an inverse method based on iterated function systems

    SciTech Connect

    Doughty, C

    1995-12-01

    The highly heterogeneous nature of most geologic media, coupled with the restricted view of the subsurface available through boreholes, makes it difficult to determine the spatial distribution of subsurface hydrologic properties. Without such a description one cannot predict how fluid flow or solute transport will occur through permeable geologic media, and these predictions are critically needed to address many important environmental problems, including toxic chemical spills, leaking underground storage tanks, and long-term radioactive waste isolation. A common concern of these problems is the possible existence of high-permeability pathways connecting the problem to the biosphere. An understanding of flow and transport behavior is also necessary to optimize energy extraction from petroleum or geothermal reservoirs, where identifying low-permeability barriers that compartmentalize reservoirs and hamper efficient resource utilization is a key problem. The present work describes the development and application of a new inverse method for determining the spatial distribution of hydrologic properties (permeability and specific storage) in heterogeneous geologic media, using pressure transients from interference well tests. The method employs fractal concepts to improve efficiency and reliability. It is applicable to any sort of heterogeneous geologic medium in which wells communicate with each other, whether it be porous, fractured, or a combination thereof. Application to field data from a shallow aquifer at Kesterson Reservoir agrees well with an independent analysis using traditional well-test analysis methods. Application to a series of interference tests conducted at the Gypsy Pilot Site produces a detailed picture of the subsurface, which compares favorably with cross-well seismic imaging studies. 53 refs.

  9. The Effects of Realistic Geological Heterogeneity on Seismic Modeling: Applications in Shear Wave Generation and Near-Surface Tunnel Detection

    NASA Astrophysics Data System (ADS)

    Sherman, Christopher Scott

    Naturally occurring geologic heterogeneity is an important, but often overlooked, aspect of seismic wave propagation. This dissertation presents a strategy for modeling the effects of heterogeneity using a combination of geostatistics and Finite Difference simulation. In the first chapter, I discuss my motivations for studying geologic heterogeneity and seis- mic wave propagation. Models based upon fractal statistics are powerful tools in geophysics for modeling heterogeneity. The important features of these fractal models are illustrated using borehole log data from an oil well and geomorphological observations from a site in Death Valley, California. A large part of the computational work presented in this disserta- tion was completed using the Finite Difference Code E3D. I discuss the Python-based user interface for E3D and the computational strategies for working with heterogeneous models developed over the course of this research. The second chapter explores a phenomenon observed for wave propagation in heteroge- neous media - the generation of unexpected shear wave phases in the near-source region. In spite of their popularity amongst seismic researchers, approximate methods for modeling wave propagation in these media, such as the Born and Rytov methods or Radiative Trans- fer Theory, are incapable of explaining these shear waves. This is primarily due to these method's assumptions regarding the coupling of near-source terms with the heterogeneities and mode conversion. To determine the source of these shear waves, I generate a suite of 3D synthetic heterogeneous fractal geologic models and use E3D to simulate the wave propaga- tion for a vertical point force on the surface of the models. I also present a methodology for calculating the effective source radiation patterns from the models. The numerical results show that, due to a combination of mode conversion and coupling with near-source hetero- geneity, shear wave energy on the order of 10% of the compressional wave energy may be generated within the shear radiation node of the source. Interestingly, in some cases this shear wave may arise as a coherent pulse, which may be used to improve seismic imaging efforts. In the third and fourth chapters, I discuss the results of a numerical analysis and field study of seismic near-surface tunnel detection methods. Detecting unknown tunnels and voids, such as old mine workings or solution cavities in karst terrain, is a challenging prob- lem in geophysics and has implications for geotechnical design, public safety, and domestic security. Over the years, a number of different geophysical methods have been developed to locate these objects (microgravity, resistivity, seismic diffraction, etc.), each with varying results. One of the major challenges facing these methods is understanding the influence of geologic heterogeneity on their results, which makes this problem a natural extension of the modeling work discussed in previous chapters. In the third chapter, I present the results of a numerical study of surface-wave based tunnel detection methods. The results of this analysis show that these methods are capable of detecting a void buried within one wavelength of the surface, with size potentially much less than one wavelength. In addition, seismic surface- wave based detection methods are effective in media with moderate heterogeneity (epsilon < 5 %), and in fact, this heterogeneity may serve to increase the resolution of these methods. In the fourth chapter, I discuss the results of a field study of tunnel detection methods at a site within the Black Diamond Mines Regional Preserve, near Antioch California. I use a com- bination of surface wave backscattering, 1D surface wave attenuation, and 2D attenuation tomography to locate and determine the condition of two tunnels at this site. These results compliment the numerical study in chapter 3 and highlight their usefulness for detecting tunnels at other sites.

  10. Predicting 87Sr/86Sr in surface water using bedrock geology: Understanding geologic heterogeneity and scale to improve isoscapes and animal migration reconstruction

    NASA Astrophysics Data System (ADS)

    Hegg, J. C.; Fremier, A. K.; Kennedy, B. P.

    2012-12-01

    Recent advances in reconstructing location and movement patterns using isotopic tracers have revolutionized the study of migration across taxa. Strontium ratio (87Sr/86Sr) in particular has allowed unprecedented temporal and spatial resolution in migration studies. The development of 87Sr/86Sr isoscapes for surface water has been hindered, however, by the difficulty in predicting 87Sr/86Sr variation across the landscape. The abundance of strontium isotopes is tightly linked to the underlying geology; inviting the possibility that 87Sr/86Sr could be predicted directly from bedrock geology. Accurate predictive models would increase spatial resolution in studies of migration, but previous attempts to predict 87Sr/86Sr in stream water have produced limited success and are not easily generalized across the landscape. Using data from the Snake River of Idaho we present a method for accurately predicting stream water 87Sr/86Sr from bedrock. We further show that our predictions can be used to accurately determine the origin of fish based upon the distinct 87Sr/86Sr signatures in their otoliths. We discuss the importance of understanding the affects of geologic heterogeneity and scale for improving our ability to generalize predictions in future models.

  11. Numerical study on the impacts of heterogeneous reactions on ozone formation in the Beijing urban area

    NASA Astrophysics Data System (ADS)

    Xu, Jun; Zhang, Yuanhang; Wang, Wei

    2006-12-01

    The air quality model CMAQ-MADRID (Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution) was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO?NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations.

  12. Fundamental Study on the Dynamics of Heterogeneity-Enhanced CO2 Gas Evolution in the Shallow Subsurface During Possible Leakage from Deep Geologic Storage Sites

    NASA Astrophysics Data System (ADS)

    Plampin, M. R.; Lassen, R. N.; Sakaki, T.; Pawar, R.; Jensen, K.; Illangasekare, T. H.

    2013-12-01

    A concern for geologic carbon sequestration is the potential for CO2 stored in deep geologic formations to leak upward into shallow freshwater aquifers where it can have potentially detrimental impacts to the environment and human health. Understanding the mechanisms of CO2 exsolution, migration and accumulation (collectively referred to as 'gas evolution') in the shallow subsurface is critical to predict and mitigate the environmental impacts. During leakage, CO2 can move either as free-phase or as a dissolved component of formation brine. CO2 dissolved in brine may travel upward into shallow freshwater systems, and the gas may be released from solution. In the shallow aquifer, the exsolved gas may accumulate near interfaces between soil types, and/or create flow paths that allow the gas to escape through the vadose zone to the atmosphere. The process of gas evolution in the shallow subsurface is controlled by various factors, including temperature, dissolved CO2 concentration, water pressure, background water flow rate, and geologic heterogeneity. However, the conditions under which heterogeneity controls gas phase evolution have not yet been precisely defined and can therefore not yet be incorporated into models used for environmental risk assessment. The primary goal of this study is to conduct controlled laboratory experiments to help fill this knowledge gap. With this as a goal, a series of intermediate-scale laboratory experiments were conducted to observe CO2 gas evolution in porous media at multiple scales. Deionized water was saturated with dissolved CO2 gas under a specified pressure (the saturation pressure) before being injected at a constant volumetric flow rate into the bottom of a 1.7 meter-tall by 5.7 centimeter-diameter column or a 2.4 meter-tall by 40 centimeter-wide column that were both filled with sand in various heterogeneous packing configurations. Both test systems were initially saturated with fresh water and instrumented with soil moisture sensors to monitor the evolution of gas phase through time by measuring the average water content in small sampling volumes of soil. Tensiometers allowed for observation of water pressure through space and time in the test systems, and a computer-interfaced electronic scale continuously monitored the outflow of water from the top of the two test columns. Several packing configurations with five different types of sands were used in order to test the effects of various pore size contrasts and interface shapes on the evolution of the gas phase near soil texture transitions in the heterogeneous packings. Results indicate that: (1) heterogeneity affects gas phase evolution patterns within a predictable range of conditions quantified by the newly introduced term 'oversaturation,' (2) soil transition interfaces where less permeable material overlies more permeable material have a much more pronounced effect on gas evolution than interfaces with opposite orientations, and (3) anticlines (or stratigraphic traps) cause significantly greater gas accumulation than horizontal interfaces. Further work is underway to apply these findings to more realistic, two-dimensional scenarios, and to assess how well existing numerical models can capture these processes.

  13. Heterogeneous Reservoir Characterization Utilizing Efficient Geology Preserving Reservoir Parameterization through Higher Order Singular Value Decomposition (HOSVD) 

    E-print Network

    Afra, Sardar

    2015-01-21

    , the process of estimating a large number of unknowns in an inverse problem lead to a very costly computational effort. Moreover, it is very important to perform geologically consistent reservoir parameter adjustments as data is being assimilated in the history...

  14. Bacterial interactions and transport in geological formation of alumino-silica clays.

    PubMed

    Vu, Kien; Yang, Guang; Wang, Boya; Tawfiq, Kamal; Chen, Gang

    2015-01-01

    Bacterial transport in the subsurface is controlled by their interactions with the surrounding environment, which are determined by the surface properties of the geological formation and bacterial surfaces. In this research, surface thermodynamic properties of Escherichia coli and the geological formation of alumino-silica clays were characterized based on contact angle measurements, which were utilized to quantify the distance-dependent interactions between E. coli and the geological formation according to the traditional and extended Derjaguin, Landau, Verwey and Overbeek (DLVO) theory. E. coli attachment to alumino-silica clays was evaluated in laboratory columns under saturated and steady-state flow conditions. E. coli deposition coefficient and desorption coefficient were simulated using convection-dispersion transport models against E. coli breakthrough curves, which were then linked to interactions between E. coli and the geological formation. It was discovered that E. coli deposition was controlled by the long-ranged electrostatic interaction and E. coli desorption was attributed to the short-ranged Lifshitz-van der Waals and Lewis acid-base interactions. E. coli transport in three layers of different alumino-silica clays was further examined and the breakthrough curve was simulated using E. coli deposition coefficient and desorption coefficient obtained from their individual column experiments. The well-fitted simulation confirmed that E. coli transport observations were interaction-dependent phenomena between E. coli and the geological formation. PMID:25437062

  15. A Standard-Driven Data Dictionary for Data Harmonization of Heterogeneous Datasets in Urban Geological Information Systems

    NASA Astrophysics Data System (ADS)

    Liu, G.; Wu, C.; Li, X.; Song, P.

    2013-12-01

    The 3D urban geological information system has been a major part of the national urban geological survey project of China Geological Survey in recent years. Large amount of multi-source and multi-subject data are to be stored in the urban geological databases. There are various models and vocabularies drafted and applied by industrial companies in urban geological data. The issues such as duplicate and ambiguous definition of terms and different coding structure increase the difficulty of information sharing and data integration. To solve this problem, we proposed a national standard-driven information classification and coding method to effectively store and integrate urban geological data, and we applied the data dictionary technology to achieve structural and standard data storage. The overall purpose of this work is to set up a common data platform to provide information sharing service. Research progresses are as follows: (1) A unified classification and coding method for multi-source data based on national standards. Underlying national standards include GB 9649-88 for geology and GB/T 13923-2006 for geography. Current industrial models are compared with national standards to build a mapping table. The attributes of various urban geological data entity models are reduced to several categories according to their application phases and domains. Then a logical data model is set up as a standard format to design data file structures for a relational database. (2) A multi-level data dictionary for data standardization constraint. Three levels of data dictionary are designed: model data dictionary is used to manage system database files and enhance maintenance of the whole database system; attribute dictionary organizes fields used in database tables; term and code dictionary is applied to provide a standard for urban information system by adopting appropriate classification and coding methods; comprehensive data dictionary manages system operation and security. (3) An extension to system data management function based on data dictionary. Data item constraint input function is making use of the standard term and code dictionary to get standard input result. Attribute dictionary organizes all the fields of an urban geological information database to ensure the consistency of term use for fields. Model dictionary is used to generate a database operation interface automatically with standard semantic content via term and code dictionary. The above method and technology have been applied to the construction of Fuzhou Urban Geological Information System, South-East China with satisfactory results.

  16. On stochastic modeling of flow in multimodal heterogeneous formations

    NASA Astrophysics Data System (ADS)

    Lu, Zhiming; Zhang, Dongxiao

    2002-10-01

    Most existing stochastic models are developed for unimodal porous media that may be well characterized with only the first two statistical moments. However, the distribution of hydraulic properties, such as hydraulic conductivity, may possess a multiplicity of modes; thus the first two moments may not be adequate to characterize properties of such porous media. In turn, the stochastic models developed for unimodal porous media may not be applicable to flow and transport in a multimodal heterogeneous porous medium. This study investigates under what circumstances the second-order moment-based stochastic models are applicable to multimodal heterogeneous porous media. We assume that a porous medium is composed of a number of materials (categories), each of which may have a different mean, variance, and correlation scale. The distribution of materials in the domain is characterized by indicator random variables. We first derive analytical expressions for the mean and covariance of the log saturated hydraulic conductivity (ln Ks) of the multimodal porous medium in terms of categorical proportions, transition probability among categories, and covariances of indicator random variables. We express the covariance in terms of the statistics of materials in the porous medium, which allows us to accurately evaluate the variance and the correlation length of the composite ln Ks field. We then solve the second-order moment equations for the "equivalent" unimodal field with an exponential covariance with a single correlation scale computed for the composite field. On the other hand, we conduct two sets of Monte Carlo simulations: one with multimodal random fields, and the other with "equivalent" unimodal random fields. Examples for porous media with two materials are given. Numerical experiments show that a bimodal ln Ks field may be well approximated by an equivalent unimodal field when one of the two modes is dominant, under which condition the applicability of the second-order moment-based model is subject to the same limitation of relatively small variance as that for unimodal fields. When the bimodal distribution has two more or less equally important modes, although it cannot be adequately represented by an equivalent unimodal distribution, the second-order moment-based stochastic model seems to be applicable to systems with larger composite variances than it does for an one-mode-dominant distribution.

  17. Formation Buffering Potential Pertaining to Geological Storage of Carbon Dioxide

    NASA Astrophysics Data System (ADS)

    Ellis, B. R.; Peters, C. A.; Buschkuehle, M.

    2007-12-01

    One promising strategy for decreasing CO2 emissions to the atmosphere is carbon capture and storage in deep saline formations. Modeling efforts and the experimental measurements that support these efforts are critical to determining the fate of injected CO2. The focus of this work is CO2-water-rock interactions as they pertain to formation buffering potential. PHREEQC was used to model pH evolution in siliciclastic and carbonate rocks after simulated injection of CO2. The initial mineral and formation water compositions were determined from analysis of core samples and brines from several formations in the Alberta sedimentary basin in western Canada. Simulation parameters correspond to injection conditions of 50°C, CO2 pressure of 100 bar and high ionic strength. Results indicate that the carbonate formations have a higher buffering potential relative to siliciclastic formations. Considerable variability of acid-catalyzed reactions among formations with similar mineralogical compositions was also observed. To assess the effect of grain coating by clay minerals, a comparative simulation was performed with kaolinite as the dominant mineral in contact with the pore fluids. Results from this simulation showed a pronounced retardation in pH buffering reaction kinetics. This emphasizes the importance for differentiating between mineral abundance and accessibility in model calculations when clay coatings may obscure contact between pore fluids and potentially reactive minerals.

  18. River-aquifer interactions, geologic heterogeneity, and low-flow management

    USGS Publications Warehouse

    Fleckenstein, J.H.; Niswonger, R.G.; Fogg, G.E.

    2006-01-01

    Low river flows are commonly controlled by river-aquifer exchange, the magnitude of which is governed by hydraulic properties of both aquifer and aquitard materials beneath the river. Low flows are often important ecologically. Numerical simulations were used to assess how textural heterogeneity of an alluvial system influences river seepage and low flows. The Cosumnes River in California was used as a test case. Declining fall flows in the Cosumnes River have threatened Chinook salmon runs. A ground water-surface water model for the lower river basin was developed, which incorporates detailed geostatistical simulations of aquifer heterogeneity. Six different realizations of heterogeneity and a homogenous model were run for a 3-year period. Net annual seepage from the river was found to be similar among the models. However, spatial distribution of seepage along the channel, water table configuration and the level of local connection, and disconnection between the river and aquifer showed strong variations among the different heterogeneous models. Most importantly, the heterogeneous models suggest that river seepage losses can be reduced by local reconnections, even when the regional water table remains well below the riverbed. The percentage of river channel responsible for 50% of total river seepage ranged from 10% to 26% in the heterogeneous models as opposed to 23% in the homogeneous model. Differences in seepage between the models resulted in up to 13 d difference in the number of days the river was open for salmon migration during the critical fall months in one given year. Copyright ?? 2006 The Author(s).

  19. CO2 leakage risk in 3D heterogeneous formations

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    In this study we use a stochastic sensitivity analysis framework to evaluate the impact of 3D 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/factors in the form of prior pdfs (probability density functions). Effective sampling of the prior pdfs enables us to explore the parameter space and systematically evaluate the individual and combined effects of the factors/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 (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, a scalable version simulator, eSTOMP, is run on the Jaguar supercomputer. We then perform statistical analyses and summarize the relationships between the parameters of interest (mean/variance/anisotropy ratio of caprock/reservoir permeability) and CO2 leakage ratio. We will also present the effects of those parameters on CO2 plume radius and reservoir injectivity.

  20. On the use of block-effective macrodispersion for numerical simulations of transport in heterogeneous formations

    E-print Network

    Rubin, Yoram

    . In doing that, we wish to preserve the interplay between all relevant length scales: those relevant for numerical simulations of transport in heterogeneous formations, Water Resour. Res., 39(9), 1242, doi:10 by way of advection and disper- sion. The effect of these length scales on transport can be conveniently

  1. HETEROGENEOUS NOX CHEMISTRY IN POLLUTED URBAN ATMOSPHERES: IMPLICATIONS FOR THE FORMATION OF PARTICLES AND OZONE AND

    E-print Network

    Dabdub, Donald

    HETEROGENEOUS NOX CHEMISTRY IN POLLUTED URBAN ATMOSPHERES: IMPLICATIONS FOR THE FORMATION OF PARTICLES AND OZONE AND CONTROL STRATEGY DEVELOPMENT Final Report Contract No. 00-323 Prepared for: California Air Resources Board and the California Environmental Protection Agency Research Division P.O. Box

  2. Modeling Heterogeneous CINO2 Formation, Chloride Availability, and Chlorine Cycling in Southeast Texas

    EPA Science Inventory

    Nitryl chloride (ClNO2) mixing ratios above 1 ppbv have been measured off the coast of Southeast Texas. ClNO2 formation, the result of heterogeneous N205 uptake on chloride-containing aerosols, has a significant impact on oxidant form...

  3. Use and Features of Basalt Formations for Geologic Sequestration

    SciTech Connect

    McGrail, B. Peter; Ho, Anita M.; Reidel, Steve P.; Schaef, Herbert T.

    2003-01-01

    Extrusive lava flows of basalt are a potential host medium for geologic sequestration of anthropogenic CO2. Flood basalts and other large igneous provinces occur worldwide near population and power-producing centers and could securely sequester a significant fraction of global CO2 emissions. We describe the location, extent, and general physical and chemical characteristics of large igneous provinces that satisfy requirements as a good host medium for CO2 sequestration. Most lava flows have vesicular flow tops and bottoms as well as interflow zones that are porous and permeable and serve as regional aquifers. Additionally, basalt is iron-rich, and, under the proper conditions of groundwater pH, temperature, and pressure, injected CO2 will react with iron released from dissolution of primary minerals in the basalt to form stable ferrous carbonate minerals. Conversion of CO2 gas into a solid form was confirmed in laboratory experiments with supercritical CO2 in contact with basalt samples from Washington state.

  4. Permafrost on Mars: distribution, formation, and geological role

    NASA Technical Reports Server (NTRS)

    Nummedal, D.

    1984-01-01

    The morphology of channels, valleys, chaotic and fretted terrains and many smaller features on Mars is consistent with the hypothesis that localized deterioration of thick layers of ice-rich permafrost was a dominant geologic process on the Martian surface. Such ground ice deterioration gave rise to large-scale mass movement, including sliding, slumping and sediment gravity flowage, perhaps also catastropic floods. In contrast to Earth, such mass movement processes on Mars lack effective competition from erosion by surface runoff. Therefore, Martian features due to mass movement grew to reach immense size without being greatly modified by secondary erosional processes. The Viking Mission to Mars in 1976 provided adequate measurements of the relevant physical parameters to constrain models for Martian permafrost.

  5. Comparison of methods for geologic storage of carbon dioxide in saline formations

    SciTech Connect

    Goodman, Angela L.; Bromhal, Grant S.; Strazisar, Brian; Rodosta, Traci D.; Guthrie, William J.; Allen, Douglas E.; Guthrie, George D.

    2013-01-01

    Preliminary estimates of CO{sub 2} storage potential in geologic formations provide critical information related to Carbon Capture, Utilization, and Storage (CCUS) technologies to mitigate CO{sub 2} emissions. Currently multiple methods to estimate CO{sub 2} storage and multiple storage estimates for saline formations have been published, leading to potential uncertainty when comparing estimates from different studies. In this work, carbon dioxide storage estimates are compared by applying several commonly used methods to general saline formation data sets to assess the impact that the choice of method has on the results. Specifically, six CO{sub 2} storage methods were applied to thirteen saline formation data sets which were based on formations across the United States with adaptations to provide the geologic inputs required by each method. Methods applied include those by (1) international efforts – the Carbon Sequestration Leadership Forum (Bachu et al., 2007); (2) United States government agencies – U.S. Department of Energy – National Energy Technology Laboratory (US-DOE-NETL, 2012) and United States Geological Survey (Brennan et al., 2010); and (3) the peer-reviewed scientific community – Szulczewski et al. (2012) and Zhou et al. (2008). A statistical analysis of the estimates generated by multiple methods revealed that assessments of CO{sub 2} storage potential made at the prospective level were often statistically indistinguishable from each other, implying that the differences in methodologies are small with respect to the uncertainties in the geologic properties of storage rock in the absence of detailed site-specific characterization.

  6. A Highly Efficient Heterogenized Iridium Complex for the Catalytic Hydrogenation of Carbon Dioxide to Formate.

    PubMed

    Park, Kwangho; Gunasekar, Gunniya Hariyanandam; Prakash, Natarajan; Jung, Kwang-Deog; Yoon, Sungho

    2015-10-01

    A heterogenized catalyst on a highly porous covalent triazine framework was synthesized and characterized to have a coordination environment similar to that of its homogeneous counterpart. The catalyst efficiently converted CO2 into formate through hydrogenation with a turnover number of 5000 after 2?h and an initial turnover frequency of up to 5300?h(-1) ; both of these values are the highest reported to date for a heterogeneous catalyst, which makes it attractive toward industrial application. Furthermore, the synthesized catalyst was found to be stable in air and was recycled by simple filtration without significant loss of catalytic activity. PMID:26493515

  7. Approaches to large scale unsaturated flow in heterogeneous, stratified, and fractured geologic media

    SciTech Connect

    Ababou, R.

    1991-08-01

    This report develops a broad review and assessment of quantitative modeling approaches and data requirements for large-scale subsurface flow in radioactive waste geologic repository. The data review includes discussions of controlled field experiments, existing contamination sites, and site-specific hydrogeologic conditions at Yucca Mountain. Local-scale constitutive models for the unsaturated hydrodynamic properties of geologic media are analyzed, with particular emphasis on the effect of structural characteristics of the medium. The report further reviews and analyzes large-scale hydrogeologic spatial variability from aquifer data, unsaturated soil data, and fracture network data gathered from the literature. Finally, various modeling strategies toward large-scale flow simulations are assessed, including direct high-resolution simulation, and coarse-scale simulation based on auxiliary hydrodynamic models such as single equivalent continuum and dual-porosity continuum. The roles of anisotropy, fracturing, and broad-band spatial variability are emphasized. 252 refs.

  8. GEOLOGICAL CONTROLS IN THE FORMATIONS AND EXPANSIONS OF GULLIES OVER HILLSLOPE HYDROLOGICAL PROCESSES IN THE

    E-print Network

    GEOLOGICAL CONTROLS IN THE FORMATIONS AND EXPANSIONS OF GULLIES OVER HILLSLOPE HYDROLOGICAL with several local structures and intrusive dykes. Volcanic morphological features and erosion has formed of gullies along hill slopes in a micro watershed in the Blue Nile River source region. Twenty

  9. Stratigraphy, structural geology and metamorphism of the Inwood Marble Formation, northern Manhattan, NYC, NY

    E-print Network

    Merguerian, Charles

    Stratigraphy, structural geology and metamorphism of the Inwood Marble Formation, northern, Hofstra University, Hempstead, NY 11549 Introduction Field studies of the Inwood Marble in the type of recrystallized dolomite and subordinate calcite marble the Inwood Marble was used for quarrying and mineral

  10. Geology and hydrogeology of the Dammam Formation in Kuwait

    NASA Astrophysics Data System (ADS)

    Al-Awadi, E.; Mukhopadhyay, A.; Al-Senafy, M. N.

    The Dammam Formation of Middle Eocene age is one of the major aquifers containing useable brackish water in Kuwait. Apart from the paleokarst zone at the top, the Dammam Formation in Kuwait consists of 150-200m of dolomitized limestone that is subdivided into three members, on the basis of lithology and biofacies. The upper member consists of friable chalky dolomicrite and dolomite. The middle member is mainly laminated biomicrite and biodolomicrite. The lower member is nummulitic limestone with interlayered shale toward the base. Geophysical markers conform to these subdivisions. Core analyses indicate that the upper member is the most porous and permeable of the three units, as confirmed by the distribution of lost-circulation zones. The quality of water in the aquifer deteriorates toward the north and east. A potentiometric-head difference exists between the Dammam Formation and the unconformably overlying Kuwait Group; this difference is maintained by the presence of an intervening aquitard. Résumé La formation de Damman, d'âge Éocène moyen, est l'un des principaux aquifères du Koweit, contenant de l'eau saumâtre utilisable. A part dans sa partie supérieure où existe un paléokarst, la formation de Damman au Koweit est constituée par 150 à 200m de calcaires dolomitisés, divisés en trois unités sur la base de leur lithologie et de biofaciès. L'unité supérieure est formée d'une dolomicrite crayeuse et friable et d'une dolomie. L'unité médiane est pour l'essentiel une biomicrite laminée et une biodolomicrite. L'unité inférieure est un calcaire nummulitique avec des intercalations argileuses vers la base. Les marqueurs géophysiques sont conformes à ces subdivisions. Les analyses de carottes montrent que l'unité supérieure est la plus poreuse et la plus perméable des trois. La répartition des zones d'écoulement souterrain confirment ces données. La qualité de l'eau dans l'aquifère se dégrade en direction du nord et de l'est. Une différence de niveau piézométrique est observée entre la formation de Damman et le groupe de Koweit qui la recouvre en discordance; cette différence est due à la présence d'un niveau imperméable qui la maintient captive. Resumen La Formación Damman, del Eoceno Medio, es uno de los mayores acuíferos de agua salobre aprovechable en Kuwait. Además de una zona de paleokarst en la parte superior, la Formación Damman en Kuwait consiste en 150-200m de caliza dolomitizada, que se subdivide en tres zonas en función de la litología y la biofacies. La parte superior está formada por dolomicrita yesífera friable y dolomita. La parte central es básicamente biomicrita laminada y biodolomicrita. La inferior es caliza nummulítica, con intercalaciones de pizarra en la base. Los marcadores geofísicos reflejan claramente estas subdivisiones. Los análisis de testigos revelan que la parte superior es la más porosa y permeable de las tres unidades. Esto queda confirmado con la distribución de zonas de circulación perdidas. La calidad del agua en el acuífero se deteriora hacia el norte y el este. Sobre la Formación Damman, y de manera no conforme, suprayace otra formación, que se conoce como Grupo Kuwaití. Existe una diferencia de niveles piezométricos entre ambas formaciones, la cual se mantiene por la presencia de una capa semiconfinante.

  11. Thermal state and complex geology of a heterogeneous salty crust of Jupiter's satellite, Europa

    USGS Publications Warehouse

    Prieto-Ballesteros, O.; Kargel, J.S.

    2005-01-01

    The complex geology of Europa is evidenced by many tectonic and cryomagmatic resurfacing structures, some of which are "painted" into a more visible expression by exogenic alteration processes acting on the principal endogenic cryopetrology. The surface materials emplaced and affected by this activity are mainly composed of water ice in some areas, but in other places there are other minerals involved. Non-ice minerals are visually recognized by their low albedo and reddish color either when first emplaced or, more likely, after alteration by Europan weathering processes, especially sublimation and alteration by ionizing radiation. While red chromophoric material could be due to endogenic production of solid sulfur allotropes or other compounds, most likely the red substance is an impurity produced by radiation alteration of hydrated sulfate salts or sulphuric acid of mainly internal origin. If the non-ice red materials or their precursors have a source in the satellite interior, and if they are not merely trace contaminants, then they can play an important role in the evolution of the icy crust, including structural differentiation and the internal dynamics. Here we assume that these substances are major components of Europa's cryo/hydrosphere, as some models have predicted they should be. If this is an accurate assumption, then these substances should not be neglected in physical, chemical, and biological models of Europa, even if major uncertainties remain as to the exact identity, abundance, and distribution of the non-ice materials. The physical chemical properties of the ice-associated materials will contribute to the physical state of the crust today and in the geological past. In order to model the influence of them on the thermal state and the geology, we have determined the thermal properties of the hydrated salts. Our new lab data reveal very low thermal conductivities for hydrated salts compared to water ice. Lower conductivities of salty ice would produce steeper thermal gradients than in pure ice. If there are salt-rich layers inside the crust, forming salt beds over the seafloor or a briny eutectic crust, for instance, the high thermal gradients may promote endogenic geological activity. On the seafloor, bedded salt accumulations may exhibit high thermochemical gradients. Metamorphic and magmatic processes and possible niches for thermophilic life at shallow suboceanic depths result from the calculated thermal profiles, even if the ocean is very cold. ?? 2004 Elsevier Inc. All rights reserved.

  12. Prediction of terrestrial gamma dose rate based on geological formations and soil types in the Johor State, Malaysia.

    PubMed

    Saleh, Muneer Aziz; Ramli, Ahmad Termizi; bin Hamzah, Khaidzir; Alajerami, Yasser; Moharib, Mohammed; Saeed, Ismael

    2015-10-01

    This study aims to predict and estimate unmeasured terrestrial gamma dose rate (TGDR) using statistical analysis methods to derive a model from the actual measurement based on geological formation and soil type. The measurements of TGDR were conducted in the state of Johor with a total of 3873 measured points which covered all geological formations, soil types and districts. The measurements were taken 1 m above the soil surface using NaI [Ti] detector. The measured gamma dose rates ranged from 9 nGy h(-1) to 1237 nGy h(-1) with a mean value of 151 nGy h(-1). The data have been normalized to fit a normal distribution. Tests of significance were conducted among all geological formations and soil types, using the unbalanced one way ANOVA. The results indicated strong significant differences due to the different geological formations and soil types present in Johor State. Pearson Correlation was used to measure the relations between gamma dose rate based on geological formation and soil type (D(G,S)) with the gamma dose rate based on geological formation (D(G)) or soil type (D(s)). A very good correlation was found between D(G,S) and D(G) or D(G,S) and D(s). A total of 118 pairs of geological formations and soil types were used to derive the statistical contribution of geological formations and soil types to gamma dose rates. The contribution of the gamma dose rate from geological formation and soil type were found to be 0.594 and 0.399, respectively. The null hypotheses were accepted for 83% of examined data, therefore, the model could be used to predict gamma dose rates based on geological formation and soil type information. PMID:26142818

  13. Geological conditions of the time of formation of impact craters on Pai-Khoi

    NASA Astrophysics Data System (ADS)

    Mashchak, M. S.

    Present-day ideas on the time of formation of the Kara and Ust-Kara astroblemes are presented, and the main features of the geological structure of Phai-Khoi (the region where these structures are located) are described. Based on an analysis of the geological conditions, a large complex of fossil fauna and diatomaceous algae, and radiological dating of tagamites and impact glasses, it is shown that the craters were formed on the Cretaceous-Paleogene boundary about 66-67 million years ago.

  14. Geological study of uranium potential of the Kingston Peak Formation, Death Valley Region, California

    SciTech Connect

    Carlisle, D.; Kettler, R.M.; Swanson, S.C.

    1980-09-01

    The results of a geological survey of the Kingston Peak Formation on the western slope of the Panamint Range near Death Valley are discussed. The geology of the Panamint mountains was mapped on topographic base maps of the Telescope Peak and Manly Peak quadrangles. Radiometric suveys of the area were conducted using gamma ray spectrometers. Samples of the conglomerate were analyzed using delayed neutron, neutron activation, atomic absorption, and LECO analysis. It is concluded that uranium mineralization in the Favorable Submember is significant and further exploration is warranted. The monazite-fenotime related uranium and thorium mineralization in the Mountain Girl quartz pebble conglomerate is of no economic interest. (DMC)

  15. Geologic Observations and Numerical Modeling: A Combined Approach to Understanding Crater and Basin Formation and Structure

    NASA Astrophysics Data System (ADS)

    Potter, R. W. K.; Head, J. W., III

    2014-12-01

    Impact cratering is a fundamental geological process throughout the Solar System. The Moon is an ideal location to document the impact cratering process due to the number and excellent state of preservation of large craters and basins, and the wide range of geological, geophysical, topographic, mineralogic, remote sensing and returned sample data. Despite the number and excellent preservation state of many large complex craters and basins, their formation and the origin of their structural features and the stages in their evolution remain contentious. To more comprehensively document the final stage of lunar impact basin formation, we have compiled detailed topographic, geological and mineralogic maps of several type examples of peak-ring and multi-ring basins, including the Orientale basin. These data include the mineralogic characteristics of basin ring structures and assist in the interpretation of the target stratigraphy, and the depth of origin of basin rings. Data for the current structure of basins is compared to numerical model outputs of basin-forming impacts, which track formation to the conclusion of dynamic processes (2 to 3 hours after impact). We use the Orientale basin as an example and provide combined correlations and interpretations that assign rings to various stages in the numerical models, and compare these candidates to crustal stratigraphy, with the ultimate aim of producing a consistent model for large crater/basin formation. The shock physics code iSALE is used to numerically model the basin-scale impacts. Constitutive equations and equations of state for materials analogous to the lunar crust (gabbroic anorthosite) and mantle (dunite) are used. Aspects of the numerically-produced lunar basins (e.g., material distribution and accumulated stress) are compared and contrasted to remote observations and geological maps of the Orientale rings and geological units, including ejecta and impact melt deposits.

  16. Investigations of emissions and heterogeneous formation of HONO in a road traffic tunnel

    NASA Astrophysics Data System (ADS)

    Kurtenbach, R.; Becker, K. H.; Gomes, J. A. G.; Kleffmann, J.; Lörzer, J. C.; Spittler, M.; Wiesen, P.; Ackermann, R.; Geyer, A.; Platt, U.

    Simultaneous measurements of nitrous acid (HONO) and nitrogen dioxide (NO 2) using a differential optical absorption spectroscopy system, nitrogen oxide (NO) by an in situ chemiluminescence analyser and carbon dioxide (CO 2) by a gas chromatographic technique were carried out in the Wuppertal Kiesbergtunnel. At high traffic density HONO concentrations of up to 45 ppbV were observed. However, at low traffic density unexpectedly high HONO concentrations of up to 10 ppbV were measured caused by heterogeneous HONO formation on the tunnel walls. In addition to the tunnel campaigns, emission measurements of HONO, NO 2, NO and CO 2 from different single vehicles (a truck, a diesel and a gasoline passenger car) were also performed. For the correction of the HONO emission data, the heterogeneous HONO formation on the tunnel walls was quantified by two different approaches (a) in different NO 2 emission experiments in the tunnel without traffic and (b) on tunnel wall residue in the laboratory. The HONO concentration corrected for heterogeneous formation on the tunnel walls, in relation to the CO 2 concentration can be used to estimate the amount of HONO, which is directly emitted from the vehicle fleet. From the measured data, emission ratios (e.g. HONO/NO x) and emission indices (e.g. mg HONO kg -1 fuel) were calculated. The calculated emission index of 88±18 mg HONO kg -1 fuel allows an estimation of the HONO emission rates from traffic into the atmosphere. Furthermore, the heterogeneous formation of HONO from NO 2 on freshly emitted exhaust particles is discussed.

  17. Risk Assessment of Geologic Formation Sequestration in The Rocky Mountain Region, USA

    SciTech Connect

    Lee, Si-Yong; McPherson, Brian

    2013-08-01

    The purpose of this report is to describe the outcome of a targeted risk assessment of a candidate geologic sequestration site in the Rocky Mountain region of the USA. Specifically, a major goal of the probabilistic risk assessment was to quantify the possible spatiotemporal responses for Area of Review (AoR) and injection-induced pressure buildup associated with carbon dioxide (CO?) injection into the subsurface. Because of the computational expense of a conventional Monte Carlo approach, especially given the likely uncertainties in model parameters, we applied a response surface method for probabilistic risk assessment of geologic CO? storage in the Permo-Penn Weber formation at a potential CCS site in Craig, Colorado. A site-specific aquifer model was built for the numerical simulation based on a regional geologic model.

  18. Color heterogeneity of the surface of Phobos: Relationships to geologic features and comparison to meteorite analogs

    SciTech Connect

    Murchie, S.L.; Britt, D.T.; Head, J.W.; Pratt, S.F.; Fisher, P.C. ); Zhukov, B.S.; Kuzmin, A.A.; Ksanfomality, L.V.; Zharkov, A.V.; Nikitin, G.E. ); Fanale, F.P.; Blaney, D.L.; Bell, J.F.; Robinson, M.S. )

    1991-04-10

    Multispectral observations of Phobos by the VSK (Videospectrometric) TV cameras and KRFM (Combined Radiometer and Photometer for Mars) UV-visible spectrometer on Phobos 2 have provided new determinations of the satellite's spectral reflectance properties, at greater spatial and spectral resolutions and over a greater geographic range than have previously been available. Images of the ratio of visible and NIR reflectances covering the longitude range 30-250{degrees}W were constructed from 0.40-0.56 {mu}m and 0.78-1.1 {mu}m VSK images. The average color ratio of Phobos was found to be {approximately}0.97{plus minus}0.14, consistent with previously obtained measurements. However, the surface is heterogeneous, with at least four recognizable spectral units whose absolute color ratios were determined to within {approximately}10%: a red unit with a color ratio of 0.7-0.8, a reddish gray unit with a color ratio of 0.8-1.0, a bluish gray unit with a color ratio of 1.0-1.1, and a blue unit with a color ratio of 1.1-1.4. The redder and bluer color units are interpreted to have been excavated by impacts, from an optically and/or compositionally heterogeneous interior overlain by a reddish gray surficial layer. The location of the blue lobe emanating from Stickney correlates with the location of one of the morphologic classes of grooves, as predicted by ejecta reimpact models of groove origin. The large color ratio of blue material is comparable to that of an assemblage of mafic minerals like that forming black chondrites. Qualitative and quantitative comparison of the color ratio and UV-visible spectral properties of bluish gray material with those of meteorites indicates that black chondrites are this material's closest spectral analog. The UV-visible spectra of reddish gray and red materials most resemble spectra of black chondrites but are also comparable to spectra of some carbonaceous chondrites.

  19. Methods and apparatus for measurement of electronic properties of geological formations through borehole casing

    DOEpatents

    Vail, III, William B. (Bothell, WA)

    1989-01-01

    Methods and apparatus are provided for measuring electronic properties of geological formations and cement layers adjacent to cased boreholes including resistivities, polarization phenomena and dielectric constants. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. At least three voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of differential current conducted into formation in the vicinity of those electrodes. These measurements facilitate calculation of the resistivities of the adjacent geological formations as well as an indication of whether cement is present. Measurements of the differential voltage response to transient currents provide a measurement of the polarization phenomena in formation as well as the capacitance of the casing in contact with the formation which is useful for determining whether oil and gas are present. Lithological characteristics of the formation such as the presence or absence of clay can also be determined. A calibration procedure is provided for minimizing errors induced by variations in the casing. The device also may be placed within the pipe attached to a drill bit while drilling open holes.

  20. Methods and apparatus for measurement of electronic properties of geological formations through borehole casing

    DOEpatents

    Vail, W.B. III.

    1989-11-21

    Methods and apparatus are provided for measuring electronic properties of geological formations and cement layers adjacent to cased boreholes including resistivities, polarization phenomena and dielectric constants. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. At least three voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of differential current conducted into formation in the vicinity of those electrodes. These measurements facilitate calculation of the resistivities of the adjacent geological formations as well as an indication of whether cement is present. Measurements of the differential voltage response to transient currents provide a measurement of the polarization phenomena in formation as well as the capacitance of the casing in contact with the formation which is useful for determining whether oil and gas are present. Lithological characteristics of the formation such as the presence or absence of clay can also be determined. A calibration procedure is provided for minimizing errors induced by variations in the casing. The device also may be placed within the pipe attached to a drill bit while drilling open holes. 48 figs.

  1. Methods and apparatus for measurement of electronic properties of geological formations through borehole casing

    DOEpatents

    Vail, W.B. III.

    1991-08-27

    Methods and apparatus are provided for measuring electronic properties of geological formations and cement layers adjacent to cased boreholes including resistivities, polarization phenomena and dielectric constants. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. At least three voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the differential current conducted into the formation in the vicinity of those electrodes. These measurements facilitate calculation of the resistivities of the adjacent geological formations as well as an indication of whether cement is present. Measurements of the differential voltage response to transient currents provide a measurement of the polarization phenomena in formation as well as the capacitance of the casing in contact with the formation which is useful for determining whether oil and gas are present. Lithological characteristics of the formation such as the presence or absence of clay can also be determined. A calibration procedure is provided for minimizing errors induced by variations in the casing. The device also may be placed within the pipe attached to a drill bit while drilling open holes. 48 figures.

  2. Methods and apparatus for measurement of electronic properties of geological formations through borehole casing

    DOEpatents

    Vail, III, William B. (Bothell, WA)

    1991-01-01

    Methods and apparatus are provided for measuring electronic properties of geological formations and cement layers adjacent to cased boreholes including resistivities, polarization phenomena and dielectric constants. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. At least three voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the differential current conducted into formation in the vicinity of those electrodes. These measurements facilitate calculation of the resistivities of the adjacent geological formations as well as an indication of whether cement is present. Measurements of the differential voltage response to transient currents provide a measurement of the polarization phenomena in formation as well as the capacitance of the casing in contact with the formation which is useful for determining whether oil and gas present. Lithological characteristics of the formation such as the pressence or absence of clay can also be determined. A calibration procedure is provided for minimizing errors induced by variations in the casing. The device also may be placed within the pipe attached to a drill bit while drilling open holes.

  3. Evaluation of the geological relationships to gas hydrate formation and stability

    SciTech Connect

    Not Available

    1986-01-01

    Although there are many publications pertaining to gas hydrates, their formation and stability in various geological conditions are poorly known. Therefore, for the same reasons and because of the very broad scope of our research, limited amount and extremely dispersed information, the study regions are very large. Moreover, almost without exception the geological environments controlling gas hydrates formation and stability of the studied regions are very complex. The regions studied (completed and partially completed - total 17 locations) during the reporting period, particularly the Gulf of Mexico and the Middle America Trench, are the most important in this entire research project. In the past, both of these regions have been extensively studied, the presence of gas hydrates confirmed and samples recovered. In our investigation it was necessary not only to review all previous data and interpretations, but to do a thorough analysis of the basins, and a critical evaluation of an previously reported and publicly available but not published information.

  4. Method for controlling a producing zone of a well in a geological formation

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Byerly, Kent A. (Inventor); Amini, B. Jon (Inventor)

    2005-01-01

    System and methods for transmitting and receiving electromagnetic pulses through a geological formation. A preferably programmable transmitter having an all-digital portion in a preferred embodiment may be operated at frequencies below 1 MHz without loss of target resolution by transmitting and over sampling received long PN codes. A gated and stored portion of the received signal may be correlated with the PN code to determine distances of interfaces within the geological formation, such as the distance of a water interfaces from a wellbore. The received signal is oversampled preferably at rates such as five to fifty times as high as a carrier frequency. In one method of the invention, an oil well with multiple production zones may be kept in production by detecting an approaching water front in one of the production zones and shutting down that particular production zone thereby permitting the remaining production zones to continue operating.

  5. Method for Controlling a Producing Zone of a Well in a Geological Formation

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Byerly, Kent A. (Inventor); Amini, B. Jon (Inventor)

    2005-01-01

    System and methods for transmitting and receiving electromagnetic pulses through a geological formation. A preferably programmable transmitter having an all-digital portion in a preferred embodiment may be operated at frequencies below 1 MHz without loss of target resolution by transmitting and over sampling received long PN codes. A gated and stored portion of the received signal may be correlated with the PN code to determine distances of interfaces within the geological formation, such as the distance of a water interfaces from a wellbore. The received signal is oversampled preferably at rates such as five to fifty times as high as a carrier frequency. In one method of the invention, an oil well with multiple production zones may be kept in production by detecting an approaching water front in one of the production zones and shutting down that particular production zone thereby permitting the remaining production zones to continue operating.

  6. The formation of Hadley Rille and implications for the geology of the Apollo 15 region

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.; Swann, Gordon A.; Greeley, Ronald

    1988-01-01

    The results of studies of terrestrial lava tube systems and the regional and detailed site geology of the Apollo 15 area have been combined to develop a model for the formation of Hadley Rille. The regional geology of the Apennine bench formation and its relation to Mozart and Hadley Rilles is discussed. It is shown that the total thickness of mare basalt at the Apollo landing site is on the order of a few tens of meters, mostly less than 50 m. It is suggested that the role of thermal erosion in the development of sinuous rilles on the moon may be less important than previously assumed and that the assimilation of refractory highland rock types into mare basaltic magma is a minor lunar process.

  7. Methods and apparatus for measurement of the resistivity of geological formations from within cased boreholes

    DOEpatents

    Vail, III, William B. (Bothell, WA)

    1989-01-01

    Methods and apparatus are disclosed which allow measurement of the resistivity of a geological formation through borehole casing which may be surrounded by brine saturated cement. A.C. current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. The A.C. voltage difference is measured between two additional vertically disposed electrodes on the interior of the casing which provides a measure of the resistivity of the geological formation. A calibration and nulling procedure is presented which minimizes the influence of variations in the thickness of the casing. The procedure also minimizes the influence of inaccurate placements of the additional vertically disposed electrodes.

  8. Methods and apparatus for measurement of the resistivity of geological formations from within cased boreholes

    DOEpatents

    Vail, W.B. III.

    1989-04-11

    Methods and apparatus are disclosed which allow measurement of the resistivity of a geological formation through borehole casing which may be surrounded by brine saturated cement. A.C. current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. The A.C. voltage difference is measured between two additional vertically disposed electrodes on the interior of the casing which provides a measure of the resistivity of the geological formation. A calibration and nulling procedure is presented which minimizes the influence of variations in the thickness of the casing. The procedure also minimizes the influence of inaccurate placements of the additional vertically disposed electrodes. 3 figs.

  9. Universitt StuttgartInstitut fr Wasserbau, Lehrstuhl fr Hydromechanik und Hydrosystemmodellierung Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations

    E-print Network

    Cirpka, Olaf Arie

    Hydrosystemmodellierung Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations 1/16 Modelling April 2008 Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations #12 on Numerical Models for Carbon Dioxide Storage in Geological Formations 2/16 CO2 leakage mitigation using

  10. Experiences with the Application of Services Oriented Approaches to the Federation of Heterogeneous Geologic Data Resources

    NASA Astrophysics Data System (ADS)

    Cervato, C.; Fils, D.; Bohling, G.; Diver, P.; Greer, D.; Reed, J.; Tang, X.

    2006-12-01

    The federation of databases is not a new endeavor. Great strides have been made e.g. in the health and astrophysics communities. Reviews of those successes indicate that they have been able to leverage off key cross-community core concepts. In its simplest implementation, a federation of databases with identical base schemas that can be extended to address individual efforts, is relatively easy to accomplish. Efforts of groups like the Open Geospatial Consortium have shown methods to geospatially relate data between different sources. We present here a summary of CHRONOS's (http://www.chronos.org) experience with highly heterogeneous data. Our experience with the federation of very diverse databases shows that the wide variety of encoding options for items like locality, time scale, taxon ID, and other key parameters makes it difficult to effectively join data across them. However, the response to this is not to develop one large, monolithic database, which will suffer growth pains due to social, national, and operational issues, but rather to systematically develop the architecture that will enable cross-resource (database, repository, tool, interface) interaction. CHRONOS has accomplished the major hurdle of federating small IT database efforts with service-oriented and XML-based approaches. The application of easy-to-use procedures that allow groups of all sizes to implement and experiment with searches across various databases and to use externally created tools is vital. We are sharing with the geoinformatics community the difficulties with application frameworks, user authentication, standards compliance, and data storage encountered in setting up web sites and portals for various science initiatives (e.g., ANDRILL, EARTHTIME). The ability to incorporate CHRONOS data, services, and tools into the existing framework of a group is crucial to the development of a model that supports and extends the vitality of the small- to medium-sized research effort that is essential for a vibrant scientific community. This presentation will directly address issues of portal development related to JSR-168 and other portal API's as well as issues related to both federated and local directory-based authentication. The application of service-oriented architecture in connection with ReST-based approaches is vital to facilitate service use by experienced and less experienced information technology groups. Application of these services with XML- based schemas allows for the connection to third party tools such a GIS-based tools and software designed to perform a specific scientific analysis. The connection of all these capabilities into a combined framework based on the standard XHTML Document object model and CSS 2.0 standards used in traditional web development will be demonstrated. CHRONOS also utilizes newer client techniques such as AJAX and cross- domain scripting along with traditional server-side database, application, and web servers. The combination of the various components of this architecture creates an environment based on open and free standards that allows for the discovery, retrieval, and integration of tools and data.

  11. An exponential integrator for advection-dominated reactive transport in heterogeneous porous media

    E-print Network

    Lord, Gabriel

    media comprising geological for-4 mations. It is hence a fundamental process in many geo chemical reactions in highly heterogeneous porous media represen- tative of geological reservoirs, 2010 #12;non-linear advection dominated transport in geological formations. Key words: Exponential

  12. Vertical stratification of subsurface microbial community composition across geological formations at the Hanford Site

    SciTech Connect

    Lin, Xueju; Kennedy, David W.; Fredrickson, Jim K.; Bjornstad, Bruce N.; Konopka, Allan

    2011-11-29

    Microbial diversity in subsurface sediments at the Hanford Site 300 Area near Richland, Washington State (USA) was investigated by analyzing samples recovered from depths of 9 to 52 m. Approximately 8000 near full-length 16S rRNA gene sequences were analyzed across geological strata that include a natural redox transition zone. These strata included the oxic coarse-grained Hanford formation, fine-grained oxic and anoxic Ringold Formation sediments, and the weathered basalt group. We detected 1233 and 120 unique bacterial and archaeal OTUs (Operational Taxonomic Units at the 97% identity level), respectively. Microbial community structure and richness varied substantially across the different geological strata. Bacterial OTU richness (Chao1 estimator) was highest (>700) in the upper Hanford formation, and declined to about 120 at the bottom of the Hanford formation. Just above the Ringold oxic-anoxic interface, richness was about 325 and declined to less than 50 in the deeper reduced zones. The deeper Ringold strata were characterized by a preponderance (ca. 90%) of Proteobacteria. The Bacterial community in the oxic sediments contained not only members of 9 well-recognized phyla but also an unusually high proportion of 3 candidate divisions (GAL15, NC10, and SPAM). Additionally, novel phylogenetic orders were identified within the Delta-proteobacteria, a clade rich in microbes that carry out redox transformations of metals that are important contaminants on the Hanford Site.

  13. Vertical stratification of subsurface microbial community composition across geological formations at the Hanford Site.

    PubMed

    Lin, Xueju; Kennedy, David; Fredrickson, Jim; Bjornstad, Bruce; Konopka, Allan

    2012-02-01

    Microbial diversity in subsurface sediments at the Hanford Site 300 Area near Richland, Washington state (USA) was investigated by analysing 21 samples recovered from depths of 9-52?m. Approximately 8000 near full-length 16S rRNA gene sequences were analysed across geological strata that include a natural redox transition zone. These strata included the oxic coarse-grained Hanford formation, fine-grained oxic and anoxic Ringold Formation sediments, and the weathered basalt group. We detected 1233 and 120 unique bacterial and archaeal OTUs (operational taxonomic units at the 97% identity level) respectively. Microbial community structure and richness varied substantially across the different geological strata. Bacterial OTU richness (Chao1 estimator) was highest (>?700) in the upper Hanford formation, and declined to about 120 at the bottom of the Hanford formation. Just above the Ringold oxic-anoxic interface, richness was about 325 and declined to less than 50 in the deeper reduced zones. The deeper Ringold strata were characterized by a preponderance (c. 90%) of Proteobacteria. The bacterial community in the oxic sediments contained not only members of nine well-recognized phyla but also an unusually high proportion of three candidate divisions (GAL15, NC10 and SPAM). Additionally, 13 novel phylogenetic orders were identified within the Deltaproteobacteria, a clade rich in microbes that carry out redox transformations of metals that are important contaminants on the Hanford Site. PMID:22122741

  14. Geologic Mapping Applications Using THEMIS Data for the Medusae Fossae Formation, Mars

    NASA Technical Reports Server (NTRS)

    Zimbelman, J. R.; Bender, K. C.; Harris, J. C.

    2003-01-01

    The Medusae Fossae Formation (MFF) is a regionally extensive deposit located along the equator of Mars between roughly 130 and 240 E longitude, the origin of which has stimulated a host of published hypotheses. A volcanic or aeolian origin appear most consistent with Viking and MGS data, but other hypotheses remain viable and new data, as from the Mars Odyssey spacecraft, is likely to stimulate additional hypotheses of origin. NASA is supporting geologic mapping of portions of the MFF deposits, but it is now quite clear that this on-going mapping will need considerable revision as data from the Thermal Emission Imaging System (THEMIS) on Mars Odyssey become available. The daytime IR THEMIS images hold particularly strong potential for providing a new base on which geologic mapping can be carried out, as illustrated by the examples discussed.

  15. Structural and Geologic Mapping of Southern Tellus Regio, Venus: Implications for Crustal Plateau Formation

    NASA Astrophysics Data System (ADS)

    Graupner, Melanie

    Crustal plateau formation on Venus is subject to animated debate, centered on plateau support and resulting surface deformation. Detailed mapping provides critical clues for plateau evolution. Southern Tellus Regio records broadly synchronous formation of contractional and extensional structures, accompanied by deposition of flood material. Short-wavelength folds occur across the entire plateau, the extent of which has previously been undocumented. Generally the early-formed structures record a high structural fluidity, marked by variable orientation of structures or juxtaposition of neighboring structural suites. This interpretation of the geologic history of the region indicates the necessity of an extremely high geothermal gradient and provides a means to evaluate the different crustal plateau hypotheses. The mantle downwelling, mantle upwelling, and pulsating continents hypotheses fail to accommodate the surface features recorded in this study. However, the lava pond hypothesis provides a suitable hypothesis of crustal plateau formation that accommodates structural elements recorded in this study.

  16. Effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events

    DOE PAGESBeta

    Quan, Jiannong; Liu, Yangang; Liu, Quan; Li, Xia; Gao, Yang; Jia, Xingcan; Sheng, Jiujiang

    2015-09-30

    In this study, the effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events was investigated by analysis of comprehensive measurements of aerosol composition and concentrations [e.g., particular matters (PM2.5), nitrate (NO3), sulfate (SO4), ammonium (NH4)], gas-phase precursors [e.g., nitrogen oxides (NOx), sulfur dioxide (SO2), and ozone (O3)], and relevant meteorological parameters [e.g., visibility and relative humidity (RH)]. The measurements were conducted in Beijing, China from Sep. 07, 2012 to Jan. 16, 2013. The results show that the conversion ratios of N from NOx to nitrate (Nratio) and S from SO2 to sulfate (Sratio) bothmore »significantly increased in haze events, suggesting enhanced conversions from NOx and SO2 to their corresponding particle phases in the late haze period. Further analysis shows that Nratio and Sratio increased with increasing RH, with Nratio and Sratio being only 0.04 and 0.03, respectively, when RH ratio and Sratio to O3: the conversion ratios increase with decreasing O3 concentration when O3 concentration is lower than 3 when O3 concentration is higher than 15 ppb. The results suggest that heterogeneous aqueous reactions likely changed aerosols and their precursors during the haze events: in the beginning of haze events, the precursor gases accumulated quickly due to high emission and low reaction rate; the occurrence of heterogeneous aqueous reactions in the late haze period, together with the accumulated high concentrations of precursor gases such as SO2 and NOx, accelerated the formation of secondary inorganic aerosols, and led to rapid increase of the PM2.5 concentration.« less

  17. Heterogeneous Formation of Polar Stratospheric Clouds- Part 1: Nucleation of Nitric Acid Trihydrate (NAT)

    NASA Technical Reports Server (NTRS)

    Hoyle, C. R.; Engel, I.; Luo, B. P.; Pitts, M. C.; Poole, L. R.; Grooss, J.-U.; Peter, T.

    2013-01-01

    Satellite-based observations during the Arctic winter of 2009/2010 provide firm evidence that, in contrast to the current understanding, the nucleation of nitric acid trihydrate (NAT) in the polar stratosphere does not only occur on preexisting ice particles. In order to explain the NAT clouds observed over the Arctic in mid-December 2009, a heterogeneous nucleation mechanism is required, occurring via immersion freezing on the surface of solid particles, likely of meteoritic origin. For the first time, a detailed microphysical modelling of this NAT formation pathway has been carried out. Heterogeneous NAT formation was calculated along more than sixty thousand trajectories, ending at Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) observation points. Comparing the optical properties of the modelled NAT with these observations enabled a thorough validation of a newly developed NAT nucleation parameterisation, which has been built into the Zurich Optical and Microphysical box Model (ZOMM). The parameterisation is based on active site theory, is simple to implement in models and provides substantial advantages over previous approaches which involved a constant rate of NAT nucleation in a given volume of air. It is shown that the new method is capable of reproducing observed polar stratospheric clouds (PSCs) very well, despite the varied conditions experienced by air parcels travelling along the different trajectories. In a companion paper, ZOMM is applied to a later period of the winter, when ice PSCs are also present, and it is shown that the observed PSCs are also represented extremely well under these conditions.

  18. Lithofacies and cyclicity of the Yates Formation, Permian basin: Implications for reservoir heterogeneity

    SciTech Connect

    Borer, J.M.; Harris, P.M. )

    1991-04-01

    Siliciclastics of the Yates Formation (Permian, upper Guadalupian) are significant hydrocarbon reservoirs in the US Permian basin. Subsurface and outcrop data show that the most porous lithofacies occur in a clastic-dominated middle shelf and that evaporitic inner shelf and carbonate outer shelf equivalents are mostly nonporous. Lithofacies relations and much of the heterogeneity in Yates reservoirs are related to the stacking of depositional sequences (i.e., siliciclastic-carbonate alternations and sandstone-argillaceous siltstone alternations) in response to three orders of orbitally forced, low-amplitude, eustatic variation. In general, siliciclastics dominated the Yates shelf during lowstand parts of asymmetric, 400-k.y. sea level fluctuations, whereas carbonates were deposited during sea level highstands. The character and position of sand depocenters on the Yates shelf during these lowstands were controlled by a longer duration third-order sea level variation. Shorter duration cycles controlled the heterogeneity within the 400-k.y. depositional sequences. The variation in cycle packaging, lithology, and reservoir quality between the Central Basin platform and Northwest shelf may be a response of eustatic variation on parts of the shelf with different slopes or subsidence profiles. The lithofacies described from the Yates Formation and the deposition model proposed to explain the stratigraphy may be valuable as analogs in other basins containing mixed siliciclastic-carbonate settings.

  19. Crustal rheological strength heterogeneities control the formation of continental plateau margins

    NASA Astrophysics Data System (ADS)

    Liu, Chang; Zhu, Bojing; Yang, Xiaolin

    2015-08-01

    The margins bordering the Tibetan Plateau show two end-member morphologies in topographic gradient: steep margins and low-gradient margins. To investigate the formation mechanism of convergent intracontinental plateau margins, we conduct 2D numerical experiments to simulate crustal deformation process across plateau margins. Our numerical experiments demonstrate that heterogeneities in crustal rheological strength control significantly the formation of plateau margins when subjected to crustal convergence. A very steep margin is the result of crustal convergence between plateau with weak lower crust and foreland basin with strong lower crust. By contrast, a low-gradient margin could result from crustal convergence between plateau and foreland with less strength contrast. This finding suggests that the diversity in topographic gradient along the Tibetan Plateau borders reflects heterogeneities in crustal rheological strength across the plateau margins. Steep gradient at the margins indicate large crustal rheological strength contrasts between the weak ductile lower crust of the Tibetan Plateau and its strong surrounding foreland basins, like the Sichuan Basin, the Tarim Basin and the Qaidam Basin. Beneath these steep margins the horizontal flow of the Tibetan ductile lower crust is inhibited and forced to extrude to support escarpments. Low-gradient at the margins indicate less crustal strength variations between the plateau and outer forelands, like at the northeastern and southeastern margins, where they might be outlets for the weak ductile Tibetan lower crust to flow away from the plateau.

  20. Physical Constraints on Geologic CO2 Sequestration in Low-Volume Basalt Formations

    SciTech Connect

    Ryan M. Pollyea; Jerry P. Fairley; Robert K. Podgorney; Travis L. McLing

    2014-03-01

    Deep basalt formations within large igneous provinces have been proposed as target reservoirs for carbon capture and sequestration on the basis of favorable CO2-water-rock reaction kinetics that suggest carbonate mineralization rates on the order of 102–103 d. Although these results are encouraging, there exists much uncertainty surrounding the influence of fracture-controlled reservoir heterogeneity on commercial-scale CO2 injections in basalt formations. This work investigates the physical response of a low-volume basalt reservoir to commercial-scale CO2 injections using a Monte Carlo numerical modeling experiment such that model variability is solely a function of spatially distributed reservoir heterogeneity. Fifty equally probable reservoirs are simulated using properties inferred from the deep eastern Snake River Plain aquifer in southeast Idaho, and CO2 injections are modeled within each reservoir for 20 yr at a constant mass rate of 21.6 kg s–1. Results from this work suggest that (1) formation injectivity is generally favorable, although injection pressures in excess of the fracture gradient were observed in 4% of the simulations; (2) for an extensional stress regime (as exists within the eastern Snake River Plain), shear failure is theoretically possible for optimally oriented fractures if Sh is less than or equal to 0.70SV; and (3) low-volume basalt reservoirs exhibit sufficient CO2 confinement potential over a 20 yr injection program to accommodate mineral trapping rates suggested in the literature.

  1. Method of detecting leakage from geologic formations used to sequester CO.sub.2

    DOEpatents

    White, Curt (Pittsburgh, PA); Wells, Arthur (Bridgeville, PA); Diehl, J. Rodney (Pittsburgh, PA); Strazisar, Brian (Venetia, PA)

    2010-04-27

    The invention provides methods for the measurement of carbon dioxide leakage from sequestration reservoirs. Tracer moieties are injected along with carbon dioxide into geological formations. Leakage is monitored by gas chromatographic analyses of absorbents. The invention also provides a process for the early leak detection of possible carbon dioxide leakage from sequestration reservoirs by measuring methane (CH.sub.4), ethane (C.sub.2H.sub.6), propane (C.sub.3H.sub.8), and/or radon (Rn) leakage rates from the reservoirs. The invention further provides a method for branding sequestered carbon dioxide using perfluorcarbon tracers (PFTs) to show ownership.

  2. Paleogene mammals from the Iwaki Formation in Japan: Their implications for the geologic age and paleobiogeography of this formation

    NASA Astrophysics Data System (ADS)

    Tsubamoto, Takehisa; Koda, Yoshiki; Hasegawa, Yoshikazu; Nabana, Satoshi; Tomida, Yukimitsu

    2015-08-01

    The mammalian fauna and geologic age of the Iwaki Formation of the Paleogene Shiramizu Group (Iwaki, southern Fukushima, northeastern Japan) are reviewed and previously undescribed specimens are described. The Iwaki mammalian fauna consists of three artiodactyl species: Bothriogenys sp. cf. B. hui (Anthracotheriidae), Entelodon gobiensis (Entelodontidae), and cf. Notomeryx sp. (Ruminantia). These three genera indicate an Ergilian Asian Land Mamma Age (=late Eocene [Priabonian] equivalent) correlation for the Iwaki Formation, demonstrating that the Eocene-Oligocene boundary exists within the Shiramizu Group. These three genera have never co-occurred in a single formation, although in Asia they have been recorded only in the late Eocene. In Asia, Bothriogenys has been recorded in the southern and middle regions, Entelodon has been mostly recorded in the northern and middle regions with one exception from the southern region, and Notomeryx has been recorded in the southern region. The co-occurrence of these three genera in the Iwaki Formation implies that Bothriogenys, Entelodon, and perhaps also Notomeryx can be useful late Eocene indicators in terrestrial eastern Asia. It also suggests that the Iwaki mammalian fauna is paleobiogeographically located between the northern and southern late Eocene faunas of eastern Asia, showing some faunal mixture. The Iwaki fauna is also unique in comprising diverse faunas of marine sharks and seashore birds together with terrestrial mammals. The Iwaki vertebrate fauna is key for reconstructing the faunas of the eastern coastal margin of the Asian Continent during the late Eocene.

  3. Effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events

    NASA Astrophysics Data System (ADS)

    Quan, Jiannong; Liu, Quan; Li, Xia; Gao, Yang; Jia, Xingcan; Sheng, Jiujiang; Liu, Yangang

    2015-12-01

    The effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events was investigated by analysis of comprehensive measurements of aerosol composition and concentrations [e.g., particular matters (PM2.5), nitrate (NO3), sulfate (SO4), ammonium (NH4)], gas-phase precursors [e.g., nitrogen oxides (NOx), sulfur dioxide (SO2), and ozone (O3)], and relevant meteorological parameters [e.g., visibility and relative humidity (RH)]. The measurements were conducted in Beijing, China from Sep. 07, 2012 to Jan. 16, 2013. The results show that the conversion ratios of N from NOx to nitrate (Nratio) and S from SO2 to sulfate (Sratio) both significantly increased in haze events, suggesting enhanced conversions from NOx and SO2 to their corresponding particle phases in the late haze period. Further analysis shows that Nratio and Sratio increased with increasing RH, with Nratio and Sratio being only 0.04 and 0.03, respectively, when RH < 40%, and increasing up to 0.16 and 0.12 when RH reached 60-80%, respectively. The enhanced conversion ratios of N and S in the late haze period is likely due to heterogeneous aqueous reactions, because solar radiation and thus the photochemical capacity are reduced by the increases in aerosols and RH. This point was further affirmed by the relationships of Nratio and Sratio to O3: the conversion ratios increase with decreasing O3 concentration when O3 concentration is lower than <15 ppb but increased with increasing O3 when O3 concentration is higher than 15 ppb. The results suggest that heterogeneous aqueous reactions likely changed aerosols and their precursors during the haze events: in the beginning of haze events, the precursor gases accumulated quickly due to high emission and low reaction rate; the occurrence of heterogeneous aqueous reactions in the late haze period, together with the accumulated high concentrations of precursor gases such as SO2 and NOx, accelerated the formation of secondary inorganic aerosols, and led to rapid increase of the PM2.5 concentration.

  4. Effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events

    SciTech Connect

    Quan, Jiannong; Liu, Yangang; Liu, Quan; Li, Xia; Gao, Yang; Jia, Xingcan; Sheng, Jiujiang

    2015-09-30

    In this study, the effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events was investigated by analysis of comprehensive measurements of aerosol composition and concentrations [e.g., particular matters (PM2.5), nitrate (NO3), sulfate (SO4), ammonium (NH4)], gas-phase precursors [e.g., nitrogen oxides (NOx), sulfur dioxide (SO2), and ozone (O3)], and relevant meteorological parameters [e.g., visibility and relative humidity (RH)]. The measurements were conducted in Beijing, China from Sep. 07, 2012 to Jan. 16, 2013. The results show that the conversion ratios of N from NOx to nitrate (Nratio) and S from SO2 to sulfate (Sratio) both significantly increased in haze events, suggesting enhanced conversions from NOx and SO2 to their corresponding particle phases in the late haze period. Further analysis shows that Nratio and Sratio increased with increasing RH, with Nratio and Sratio being only 0.04 and 0.03, respectively, when RH < 40%, and increasing up to 0.16 and 0.12 when RH reached 60–80%, respectively. The enhanced conversion ratios of N and S in the late haze period is likely due to heterogeneous aqueous reactions, because solar radiation and thus the photochemical capacity are reduced by the increases in aerosols and RH. This point was further affirmed by the relationships of Nratio and Sratio to O3: the conversion ratios increase with decreasing O3 concentration when O3 concentration is lower than <15 ppb but increased with increasing O3 when O3 concentration is higher than 15 ppb. The results suggest that heterogeneous aqueous reactions likely changed aerosols and their precursors during the haze events: in the beginning of haze events, the precursor gases accumulated quickly due to high emission and low reaction rate; the occurrence of heterogeneous aqueous reactions in the late haze period, together with the accumulated high concentrations of precursor gases such as SO2 and NOx, accelerated the formation of secondary inorganic aerosols, and led to rapid increase of the PM2.5 concentration.

  5. Field Observation of Heterogeneous Formation of Secondary Organic Aerosols on Asian Mineral Dust Surfaces

    NASA Astrophysics Data System (ADS)

    Wang, G.

    2014-12-01

    This study investigated the heterogeneous formation mechanism of secondary organic aerosols (SOA) on dust surfaces by characterizing molecular compositions and size distributions of dicarboxylic acids, keto-carboxylic acids, a-dicarbonyls and inorganic ions in size-segregated aerosols (9-stages) in the urban atmosphere of Xi'an, China during dust storm periods and comparing with those in non-dust storm periods. In the presence of a dust storm, all the above mentioned SOA species in Xi'an are predominantly enriched on coarse particles (>2.1 µm). Oxalic acid well correlated with NO3- (r2=0.72, p<0.01) rather than SO42-. This phenomenon differs greatly from the observed particles during a non-dust storm period, which is characterized by an enrichment of the SOA on fine particles (<2.1 µm) with a strong correlation between C2 and SO42-. We propose a three-step formation pathway to explain these observations as follows. First, nitric acid and nitrogen oxides react with dust to form a liquid film on the surface via water vapor-absorption of calcium nitrate. Second, gaseous Gly and mGly partition into the aqueous-phase. Finally, the aqueous-phase Gly and mGly oxidize into glyoxylic acid (wC2), followed by a further oxidation into C2. To the best of our knowledge, we found for the first time the enrichments of glyoxal (Gly) and methylglyoxal (mGly) on dust surfaces. Our data indicate a more critical role of nitrate than sulfate in the heterogeneous formation process of SOA on dust surfaces. Mass ratio of C2 to wC2 was found to be higher in coarse particles than in fine particles during the dust storm events, which is due to low acidity condition of large particles that is favorable for conversion of wC2 to C2.

  6. Role of geomechanically grown fractures on dispersive transport in heterogeneous geological formations.

    PubMed

    Nick, H M; Paluszny, A; Blunt, M J; Matthai, S K

    2011-11-01

    A second order in space accurate implicit scheme for time-dependent advection-dispersion equations and a discrete fracture propagation model are employed to model solute transport in porous media. We study the impact of the fractures on mass transport and dispersion. To model flow and transport, pressure and transport equations are integrated using a finite-element, node-centered finite-volume approach. Fracture geometries are incrementally developed from a random distributions of material flaws using an adoptive geomechanical finite-element model that also produces fracture aperture distributions. This quasistatic propagation assumes a linear elastic rock matrix, and crack propagation is governed by a subcritical crack growth failure criterion. Fracture propagation, intersection, and closure are handled geometrically. The flow and transport simulations are separately conducted for a range of fracture densities that are generated by the geomechanical finite-element model. These computations show that the most influential parameters for solute transport in fractured porous media are as follows: fracture density and fracture-matrix flux ratio that is influenced by matrix permeability. Using an equivalent fracture aperture size, computed on the basis of equivalent permeability of the system, we also obtain an acceptable prediction of the macrodispersion of poorly interconnected fracture networks. The results hold for fractures at relatively low density. PMID:22181492

  7. Geologic framework of the Jurassic (Oxfordian) Smackover Formation the Alabama coastal waters area

    SciTech Connect

    Tew, B.H.; Mancini, E.A. ); Mink R.M.; Mann, S.D. ); Mancini, E.A.

    1993-09-01

    The Jurassic (Oxfordian) Smackover Formation is a prolific hydrocarbon-producing geologic unit in the onshore Gulf of Mexico area, including southwest Alabama. However, no Smackover strata containing commercial accumulations of oil or gas have thus far been discovered in the Alabama state coastal waters area (ACW). This study of the regional geologic framework of the Smackover Formation was done to characterize the unit in the ACW and to compare strata in the ACW with productive Smackover intervals in the onshore area. In the study area, the Smackover Formation was deposited on a highly modified carbonate associated with pre-Smackover topographic features. In the onshore Alabama, north of the Wiggins arch complex, an inner ramp developed in the area of the Mississippi interior salt basin and the Manila and Conecuh embayments. South of the Wiggins arch complex in extreme southern onshore Alabama and in the ACW, an outer ramp formed that was characterized by a much thicker Smackover section. In the outer ramp setting, four lithofacies associations are recognized: lower, middle, and upper outer ramp lithofacies (ORL) and the coastal dolostone lithofacies. The coastal dolostone lithofacies accounts for most of the reservoir-grade porosity in the outer ramp setting. The lower, middle, and upper ORL, for the most part, are nonporous. Volumetrically, intercrystalline porosity is the most important pore type in the coastal dolostone lithofacies. Numerous data in the ACW area indicate that halokinesis has created structural conditions favorable for accumulation and entrapment of oil and gas in the outer ramp lithofacies of the Smackover. Prolific hydrocarbon source rocks are present in the ACW, as evidenced by the significant natural gas accumulations in the Norphlet Formation. To date, however, reservoir quality rocks of the coastal dolostone lithofacies coincident with favorable structural conditions have not been encountered in the ACW.

  8. Psychoeducation in an Outpatient Setting--Designing a Heterogeneous Format for a Heterogeneous Population of Juvenile Delinquents.

    ERIC Educational Resources Information Center

    Carpenter, Patricia; Sugrue, Dennis P.

    1984-01-01

    Describes the G.I.T. (Getting It Together) program, a heterogeneous delinquent treatment program combining affective education and social skills training. Delinquents with immature personalities or neurotic features appeared to benefit more from the program than those with characterological disorders. (JAC)

  9. Geologic setting, petrophysical characteristics, and regional heterogeneity patterns of the Smackover in southwest Alabama. Draft topical report on Subtasks 2 and 3

    SciTech Connect

    Kopaska-Merkel, D.C.; Mann, S.D.; Tew, B.H.

    1992-06-01

    This is the draft topical report on Subtasks 2 and 3 of DOE contract number DE-FG22-89BC14425, entitled ``Establishment of an oil and gas database for increased recovery and characterization of oil and gas carbonate reservoir heterogeneity.`` This volume constitutes the final report on Subtask 3, which had as its primary goal the geological modeling of reservoir heterogeneity in Smackover reservoirs of southwest Alabama. This goal was interpreted to include a thorough analysis of Smackover reservoirs, which was required for an understanding of Smackover reservoir heterogeneity. This report is divided into six sections (including this brief introduction). Section two, entitled ``Geologic setting,`` presents a concise summary of Jurassic paleogeography, structural setting, and stratigraphy in southwest Alabama. This section also includes a brief review of sedimentologic characteristics and stratigraphic framework of the Smackover, and a summary of the diagenetic processes that strongly affected Smackover reservoirs in Alabama. Section three, entitled ``Analytical methods,`` summarizes all nonroutine aspects of the analytical procedures used in this project. The major topics are thin-section description, analysis of commercial porosity and permeability data, capillary-pressure analysis, and field characterization. ``Smackover reservoir characteristics`` are described in section four, which begins with a general summary of the petrographic characteristics of porous and permeable Smackover strata. This is followed by a more-detailed petrophysical description of Smackover reservoirs.

  10. Contaminant tailing in highly heterogeneous porous formations: Sensitivity on model selection and material properties

    NASA Astrophysics Data System (ADS)

    Maghrebi, Mahdi; Jankovic, Igor; Weissmann, Gary S.; Matott, L. Shawn; Allen-King, Richelle M.; Rabideau, Alan J.

    2015-12-01

    Coupled impacts of slow advection, diffusion and sorption were investigated using two heterogeneity models that differ in structure and in the mathematical framework that was used to simulate flow and transport and to quantify contaminant tailing. Both models were built using data from a highly heterogeneous exposure of the Borden Aquifer at a site located 2 km north-west of the Stanford-Waterloo experimental site at Canadian Forces Base Borden, Ontario, Canada. The inclusions-based model used a simplified representation of the different materials found at the site, while the second model was based on transitional probability geostatistics of the formation. These two models were used to investigate sensitivity of contaminant tailing on model selection and on geometric and material properties. While simulations were based on data collected at Borden, models were exercised beyond the geometric and material properties that characterize the site. Various realizations have identified very low conductive silty clay, found at volume fraction of 23.4%, as the material with dominant influence on tailing, and vertical diffusion in and out of low conductive units, affected by sorption, as the dominant transport mechanism causing tailing. The two models yielded almost identical transport results when vertical correlation lengths of silty clay were matched. Several practical implications relevant for characterization of low conductive units were identified and briefly discussed.

  11. Heterogeneous-nucleation and glass-formation studies of 56Ga2O3-44CaO

    NASA Technical Reports Server (NTRS)

    Ethridge, Edwin C.; Curreri, Peter A.; Pline, David

    1987-01-01

    Glass formation and heterogeneous crystallization are described for the reluctant-glass-forming 56Ga2O3-44CaO eutectic composition. The times and temperatures for nucleation at various cooling rates and experimental conditions were measured and empirical continuous-cooling-crystallization boundaries were constructed for various heterogeneous nucleation processes. A definition for an empirical critical cooling rate to form a glass from reluctant borderline glass formers is proposed, i.e., the cooling rate that results in glass formation in 95 percent of the quenching experiments.

  12. Modeling the effects of geological heterogeneity and metamorphic dehydration on slow slip and shallow deformation in subduction zones

    NASA Astrophysics Data System (ADS)

    Skarbek, Robert M.

    Slow slip and tectonic tremor in subduction zones take place at depths (˜20 - 50 km) where there is abundant evidence for distributed shear over broad zones (˜10 - 103 m) composed of rocks with marked differences in mechanical properties and for near lithostatic pore pressures along the plate interface where the main source of fluids must be attributed to chemical dehydration reactions. In Chapter II, I model quasi-dynamic rupture along faults composed of material mixtures characterized by different rate-and-state-dependent frictional properties to determine the parameter regime capable of producing slow slip in an idealized subduction zone setting. Keeping other parameters fixed, the relative proportions of velocity-weakening (VW) and velocity-strengthening (VS) materials control the sliding character (stable, slow, or dynamic) along the fault. The stability boundary between slow and dynamic is accurately described by linear analysis of a double spring-slider system with VW and VS blocks. In Chapter III, I model viscoelastic compaction of material subducting through the slow slip and tremor zone in the presence of pressure and temperature-dependent dehydration reactions. A dehydration fluid source is included using 1) a generalized basalt dehydration reaction in subducting oceanic crust or 2) a general nonlinear kinetic reaction rate law parameterized for an antigorite dehydration reaction. Pore pressures in excess of lithostatic values are a robust feature of simulations that employ parameters consistent with the geometry of the Cascadia subduction margin. Simulations that include viscous deformation uniformly generate traveling porosity waves that transport increased fluid pressures within the slow slip region. Slow slip and tremor also occur in shallow (< 10 km depth) accretionary prism sections of subduction zones. In Chapter IV, I examine how geologic heterogeneities affect the mechanics of accretionary prisms in subduction zones by showing how spatial variations in pore pressure, porosity, and internal friction coefficient affect predictions of basal shear stress, taper angle, and internal slip surface geometry. My results suggest that assuming average porosity throughout the prism may be a good approximation in many cases, but assuming an average value for the pore pressure can cause significant errors. This dissertation includes previously published and unpublished coauthored material.

  13. BIGFLOW: A numerical code for simulating flow in variably saturated, heterogeneous geologic media. Theory and user`s manaual, Version 1.1

    SciTech Connect

    Ababou, R.; Bagtzoglou, A.C.

    1993-06-01

    This report documents BIGFLOW 1.1, a numerical code for simulating flow in variably saturated heterogeneous geologic media. It contains the underlying mathematical and numerical models, test problems, benchmarks, and applications of the BIGFLOW code. The BIGFLOW software package is composed of a simulation and an interactive data processing code (DATAFLOW). The simulation code solves linear and nonlinear porous media flow equations based on Darcy`s law, appropriately generalized to account for 3D, deterministic, or random heterogeneity. A modified Picard Scheme is used for linearizing unsaturated flow equations, and preconditioned iterative methods are used for solving the resulting matrix systems. The data processor (DATAFLOW) allows interactive data entry, manipulation, and analysis of 3D datasets. The report contains analyses of computational performance carried out using Cray-2 and Cray-Y/MP8 supercomputers. Benchmark tests include comparisons with other independently developed codes, such as PORFLOW and CMVSFS, and with analytical or semi-analytical solutions.

  14. A dynamic flow simulation code benchmark study addressing the highly heterogeneous properties of the Stuttgart formation at the Ketzin pilot site

    NASA Astrophysics Data System (ADS)

    Kempka, Thomas; Class, Holger; Görke, Uwe-Jens; Norden, Ben; Kolditz, Olaf; Kühn, Michael; Walter, Lena; Wang, Wenqing; Zehner, Björn

    2013-04-01

    CO2 injection at the Ketzin pilot site located in Eastern Germany (Brandenburg) about 25 km west of Berlin is undertaken since June 2008 with a scheduled total amount of about 70,000 t CO2 to be injected into the saline aquifer represented by the Stuttgart Formation at a depth of 630 m to 650 m until the end of August 2013. The Stuttgart Formation is of fluvial origin determined by high-permeablity sandstone channels embedded in a floodplain facies of low permeability indicating a highly heterogeneous distribution of reservoir properties as facies distribution, porosity and permeability relevant for dynamic flow simulations. Following the dynamic modelling activities discussed by Kempka et al. (2010), a revised geological model allowed us to history match CO2 arrival times in the observation wells and reservoir pressure with a good agreement (Martens et al., 2012). Consequently, the validated reservoir model of the Stuttgart Formation at the Ketzin pilot site enabled us to predict the development of reservoir pressure and the CO2 plume migration in the storage formation by dynamic flow simulations. A benchmark study of industrial (ECLIPSE 100 as well as ECLIPSE 300 CO2STORE and GASWAT) and scientific dynamic flow simulations codes (TOUGH2-MP/ECO2N, OpenGeoSys and DuMuX) was initiated to address and compare the simulator capabilities considering a highly complex reservoir model. Hence, our dynamic flow simulations take into account different properties of the geological model such as significant variation of porosity and permeability in the Stuttgart Formation as well as structural geological features implemented in the geological model such as seven major faults located at the top of the Ketzin anticline. Integration of the geological model into reservoir models suitable for the different dynamic flow simulators applied demonstrated that a direct conversion of reservoir model discretization between Finite Volume and Finite Element flow simulators is not feasible. Hence, the initial hexahedron meshes as applied for the ECLIPSE 100 and TOUGH2-MP/ECO2N simulations had to be converted into tetrahedron meshes to meet the convergence criteria of the Finite Element simulators DuMuX and OpenGeoSys. Our simulation results show a good agreement of reservoir pressure between all simulators, while CO2 arrival times at the observation wells strongly depend on the chosen discretization. In summary, all simulators applied are capable to address the highly complex reservoir properties present in the Stuttgart Formation at the Ketzin pilot site by dynamic flow simulations providing results of sufficient quality for prediction of future site behaviour. References Kempka, T.; Kühn, M.; Class, H.; Frykman, P.; Kopp, A.; Nielsen, C.M.; Probst, P. (2010) Modelling of CO2 arrival time at Ketzin - Part I. International Journal of Greenhouse Gas Control, Special Issue Geological CO2 Storage 4(6):1007-1015. Martens, S.; Kempka, T.; Liebscher, A.; Lüth, S.; Möller, F.; Myrttinen, A.; Norden, B.; Schmidt-Hattenberger, C.; Zimmer, M.; Kühn, M. (2012): Europe's longest-operating on-shore CO2 storage site at Ketzin, Germany: a progress report after three years of injection. Environmental Earth Sciences. 10.1007/s12665-012-1672-5.

  15. Seasonal variability of heterogeneous ice formation in stratiform clouds over the Amazon Basin

    NASA Astrophysics Data System (ADS)

    Seifert, Patric; Kunz, Clara; Baars, Holger; Ansmann, Albert; Bühl, Johannes; Senf, Fabian; Engelmann, Ronny; Althausen, Dietrich; Artaxo, Paulo

    2015-07-01

    Based on 11 months of polarization lidar observations in the Amazon Basin near Manaus, Brazil (2.3°S, 60°W), the relationship between temperature and heterogeneous ice formation efficiency in stratiform clouds was evaluated in the cloud top temperature range between -40 and 0°C. Between -30 and 0°C, ice-containing clouds are a factor of 1.5 to 2 more frequent during the dry season. Free-tropospheric aerosol backscatter profiles revealed a twofold to tenfold increase in aerosol load during the dry season and a Monitoring Atmospheric Composition and Climate—Interim Implementation reanalysis data set implies that the aerosol composition during the dry season is strongly influenced by biomass burning aerosol, whereas other components such as mineral dust do not vary strongly between the seasons. The injection of smoke accompanied by the likely dispersion of biological material, soil dust, or ash particles was identified as a possible source for the increased ice formation efficiency during the dry season.

  16. Sudbury project (University of Muenster-Ontario Geological Survey): Petrology, chemistry, and origin of breccia formations

    NASA Technical Reports Server (NTRS)

    Stoeffler, D.; Deutsch, A.; Avermann, M.; Brockmeyer, P.; Lakomy, R.; Mueller-Mohr, V.

    1992-01-01

    Within the Sudbury Project of the University of Muenster and the Ontario Geological Survey special emphasis was put on the breccia formations exposed at the Sudbury structure (SS) because of their crucial role for the impact hypothesis. They were mapped and sampled in selected areas of the north, east, and south ranges of the SS. The relative stratigraphic positions of these units are summarized. Selected samples were analyzed by optical microscopy, SEM, microprobe, XRF and INAA, Rb-Sr and SM-Nd-isotope geochemistry, and carbon isotope analysis. The results of petrographic and chemical analysis for those stratigraphic units that were considered the main structural elements of a large impact basin are summarized.

  17. 3rd hand smoking; heterogeneous oxidation of nicotine and secondary aerosol formation in the indoor environment

    NASA Astrophysics Data System (ADS)

    Petrick, Lauren; Dubowski, Yael

    2010-05-01

    Tobacco smoking is well known as a significant source of primary indoor air pollutants. However, only recently has it been recognized that the impact of Tobacco smoking may continue even after the cigarette has been extinguished (i.e., third hand smoke) due to the effect of indoor surfaces. These surfaces may affect the fate of tobacco smoke in the form of secondary reactions and pollutants, including secondary organic aerosol (SOA) formation. Fourier Transform Infrared spectrometry with Attenuated Total Reflection (FTIR-ATR) in tandem with a Scanning Mobility Particle Sizing (SMPS) system was used to monitor the ozonation of cellulose sorbed nicotine and resulting SOA formation. SOA formation began at onset of ozone introduction ([O3] = 60 ± 5 ppb) with a size distribution of dp ? 25 nm, and was determined to be a result of heterogeneous reaction (opposed to homogeneous). SOA yield from reacted surface nicotine was on the order of 10 %. Simultaneous to SOA monitoring, FTIR-ATR spectra showed surface changes in the nicotine film as the reaction progressed, revealing a pseudo first-order surface reaction rate of 0.0026 ± 0.0008 min-1. Identified surface oxidation products included: cotinine, myosmine, methylnicotinamide and nicotyrine. Surface reaction rate was found to be partially inhibited at high relative humidity. Given the toxicity of some of the identified products (e.g., cotinine has shown potential mutagenicity and teratogenicity) and that small particles may contribute to adverse health effects, the present study indicates that exposure to 3rd hand smoke ozonation products may pose additional health risks.

  18. ELSEVIER Marine Geology 138(1997) 149-169 Geochemical constraints on the formation of Late Cenozoic

    E-print Network

    Johnson, Clark M.

    1997-01-01

    ELSEVIER Marine Geology 138(1997) 149-169 Geochemical constraints on the formation of Late Cenozoic Cenozoic Arctic seawater, oxide fractions were chemically separated from 15 samples of hand stratigraphic intervals of Late Cenozoic sediment indicate that oxide accretion occurred as a result

  19. Flow and Transport in Highly Heterogeneous Porous Formations: Numerical Experiments Performed Using the Analytic Element Method

    NASA Astrophysics Data System (ADS)

    Jankovic, I.

    2002-05-01

    Flow and transport in porous formations are analyzed using numerical simulations. Hydraulic conductivity is treated as a spatial random function characterized by a probability density function and a two-point covariance function. Simulations are performed for a multi-indicator conductivity structure developed by Gedeon Dagan (personal communication). This conductivity structure contains inhomogeneities (inclusions) of elliptical and ellipsoidal geometry that are embedded in a homogeneous background. By varying the distribution of sizes and conductivities of inclusions, any probability density function and two-point covariance may be reproduced. The multi-indicator structure is selected since it yields simple approximate transport solutions (Aldo Fiori, personal communication) and accurate numerical solutions (based on the Analytic Element Method). The dispersion is examined for two conceptual models. Both models are based on the multi-indicator conductivity structure. The first model is designed to examine dispersion in aquifers with continuously varying conductivity. The inclusions in this model cover as much area/volume of the porous formation as possible. The second model is designed for aquifers that contain clay/sand/gravel lenses embedded in otherwise homogeneous background. The dispersion in both aquifer types is simulated numerically. Simulation results are compared to those obtained using simple approximate solutions. In order to infer transport statistics that are representative of an infinite domain using the numerical experiments, the inclusions are placed in a domain that was shaped as a large ellipse (2D) and a large spheroid (3D) that were submerged in an unbounded homogeneous medium. On a large scale, the large body of inclusions behaves like a single large inhomogeneity. The analytic solution for a uniform flow past the single inhomogeneity of such geometry yields uniform velocity inside the domain. The velocity differs from that at infinity and can be used to infer the effective conductivity of the medium. As many as 100,000 inhomogeneities are placed inside the domain for 2D simulations. Simulations in 3D were limited to 50,000 inclusions. A large number of simulations was conducted on a massively parallel supercomputer cluster at the Center for Computational Research, University at Buffalo. Simulations range from mildly heterogeneous formations to highly heterogeneous formations (variance of the logarithm of conductivity equal to 10) and from sparsely populated systems to systems where inhomogeneities cover 95% of the volume. Particles are released and tracked inside the core of constant mean velocity. Following the particle tracking, various medium, flow, and transport statistics are computed. These include: spatial moments of particle positions, probability density function of hydraulic conductivity and each component of velocity, their two-point covariance function in the direction of flow and normal to it, covariance of Lagrangean velocities, and probability density function of travel times to various break-through locations. Following the analytic nature of the flow solution, all the results are presented in dimensionless forms. For example, the dispersion coefficients are made dimensionless with respect to the mean velocity and size of inhomogeneities. Detailed results will be presented and compared to well known first-order results and the results that are based on simple approximate transport solutions of Aldo Fiori.

  20. Formation of environmentally persistent free radicals from the heterogeneous reaction of ozone and polycyclic aromatic compounds.

    PubMed

    Borrowman, Cuyler K; Zhou, Shouming; Burrow, Timothy E; Abbatt, Jonathan P D

    2016-01-01

    In the 1980s long-lived radical species were identified in cigarette tar. Since then, environmentally persistent free radicals (EPFRs) have been observed in ambient particulate matter, and have been generated in particulate matter generated from internal combustion engines. For the first time, we measure in situ the formation and decay of EPFRs through the heterogeneous reaction of ozone and several polycyclic aromatic compounds (PAC). Solid anthracene (ANT), pyrene (PY), benzo[a]pyrene (BAP), benzo[ghi]perylene (BGHIP), 1,4-naphthoquinone (1,4NQ), and 9,10-anthraquinone (AQ) were reacted with gas-phase ozone in a flow system placed in the active cavity of an electron paramagnetic resonance (EPR) spectrometer, and the formation of radicals was measured on the timescale of tens of minutes at ambient levels of ozone down to 30 ppb. For most substrates the net radical production is initially rapid, slows at intermediate times, and is followed by a slow decay. For oxidized solid BAP, radical signal persists for many days in the absence of ozone. To evaluate the effect of substrate phase, the solid PAHs were also dissolved in squalane, an organic oil inert to ozone, which yielded a much higher maximum radical concentration and faster radical decay when exposed to ozone. With higher mobility, reactants were apparently able to more easily diffuse and react with each other, yielding the higher radical concentrations. The EPR spectra exhibit three radicals types, two of which have been assigned to semiquinone species and one to a PAH-derived, carbon-centered radical. Although our system uses levels of PAC not typically found in the environment it is worth noting that the amounts of radical formed, on the order of 10(18) radicals per g, are comparable to those observed in ambient particulate matter. PMID:26603953

  1. Transport of sorbing solutes in randomly heterogeneous formations: Spatial moments, macrodispersion, and parameter uncertainty

    SciTech Connect

    Andricevic, R.

    1993-06-01

    Expressions for the spatial moments and macrodispersion tensor for sorbing solutes in heterogeneous formations were presented using a probabilistic model of a fluid residence time coupled with the particle position analysis. The fluid residence time was defined as a fraction of the actual time during which the particle stayed in the mobile fluid phase of the aquifer. The fluid residence time is a random variable whose variability comes as a result of the non-equilibrium sorption properties. The sorbing solute was assumed to be governed with first-order linear kinetics. The closed-form expressions were based on the stationarity in the kinetic process and on the first-order approximation in the hydraulic conductivity field and in the fluid residence time. The non-equilibrium effects were presented as a function of the spatial variability in hydraulic conductivity and temporal variability in the fluid residence time. The importance of the non-equilibrium processes in the field scale was found to be dependent on reaction rates, retardation factor, mean velocity, and on variance and correlation scale of the hydraulic conductivity. The time needed to reach the asymptotic macrodispersivity is dependent on the degree of non-equilibrium processes and distribution coefficient. The impact from the uncertainty in parameters upon the spatial moments was examined and compared with the organic tracer used in the Borden field experiment.

  2. Conformism-driven phases of opinion formation on heterogeneous networks: the q-voter model case

    NASA Astrophysics Data System (ADS)

    Javarone, Marco Alberto; Squartini, Tiziano

    2015-10-01

    The q-voter model, a variant of the classic voter model, has been analyzed by several authors. While allowing us to study opinion dynamics, this model is also believed to be one of the most representative among the many defined in the wide field of sociophysics. Here, we investigate the consequences of conformity on the consensus reaching process, by numerically simulating a q-voter model with agents behaving either as conformists or nonconformists, embedded on heterogeneous network topologies (as small-world and scale-free). In fact, although it is already known that conformity enhances the reaching of consensus, the related process is often studied only on fully-connected networks, thus strongly limiting our full understanding of it. This paper represents a first step in the direction of analyzing more realistic social models, showing that different opinion formation phases, driven by the conformist agents density, are observable. As a result, we identify threshold values of the density of conformist agents, varying across different topologies and separating different regimes of our system, ranging from a disordered phase, where different opinions coexist, to a gradually more ordered phase, where consensus is eventually reached.

  3. Geology of the Molina Member of the Wasatch Formation, Piceance Basin, Colorado

    SciTech Connect

    Lorenz, J.; Nadon, G.; LaFreniere, L.

    1996-06-01

    The Molina Member of the Wasatch Formation has been cored in order to assess the presence/absence and character of microbial communities in the deep subsurface. Geological study of the Molina Member was undertaken in support of the microbiological tasks of this project, for the purposes of characterizing the host strata and of assessing the potential for post-depositional introduction of microbes into the strata. The Molina Member comprises a sandy fluvial unit within a formation dominated by mudstones. Sandy to conglomeratic deposits of braided and meandering fluvial systems are present on the western and eastern margins of the basin respectively, although the physical and temporal equivalence of these systems cannot be proven. Distal braided facies of planar-horizontal bedded sandstones are recognized on the western margin of the basin. Natural fractures are present in all Molina sandstones, commonly as apparent shear pairs. Core from the 1-M-18 well contains natural fractures similar to those found in outcrops, and has sedimentological affinities to the meandering systems of the eastern margin of the basin. The hydrologic framework of the Molina, and thus any potential post-depositional introduction of microbes into the formation, should have been controlled by approximately east-west flow through the natural fracture system, the geometries and extent of the sandstones in which the fractures occur, and hydraulic gradient. Migration to the well site, from outcropping recharge areas at the edge of the basin, could have started as early as 40 million years ago if the cored strata are connected to the eastern sedimentary system.

  4. Supercritical fluid behavior at nanoscale interfaces: implications for CO2 sequestration in geologic formations

    SciTech Connect

    Cole, David R; Chialvo, Ariel A; Rother, Gernot; Vlcek, L.; Cummings, Peter T

    2010-01-01

    Injection of CO2 into subsurface geologic formations has been identified as a key strategy for mitigating the impact of anthropogenic emissions of CO2. A key aspect of this process is the prevention of leakage from the host formation by an effective cap or seal rock which has low porosity and permeability characteristics. Shales comprise the majority of cap rocks encountered in subsurface injection sites with pore sizes typically less than 100 nm and whose surface chemistries are dominated by quartz (SiO2) and clays. We report the behavior of pure CO2 interacting with simple substrates, i.e. SiO2 and mica, that act as proxies for more complex mineralogical systems. Modeling of small-angle neutron scattering (SANS) data taken from CO2- silica aerogel (95% porosity; 6 nm pores) interactions indicates the presence of fluid depletion for conditions above the critical density. A theoretical framework, i.e. integral equation approximation (IEA), is presented that describes the fundamental behavior of near-critical adsorption onto a non-confining substrate that is consistent with SANS experimental results. Structural and dynamic behavior for supercritical CO2 interaction in K-mica slit pores was assessed by classical molecular dynamics (CMD). These results indicate the development of distinct layers of CO2 within slit pores, reduced mobility by one to two orders of magnitudes compared to bulk CO2 depending on pore size and formation of bonds between CO2 oxygens and H from mica hydroxyls. Analysis of simple, well-characterized fluid-substrate systems can provide details on the thermodynamic, structural and dynamic properties of CO2 at conditions relevant to sequestration.

  5. Geologically Controlled Isotope-Time Patterns Reveal Early Differentiation and Crust Formation Processes

    NASA Astrophysics Data System (ADS)

    Bennett, V. C.; Nutman, A. P.

    2014-12-01

    The mechanisms of continental crust production and evolution in the early Earth remain controversial, as are questions of the relative roles of early differentiation versus subsequent tectonic procssing in creating Earth's chemical signatures. Here we present geologic observations integrated with whole rock major, trace element and Sm-Nd isotopic signatures and combined with U-Pb and Lu-Hf isotopic compositions of zircon populations from the same rocks, from the most extensive early rock record comprising the 3.9 Ga to 3.6 Ga terranes of southwest Greenland. These data reveal repeated patterns of formation of juvenile TTG crust and associated mafic and ultramafic rocks in convergent margin settings followed by formation of more evolved granites [1]. Our new zircon Lu-Hf data from rare 3.6-3.7 Ga tonalites within the Itsaq Gneiss Complex, obtained from single component, non-migmatitic gneisses with simple zircon populations, limited within sample Hf isotopic variability and accurate U-Pb ages, now document extraction of juvenile tonalites from a near chondritic mantle source between 3.9 Ga and 3.6 Ga. The more evolved, granitic rocks in each area show slightly negative initial ?Hf in accord with crustal reworking of the older (3.8-3.9 Ga) gniesses. There is no evidence for Hadean material in the sources of the granitoids. The Hf isotope-time patterns are consistent with juvenile crust production from a mantle source that experienced only modest amounts of prior crustal extraction. They are distinct from those predicted by reprocessing of an enriched Hadean mafic crust, as has been proposed for this region [2] and for the source of the Hadean Jack Hills zircons [3]. The well-documented, time decreasing, positive 142Nd anomalies [e.g., 4] from these rocks are further evidence of crustal derivation from a convecting mantle source, rather than reworking of an enriched mafic lithosphere. The 143Nd isotopic -time patterns are more complex, reflecting the interplay between early Sm/Nd fractionation processes as required by the 142Nd data, juvenile crustal growth and in some cases geologic disturbance of the whole rock Sm-Nd system. [1] Nutman, et al, (2013) Amer. Jour. Sci. 313, 877-911. [2] Naeraa et al.. (2012) Nature 485, 627-631. [3] Kemp et al., (2010) EPSL 296, 45-56. [4] Bennett et al., (20070 Science 318, 1907.

  6. DIGITAL CHROMATOGRAPHY AND THE FORMA-TION OF HETEROGENEOUS DROPLET LIBRARIES

    E-print Network

    Basu, Amar S.

    DIGITAL CHROMATOGRAPHY AND THE FORMA- TION OF HETEROGENEOUS DROPLET LIBRARIES USING University, Detroit MI, USA ABSTRACT Generating chemical libraries in droplet form is vital to the adoption in droplets (µFD), a method for generating heterogeneous droplet libraries using standard separation processes

  7. Models for large-scale Simulation of CO2-Storage in geological Formations

    NASA Astrophysics Data System (ADS)

    Class, Holger; Walter, Lena

    2010-05-01

    Carbon dioxide Capture and Storage (CCS) is a technology that is currently developed for mitigating global greenhouse gas emissions while fossil fuel combustion still is a main pillar for energy production in the next couple of decades. CO2 is captured from large fossil-fuelled (mostly coal) power plants, then transported to a storage site, and eventually injected into a deep geological formation. Modelling CO2 storage in saline aquifers on a reservoir scale is demanding with respect to the complexity of the non-linear processes occurring on different spatial and tempora scales as well as with respect to computational costs. Large and complex geometries need to be described for a realistic scenario. The models need to be able to describe non-isothermal, multiphase and compositional processes that occur during CO2 storage. In most cases, it is not necessary to describe all the physical processes for the entire simulation time period. Especially for CO2 storage the dominating processes vary over time. During and shortly after the injection, the plume evolution in the formation is dominated by advective multiphase processes driven by viscous and buoyant forces. Moreover, the non-isothermal behaviour in the vicinity of the expanding plume due to the Joule Thompson effect needs to be described. With increasing time scale, the dissolution of CO2 into the brine, compositional effects, diffusion and density-driven brine-convection become more and more important and cannot be neglected when modelling over large time periods. Considering this time-dependent behaviour, it is possible to describe a certain time scale with models of reduced/adapted complexity. For the simulation of the short-term behaviour a non-isothermal two-phase model can be applied whereas the long-term behaviour can be described with a two-phase two-component model, neglecting non-isothermal effects. By coupling these models of reduced complexity, the model efficiency is increased without neglecting the relevant phenomena.

  8. Nuclear Waste Disposal in Deep Geological Formations: What are the Major Remaining Scientific Issues?

    SciTech Connect

    Toulhoat, Pierre

    2007-07-01

    For more than thirty years, considerable efforts have been carried out in order to evaluate the possibility of disposing of high level wastes in deep geological formations. Different rock types have been examined, such as water-under-saturated tuffs (USA), granites or crystalline rocks (Canada, Sweden, and Finland), clays (France, Belgium, and Switzerland), rock-salt (Germany). Deep clays and granites, (provided that the most fractured zones are avoided in the second case) are considered to fulfill most allocated functions, either on short term (reversibility) or long term. Chemically reducing conditions favor the immobilization of actinides and most fission products by precipitation, co-precipitation and sorption. If oxidizing conditions prevail, the safety demonstration will mostly rely on the performance of artificial confinement systems. Rock-salt offers limited performance considering the issue of reversibility, which is now perceived as essential, mostly for ethical and sociological reasons. However, several issues would deserve additional research programs, and as a first priority, a clear description of time/space succession of processes during the evolution of the repository. This will allow a better representation of coupled processes in performance assessment, such as the influence of gases (H{sub 2}) generated by corrosion, on the long term dynamics of the re-saturation. Geochemical interactions between the host formation and the engineered systems (packages + barriers) are still insufficiently described. Additional gains in performance could be obtained when taking into account processes such as isotopic exchange. Imaginative solutions, employing ceramic- carbon composite materials could be proposed to replace heavy and gas-generating overpacks, or to accommodate the small but probably significant amount of 'ultimate' wastes that will be inevitably produced by Generation IV reactor systems. (author)

  9. Geologic reservoir model for the Triassic Doig Formation, northeast British Columbia, Canada

    SciTech Connect

    Moslow, T.F. ); Munroe, H.D. )

    1991-03-01

    A subsurface investigation of the mid-Triassic Doig formation in northeastern British Columbia documented two main reservoir facies. Both are a product of mass movement and sediment gravity flow processes on a progradational, tectonically active continental shelf margin. Substrate instability was likely a product of sediment loading, perhaps in concert with seismic activity. Sedimentary facies and reservoir parameters were determined from analysis of approximately 150 cores and 900 well logs. Laterally discontinuous Doig sandstones are up to 60 m thick and trend northeasterly within the study area. The main reservoir facies are incised density flow deposits and laterally extensive slump deposits. Reservoir quality within these sands is extremely variable with porosity ranging from less than 5% to 15%. In core, these deposits consist of moderately well sorted, very fine grained sandstones with no vertical grain size variation. The best production to date is in the Buick Creek field with initial flows of 346 BOPD. The slump deposits are thinner and tend to be more elongate parallel to paleoshoreline. These sands were subject to some wave or current reworking. Modern analogs where similar processes and products of deposition are known to occur include the Gulf of Alaska continental shelf and the Fraser River Delta slope. Doig sandstones usually are enclosed in fine-grained shelf deposits that provide a good stratigraphic trapping mechanism. Successful development of Doig reservoirs must incorporate geologic modes that assist in understanding the complex and highly variable reservoir quality of sandstones units.

  10. Geological factors controlling the utility of refractory dolomite: The Cambrian Ledger Formation dolomite, a case study

    SciTech Connect

    Furman, F.C.; Gregg, J.M.; Ablin, V.C.; Moore, R.E. )

    1993-03-01

    The Middle Cambrian Ledger Formation in eastern Pennsylvania is a high purity, single-stage-sintering dolomite. It yields high quality, direct bonded, environmentally clean, doloma bricks for steel, cement and lime industries use. Geological properties are controlled by the depositional environment, diagenesis, metamorphism, deformation, and rifting. The Middle Cambrian was a time of high sea level stand, high evaporation, low volcanism, and absence of land plants. This produced carbonates low in SiO[sub 2], Al[sub 2]O[sub 3], and Fe[sub 2]O[sub 3] (< 1%). Uniform oolite shoals developed on fault blocks. Early diagenesis dolomitized the [approx]1 mm oolites. The Taconic-Acadian Orogeny greenschist-metamorphism annealed the dolomite by heating it to 300--400 C, at [approx]2 kbar, for [approx]200 million years. This produced a homogeneous coarse crystalline, nonporous, nonplanar dolomite with uniform grain chemistry. Alleghenian overthrusting strained the dolomite, producing deformed oolite ghosts, and minor strain twins. Time, temperature, pressure, and strain increases sinterability and thus suitability of the dolomite for refractory purposes. Near Triassic faults the quality of the brickstone grade dolomite has been degraded to fettling and agricultural grade dolomite. Faulting produced dolomite twinning, polymictic brecciation, and fracture porosity. Karstification generated quartz, feldspar and hematite that filled the porosity. Triassic intrusions partial recrystallized the dolomite incorporating the impurities and thereby degrading it.

  11. Kinetics of oxygenated product formation during the heterogeneous oxidation of organic aerosol

    NASA Astrophysics Data System (ADS)

    Kolesar, K. R.; Cappa, C. D.; Wilson, K. R.

    2014-12-01

    Oxidation of organic aerosols can lead to changes in their atmospheric lifetime, optical properties and health effects. Whereas much is known about the rates of reaction and subsequent branching ratios of gas-phase organic species, much less is known about their condensed phase counterparts. The determination of the kinetics and abundances of the oxidation products associated with condensed phase reactions is needed to understand the oxidation reaction pathways and their branching ratios. The Vacuum Ultraviolet Aerosol Mass Spectrometer (VUV-AMS) at the Chemical Dynamics Beamline at Lawrence Berkeley National Laboratory has been useful in determining the reaction rate constants for a number of condensed phase organic compounds with oxidants such as OH and O3. The relatively soft ionization in the VUV-AMS leads to substantially less fragmentation than other AMS instruments that use electron impact ionization, and therefore preserves a greater amount of molecular information about parent molecules. Previously, ketones formed from the heterogenous oxidation of model organic compounds have been identified and their formation kinetics quantified. However, other possible products, such as alcohols and organic peroxides, have not previously been identified in the VUV-AMS mass spectra or characterized as these are subject to greater fragmentation. Here, we present a method in which the fragmentation pattern is specified for each alcohol isomer formed from the oxidation of two model organic compounds, bis-2-ethylhexl sebacate and squalane. From this we are able to define unique m/z fragments for each isomer from which we derive information about alcohol and abundances. This study demonstrates additional methods for the analysis of mass spectra obtained with the VUV-AMS as well as provides insights into condensed phase oxidation kinetics.

  12. Fibril Film Formation of Pseudoenantiomeric Oxymethylenehelicene Oligomers at the Liquid-Solid Interface: Structural Changes, Aggregation, and Discontinuous Heterogeneous Nucleation.

    PubMed

    Shigeno, Masanori; Sawato, Tsukasa; Yamaguchi, Masahiko

    2015-12-01

    Oxymethylenehelicene (P)- and (M)-oligomers up to a nonamer were synthesized by a building block method. The oligomers formed dimeric homoaggregates in trifluoromethylbenzene. A mixture of the pseudoenantiomeric (P)-pentamer and (M)-hexamer formed a heteroaggregate, which self-assembled into one-dimensional fibril films at the liquid-solid interface. Discontinuous heterogeneous nucleation occurred, which involved the formation of particles that were 50?nm in diameter and subsequent fibril growth from these particles. The fibril film was formed on the solid surface and the molecules remained dissociated in solution. The fibril film formation was affected by seeding and the solid surface materials. PMID:26477675

  13. Capacity investigation of brine-bearing sands of the Fwwm formation for geologic sequestration of CO{sub 2}

    SciTech Connect

    Doughty, Christine; Pruess, Karsten; Benson, Sally M.; Hovorka, Susan D.; Knox, Paul R.; Green, Christopher T.

    2001-05-01

    The capacity of fluvial brine-bearing formations to sequester CO{sub 2} is investigated using numerical simulations of CO{sub 2} injection and storage. Capacity is defined as the volume fraction of the subsurface available for CO{sub 2} storage and is conceptualized as a product of factors that account for two-phase flow and transport processes, formation geometry, formation heterogeneity, and formation porosity. The space and time domains used to define capacity must be chosen with care to obtain meaningful results, especially when comparing different authors' work. Physical factors that impact capacity include permeability anisotropy and relative permeability to CO{sub 2}, brine/CO{sub 2} density and viscosity ratios, the shape of the trapping structure, formation porosity and the presence of low-permeability layering.

  14. Microbial and Chemical Enhancement of In-Situ Carbon Mineralization in Geological Formation

    SciTech Connect

    Matter, J.; Chandran, K.

    2013-05-31

    Predictions of global energy usage suggest a continued increase in carbon emissions and rising concentrations of CO{sub 2} in the atmosphere unless major changes are made to the way energy is produced and used. Various carbon capture and storage (CCS) technologies are currently being developed, but unfortunately little is known regarding the fundamental characteristics of CO{sub 2}-mineral reactions to allow a viable in-situ carbon mineralization that would provide the most permanent and safe storage of geologically-injected CO{sub 2}. The ultimate goal of this research project was to develop a microbial and chemical enhancement scheme for in-situ carbon mineralization in geologic formations in order to achieve long-term stability of injected CO{sub 2}. Thermodynamic and kinetic studies of CO{sub 2}-mineral-brine systems were systematically performed to develop the in-situ mineral carbonation process that utilizes organic acids produced by a microbial reactor. The major participants in the project are three faculty members and their graduate and undergraduate students at the School of Engineering and Applied Science and at the Lamont-Doherty Earth Observatory at Columbia University: Alissa Park in Earth and Environmental Engineering & Chemical Engineering (PI), Juerg Matter in Earth and Environmental Science (Co-PI), and Kartik Chandran in Earth and Environmental Engineering (Co-PI). Two graduate students, Huangjing Zhao and Edris Taher, were trained as a part of this project as well as a number of graduate students and undergraduate students who participated part-time. Edris Taher received his MS degree in 2012 and Huangjing Zhao will defend his PhD on Jan. 15th, 2014. The interdisciplinary training provided by this project was valuable to those students who are entering into the workforce in the United States. Furthermore, the findings from this study were and will be published in referred journals to disseminate the results. The list of the papers is given at the end of the report for reference.

  15. Composite catalyst surfaces: Effect of inert and active heterogeneities on pattern formation

    SciTech Connect

    Baer, M.; Bangia, A.K.; Kevrekidis, I.G.; Haas, G.; Rotermund, H.H.; Ertl, G.

    1996-12-05

    Spatiotemporal dynamics in reaction-diffusion systems can be altered through the properties (reactivity, diffusivity) of the medium in which they occur. We construct active heterogeneous media (composite catalytic surfaces with inert as well as active illusions) using microelectronics fabrication techniques and study the spatiotemporal dynamics of heterogeneous catalytic reactions on these catalysts. In parallel, we perform simulations as well as numerical stability and bifurcation analysis of these patterns using mechanistic models. At the limit of large heterogeneity `grain size` (compared to the wavelength of spontaneously arising structures) the interaction patterns with inert or active boundaries dominates (e.g., pinning, transmission, and boundary breakup of spirals, interaction of pulses with corners, `pacemaker` effects). At the opposite limit of very small or very finely distributed heterogeneity, effective behavior is observed (slight modulation of pulses, nearly uniform oscillations, effective spirals). Some representative studies of transitions between the two limits are presented. 48 refs., 11 figs.

  16. Effects of heterogeneous soil-water diffusivity on vegetation pattern formation

    NASA Astrophysics Data System (ADS)

    Yizhaq, H.; Sela, S.; Svoray, T.; Assouline, S.; Bel, G.

    2014-07-01

    Many mathematical models have been proposed to explain the emergence of vegetation patterns in arid and semiarid environments, but only a few of them take into account the heterogeneity in the system properties. Here we present a rigorous study of the effects of heterogeneous soil-water diffusivity on vegetation patterns, using two mathematical models. The two models differ in the pattern-forming feedback that they capture; one model captures the infiltration contrast between vegetated and bare-soil domains, whereas the other model captures the increased growth rate of denser vegetation due to an enhanced ability to extract water from the soil. In both models, the most significant effect of the heterogeneity on the soil-water diffusivity is the increased durability of patterned vegetation to a reduced precipitation rate. An additional effect is that the heterogeneity makes the desertification process, namely, the transition from a spotted vegetation pattern to a bare-soil state, more gradual than in the homogeneous system. Our findings suggest that the heterogeneity cannot be neglected in the study of critical transitions in heterogeneous ecosystems and, particularly, in the study of the desertification process due to climate changes or anthropogenic disturbances.

  17. Effect of crustal heterogeneities and effective rock strength on the formation of HP and UHP rocks.

    NASA Astrophysics Data System (ADS)

    Reuber, Georg; Kaus, Boris; Schmalholz, Stefan; White, Richard

    2015-04-01

    The formation of high pressure and ultra-high pressure rocks has been controversially discussed in recent years. Most existing petrological interpretations assume that pressure in the Earth is lithostatic and therefore HP and UHP rocks have to come from great depth, which usually involves going down a subduction channel and being exhumed again. Yet, an alternative explanation points out that pressure in the lithosphere is often non-lithostatic and can be either smaller or larger than lithostatic as a function of location and time. Whether this effect is tectonically significant or not depends on the magnitude of non-lithostatic pressure, and as a result a number of researchers have recently performed numerical simulations to address this. Somewhat disturbingly, they obtained widely differing results with some claiming that overpressures as large as a GPa can occur (Schmalholz et al. 2014), whereas others show that overpressures of exhumed rocks are generally less than 20% and thus insignificant (Li et al. 2010; Burov et al. 2014). In order to understand where these discrepancies come from, we reproduce the simulations of Li et al (2010) of a typical subduction and collision scenario, using an independently developed numerical code (MVEP2). For the same model setup and parameters, we confirm the earlier results of Li et al. (2010) and obtain no more than ~20% overpressure in exhumed rocks of the subduction channel. Yet, a critical assumption in their models is that the subducted crust is laterally homogeneous and that it has a low effective friction angle that is less than 7o. The friction angle of (dry) rocks is experimentally well-constrained to be around 30o, and low effective friction angles require, for example, high-fluid pressures. Whereas high fluid pressures might exist in the sediment-rich upper crust, they are likely to be much lower or absent in the lower crust from which melt has been extracted or in rocks that underwent a previous orogenic cycle. In a next step, we performed several hundred numerical simulations to understand the effects of km-scale heterogeneities and material parameters on pressure magnitudes, using a model setup that is otherwise very similar to the one of Li et al. (2010). Results show that significant non-lithostatic pressures occur if (lower) crustal rocks are dry or if km-scale (nappe-sized) heterogeneities with dryer rocks are present within the crust. Overpressure magnitudes can be up to 1 GPa or 100% and in some cases rock assemblages are temporarily in the coesite stability field at a depth of only 40 km, followed by rapid exhumation to the surface. Tectonic overpressures can vary strongly in magnitude versus time, but peak pressures are present sufficiently long for metamorphic reactions to occur. The presence of heterogeneities can affect the crustal-scaled deformation pattern, and the effective friction angle of crustal-scale rocks (or the dryness of these rocks) is a key parameter that determines the magnitude of non-lithostatic pressures. Our results thus reconcile previous findings and highlight the importance of having an accurate knowledge of the fluid-pressure, initial crustal structure and rock composition during continental collision. If rocks are dry by the time they enter a subduction zone, or are stronger/dryer than surrounding rocks, they are likely to develop significantly higher pressures than nearby rocks. This might explain the puzzling observation that some nappes have very high peak pressures, while juxtaposed nappes have much lower values, without clear structural evidence for deep burial and exhumation along a subduction channel of the high-pressure nappe. Our models might also give a partial explanation of why the reported timescales for high and ultra-high pressure stages of peak metamorphism are often very short. References: Burov, E., Francois, T., Agard, P., Le Pourhiet, L., Meyer, B., Tirel, C., Lebedev, S., Yamato, P., Brun, J.-P., 2014. Tectonophysics. Tectonophysics 631, 212-250. doi:10.1016/j.tecto.2014.04.033 Li, Z.H., Gerya, T.V., Burg, J.-P., 20

  18. Numerical Simulation of Behavior of Carbon Dioxide Injected into Target Geologic Formations in the Bukpyeong Basin, Korea

    NASA Astrophysics Data System (ADS)

    Kihm, J.; Park, S.; Kim, J.

    2013-12-01

    A series of thermo-hydrological numerical simulations was performed to predict and analyze behavior of carbon dioxide injected into target geologic formations in the Bukpyeong Basin, which is one of the prospective offshore basins for geologic carbon dioxide storage in Korea. The results of the numerical simulations for the two areas in the basin show that the spatial distribution, structure (layered structure), and hydrological properties (anisotropy of intrinsic permeability) of the target geologic formations have significant impacts on three-dimensional behavior of carbon dioxide injected. The horizontal movement of carbon dioxide along the spatial distribution of a target geologic formation (Unit C-4) is more dominant than the vertical movement. As the injection amount of carbon dioxide increases, carbon dioxide plume expands furthermore and reaches to the shallower depth region from the mean sea level. Even in case of the maximum injection amount of carbon dioxide, carbon dioxide does not leak through the top boundary (sea floor) of the modeling domain for both areas. It indicates that carbon dioxide can be stored in the two areas up to their effective storage capacities of free fluid phase carbon dioxide, which was estimated in authors' previous study. As time progresses, carbon dioxide stored by hydrodynamic trapping decreases, while carbon dioxide stored by solubility trapping increases. The total mass of carbon dioxide stored by solubility trapping evaluated in this study is significantly greater than that estimated in authors' previous study. It indicates that the storage efficiency of aqueous phase carbon dioxide is greater than that of free fluid phase carbon dioxide. Therefore, this difference in the storage efficiencies of the free fluid and aqueous phases of carbon dioxide must be properly considered when more rigorous effective storage capacities of carbon dioxide are to be estimated on basin and even site scales. This work was supported by the Energy Efficiency and Resources Program funded by the Korea Institute of Energy Technology Evaluation and Planning (KETEP), Ministry of Trade, Industry and Energy, Republic of Korea.

  19. Evidence for Regional Basin Formation in Early Post-Tessera Venus History: Geology of the Lavinia Planitia Area (V55)

    NASA Technical Reports Server (NTRS)

    Head, J. W.; Ivanov, M. A.

    1995-01-01

    On Venus, global topography shows the presence of highs and lows including regional highly deformed plateaus (tesserae), broad rifted volcanic rises, linear lows flanking uplands, and more equidimensional lowlands (e.g. Lavinia and Atalanta planitiae) Each of these terrain types on Venus has relatively distinctive characteristics, but origins are uncertain in terms of mode of formation, time of formation, and potential evolutionary links. There is a high level of uncertainty about the formation and evolution of lowlands on Venus. We have undertaken the mapping of a specific lowlands region of Venus to address several of these major questions. Using geologic mapping we have tried to establish: What is the sequence of events in the formation and evolution of large-scale equidimensional basins on Venus? When do the compressional features typical of basin interiors occur? What is the total volume of lava that occurs in the basins and is this similar to other non-basin areas? How much subsidence and downwarping has occurred after the last major plains units? WE have undertaken an analysis of the geology of the V55 Lavinia Planitia quadrangle in order to address many of these issues and we report on the results here.

  20. Geology, structure and age of the Nahuel Niyeu Formation in the Aguada Cecilio area, North Patagonian Massif, Argentina

    NASA Astrophysics Data System (ADS)

    Greco, Gerson A.; González, Pablo D.; González, Santiago N.; Sato, Ana M.; Basei, Miguel A. S.; Tassinari, Colombo C. G.; Sato, Kei; Varela, Ricardo; Llambías, Eduardo J.

    2015-10-01

    The low-grade Nahuel Niyeu Formation in the Aguada Cecilio area (40°50?S-65°53?W) shows ultramafic to felsic metaigneous rocks forming a sill swarm intercalated in the metasedimentary sequence and a polyphase deformation which permit an integrated study of the magmatic and tectonometamorphic evolution of this geological unit. In this paper we present a geological characterization of the Nahuel Niyeu Formation in the Aguada Cecilio area combining mapping, structural and metamorphic analysis with a SHRIMP U-Pb age and geochemical data from the metaigneous rocks. The metasedimentary sequence consists of alternating metagreywackes and phyllites, and minor metasandstones and granule metaconglomerates. The sills are pre-kinematic intrusions and yielded one SHRIMP U-Pb, zircon crystallization age of 513.6 ± 3.3 Ma. Their injection occurred after consolidation of the sedimentary sequence. A syn-sedimentary volcanic activity is interpreted by a metaandesite lava flow interlayered in the metasedimentary sequence. Sedimentary and igneous protoliths of the Nahuel Niyeu Formation would have been formed in a continental margin basin associated with active magmatic arc during the Cambrian Epoch 2. Two main low-grade tectonometamorphic events affected the Nahuel Niyeu Formation, one during the Cambrian Epoch 2-Early Ordovician and the other probably in the late Permian at ?260 Ma. Local late folds could belong to the final stages of the late Permian deformation or be even younger. In a regional context, the Nahuel Niyeu and El Jagüelito formations and Mina Gonzalito Complex show a comparable Cambrian-Ordovician evolution related to the Terra Australis Orogen in the south Gondwana margin. This evolution is also coeval with the late and early stages of the Pampean and Famatinian orogenies of Central Argentina, respectively. The late Permian event recorded in the Nahuel Niyeu Formation in Aguada Cecilio area is identified by comparable structures affecting the Mina Gonzalito Complex and El Jagüelito Formation and resetting ages from granitoids. This event represents the Gondwanide Orogeny within the same Terra Australis Orogen.

  1. a Key for 'STABLE' Sequestration of CO2 in Geological Reservoirs: the Formation of Carbonate Minerals

    NASA Astrophysics Data System (ADS)

    Lopez, O.; Zuddas, P.

    2007-12-01

    CO2 injections in brine aquifers strongly modify the physic and the chemistry of the host aquifer affecting mainly the calcite precipitation kinetics. Classically precipitation laboratory experiments link the precipitation rate (the dependent variable) to one or more independent variables. In this work we evaluated the mutual influence of pCO2 partial pressure, temperature, ionic strength (or salinity), major components and known calcite inhibitors (Mg, SO4, dissolved organic matter) in the complex calcite formation process under pertinent geological CO2 sequestration conditions. An inversion model of experimental kinetic rate data has been developped to link the precipitation rate of calcite of the independent variables and physico-chimal parameters. Using a multidimensional least squares regression method we generate a general multivariable equation of the form: dobs = G.m Where dobs is the column matrix representing the experimental precipitation rates (in the logarithm scale) and G is a matrix containing all the experimental parameter values (temperature, pCO2, activity of inhibitor and accelerators, ionic strength). The m term is also a column matrix corresponding to the value (weight) affected by each parameter and evaluated by the kinetic data inversion. Scenarios resulting from mixing of fluids in the aquifer and others enriched in CO2 show an rapid initial enhancement of the carbonate precipitation rate. However, when pCO2 and salinity decrease the calcite kinetic rate is inhibited and the rate is not ruled by simple affinity (i.e. [CO3]) laws. We observed an intermediate stage where the rate of calcite precipitation is low because of inhibiting influence of the salinity. In a final stage, the neutralisation of the fluid acidity by the rock dissolution generates a higher saturation state of the fluids that with a high carbonate ion concentration (from 0.90 to 2.5 mmol/kg) is responsible for 3 orders of magnitude increase of the calcite precipitation rate. Our results clearly identify the kinetics and thermodynamics role on the major parameters that drive the carbonate precipitation reaction.

  2. Formation of indoor nitrous acid (HONO) by light-induced NO2 heterogeneous reactions with white wall paint.

    PubMed

    Bartolomei, Vincent; Sörgel, Matthias; Gligorovski, Sasho; Alvarez, Elena Gómez; Gandolfo, Adrien; Strekowski, Rafal; Quivet, Etienne; Held, Andreas; Zetzsch, Cornelius; Wortham, Henri

    2014-01-01

    Gaseous nitrogen dioxide (NO2) represents an oxidant that is present in relatively high concentrations in various indoor settings. Remarkably increased NO2 levels up to 1.5 ppm are associated with homes using gas stoves. The heterogeneous reactions of NO2 with adsorbed water on surfaces lead to the generation of nitrous acid (HONO). Here, we present a HONO source induced by heterogeneous reactions of NO2 with selected indoor paint surfaces in the presence of light (300 nmformation of HONO is much more pronounced at elevated relative humidity. In the presence of light (5.5 W m(-2)), an increase of HONO production rate of up to 8.6·10(9) molecules cm(-2) s(-1) was observed at [NO2]=60 ppb and 50% relative humidity (RH). At higher light intensity of 10.6 (W m(-2)), the HONO production rate increased to 2.1·10(10) molecules cm(-2) s(-1). A high NO2 to HONO conversion yield of up to 84% was observed. This result strongly suggests that a light-driven process of indoor HONO production is operational. This work highlights the potential of paint surfaces to generate HONO within indoor environments by light-induced NO2 heterogeneous reactions. PMID:24723352

  3. Geologic Controls on the Growth of Petroleum Reserves

    USGS Publications Warehouse

    Fishman, Neil S.; Turner, Christine E.; Peterson, Fred; Dyman, Thaddeus S.; Cook, Troy

    2008-01-01

    The geologic characteristics of selected siliciclastic (largely sandstone) and carbonate (limestone and dolomite) reservoirs in North America (largely the continental United States) were investigated to improve our understanding of the role of geology in the growth of petroleum reserves. Reservoirs studied were deposited in (1) eolian environments (Jurassic Norphlet Formation of the Gulf Coast and Pennsylvanian-Permian Minnelusa Formation of the Powder River Basin), (2) interconnected fluvial, deltaic, and shallow marine environments (Oligocene Frio Formation of the Gulf Coast and the Pennsylvanian Morrow Formation of the Anadarko and Denver Basins), (3) deeper marine environments (Mississippian Barnett Shale of the Fort Worth Basin and Devonian-Mississippian Bakken Formation of the Williston Basin), (4) marine carbonate environments (Ordovician Ellenburger Group of the Permian Basin and Jurassic Smackover Formation of the Gulf of Mexico Basin), (5) a submarine fan environment (Permian Spraberry Formation of the Midland Basin), and (6) a fluvial environment (Paleocene-Eocene Wasatch Formation of the Uinta-Piceance Basin). The connection between an oil reservoir's production history and geology was also evaluated by studying production histories of wells in disparate reservoir categories and wells in a single formation containing two reservoir categories. This effort was undertaken to determine, in general, if different reservoir production heterogeneities could be quantified on the basis of gross geologic differences. It appears that reserve growth in existing fields is most predictable for those in which reservoir heterogeneity is low and thus production differs little between wells, probably owing to relatively homogeneous fluid flow. In fields in which reservoirs are highly heterogeneous, prediction of future growth from infill drilling is notably more difficult. In any case, success at linking heterogeneity to reserve growth depends on factors in addition to geology, such as engineering and technological advances and political or cultural or economic influences.

  4. Pore size and pore throat types in a heterogeneous dolostone reservoir, Devonian Grosmont formation, western Canada sedimentary basin

    SciTech Connect

    Luo, P.; Machel, H. G.

    1995-11-01

    The Devonian Grosmont Formation in northeastern Alberta, Canada, is a giant heavy-oil reservoir. The main reservoir rocks are dolomitized and karstified platform and ramp carbonates, and the best reservoir facies occur in the upper Grosmont (UGM) units 3 and 2. In these units, reservoir properties are highly heterogeneous. Hand specimen, thin section, UV, and SEM petrography, as well as grading scales, mercury capillary pressure curve analysis, and statistics, have been used to characterize reservoir heterogeneity. Our investigation led to a new pore size classification for carbonate reservoirs; this new classification has four pore sizes: microporosity (pore diameters <1 {mu}m), mesoporosity (pore diameters 1-1000 {mu}m), macroporosity (pore diameters 1-256 mm), and megaporosity (pore diameters >256 mm). A combination of microscopic observations and capillary pressure curve characteristics led to the recognition of four pore throat texture types on the microporosity scale, and to five types on the mesoporosity scale. Microporosity pore types include (1) intracrystal dissolution porosity, (2) pervasive intercrystal and intracrystal dissolution porosity, (3) intergranular and/or intercrystal porosity in grainstones, and (4) primary or solution microporosity in mud matrix (only in limestones). Mesoporosity pore types include (1) intercrystal porosity, (2) solution-enhanced intercrystal porosity, (3) oversized porosity, (4) intragranular solution porosity, and (5) intergranular solution porosity. Some of these types are homogeneous (e.g., non-fabric selective dissolution porosity and intercrystal primary porosity), whereas others are heterogeneous. Generally, hydrocarbon recovery efficiency is good in the homogeneous pore throat types, but poor in the heterogeneous types.

  5. Multiscale heterogeneity characterization of tidal channel, tidal delta and foreshore facies, Almond Formation outcrops, Rock Springs uplift, Wyoming

    SciTech Connect

    Schatzinger, R.A.; Tomutsa, L.

    1997-08-01

    In order to accurately predict fluid flow within a reservoir, variability in the rock properties at all scales relevant to the specific depositional environment needs to be taken into account. The present work describes rock variability at scales from hundreds of meters (facies level) to millimeters (laminae) based on outcrop studies of the Almond Formation. Tidal channel, tidal delta and foreshore facies were sampled on the eastern flank of the Rock Springs uplift, southeast of Rock Springs, Wyoming. The Almond Fm. was deposited as part of a mesotidal Upper Cretaceous transgressive systems tract within the greater Green River Basin. Bedding style, lithology, lateral extent of beds of bedsets, bed thickness, amount and distribution of depositional clay matrix, bioturbation and grain sorting provide controls on sandstone properties that may vary more than an order of magnitude within and between depositional facies in outcrops of the Almond Formation. These features can be mapped on the scale of an outcrop. The products of diagenesis such as the relative timing of carbonate cement, scale of cemented zones, continuity of cemented zones, selectively leached framework grains, lateral variability of compaction of sedimentary rock fragments, and the resultant pore structure play an equally important, although less predictable role in determining rock property heterogeneity. A knowledge of the spatial distribution of the products of diagenesis such as calcite cement or compaction is critical to modeling variation even within a single facies in the Almond Fin. because diagenesis can enhance or reduce primary (depositional) rock property heterogeneity. Application of outcrop heterogeneity models to the subsurface is greatly hindered by differences in diagenesis between the two settings. The measurements upon which this study is based were performed both on drilled outcrop plugs and on blocks.

  6. INTERNATIONAL UNION OF GEOLOGICAL SCIENCES (IUGS) Reporting Format for Subcommission on Triassic Stratigraphy (STS).

    E-print Network

    McRoberts, Christopher A.

    @online.marine.su Secretary general : G. Warrington, British Geological Survey, Kinsley Dunham Centre, Keyworth, Nottingham NG1 5GG, U.K., e-mail: gwar@wpo.nerc.ac.uk #12;2 2 Albertiana editor and Webmaster: Wolfram M

  7. INTERNATIONAL UNION OF GEOLOGICAL SCIENCES (IUGS) Reporting Format for Subcommission on Triassic Stratigraphy (STS).

    E-print Network

    McRoberts, Christopher A.

    @online.marine.su #12;2 2 Secretary general : G. Warrington, British Geological Survey, Kinsley Dunham Centre, Keyworth, Nottingham NG1 5GG, U.K., e-mail: gwar@wpo.nerc.ac.uk Past Chairman: A.Baud, Musée géologique, UNIL-BFSH 2

  8. The Enigmatic Longevity of Granular Materials on Mars: The Case for Geologically Episodic Dune Formation

    NASA Technical Reports Server (NTRS)

    Marshall, J.

    1999-01-01

    Martian sand dunes are concentrated in vast sand seas in the circumpolar belt of the planet's northern hemisphere, but they are also pervasive over the whole planet. Their occurrence is to be expected on a super-arid planetary surface subjected to boundary layer drag from a continually active atmosphere. Whilst their occurrence is to be expected, their survival is enigmatic. But the enigma only arises if the martian system is considered similar to Earth's --where sand is moved highly frequently, more or less on a seasonal basis. Experimentally it is readily demonstrated that active sand will soon wear down to small grains and eventually diminish to below the critical sand size required to sustain dune formation. According to conventional wisdom, sand moves at higher speeds on Mars than on Earth, and if it were to move as frequently as it does on Earth, then the dune-forming sand population should have long since disappeared, given the great longevity of the martian aeolian system (Sagan coined the term "kamikaze" grains to express this disappearance). No supply of sand could keep pace with this depletion, especially in light of the fact that Mars does not have very active weathering, nor significant crustal differentiation. On Earth, plate tectonics, magmatic activity, and general crustal differentiation over geological time have produced great concentrations of quartz crystals in the continental crustal masses. Not only are these quartz grains chemically and mechanically resilient, they are about the right size for being transported by either wind or water. Add to this, the geologically recent contribution of glacial grinding, and it is easy to see why there are dune field on Earth. So what are the martian dunes composed of, and how does the material survive the eons of attrition? In addition to experimental demonstrations of sand comminution in laboratory aeolian simulations, the problem can be approached from first principles. Sagan showed that by simple considerations of material strength versus mechanical work applied to the material, comminution to sub-sand size would be inevitable. Another semi-analytical approach might be taken by considering that the archetypal aeolian sand surface texture is an irregularly pitted ("frosted") surface composed of chipping hollows approximately 10 microns in diameter, 5 microns deep. Their volume = about 250 cubic microns, or about 1/25000 of the volume of a 100 micron diameter dune grain. Because a saltating grain always strikes another grain, then two surfaces are impacted. Thus each grain undergoes two impacts for every one saltation leap, when the impact statistics are considered for a closed dune system (it can be calculated that a grain can never undergo <1 impact, and never >2 per saltation leap). Hence, if we conservatively assume that there is damage to a grain each time it bounces, but with the minimum damage of only 2 microscopic craters per impact, then approximately 12,500 impacts are required to completely eliminate the grain. Of course, it would require only a fraction of this amount to reduce the grain to below sand size. A grain will make only several tens of saltation leaps on the stoss side of a dune before becoming buried on the lee slope. The dune then has to move its full length before the grain is exhumed again for abrasion. Even with this hiatus in transport, it is easy to see that terrestrial dunes need resupplying with sand in order to survive. In recent theoretical work it has been shown that martian aeolian transport may be initiated with high-speed grains, but this converts to a lower energy dynamic transport equilibrium in which a reptation population dominates grain transport (on Earth, at least half of the flux is by reptation and creep). On Mars, therefore, average grain speeds may be lower than those on Earth, or at least comparable. This would permit greater longevity for martian sands, but it would not go far enough to solve the survival problem. It may, however, explain why martian dunes are about the same size as terr

  9. Formation of fold and thrust belts on Venus due to horizontal shortening of a laterally heterogeneous lithosphere

    NASA Technical Reports Server (NTRS)

    Zuber, M. T.; Parmentier, E. M.; Neumann, G. A.

    1994-01-01

    An outstanding question relevant to understanding the tectonics of Venus is the mechanism of formation of fold and thrust belts, such as the mountain belts that surround Lakshmi Planum in western Ishtar Terra. These structures are typically long (hundreds of km) and narrow (many tens of km), and are often located at the margins of relatively high (km-scale) topographic rises. Previous studies have attempted to explain fold and thrust belts in various areas of Venus in the context of viscous and brittle wedge theory. However, while wedge theory can explain the change in elevation from the rise to the adjacent lowland, it fails to account for a fundamental aspect of the deformation, i.e., the topographic high at the edge of the rise. In this study we quantitatively explore the hypothesis that fold and thrust belt morphology on Venus can alternatively be explained by horizontal shortening of a lithosphere that is laterally heterogeneous, due either to a change in thickness of the lithosphere or the crust. Lateral heterogeneities in lithosphere structure may arise in response to thermal thinning or extensive faulting, while variations in crustal thickness may arise due to either spatially variable melting of mantle material or by horizontal shortening of the crust. In a variable thickness lithosphere or crust that is horizontally shortened, deformation will tend to localize in the vicinity of thickness heterogeneity, resulting in a higher component of dynamic topography there as compared to elsewhere in the shortening lithosphere. This mechanism may thus provide a simple explanation for the topographic high at the edge of the rise.

  10. A case of type I polar stratospheric cloud formation by heterogeneous nucleation

    NASA Technical Reports Server (NTRS)

    Pueschel, R. F.; Ferry, G. V.; Snetsinger, K. G.; Goodman, J.; Dye, J. E.; Baumgardner, D.; Gandrud, B. W.

    1992-01-01

    The NASA ER-2 aircraft flew on January 24, 1989, from Stavanger to Spitsbergen, Norway, at the 430-440 K potential temperature surface (19.2-19.8 km pressure altitude). Aerosols were sampled continuously by an optical particle counter (PMS-FSSP300) for concentration and size analyses, and during five 10-min intervals by four wire and one replicator impactor for concentration, size, composition, and phase analysis. During sampling, the air saturation of H2O with respect to ice changed from 20 to 100 percent, and of HNO3 with respect to nitric acid trihydrate (NAT) from subsaturation to supersaturation. Data from both instruments indicate a condensation of hydrochloric acid and, later, nitric acid on the background aerosol particles as the ambient temperature decreases along the flight track. This heterogeneous nucleation mechanism generates type I polar stratospheric cloud particles of 10-fold enhanced optical depth, which could play a role in stratospheric ozone depletion.

  11. Heterogeneous Reaction of NO2 on Soot Surfaces and the Effect of Soot Aging on its Reactivity Leading to HONO Formation 

    E-print Network

    Cruz Quinones, Miguel

    2011-02-22

    -1 HETEROGENEOUS REACTION OF NO 2 ON SOT SURFACES AND THE FECT OF SOT AGING ON ITS REACTIVITY LEADING TO HONO FORMATION A Thesis by MIGUEL CRUZ QUI?ONES Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 2009 Major Subject: Chemistry HETEROGENEOUS REACTION OF NO 2 ON SOT SURFACES AND THE FECT OF SOT AGING ON ITS REACTIVITY LEADING TO HONO FORMATION A Thesis by MIGUEL CRUZ QUI...

  12. Dissolution and Cave Formation in Eogenetic Limestone Aquifers by Spatial Heterogeneity in PCO2 at Water Tables

    NASA Astrophysics Data System (ADS)

    Gulley, J. D.; Martin, J. B.; Moore, P. J.; Brown, A.; Spellman, P.; Ezell, J. E.

    2014-12-01

    Dissolution processes are well-understood in limestone that has had its primary porosity occluded during burial and cementation (telogenetic limestone). Less is known about dissolution in unburied limestone with high primary permeability (eogenetic limestone). In telogenetic limestone, dissolution occurs where surface streams follow fractures that provide preferential flow paths through an impermeable aquifer matrix. Initial chemical undersaturation of surface water drives dissolution; caves form by enlargement of fractures. In contrast, eogenetic limestone's high permeability precludes surface streams. Recharge is thought to be diffuse and water-rock interaction in porous vadose zones to result in chemical equilibration of recharge prior to reaching the water table. Despite these limitations on dissolution, phreatic conduits >100 km long occur in eogenetic limestone, suggesting active dissolution in the phreatic zone. Models of dissolution and cave formation in eogenetic limestone emphasize mixing, with mixing of fresh and saline water thought to be the primary dissolution mechanism. Mixing dissolution models consider pCO2 to be homogeneously distributed within mixing waters. If this assumption is correct, mixing offers the only plausible dissolution mechanism. Here we report data from San Salvador Island, Bahamas that demonstrates pCO2 is heterogeneously, rather than homogenously, distributed. The pCO2 in wells varied from < log -2.0 to > log -1.0 atm over distances of less than 30 m. We hypothesize spatial variability in pCO2 results from spatial variability in inputs of DOC to the water table; dissolution is focused to form caves where water flows from regions of low DOC inputs to regions of high DOC inputs. Oxidation of DOC to CO2, enables water to dissolve 2.5 to 10 times more calcite than the maximum amount possible by mixing. Heterogeneous inputs of DOC to aquifers may be the dominant dissolution and cave formation mechanism in eogenetic karst aquifers.

  13. Experimental Constraints on Alkali Volatilization during Chondrule Formation: Implications for Early Solar System Heterogeneity

    NASA Astrophysics Data System (ADS)

    Ustunisik, G. K.; Ebel, D. S.; Nekvasil, H.

    2014-12-01

    The chemical variability of chondrule volatile element contents provide a wealth of information on the processes that shaped the early solar system and its compositional heterogeneity. An essential observation is that chondrule melts contain very low alkalies and other volatile elements (e.g., Cl). The reason for this depletion is the combined effects of cooling rates (10 to 1000K/h), the small size of chondrules, and their high melting temperatures (~1700 to 2100 K) resulting in extensive loss of volatiles at canonical pressures (e.g., 10-4bar). However, we observe some chondrules with significant concentrations of volatiles (Na, Cl), that differ markedly from chondrules dominated by refractory elements. Could such heterogeneity arise from loss of alkalis and Cl to a gas phase that itself later condenses, thereby yielding variations in volatile enrichments in chondrules? Does Cl enhance volatility of the alkalis to varying extents? Experiments on Cl-bearing and Cl-free melts of equivalent composition for 10 min, 4 h, and 6 h reveal systematic effects of Cl on alkali volatility. Cl-bearing melts lose 48% of initial Na2O, 66% of K2O, 96% of Cl within the first 10 minutes of degassing. Then the amount of alkali loss decreases due to the absence of Cl. Cl-free melts loses only 15% of initial Na2O and 33% K2O. After 4 hours, melts lose 1/3 of initial Na2O and 1/2 of K2O. For both systems, Na2O is more compatible in the melt relative to K2O. Therefore, the vapor given off has a K/Na ratio higher than the melt through time in spite of the much higher initial Na abundance in the melt. Enhanced vaporization of alkalis from Cl-bearing melt suggests that Na and K evaporate more readily as volatile chlorides than as monatomic gases. Cl-free initial melts with normative plagioclase of An50Ab44Or6 evolved into slightly normal zoned ones (An49Ab50Or1) while Cl-bearing initial melts normative to albitic plagioclase (An46Ab50Or4) evolved to reverse zoned ones (An54Ab45Or1). The vapor phase over Cl-bearing chondrule melts may have a bimodal character over time. The heteregeneous volatile contents of chondrules may result from quenching of melt droplets at different stages of repeated heating, chondrule fragment recycling, and recondensation of exsolved volatiles.

  14. Geologic map of the Peach Orchard Flat quadrangle, Carbon County, Wyoming, and descriptions of new stratigraphic units in the Upper Cretaceous Lance Formation and Paleocene Fort Union Formation, eastern Greater Green River Basin, Wyoming-Colorado

    USGS Publications Warehouse

    Honey, J.D.; Hettinger, R.D.

    2004-01-01

    This report provides a geologic map of the Peach Orchard Flat 7.5-minute quadrangle, located along the eastern flank of the Washakie Basin, Wyo. Geologic formations and individual coal beds were mapped at a scale of 1:24,000; surface stratigraphic sections were measured and described; and well logs were examined to determine coal correlations and thicknesses in the subsurface. In addition, four lithostratigraphic units were named: the Red Rim Member of the Upper Cretaceous Lance Formation, and the China Butte, Blue Gap, and Overland Members of the Paleocene Fort Union Formation.

  15. Spatial Heterogeneity and Imperfect Mixing in Chemical Reactions: Visualization of Density-Driven Pattern Formation

    DOE PAGESBeta

    Sobel, Sabrina G.; Hastings, Harold M.; Testa, Matthew

    2009-01-01

    Imperfect mixing is a concern in industrial processes, everyday processes (mixing paint, bread machines), and in understanding salt water-fresh water mixing in ecosystems. The effects of imperfect mixing become evident in the unstirred ferroin-catalyzed Belousov-Zhabotinsky reaction, the prototype for chemical pattern formation. Over time, waves of oxidation (high ferriin concentration, blue) propagate into a background of low ferriin concentration (red); their structure reflects in part the history of mixing in the reaction vessel. However, it may be difficult to separate mixing effects from reaction effects. We describe a simpler model system for visualizing density-driven pattern formation in an essentiallymore »unmixed chemical system: the reaction of pale yellow Fe 3 + with colorless SCN ? to form the blood-red Fe ( SCN ) 2 + complex ion in aqueous solution. Careful addition of one drop of Fe ( NO 3 ) 3 to KSCN yields striped patterns after several minutes. The patterns appear reminiscent of Rayleigh-Taylor instabilities and convection rolls, arguing that pattern formation is caused by density-driven mixing. « less

  16. Modeling the formation of polar stratospheric clouds with allowance for kinetic and heterogeneous processes

    NASA Astrophysics Data System (ADS)

    Aloyan, A. E.; Yermakov, A. N.; Arutyunyan, V. O.

    2015-05-01

    A new mathematical model of global transport of multicomponent gaseous admixtures and aerosols in the atmosphere and the formation of polar stratospheric clouds (PSC) in both hemispheres has been constructed. Two types of PSCs are considered: type Ia, nitric acid trihydrate (NAT), and type Ib, supercooled ternary solutions of H2SO4/HNO3/H2O (STS). New equations are used to describe the variation in gas- and condensed-phase components on the basis of their thermodynamic properties. The formation of PSCs is coupled with sulfate aerosols generated in the upper troposphere and lower stratosphere, and with chemical and kinetic transformation processes (photochemistry, nucleation, condensation/evaporation, and coagulation). Using this coupled model, numerical experiments were performed to reproduce the spatial and temporal variability of PSCs in winter in both hemispheres. First, the formation of primary sulfate aerosols in the atmosphere is considered and then these aerosols are incorporated to the PSC model. The results of the numerical experiments are analyzed.

  17. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been made. Petrophysical and engineering property characterization has been essentially completed. Porosity and permeability data at Appleton and Vocation Fields have been analyzed, and well performance analysis has been conducted. Data integration is up to date, in that, the geological, geophysical, petrophysical and engineering data collected to date for Appleton and Vocation Fields have been compiled into a fieldwide digital database. 3-D geologic modeling of the structures and reservoirs at Appleton and Vocation Fields has been completed. The model represents an integration of geological, petrophysical and seismic data. 3-D reservoir simulation of the reservoirs at Appleton and Vocation Fields has been completed. The 3-D geologic model served as the framework for the simulations. A technology workshop on reservoir characterization and modeling at Appleton and Vocation Fields was conducted to transfer the results of the project to the petroleum industry.

  18. Simulating Geologic Co-sequestration of Carbon Dioxide and Hydrogen Sulfide in a Basalt Formation

    SciTech Connect

    Bacon, Diana H.; Ramanathan, Ramya; Schaef, Herbert T.; McGrail, B. Peter

    2014-01-15

    Co-sequestered CO2 with H2S impurities could affect geologic storage, causing changes in pH and oxidation state that affect mineral dissolution and precipitation reactions and the mobility of metals present in the reservoir rocks. We have developed a variable component, non-isothermal simulator, STOMP-COMP (Water, Multiple Components, Salt and Energy), which simulates multiphase flow gas mixtures in deep saline reservoirs, and the resulting reactions with reservoir minerals. We use this simulator to model the co-injection of CO2 and H2S into brecciated basalt flow top. A 1000 metric ton injection of these supercritical fluids, with 99% CO2 and 1% H2S, is sequestered rapidly by solubility and mineral trapping. CO2 is trapped mainly as calcite within a few decades and H2S is trapped as pyrite within several years.

  19. Self-aligned hemispherical formation of microlenses from colloidal droplets on heterogeneous surfaces

    NASA Astrophysics Data System (ADS)

    Chen, Chin-Tai; Tseng, Zhao-Fu; Chiu, Ching-Long; Hsu, Chung-Yi; Chuang, Chun-Te

    2009-02-01

    This paper proposes a drop-on-demand (DOD) theory and scheme for constructing hemispherical refractive microlenses onto underlying heterogeneous (laterally structured) surfaces that consist of hydrophilic s-domains and hydrophobic p-domains. In theory, the drops would self-align themselves into the s-domains by repelling the p-domains due to surface tension, precisely determining the placement though disobeying the Young-Laplace equation. Using a droplet generator (inkjet printhead), in our experiments, evaporative polyurethane (PU) drops well fitted their footprints (base radii) onto the s-domains with a radius of 100 µm surrounded by the p-domains of Teflon, where the photoresist AZ4620 was used for lifting off the corresponding domains of Teflon. As a result, plano-convex shapes with spherical curvatures were fabricated in an array (spacing L ~ 100 µm) with base (footprint) radius (Rb) ~ 95 µm and curvature radius (Rc) ~ 122 µm. Thus, both the theoretical and experimental results agreed well in a hemispherical shape (deviation < 5%) with the contact angle ? ~ 51°. Further, such an angle could be tunable with ?? over 20° simply by varying drop volume. In addition, one interesting and significant finding, for two (and more) overflow drops (Rb > Rs + L/2 = 150 µm, in excess of volume), indicates that more complex shapes than spherical ones (such as dumbbell and cross-like) can also be constructed by bridging the drops. Compared to those previous methods using photolithographic techniques, the present method is potentially appropriate for the varying radius and complex placement of array patterns.

  20. Geology and ground-water resources of the Cockfield Formation in western Tennessee

    USGS Publications Warehouse

    Parks, W.S.; Carmichael, J.K.

    1990-01-01

    The Cockfield Formation of the Claiborne Group of Tertiary age underlies approximately 4,000 sq mi in western Tennessee. The formation consists primarily of lenticular beds of very fine to coarse sand, silt, clay, and lignite. The Cockfield Formation has been extensively eroded, and the original thickness is preserved only in a few areas where the formation ranges from 235 to 270 ft in thickness. Recharge to the Cockfield aquifer is from precipitation on sparse outcrops or by downward infiltration of water from the overlying fluvial deposits of Tertiary and Quaternary age and alluvium of Quaternary age or, where present, the overlying Jackson Formation of Tertiary age. Data from two observation wells indicate that water levels have risen at average rates of about 0.5 and 0.7 ft/year during the period 1980-85. Water from the Cockfield aquifer is a calcium bicarbonate type that contains low concentrations of most major constituents, and generally is suitable for most uses. Dissolved-solids concentrations range from 44 to 218 mg/L. Data from two aquifer tests indicate transmissivities of 2,500 and 6 ,000 sq ft/day and storage coefficients of 0.0003 and 0.0007, respectively. The Cockfield aquifer presently provides small to moderate quantities of water for several public and industrial water supplies and small quantities to numerous domestic and farm wells. Withdrawals for public and industrial supplies in 1983 averaged about 3.3 million gal/day. (USGS)

  1. Secondary Organic Aerosol Formation From the Heterogeneous Chemistry of Isoprene-Derived Epoxides: Implications for Air Quality, Climate and Public Health

    E-print Network

    Turro, Nicholas J.

    Secondary Organic Aerosol Formation From the Heterogeneous Chemistry of Isoprene- Derived Epoxides, the largest mass fraction of PM2.5 is organic, and is mostly dominated by secondary organic aerosol (SOA underestimate observations. By combining organic synthesis, computational calculations, mass spectrometry, smog

  2. Geologic structure and altitude of the top of the Minnelusa Formation, northeastern Black Hills, South Dakota

    USGS Publications Warehouse

    Peter, Kathy D.; Kyllonen, David P.; Mills, Kathy R.

    1988-01-01

    This map shows the altitude of the top of the Permian--and Pennsylvanian age Minnelusa Formation, the deepest aquifer in the northeastern Black Hills for which there is sufficient data available to construct a structural map. The Minnelusa Formation outcrops in the western part of the map area and is more than 3 ,600 ft below land surface in the northeastern corner of the area. The formation consists of interbedded sandstone, sandy dolomite and limestone, shale, siltstone, gypsum, and anhydrite. The upper beds are an aquifer and the lower beds are a confining or semi-confining unit. Small anticlines and synclines parallel the Minnelusa outcrop. Domal structures and peaks in the study area are the result of Tertiary-age intrusions. (USGS)

  3. Geological Sequestration of CO2 by Hydrous Carbonate Formation with Reclaimed Slag

    SciTech Connect

    Von L. Richards; Kent Peaslee; Jeffrey Smith

    2008-02-06

    The concept of this project is to develop a process that improves the kinetics of the hydrous carbonate formation reaction enabling steelmakers to directly remove CO2 from their furnace exhaust gas. It is proposed to bring the furnace exhaust stream containing CO2 in contact with reclaimed steelmaking slag in a reactor that has an environment near the unit activity of water resulting in the production of carbonates. The CO2 emissions from the plant would be reduced by the amount sequestered in the formation of carbonates. The main raw materials for the process are furnace exhaust gases and specially prepared slag.

  4. Inventory of Shale Formations in the US, Including Geologic, Hydrological, and Mechanical Characteristics

    SciTech Connect

    Dobson, Patrick; Houseworth, James

    2013-11-22

    The objective of this report is to build upon previous compilations of shale formations within many of the major sedimentary basins in the US by developing GIS data delineating isopach and structural depth maps for many of these units. These data are being incorporated into the LANL digital GIS database being developed for determining host rock distribution and depth/thickness parameters consistent with repository design. Methods were developed to assess hydrological and geomechanical properties and conditions for shale formations based on sonic velocity measurements.

  5. Thermal Decomposition of Gaseous Ammonium Nitrate at Low Pressure: Kinetic Modeling of Product Formation and Heterogeneous Decomposition of Nitric Acid

    NASA Astrophysics Data System (ADS)

    Park, J.; Lin, M. C.

    2009-10-01

    The thermal decomposition of ammonium nitrate, NH4NO3 (AN), in the gas phase has been studied at 423-56 K by pyrolysis/mass spectrometry under low-pressure conditions using a Saalfeld reactor coated with boric acid. The sublimation of NH4NO3 at 423 K was proposed to produce equal amounts of NH3 and HNO3, followed by the decomposition reaction of HNO3, HNO3 + M ? OH + NO2 + M (where M = third-body and reactor surface). The absolute yields of N2, N2O, H2O, and NH3, which can be unambiguously measured and quantitatively calibrated under a constant pressure at 5-6.2 torr He are kinetically modeled using the detailed [H,N,O]-mechanism established earlier for the simulation of NH3-NO2 (Park, J.; Lin, M. C. Technologies and Combustion for a Clean Environment. Proc. 4th Int. Conf. 1997, 34-1, 1-5) and ADN decomposition reactions (Park, J.; Chakraborty, D.; Lin, M. C. Proc. Combust. Inst. 1998, 27, 2351-2357). Since the homogeneous decomposition reaction of HNO3 itself was found to be too slow to account for the consumption of reactants and the formation of products, we also introduced the heterogeneous decomposition of HNO3 in our kinetic modeling. The heterogeneous decomposition rate of HNO3, HNO3 + (B2O3/SiO2) ? OH + NO2 + (B2O3/SiO2), was determined by varying its rate to match the modeled result to the measured concentrations of NH3 and H2O; the rate could be represented by k2b = 7.91 × 107 exp(-12 600/T) s-1, which appears to be consistent with those reported by Johnston and co-workers (Johnston, H. S.; Foering, L.; Tao, Y.-S.; Messerly, G. H. J. Am. Chem. Soc. 1951, 73, 2319-2321) for HNO3 decomposition on glass reactors at higher temperatures. Notably, the concentration profiles of all species measured could be satisfactorily predicted by the existing [H,N,O]-mechanism with the heterogeneous initiation process.

  6. Evaluation of the geological relationships to gas hydrate formation and stability

    SciTech Connect

    Krason, J.; Finley, P.

    1988-01-01

    The summaries of regional basin analyses document that potentially economic accumulations of gas hydrates can be formed in both active and passive margin settings. The principal requirement for gas hydrate formation in either setting is abundant methane. Passive margin sediments with high sedimentation rates and sufficient sedimentary organic carbon can generate large quantities of biogenic methane for hydrate formation. Similarly, active margin locations near a terrigenous sediment source can also have high methane generation potential due to rapid burial of adequate amounts of sedimentary organic matter. Many active margins with evidence of gas hydrate presence correspond to areas subject to upwelling. Upwelling currents can enhance methane generation by increasing primary productivity and thus sedimentary organic carbon. Structural deformation of the marginal sediments at both active and passive sites can enhance gas hydrate formation by providing pathways for migration of both biogenic and thermogenic gas to the shallow gas hydrate stability zone. Additionally, conventional hydrocarbon traps may initially concentrate sufficient amounts of hydrocarbons for subsequent gas hydrate formation.

  7. Geological formation - drill string dynamic interaction finite-element program (GEODYN). Phase 1. Theoretical description

    SciTech Connect

    Baird, J.A.; Apostal, M.C.; Rotelli, R.L. Jr.; Tinianow, M.A.; Wormley, D.N.

    1984-06-01

    The Theoretical Description for the GEODYN interactive finite-element computer program is presented. The program is capable of performing the analysis of the three-dimensional transient dynamic response of a Polycrystalline Diamond Compact Bit-Bit Sub arising from the intermittent contact of the bit with the downhole rock formations. The program accommodates nonlinear, time-dependent, loading and boundary conditions.

  8. Phase 1 user instruction manual. A geological formation - drill string dynamic interaction finite element program (GEODYN)

    SciTech Connect

    Tinianow, M.A.; Rotelli, R.L. Jr.; Baird, J.A.

    1984-06-01

    User instructions for the GEODYN Interactive Finite Element Computer Program are presented. The program is capable of performing the analysis of the three-dimensional transient dynamic response of a Polycrystalline Diamond Compact Bit - Bit Sub arising from the intermittent contact of the bit with the downhole rock formations. The program accommodates non-linear, time dependent, loading and boundary conditions.

  9. Leveraging Regional Exploration to Develop Geologic Framework for CO2 Storage in Deep Formations in Midwestern United States

    SciTech Connect

    Neeraj Gupta

    2009-09-30

    Obtaining subsurface data for developing a regional framework for geologic storage of CO{sub 2} can require drilling and characterization in a large number of deep wells, especially in areas with limited pre-existing data. One approach for achieving this objective, without the prohibitive costs of drilling costly standalone test wells, is to collaborate with the oil and gas drilling efforts in a piggyback approach that can provide substantial cost savings and help fill data gaps in areas that may not otherwise get characterized. This leveraging with oil/gas drilling also mitigates some of the risk involved in standalone wells. This collaborative approach has been used for characterizing in a number of locations in the midwestern USA between 2005 and 2009 with funding from U.S. Department of Energy's National Energy Technology Laboratory (DOE award: DE-FC26-05NT42434) and in-kind contributions from a number of oil and gas operators. The results are presented in this final technical report. In addition to data collected under current award, selected data from related projects such as the Midwestern Regional Carbon Sequestration Partnership (MRCSP), the Ohio River Valley CO{sub 2} storage project at and near the Mountaineer Plant, and the drilling of the Ohio Stratigraphic well in Eastern Ohio are discussed and used in the report. Data from this effort are also being incorporated into the MRCSP geologic mapping. The project activities were organized into tracking and evaluation of characterization opportunities; participation in the incremental drilling, basic and advanced logging in selected wells; and data analysis and reporting. Although a large number of opportunities were identified and evaluated, only a small subset was carried into the field stage. Typical selection factors included reaching an acceptable agreement with the operator, drilling and logging risks, and extent of pre-existing data near the candidate wells. The region of study is primarily along the Ohio River Valley corridor in the Appalachian Basin, which underlies large concentrations of CO{sub 2} emission sources. In addition, some wells in the Michigan basin are included. Assessment of the geologic and petrophysical properties of zones of interest has been conducted. Although a large number of formations have been evaluated across the geologic column, the primary focus has been on evaluating the Cambrian sandstones (Mt. Simon, Rose Run, Kerbel) and carbonates layers (Knox Dolomite) as well as on the Silurian-Devonian carbonates (Bass Island, Salina) and sandstones (Clinton, Oriskany, Berea). Factors controlling the development of porosity and permeability, such as the depositional setting have been explored. In northern Michigan the Bass Islands Dolomite appears to have favorable reservoir development. In west central Michigan the St. Peter sandstone exhibits excellent porosity in the Hart and Feuring well and looks promising. In Southeastern Kentucky in the Appalachian Basin, the Batten and Baird well provided valuable data on sequestration potential in organic shales through adsorption. In central and eastern Ohio and western West Virginia, the majority of the wells provided an insight to the complex geologic framework of the relatively little known Precambrian through Silurian potential injection targets. Although valuable data was acquired and a number of critical data gaps were filled through this effort, there are still many challenges ahead and questions that need answered. The lateral extent to which favorable potential injection conditions exist in most reservoirs is still generally uncertain. The prolongation of the characterization of regional geologic framework through partnership would continue to build confidence and greatly benefit the overall CO{sub 2} sequestration effort.

  10. Geology and hydrocarbon potential of Dawson Bay Formation carbonate unit (Middle Devonian), Williston basin, North Dakota

    SciTech Connect

    Pound, W.

    1988-07-01

    The Middle Devonian Dawson Bay Formation carbonate unit is present in the subsurface of North Dakota except where truncated by postdepositional erosion. The carbonate unit thickens from the erosional limit to a maximum thickness of 47.5 m (156 ft) in Renville County and reaches a maximum depth of 3798 m (12,460 ft) below the surface in McKenzie County. In North Dakota, a submarine hardground separates the carbonate unit from the underlying second red bed member of the Dawson Bay Formation. The upper contact with the Souris River Formation is conformable except in those areas where the Dawson Bay Formation was exposed to subaerial erosion prior to deposition of the Souris River sediments. The Dawson Bay carbonate unit is predominantly dolomitic and fossiliferous limestone or fossiliferous dolostone. The carbonate unit can be subdivided into five lithofacies on the basis of characteristic fossil fauna, flora, and other lithologic features. Lithofacies analysis of the Dawson Bay carbonates suggests a shallowing-upward succession of depositional environments and associated energy zones as follows: shallow epeiric sea (very low energy), stromatoporoid biostrome/bioherm (low energy), very shallow epeiric sea (very low energy), restricted shallow epeiric sea (extremely low energy), and shallow epeiric sea shoreline (variable energy). Eogenetic diagenesis includes color-mottling, dolomitization of micrite to microcrystalline dolomite with penecontemporaneous anhydrite replacement of cryptalgal mudstones and boundstones, cementation by sparry calcite, and vuggy porosity development. Mesogenetic diagenesis includes formation of mosaic dolomites, cementation by blocky equant calcite, neomorphism, pressure-solution, fracturing, halite cementation, and hydrocarbon emplacement.

  11. Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges

    SciTech Connect

    Pruess, Karsten

    2006-03-08

    Rising atmospheric concentrations of CO2, and their role inglobal warming, have prompted efforts to reduce emissions of CO2 fromburning of fossil fuels. An attractive mitigation option underconsideration in many countries is the injection of CO2 from stationarysources, such as fossil-fueled power plants, into deep, stable geologicformations, where it would be stored and kept out of the atmosphere fortime periods of hundreds to thousands of years or more. Potentialgeologic storage reservoirs include depleted or depleting oil and gasreservoirs, unmineable coal seams, and saline formations. While oil andgas reservoirs may provide some attractive early targets for CO2 storage,estimates for geographic regions worldwide have suggested that onlysaline formations would provide sufficient storage capacity tosubstantially impact atmospheric releases. This paper will focus on CO2storage in saline formations.Injection of CO2 into a saline aquifer willgive rise to immiscible displacement of brine by the advancing CO2. Thelower viscosity of CO2 relative to aqueous fluids provides a potentialfor hydrodynamic instabilities during the displacement process. Attypical subsurface conditions of temperature and pressure, CO2 is lessdense than aqueous fluids and is subject to upward buoyancy force inenvironments where pressures are controlled by an ambient aqueous phase.Thus CO2 would tend to rise towards the top of a permeable formation andaccumulate beneath the caprock. Some CO2 will also dissolve in theaqueous phase, while the CO2-rich phase may dissolve some formationwaters, which would tend to dry out the vicinity of the injection wells.CO2 will make formation waters more acidic, and will induce chemicalrections that may precipitate and dissolve mineral phases (Xu et al.,2004). As a consequence of CO2 injection, significant pressurization offormation fluids would occur over large areas. These pressurizationeffects will change effective stresses, and may cause movement alongfaults with associated seismicity and increases in permeability thatcould lead to leakage from the storage reservoir (Rutqvist and Tsang,2005).

  12. The geology and mechanics of formation of the Fort Rock Dome, Yavapai County, Arizona

    USGS Publications Warehouse

    Fuis, Gary S.

    1996-01-01

    The Fort Rock Dome, a craterlike structure in northern Arizona, is the erosional product of a circular domal uplift associated with a Precambrian shear zone exposed within the crater and with Tertiary volcanism. A section of Precambrian to Quaternary rocks is described, and two Tertiary units, the Crater Pasture Formation and the Fort Rock Creek Rhyodacite, are named. A mathematical model of the doming process is developed that is consistent with the history of the Fort Rock Dome.

  13. The geology of Svalbard: structural, stratigraphic and geomorphic response to the formation of two passive margins

    NASA Astrophysics Data System (ADS)

    Osmundsen, P. T.; Braathen, A.; Maher, H.

    2012-04-01

    Svalbard is located at the junction of the North Atlantic and Arctic margins, preserves an onshore structural and stratigraphic record that spans from the Devonian to the Cenozoic and records several phases of extension characterized by different tectonic transport vectors. Contractional events such as the Devonian, so-called 'Svalbardian' fold phase and the formation of an Early Cenozoic fold and thrust belt have locally modified the evidence for extension and basin formation. However, several generations of extensional structures and associated, tectonically controlled basins are displayed in world-class exposures at different locations in the archipelago. At present, we focus on the following onshore features related to extension and margin formation: 1. Late-post orogenic extension: An extensional detachment and metamorphic core complex was recently identified by us in northwestern Spitsbergen, involving re-interpretation of tectonic contacts interpreted previously as thrusts. The undulating extensional detachment appears to have controlled 'Old Red' basin formation from the Early into the Late Devonian. The core complex evolved into a N-S trending anticline with flanks that eventually became the locus of strike-slip and normal faulting. Some of these faults were demonstrably reactivated, and we propose that the Devonian structural template became important in controlling the location of later rift structures that developed from the Carboniferous onwards. 2. Carboniferous rifting: Normal faulting controlled sedimentation in Carboniferous basins including an up to 2 km deep, coastal/marine half-graben with mixed siliclastic, carbonate and evaporite fill exposed in Central Spitsbergen. The Billefjorden Fault zone (BFZ) reactivates an older, N-S trending Devonian reverse fault, and coarse siliclastic debris was transported into the basin along relay ramps that developed between the normally reactivated strands of the BFZ. Monoclinal folds, interpreted previously as Tertiary compressional features, were recently re-interpreted by two of the present authors as extensional fault-growth monoclines, similar to structures described by others from the Gulf of Suez. 3. Late Triassic normal faulting: Spectacular outcrops of syntectonic half-graben basins occur in the lower parts of the Late Triassic Deltaic DeGeerdal formation on Edge Island. The intricate architecture of sandbodies revealed by the half-graben basins can be used to decipher in detail the relationships between accommodation and sediment supply. The half-graben reveal several periods of hangingwall-directed progradation of sandy units over prodelta shales, catastrophic deposition of massive massflow sandstone wedges and the subsequent burial of these under marine shales or channel sandstone units. 4. Differential uplift, incision and landscape formation. Northwards incision of stratigraphy due to differential uplift in the Cretaceous, incision of widespread geomorphic surfaces into Palaeogene strata and the uplift of these to a 1000 metres altitude show that significant vertical movements accompanied the evolution of the margins. Pronounced variations in landscape across the archipelago and even a quaternary volcano situated on a neotectonic fault-line attests further to a large research potential with respect to the onshore response to margin formation in the Arctic and Northernmost North Atlantic.

  14. Formation of flower structures in a geological layer at a strike-slip displacement in the basement

    NASA Astrophysics Data System (ADS)

    Stefanov, Yu. P.; Bakeev, R. A.

    2015-07-01

    Formation of dislocations in a geological layer at a strike-slip displacement in its basement is studied by three-dimensional (3D) numerical modeling. It is shown that the pattern of strain localization is determined by the initial stress state or thickness of the deformed layer as well as by the Poisson ratio and strength of the medium. Three types of fracture zones are observed. Shear bands of the first type are dominated by the propeller-like surfaces of Riedel R-shears, which merge into a single main fault with feathering structures. In the second type of dislocation zones, the primary role is played by the surfaces oriented at an angle of ˜40° to the shear axis in the horizontal projections. After reaching the free surface, these discontinuities are cut by a V-shaped fault. In this case, the pattern of dislocations most closely corresponds to the flower structures. The third type is a trough, which may accommodate the formation of yet another strain localization zone along its axial part—a vertical fault.

  15. Comparison of formation and fluid-column logs in a heterogeneous basalt aquifer.

    PubMed

    Paillet, F L; Williams, J H; Oki, D S; Knutson, K D

    2002-01-01

    Deep observation boreholes in the vicinity of active production wells in Honolulu, Hawaii, exhibit the anomalous condition that fluid-column electrical conductivity logs and apparent profiles of pore-water electrical conductivity derived from induction conductivity logs are nearly identical if a formation factor of 12.5 is assumed. This condition is documented in three boreholes where fluid-column logs clearly indicate the presence of strong borehole flow induced by withdrawal from partially penetrating water-supply wells. This result appears to contradict the basic principles of conductivity-log interpretation. Flow conditions in one of these boreholes was investigated in detail by obtaining flow profiles under two water production conditions using the electromagnetic flowmeter. The flow-log interpretation demonstrates that the fluid-column log resembles the induction log because the amount of inflow to the borehole increases systematically upward through the transition zone between deeper salt water and shallower fresh water. This condition allows the properties of the fluid column to approximate the properties of water entering the borehole as soon as the upflow stream encounters that producing zone. Because this condition occurs in all three boreholes investigated, the similarity of induction and fluid-column logs is probably not a coincidence, and may relate to aquifer response under the influence of pumping from production wells. PMID:12425345

  16. Geology of the BK9 kimberlite (Damtshaa, Botswana): implications for the formation of dark volcaniclastic kimberlite

    NASA Astrophysics Data System (ADS)

    Buse, B.; Sparks, R. S. J.; Field, M.; Schumacher, J. C.; Chisi, K.; Tlhaodi, T.

    2011-10-01

    The BK9 kimberlite consists of three overlapping pipes. It contains two dark varieties of massive volcaniclastic kimberlite, informally termed dark volcaniclastic kimberlite (DVK). DVK(ns) is present in the north and south pipes and is interbedded with lenses of basalt breccia at the margins of the pipes. DVK(c) is present within the central pipe where it is overlain by a sequence of basalt breccias with interbedded volcanogenic sediments. The features observed within the DVK units of the BK9 kimberlite provide strong evidence for gas fluidisation of the accumulating pyroclastic material. These include the massive interior of the pipes, marginal epiclastic units, well-dispersed country-rock xenoliths and small-scale heterogeneities in lithic clast abundance. The upper portions of the central pipe provide a record of the transition from pyroclastic eruption and infill to passive epiclastic infilling of the crater, after the eruption has ceased. The wall-rock of the BK9 kimberlite dips inwards and is interpreted as post pipe-fill subsidence of the adjacent country rock. The two DVK units contain interstitial, silt-sized pyroclasts. The DVK(ns) has a higher fraction of former melt and displays evidence of incipient welding, as a result of differences in eruption dynamics. These units demonstrate that whilst DVK is comparable in many respects to MVK and forms part of a spectrum of volcaniclastic rocks formed by fluidisation, it differs in frequently containing silt-sized particles and including agglutinated and welded varieties with a high melt fraction. The DVK varieties, studied here, also have a distinctive hydrothermal assemblage, resulting from the abundance of low-silica accidental lithic clasts. Both the hydrothermal alteration and the abundance of silt-sized particles contribute to the DVKs distinctive dark colour.

  17. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2003-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling that utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 3 of the project has been reservoir characterization, 3-D modeling, testing of the geologic-engineering model, and technology transfer. This effort has included six tasks: (1) the study of seismic attributes, (2) petrophysical characterization, (3) data integration, (4) the building of the geologic-engineering model, (5) the testing of the geologic-engineering model and (6) technology transfer. This work was scheduled for completion in Year 3. Progress on the project is as follows: geoscientific reservoir characterization is completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been completed. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been made. Petrophysical and engineering property characterization has been completed. Porosity and permeability data at Appleton and Vocation Fields have been analyzed, and well performance analysis has been conducted. Data integration is up to date, in that, the geological, geophysical, petrophysical and engineering data collected to date for Appleton and Vocation Fields have been compiled into a fieldwide digital database. 3-D geologic modeling of the structures and reservoirs at Appleton and Vocation Fields has been completed. The models represent an integration of geological, petrophysical and seismic data. 3-D reservoir simulation of the reservoirs at Appleton and Vocation Fields has been completed. The 3-D geologic models served as the framework for the simulations. The geologic-engineering models of the Appleton and Vocation Field reservoirs have been developed. These models are being tested. The geophysical interpretation for the paleotopographic feature being tested has been made, and the study of the data resulting from drilling of a well on this paleohigh is in progress. Numerous presentations on reservoir characterization and modeling at Appleton and Vocation Fields have been made at professional meetings and conferences and a short course on microbial reservoir characterization and modeling based on these fields has been prepared.

  18. Reservoir heterogeneity and hydrocarbon production in mixed dolomitic-clastic sequence: Escandalosa Formation, Barinas-Apure basin, southwestern Venezuela

    SciTech Connect

    Escalona, N.; Abud, J.

    1989-03-01

    Widespread dedolomitization and differential leaching occur in the Turonian O Member of the Escandalosa Formation, Barinas-Apure basin. Within this dolostone-dominated succession, calcite was developed through a dedolomitization process occurring in deeply buried dolomitized lime sediments previously deposited on a carbonate platform as well as dedolomitization on the associated glauconitic-quartzose sandstones of small-scale channels that scoured the platform. The dolomitized intervals have a strata-bound nature, and their original fabric is totally obliterated. The dolomitization process generated a sucrose-textured mosaic of saddle dolomite. Initial dolomite was of the scattered type, but progressive replacement of the host produced a mosaic dolostone with both idiotopic and xenotopic textures. A general increase occurred in the iron and manganese content, and goethite was exsolved from the curved rhombs of saddle dolomite. Calcite usually postdates dolomitization, except in the highly fossiliferous packstones; calcite veins develop in both dolostones and limestones. Leaching is restricted essentially to glauconitic sandstones where calcite and some clay have been leached. This has produced very low intercrystalline porosity within the dolostones and partially dissolved, corroded and floating grains with oversized pores in the sandstones. These sandy intervals exhibit maximum potential for hydrocarbon storage, due to contrasting diagenetic influence associated with reservoir heterogeneity.

  19. Geology and taphonomy of the base of the Taquaral Member, Irati Formation (Permian, Paraná Basin), Brazil

    NASA Astrophysics Data System (ADS)

    Chahud, Artur; Petri, Setembrino

    2015-09-01

    The taphonomy of Early Permian vertebrates from a sandy facies at the base of the Taquaral Member, Irati Formation, was surveyed in order to acquire data for the interpretation of the sedimentary processes and paleoenvironment of deposition. Six outcrops from the Rio Claro municipality and surrounding areas, from the Brazilian State of São Paulo, were investigated. The vertebrate groups are Chondrichthyes (Xenacanthiformes, Ctenacanthiformes and Petalodontiformes), Osteichthyes (Actinopterygii and Sarcopterygii) and Tetrapodomorpha. They occur as loose teeth, scales, spines and bone remains. The sandy facies is characterized by fining upward deposition. The coarser sandstone immediately above the underlying Tatuí Formation is rich in Chondrichthyes. However, the fine sandstone above, immediately beneath the silty shale facies, is devoid of Chondrichthyes, though Osteichthyes scales, teeth and bones were present. The taphonomy is important for inferring sedimentary processes and then the paleoenvironments. The poor sorting of the sandstone and the presence of fossils that are mostly abraded or worn are indicative of a high energy environment. In contrast, the presence of fossils in a good state of preservation, some without abrasion and breakages are indicative of only limited transport. Differences of fossil spatial density, numbers of specimens and taxa may be explained by the dynamics of deposition, from details of the palaeoenvironment can be obtained.

  20. Using the NO2/NOx Ratio to Understand the Spatial Heterogeneity of Secondary Pollutant Formation Capacity in Urban Atmospheres

    NASA Astrophysics Data System (ADS)

    Rao, M.; George, L. A.

    2014-12-01

    Urban atmospheres are chemically reactive environments in which anthropogenic emissions can react with natural and anthropogenic components, on time scales of seconds to days, to increase the oxidative potential of the urban atmosphere and to create secondary air pollutants. The oxides of nitrogen (NOx = NO + NO2) are generated by combustion activities, including power plants and vehicles. Tailpipe emissions of NOx contain 10-20% NO2, and 90-80% NO. NO can be oxidized to NO2 by O3, HO2 and RO2species. The latter oxidants can be produced through the photo-oxidation of VOCs. It is likely then that oxidative capacity within a city is spatially heterogeneous since the distribution of anthropogenic (NOx, VOCs) and biogenic (VOCs) emissions varies spatially within the city. The spatial heterogeneity in local oxidative capacity of the urban atmosphere has seldom been measured or modeled at the fine spatial scale of ~250m. In summer 2013 we measured NO and NO2 using passive samplers over two weeks at 144 sites in the Portland Metro area. We used the ratio of NO2 to NOx as an indicator of the local atmospheric oxidative potential. We found the measured percentage of NO2 in NOx ranged from a minimum of 20% to a maximum of 76%, with an average value of 54% (std dev = 12%). The measured NO2/NOx ratio was statistically significantly correlated with both freeways and tree canopy within 250m (r = -0.25 and 0.31 respectively), showing a decreasing fraction of NO2 with increasing length of freeway and an increasing fraction of NO2in areas with greater tree cover, as expected. We will use the NO2 measurements to allocate county-level emissions to the spatial scale of ~250m for the Portland Metro area. Using WRF-Chem, we will then model the urban chemistry at this fine spatial scale, and compare the modeled NO to measured NO. Comparing the modeled and measured NO values will serve a dual purpose: it will help validate the fine spatial-scale WRF-Chem model for Portland, and it will provide an insight into the effectiveness of using the NO2/NOx ratio as an indicator of the potential for urban secondary pollutant formation.

  1. 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.

  2. Thermal-transport properties of Cenozoic and Mesozoic geological formations in the Northeast German Basin

    NASA Astrophysics Data System (ADS)

    Fuchs, Sven; Förster, Andrea

    2010-05-01

    Thermal properties of sedimentary formations are first-order controls on the thermal structure of basins. In order to overcome the limiting factor of the availability of drill core samples along the borehole profile and provide continuous thermal-conductivity profiles, standard petrophysical wireline logs and high-precision temperature logs can be used. As part of this approach, thermal conductivity was measured in the laboratory on Mesozoic sandstones from eight wells (predominantly geothermal boreholes) of the Northeast German Basin (NEGB). The measurements were made on drill core using the optical scanning method. Bulk thermal conductivities of sandstones, corrected for in situ thermal conditions, range between 2.1 and 3.8 W/m/K. In general, the Mesozoic sandstones show a large effective porosity typically ranging between 16 % and 30 %. Matrix thermal conductivity ranges from 3.4 to 7.4 W/m/K. The higher values are a reflection of large quartz content in some of the sandstones. Based on the in situ thermal conductivity and corresponding interval temperature gradient, obtained from high-precision temperature logs measured under thermal borehole equilibrium, interval heat-flow values were computed for two borehole locations in the Middle Buntsandstein section of the Stralsund area, at a depth between 1405 and 1521 m. The heat flow at that depth averages to 74 mW/m2 (Gt Ss 1/85 borehole) and 78 mW/m2 (Gt Ss 2/85 borehole), which is in good correspondence with previously reported heat-flow values for the NEGB. Based on the interval heat flow and a temperature gradient log, thermal conductivity was indirectly calculated for those parts of the section lacking measured laboratory values. Thus the Cenozoic and Mesozoic section of the Stralsund area, near the northern basin margin, show formation thermal conductivities between 1.5 and 3.8 W/m/K. Further work has to verify whether these values also qualify for other locations in the NEGB.

  3. Evaluation of the geological relationships to gas hydrate formation and stability

    SciTech Connect

    Not Available

    1985-01-01

    During the reported year we have enhanced our knowledge on and gained considerable experience in assessment of the gas hydrate resources in the offshore environments. Specifically, we have learned and gained experience in the following: Efficiently locating data sources, including published literature and unpublished information. We have established personal communication extremely critical in data accessability and acquisition. We have updated information pertinent to gas hydrate knowledge, also based on thorough study and evaluation of most Russian literature and additional publications in languages other than English. Besides critical evaluation of widely spread literature, in many cases our reports include previously unpublished information (e.g. BSRs from the Gulf of Mexico). The assessment of the gas resources potential associated with the gas hydrates, although in most cases at a low level of confidence, appears also very encouraging for further, more detailed, study. We are also confident that, because of the present reports' format, new data and a concept-oriented approach, the result of our study will be of strong interest to various industries, research institutions and numerous governmental agencies.

  4. Neoproterozoic Cana Brava chrysotile deposit (Goiás, Brazil): Geology and geochemistry of chrysotile vein formation

    NASA Astrophysics Data System (ADS)

    Biondi, João Carlos

    2014-01-01

    The Cana Brava chrysotile asbestos deposit of Goiás, Brazil, contains approximately 150 Mt of ore with an average of 3.5 wt.% of cross-fiber chrysotile and lies in the differentiated, mafic-ultramafic Neoproterozoic Cana Brava complex. This complex was formed at approximately 0.79 Ga and metamorphosed at 0.77 to 0.76 and 0.63 Ga. The 0.77 to 0.76 Ga metamorphic event was a high-grade one that transformed the mafic and ultramafic rocks into meta-peridotites and meta-pyroxenites. The low-grade 0.63 Ga metamorphism allowed the formation of black, red and brown serpentinite, graphitic, magnesite-rich talc serpentinite, and rodingite, which became folded and foliated. At the end of the 0.63 Ga metamorphism, black serpentinites were oxidized to form red serpentinites, the main type of serpentinite that outcrops today at the Cana Brava mineralized region. Post-metamorphic fluids reactivated the process of serpentinization, thereby generating massive green serpentinite from the red. Green formed on the most fractured zones, and double red and green reaction rims formed on the sides of the veins located outside the green serpentinite zones. This process did not cause significant variation in the volume of the rocks and resulted in a strongly reducing system thanks to the loss of Fe2O3 and iron and the subsequent crystallization of magnetite within veinlets and altered rocks. Low angle shear, developed under brittle conditions, caused hydraulic fracturing and the generation of oversaturated, oxidizing fluids that crystallized the cross-fiber chrysotile inside open fractures. Very densely fractured zones with fractures filled with cross-fiber chrysotile constitute the ore that is mined at present.

  5. Geologic uses of formation microscanner (FMS) in Antelope Shale Cymric field, San Joaquin Valley, California

    SciTech Connect

    White, R.E.

    1989-04-01

    A comparison between formation microscanner (FMS) log and core from the Cymric field was made to determine the effectiveness of the FMS in characterizing the Antelope Shale. Comparisons of the FMS log and core were based on a detailed core description, petrography, scanning electron microscopy (SEM), and mineralogical analysis. Results indicate that the FMS log in the Antelope Shale is useful for (1) distinguishing between certain rock types, (2) determining bed thickness and bedding-plane orientations, and (3) detecting some fractures and determining some fracture-plane orientations. However, the FMS log shows some ambiguous responses that can be interpreted only by comparison with the core or other wireline logs. Based on resistivity contrasts, three rock-type groups can be distinguished. From least to most resistive, they are (1) mudstone, (2) argillaceous diatomite/Porcelanite, and (3) sandstone, dolostone, clay-poor porcelanite, and chert. A bed thickness of 1 cm or greater can be resolved using the FMS. Bedding-plane orientations can also be determined and provide a means to orient the core. Detection of fractures in the Antelope Shale is generally limited to those fractures within rock type that display intermediate ranges of resistivity and to the large-scale fractures. Fracture-plane orientations of some fractures can be determined; however, because of poor fracture development in the majority of Antelope Shale rock types, fractures are commonly not visible on both FMS-pad images. This makes determination of fracture-plane orientation difficult, if not impossible, for many of these fractures.

  6. Preliminary modeling of the long-term fate of CO2 following injection into deep geological formations

    SciTech Connect

    Strazisar, B.R.; Shu, C.; Hedges, S.W.

    2006-03-01

    The injection of CO2 into deep saline aquifers is a potential option for greenhouse gas mitigation. However, several key issues, such as underground storage time and the fate of the injected CO2, must be studied before this option becomes economically and socially acceptable. In the current study, a one-dimensional reactive mass-transport model was used to predict the long-term chemical behavior of a deep saline aquifer following CO2 injection, far away from the injection site and representative of basin-scale migration and long-term fate. The dissolution of the injected CO2 into brine causes a sharp drop in pH, and consequently, the acidic brine aggressively reacts with aquifer minerals. Our model also predicts the dissolution of aluminosilicate minerals with the formation of secondary minerals and the precipitation and dissolution of carbonate minerals and is consistent with laboratory-scale CO2 core-flooding experiments. However, the extent and development of reaction fronts depend on the reaction rates used. For example, our modeling results indicate that the transport of carbon can be significantly retarded with respect to the flow of the brine itself, and a significant amount of injected CO2 is immobilized because of mineral trapping. The precise locations and patterns of the carbon reactive transport are sensitive to the reaction rates used, illustrating the need for improved knowledge of reaction kinetics, particularly the in-situ rates of dissolution and precipitation of aluminosilicate minerals, in evaluating mineral trapping of CO2 in deep geological formations.

  7. Site characterization of the highest-priority geologic formations for CO2 storage in Wyoming

    SciTech Connect

    Surdam, Ronald C.; Bentley, Ramsey; Campbell-Stone, Erin; Dahl, Shanna; Deiss, Allory; Ganshin, Yuri; Jiao, Zunsheng; Kaszuba, John; Mallick, Subhashis; McLaughlin, Fred; Myers, James; Quillinan, Scott

    2013-12-07

    This study, funded by U.S. Department of Energy National Energy Technology Laboratory award DE-FE0002142 along with the state of Wyoming, uses outcrop and core observations, a diverse electric log suite, a VSP survey, in-bore testing (DST, injection tests, and fluid sampling), a variety of rock/fluid analyses, and a wide range of seismic attributes derived from a 3-D seismic survey to thoroughly characterize the highest-potential storage reservoirs and confining layers at the premier CO2 geological storage site in Wyoming. An accurate site characterization was essential to assessing the following critical aspects of the storage site: (1) more accurately estimate the CO2 reservoir storage capacity (Madison Limestone and Weber Sandstone at the Rock Springs Uplift (RSU)), (2) evaluate the distribution, long-term integrity, and permanence of the confining layers, (3) manage CO2 injection pressures by removing formation fluids (brine production/treatment), and (4) evaluate potential utilization of the stored CO2

  8. Phased Array Approach To Retrieve Gases, Liquids, Or Solids From Subsurface And Subaqueous Geologic Or Man-Made Formations

    DOEpatents

    Rynne, Timothy M. (Long Beach, CA); Spadaro, John F. (Huntington Beach, CA); Iovenitti, Joe L. (Pleasant Hill, CA); Dering, John P. (Lakewood, CA); Hill, Donald G. (Walnut Creek, CA)

    1998-10-27

    A method of enhancing the remediation of contaminated soils and ground water, production of oil and gas, and production of any solid, gas, and/or liquid from subsurface geologic and man-made formations including the steps of estimating the geometric boundaries of the region containing the material to be recovered, drilling a recovery well(s) into subsurface in a strategic location to recover the material of interest, establishing multiple sources of acoustical power in an array about and spaced-apart from the surface or at various depths below the surface in a borehole(s) and/or well(s), directing a volume of acoustical excitation from the sources into the region containing the material to be recovered, the excitation in the form of either controllable sinusoidal, square, pulsed, or various combinations of these three waveforms, and controlling the phasing, frequency, power, duration, and direction of these waveforms from the sources to increase and control the intensity of acoustical excitation in the region of the material to be recovered to enhance. the recovery of said material from the recovery well(s). The invention will augment any technology affecting the removal of materials from the subsurface.

  9. Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 9, Formation and stability of gas hydrates of the Middle America Trench

    SciTech Connect

    Finley, P.; Krason, J.

    1986-12-01

    This report presents a geological description of the Pacific margin of Mexico and Central America, including regional and local structural settings, geomorphology, geological history, stratigraphy, and physical properties. It provides the necessary regional and geological background for more in-depth research of the area. Detailed discussion of bottom simulating acoustic reflectors, sediment acoustic properties, and distribution of hydrates within the sediments are also included in this report. The formation and stabilization of gas hydrates in sediments are considered in terms of phase relations, nucleation, and crystallization constraints, gas solubility, pore fluid chemistry, inorganic diagenesis, and sediment organic content. Together with a depositional analysis of the area, this report is a better understanding of the thermal evolution of the locality. It should lead to an assessment of the potential for both biogenic and thermogenic hydrocarbon generation. 150 refs., 84 figs., 17 tabs.

  10. U.S. Department of Energy's site screening, site selection, and initial characterization for storage of CO2 in deep geological formations

    USGS Publications Warehouse

    Rodosta, T.D.; Litynski, J.T.; Plasynski, S.I.; Hickman, S.; Frailey, S.; Myer, L.

    2011-01-01

    The U.S. Department of Energy (DOE) is the lead Federal agency for the development and deployment of carbon sequestration technologies. As part of its mission to facilitate technology transfer and develop guidelines from lessons learned, DOE is developing a series of best practice manuals (BPMs) for carbon capture and storage (CCS). The "Site Screening, Site Selection, and Initial Characterization for Storage of CO2 in Deep Geological Formations" BPM is a compilation of best practices and includes flowchart diagrams illustrating the general decision making process for Site Screening, Site Selection, and Initial Characterization. The BPM integrates the knowledge gained from various programmatic efforts, with particular emphasis on the Characterization Phase through pilot-scale CO2 injection testing of the Validation Phase of the Regional Carbon Sequestration Partnership (RCSP) Initiative. Key geologic and surface elements that suitable candidate storage sites should possess are identified, along with example Site Screening, Site Selection, and Initial Characterization protocols for large-scale geologic storage projects located across diverse geologic and regional settings. This manual has been written as a working document, establishing a framework and methodology for proper site selection for CO2 geologic storage. This will be useful for future CO2 emitters, transporters, and storage providers. It will also be of use in informing local, regional, state, and national governmental agencies of best practices in proper sequestration site selection. Furthermore, it will educate the inquisitive general public on options and processes for geologic CO2 storage. In addition to providing best practices, the manual presents a geologic storage resource and capacity classification system. The system provides a "standard" to communicate storage and capacity estimates, uncertainty and project development risk, data guidelines and analyses for adequate site characterization, and guidelines for reporting estimates within the classification based on each project's status. ?? 2011 Published by Elsevier Ltd.

  11. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Annual report, July 12, 1990--September 12, 1991

    SciTech Connect

    Menzie, D.E.

    1992-04-01

    Since reservoirs are heterogeneous, nonuniform, and anisotropic, the success or failure of many enhanced oil recovery techniques rests on our prediction of internal variability and the paths of fluid flow in the reservoir. The main objective of this project is to develop a greater understanding of reservoir heterogeneities through dispersion measurement. In this annual report, an approach to ways to estimate the dispersivities of reservoir rocks from well logs is presented. From a series of rock property measurements and dispersion tests the following studies have been made: A measure of rock heterogeneity is developed by using the effluent concentration at one pore volume injection in a matched viscosity miscible displacement. By this approach, a heterogeneity factor is determined from the measured S-shaped dispersion curve. The parameter f in the Coats-Smith capacitance model is redefined as the dispersion fraction f{sub d} (or mechanical mixing fraction). At the f{sub d} pore volume injection, the dynamic miscible displacement efficiency reaches maximum. Reflected on the dispersion curve, this number corresponds to the peak of the first derivative of concentration. With the concept of dispersion fraction, a unique solution to the capacitance model is obtained, and then an equivalent dispersivity is defined. Through experimental data on Berea and Brown sandstone samples, it has been found that the equivalent dispersivity is an exponential function of the heterogeneity factor and can be used as a reservoir characteristic. Through a key parameter of tortuosity, dispersivity is related to rock petrophysical properties. This semi-theoretical relationship forms the basis for determining dispersivities from well logs. The approach is validated through experimental studies on Berea and Brown sandstone samples. It has been found that the equivalent dispersivity is an exponential function of the heterogeneity factor and can be used as a reservoir characteristic.

  12. Evaluation of the geological relationships to gas hydrate formation and stability. Second annual technical progress report, October 1, 1985--September 30, 1986

    SciTech Connect

    Not Available

    1986-12-31

    Although there are many publications pertaining to gas hydrates, their formation and stability in various geological conditions are poorly known. Therefore, for the same reasons and because of the very broad scope of our research, limited amount and extremely dispersed information, the study regions are very large. Moreover, almost without exception the geological environments controlling gas hydrates formation and stability of the studied regions are very complex. The regions studied (completed and partially completed - total 17 locations) during the reporting period, particularly the Gulf of Mexico and the Middle America Trench, are the most important in this entire research project. In the past, both of these regions have been extensively studied, the presence of gas hydrates confirmed and samples recovered. In our investigation it was necessary not only to review all previous data and interpretations, but to do a thorough analysis of the basins, and a critical evaluation of an previously reported and publicly available but not published information.

  13. Geoscience/engineering characterization of the interwell environment in carbonate reservoirs based on outcrop analogs, Permian Basin, West Texas and New Mexico-stratigraphic hierarchy and cycle stacking facies distribution, and interwell-scale heterogeneity: Grayburg Formation, New Mexico. Final report

    SciTech Connect

    Barnaby, R.J.; Ward, W.B.; Jennings, J.W. Jr.

    1997-06-01

    The Grayburg Formation (middle Guadalupian) is a major producing interval in the Permian Basin and has yielded more than 2.5 billion barrels of oil in West Texas. Grayburg reservoirs have produced, on average, less than 30 percent of their original oil in place and are undergoing secondary and tertiary recovery. Efficient design of such enhanced recovery programs dictates improved geological models to better understand and predict reservoir heterogeneity imposed by depositional and diagenetic controls. The Grayburg records mixed carbonate-siliciclastic sedimentation on shallow-water platforms that rimmed the Delaware and Midland Basins. Grayburg outcrops in the Guadalupe and Brokeoff Mountains region on the northwest margin of the Delaware Basin present an opportunity to construct a detailed, three-dimensional image of the stratigraphic and facies architecture. This model can be applied towards improved description and characterization of heterogeneity in analogous Grayburg reservoirs. Four orders of stratigraphic hierarchy are recognized in the Grayburg Formation. The Grayburg represents a long-term composite sequence composed of four high-frequency sequences (HFS 1-4). Each HFS contains several composite cycles comprising two or more cycles that define intermediate-scale transgressive-regressive successions. Cycles are the smallest scale upward-shoaling vertical facies successions that can be recognized and correlated across various facies tracts. Cycles thus form the basis for establishing the detailed chronostratigraphic correlations needed to delineate facies heterogeneity.

  14. Amazonis Planitia: The role of geologically recent volcanism and sedimentation in the formation of the smoothest plains on Mars

    NASA Astrophysics Data System (ADS)

    Fuller, Elizabeth R.; Head, James W.

    2002-10-01

    Amazonis Planitia, located between the two main volcanic provinces on Mars (Tharsis and Elysium), is characterized by extremely smooth topography at several scale lengths, as smooth as oceanic abyssal plains topography on Earth. We use Mars Global Surveyor (MGS) data (primarily very high resolution Mars Orbiter Laser Altimeter (MOLA) topography and derivative slope maps, gradient maps, and detrended maps) to examine the surface morphology of Amazonis Planitia and the stratigraphic relationships among previously mapped and newly defined units. These new data reveal the presence of a 1300 km diameter Noachian impact basin in northwest Amazonis Planitia and an extensive Late Hesperian lava flow unit that appears to have originated from the Olympus Mons source area prior to aureole formation. The presence of this previously unrecognized flow unit strongly suggests that Olympus Mons activity dates back to at least the Hesperian, as did activity on the Tharsis Montes. Emplacement of this ~100 meter thick flow unit formed a barrier along the northern margin of Amazonis Planitia which had a profound influence on the subsequent geologic history of the region. Formation of Olympus Mons aureole deposits created an eastern topographic barrier, and subsequent Tharsis Montes lava flows entered the basin from the south, flowing around the aureole. These three barriers (degraded Noachian crater rim, proto-Olympus Mons flow unit, and Olympus Mons aureole) caused subsequent lava flows and outflow channel effluents, primarily from the Elysium region to the west, to pond on the floor of Amazonis Planitia, preferentially smoothing the terrain there. Mars Orbiter Camera (MOC) images substantiate that at least two very fluid lava flows alternated with fluvial episodes from Elysium Planitia, flowing through Marte Valles onto the floor of the Amazonis Planitia basin. Within Amazonis Planitia, MOC images show flow-like textures heavily mantled by sediments, and radar data reveal the presence of rough lava flow surfaces underlying the sedimentary debris. These data thus suggest that the unique smoothness of Amazonis Planitia is the result of deposition of thin fluid lava flows and fluvial sediments in an enclosed basin. Crater counts suggest that the most recent resurfacing may have occurred in the latest Amazonian Period, in the last 1% of the history of Mars. In light of its unique history, it is somewhat ironic to note that Amazonis Planitia was originally thought to be a typical young Martian surface and therefore used to name the Amazonian era.

  15. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been made. Petrophysical and engineering property characterization is progressing. Data on reservoir production rate and pressure history at Appleton and Vocation Fields have been tabulated, and porosity data from core analysis has been correlated with porosity as observed from well log response. Data integration is on schedule, in that, the geological, geophysical, petrophysical and engineering data collected to date for Appleton and Vocation Fields have been compiled into a fieldwide digital database for reservoir characterization, modeling and simulation for the reef and carbonate shoal reservoirs for each of these fields.

  16. Geologic and hydrologic data for the Rustler Formation near the Waste Isolation Pilot Plant, southeastern New Mexico

    USGS Publications Warehouse

    Richey, Steven F.

    1989-01-01

    The U.S. Geological Survey is investigating the geohydrology in the vicinity of the Waste Isolation Pilot Plant in southeastern New Mexico. Data presented were compiled in support of a regional groundwater flow model. The data include water level measurements obtained from the U.S. Geological Survey 's Groundwater Site-Inventory and OMNIANA data bases and stratigraphic information interpreted from commercial geophysical logs. (USGS)

  17. Probabilistic risk assessment for CO2 storage in geological formations: robust design and support for decision making under uncertainty

    NASA Astrophysics Data System (ADS)

    Oladyshkin, Sergey; Class, Holger; Helmig, Rainer; Nowak, Wolfgang

    2010-05-01

    CO2 storage in geological formations is currently being discussed intensively as a technology for mitigating CO2 emissions. However, any large-scale application requires a thorough analysis of the potential risks. Current numerical simulation models are too expensive for probabilistic risk analysis and for stochastic approaches based on brute-force repeated simulation. Even single deterministic simulations may require parallel high-performance computing. The multiphase flow processes involved are too non-linear for quasi-linear error propagation and other simplified stochastic tools. As an alternative approach, we propose a massive stochastic model reduction based on the probabilistic collocation method. The model response is projected onto a orthogonal basis of higher-order polynomials to approximate dependence on uncertain parameters (porosity, permeability etc.) and design parameters (injection rate, depth etc.). This allows for a non-linear propagation of model uncertainty affecting the predicted risk, ensures fast computation and provides a powerful tool for combining design variables and uncertain variables into one approach based on an integrative response surface. Thus, the design task of finding optimal injection regimes explicitly includes uncertainty, which leads to robust designs of the non-linear system that minimize failure probability and provide valuable support for risk-informed management decisions. We validate our proposed stochastic approach by Monte Carlo simulation using a common 3D benchmark problem (Class et al. Computational Geosciences 13, 2009). A reasonable compromise between computational efforts and precision was reached already with second-order polynomials. In our case study, the proposed approach yields a significant computational speedup by a factor of 100 compared to Monte Carlo simulation. We demonstrate that, due to the non-linearity of the flow and transport processes during CO2 injection, including uncertainty in the analysis leads to a systematic and significant shift of predicted leakage rates towards higher values compared with deterministic simulations, affecting both risk estimates and the design of injection scenarios. This implies that, neglecting uncertainty can be a strong simplification for modeling CO2 injection, and the consequences can be stronger than when neglecting several physical phenomena (e.g. phase transition, convective mixing, capillary forces etc.). The authors would like to thank the German Research Foundation (DFG) for financial support of the project within the Cluster of Excellence in Simulation Technology (EXC 310/1) at the University of Stuttgart. Keywords: polynomial chaos; CO2 storage; multiphase flow; porous media; risk assessment; uncertainty; integrative response surfaces

  18. Formation of nitro-PAHs from the heterogeneous reaction of ambient particle-bound PAHs with NO3/N2O5

    NASA Astrophysics Data System (ADS)

    Zimmermann, K.; Jariyasopit, N.; Simonich, S. L.; Atkinson, R.; Arey, J.

    2012-12-01

    Polycyclic aromatic hydrocarbons (PAHs) and their nitrated derivatives (nitro-PAHs) have been shown to be mutagenic in bacterial and mammalian assays and are classified as probable human carcinogens. Semi-volatile PAHs partition between the gas and particulate phases, depending on their liquid-phase vapor pressures and ambient temperatures. These PAHs have been extensively measured in ambient particulate matter and can ultimately undergo long-range transport from source regions (e.g., China to the western USA) (1). During transport these particle-bound PAHs may undergo reaction with NO3/N2O5 to form nitro-PAH derivatives. Previous studies of heterogeneous nitration of PAHs have used particles composed of graphite, diesel soot, and wood smoke (2-4). This study investigates the heterogeneous formation of nitro-PAHs from ambient particle-bound PAHs from Beijing, China and sites located within the Los Angeles air basin. These ambient particle samples, along with filters coated with isotopically labeled PAHs, were exposed to a mix of NO2/NO3/N2O5 in a 7000 L Teflon chamber, with analysis focused on the heterogeneous formation of molecular weight 247 and 273 nitro-PAHs. The heterogeneous formation of certain nitro-PAHs (including1-nitropyrene and 1- and 2-nitrotriphenylene) was observed for some, but not all, ambient samples. Formation of nitro-PAHs typically formed through gas-phase reactions (2-nitrofluoranthene and 2-nitropyrene) was not observed. The effect of particle age and local photochemical conditions during sampling on the degree of nitration in environmental chamber reactions, as well as ambient implications, will be presented. 1. Primbs, T.; Simonich, S.; Schmedding, D.; Wilson, G.; Jaffe, D.; Takami, A.; Kato, S.; Hatakeyama, S.; Kajii, Y. Environ. Sci. Technol. 2007, 41, 3551-3558. 2. Esteve, W.; Budzinski, H.; Villenave, E. Atmospheric Environment 2004, 38, 6063-6072. 3. Nguyen, M.; Bedjanian, Y.; Guilloteau, A. Journal of Atmospheric Chemistry 2009, 62, 139-150. 4. Kamens, R. M.; Zhi-Hua, F.; Yao, Y.; Chen, D.; Chen, S.; Vartiainen, M. Chemosphere 1994, 28, 1623-1632.

  19. Identification of discharge zones and quantification of contaminant mass discharges into a local stream from a landfill in a heterogeneous geologic setting

    NASA Astrophysics Data System (ADS)

    Milosevic, N.; Thomsen, N. I.; Juhler, R. K.; Albrechtsen, H.-J.; Bjerg, P. L.

    2012-06-01

    SummaryContaminants from Risby Landfill (Denmark) are expected to leach through the underlying geologic strata and eventually reach the local Risby Stream. Identification of the groundwater discharge zone was conducted systematically by an array of methods including studies on site geology and hydrogeology, ground- and surface water flows and landfill leachate tracing from April 2009 to December 2010. Chemical profiling by driven wells and gradients in streambed temperatures was an efficient method to identify the contaminant discharge area. A considerable variation of leachate indicators, redox parameters and xenobiotic organic compounds were revealed in this area because of a complex geological setting with clay till (interbedded sand lenses) and deposits of sand and peat. Concentrations of leachate indicators decreased from the landfill to the stream, implying attenuation processes. Xenobiotic organic compounds were mainly phenoxy acid herbicides, while petroleum hydrocarbons and chlorinated solvents were found at very few boreholes. Findings of putative metabolites of phenoxy acid herbicides suggest degradation under the anaerobic conditions, which dominated inside and beneath the landfill. The groundwater discharge was quantified by two methods: direct collection of discharged groundwater by seepage meters and calculations from measurement of streambed temperature gradients. The landfill impacted the stream seasonally during dry periods when concentrations in the stream reached groundwater concentration levels. A comparison between mass balance for selected stream stretches and upscaled measurements of the contaminant discharge from groundwater into the stream indicated that only a small part of the actual contaminant discharge of the stream could be explained by the inflowing contaminant discharge from groundwater. Surface runoff and seepage from ponds along the stream impacted by landfill interflow may be important pathways as well. The placement of Risby Landfill near a stream and the complex source and geology causing a large spatial variability of leachate compounds are typical for landfill sites so the approaches and findings from Risby Landfill can be applied to other landfill sites. The study highlights that landfills may pose a risk to surface waters and future studies should be directed towards evaluation of both chemical and ecological risk.

  20. Non-Darcian flow in low-permeability media: key issues related to geological disposal of high-level nuclear waste in shale formations

    NASA Astrophysics Data System (ADS)

    Liu, Hui-Hai

    2014-05-01

    In clay or other low-permeability media, water flow becomes non-Darcian and characterized by the non-linear relationship between water flux and hydraulic gradient. This work is devoted to addressing a number of key issues related to geological disposal of high-level nuclear waste in clay/shale formations. It is demonstrated that water flow velocity in the damaged zone (often considered as a potential preferential advection paths in a repository) surrounding the tunnel is extremely small, as a result of non-Darcian flow behavior, such that solute transport is dominated by diffusion, rather than advection. The finding is also consistent with the often-observed existence of persistent abnormal pressures in shale formations. While relative permeability is the key parameter for modeling the unsaturated flow process, without incorporating non-Darcian flow behavior, significant errors can occur in the determination of relative permeability values from traditional measurement methods. An approach for dealing with temperature impact on non-Darcian flow and a formulation to calculate non-Darcian water flux in an anisotropic medium are presented, taking into consideration that a geological repository is subject to temperature evolution in the near field as a result of heat generated by nuclear waste, and that shale formations are generally anisotropic.

  1. Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources

    DOEpatents

    Vail, W.B. III.

    1991-08-27

    Methods and apparatus are provided for measuring the acoustically modulated electronic properties of geological formations and cement layers adjacent to cased boreholes. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. Voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the leakage current conducted into formation in the vicinity of those electrodes. Simultaneously subjecting the casing and formation to an acoustic source acoustically modulates the leakage current measured thereby providing a measure of the acoustically modulated electronic properties of the adjacent formation. Similarly, methods and apparatus are also described which measure the leakage current into formation while simultaneously subjecting the casing to an applied magnetic field which therefore allows measurement of the magnetically modulated electronic properties of the casing and the adjacent formation. 9 figures.

  2. Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources

    DOEpatents

    Vail, III, William B. (Bothell, WA)

    1991-01-01

    Methods and apparatus are provided for measuring the acoustically modulated electronic properties of geological formations and cement layers adjacent to cased boreholes. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. Voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the leakage current conducted into formation in the vicinity of those electrodes. Simultaneously subjecting the casing and formation to an acoustic source acoustically modulates the leakage current measured thereby providing a measure of the acoustically modulated electronic properties of the adjacent formation. Similarly, methods and apparatus are also described which measure the leakage current into formation while simultaneously subjecting the casing to an applied magnetic field which therefore allows measurement of the magnetically modulated electronic properties of the casing and the adjacent formation.

  3. Advances in Planetary Geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (editor)

    1982-01-01

    Advances in Planetary Geology is a new series intended to serve the planetary geology community with a form for quick and thorough communications. There are no set lists of acceptable topics or formats, and submitted manuscripts will not undergo a formal review. All submissions should be in a camera ready form, preferably spaced, and submitted to the editor.

  4. Distribution of mineralized groundwaters in a deep aquifer due to geological heterogeneities and paleogeographic conditions: the Eocene aquifer in the Aquitaine Basin (France)

    NASA Astrophysics Data System (ADS)

    Malcuit, E.; Négrel, Ph.; Atteia, O.; Petelet-Giraud, E.; Franceschi, M.; Dupuy, A.

    2012-04-01

    In the sedimentary Nord Aquitaine Basin (south-west of France), the Eocene aquifer, mostly confined, is one of the main resources for irrigation, thermo-mineral water, and moreover for drinking water in the Bordeaux region. In this aquifer, a large saline area has been identified, where the groundwaters show high values of mineralization and anomalous levels of critical elements, such as sulfates and fluoride, leading to difficulties of resource exploitation for drinking water supply (i.e. the Entre-deux-Mers area). This study focused on the geochemical, multi-isotopic and hydrogeological characterization of these mineralized groundwaters with the aims to improve the understanding of the origin of the salinity in this mineralized area and how these waters circulate in the Eocene aquifer system. Compared to existing data, many new analysis including both major and trace elements, and several isotope systematics show a common origin for the mineralized groundwaters. These data are completed by a detailed geochemical modeling which determines the chemical processes that led to the acquisition of this mineralization, notwithstanding that the spatial distribution of the mineralization is very heterogeneous. The vertical and lateral localization of the mineralization in the aquifer was scrutinized through with an important paleogeographic reconstruction. This was undertaken to locate horizons which can be source and origin of this mineralization. Following a reinterpretation of existing data and acquisition of new ones (logs, mineralogical analysis of cuttings), several levels have been identified in the Eocene aquifer containing either evaporates, or fluorine. Their geographical organization was designed and the spatial distribution is consistent with geochemical analysis. The extreme lateral variability of the mineralization appears to be rooted in the complexity of the overlapping layers of low permeability within the Eocene aquifer system. A hydrodynamic and geochemical modeling can be run at local scale, in accordance with the regional hydrodynamic model. Both have validated hypotheses on groundwaters circulation within the heterogeneous Eocene aquifer system.

  5. Geologic mapping as a method for the construction of a detailed and testable lithostratigraphic model for the Upper Triassic Chinle Formation of Petrified Forest National Park, Arizona

    NASA Astrophysics Data System (ADS)

    Skinner, L. A.; Martz, J. W.; Parker, W.; Raucci, J.; Umhoefer, P. J.

    2010-12-01

    The Upper Triassic Chinle Formation in Petrified Forest National Park represents some of the most intensively studied Upper Triassic strata in western North America. Five stratigraphic members are exposed within the park, from oldest to youngest: the Mesa Redondo, Blue Mesa, Sonsela, Petrified Forest, and Owl Rock Members. Despite numerous stratigraphic studies of the Chinle Formation and two attempts at mapping the park over the past sixty years, sandstone marker beds in the Sonsela Member at the north and south ends of the park were still poorly mapped and correlated. Studies in the years 2002 and 2006 claimed that two sandstones which previous workers had considered to lie at different stratigraphic levels (the Jasper Forest Bed and the Flattops One sandstones in the Martha’s Butte beds) were actually correlative. This correlation resulted in a three-part division of the Sonsela Member and had a major impact on vertebrate biostratigraphy. In a recent attempt to resolve confusions regarding Chinle Formation lithostratigraphy and biostratigraphy, we have completely walked out lithologic contacts through most of the park. The resulting new geologic map, revised lithostratigraphic model, and associated data resolves the 2002 and 2006 miscorrelations by demonstrating that the Jasper Forest Bed capping Blue Mesa and Agate Mesa and Flattops One sandstones (Martha’s Butte beds) are stratigraphically distinct, resulting in a thicker and more complex five-part model for the Sonsela Member, and considerably modifying the vertebrate biostratigraphy. New geologic mapping also resulted in a detailed lithostratigraphic framework for the northern park which has previously been poorly understood, and several important new marker beds, including a purple-gray bed that represents the base of the Owl Rock Member. The revised geologic map is an ArcGIS product that includes an updated lithostratigraphic model for the Chinle Formation, fossil localities, and hyperlinks to labeled photographs of measured sections. A pre-existing ArcGIS product created by workers at Northern Arizona University was used for the creation of this map and thus the final product includes some mapping, mostly Quaternary alluvium, dunes, and sandsheets, from that study. The cumulative effect of these revisions is to emphasize the importance of thoroughly exploring stratigraphic contacts, extensively documenting lithostratigraphic models, making georeferenced GIS maps, and accurately locating critical fossil localities. These methods and the new map make lithostratigraphic, biostratigraphic, and paleoecologic and paleoclimate models scientifically testable to future researchers at this classic Chinle Formation location.

  6. Characterization of Pliocene and Miocene Formations in the Wilmington Graben, Offshore Los Angeles, for Large-Scale Geologic Storage of CO?

    SciTech Connect

    Bruno, Michael

    2014-12-08

    Geomechanics Technologies has completed a detailed characterization study of the Wilmington Graben offshore Southern California area for large-scale CO? storage. This effort has included: an evaluation of existing wells in both State and Federal waters, field acquisition of about 175 km (109 mi) of new seismic data, new well drilling, development of integrated 3D geologic, geomechanics, and fluid flow models for the area. The geologic analysis indicates that more than 796 MMt of storage capacity is available within the Pliocene and Miocene formations in the Graben for midrange geologic estimates (P50). Geomechanical analyses indicate that injection can be conducted without significant risk for surface deformation, induced stresses or fault activation. Numerical analysis of fluid migration indicates that injection into the Pliocene Formation at depths of 1525 m (5000 ft) would lead to undesirable vertical migration of the CO? plume. Recent well drilling however, indicates that deeper sand is present at depths exceeding 2135 m (7000 ft), which could be viable for large volume storage. For vertical containment, injection would need to be limited to about 250,000 metric tons per year per well, would need to be placed at depths greater than 7000ft, and would need to be placed in new wells located at least 1 mile from any existing offset wells. As a practical matter, this would likely limit storage operations in the Wilmington Graben to about 1 million tons per year or less. A quantitative risk analysis for the Wilmington Graben indicate that such large scale CO? storage in the area would represent higher risk than other similar size projects in the US and overseas.

  7. Strontium isotope tracking of groundwater-CO2 interactions in Chimayo, New Mexico, and implications for carbon storage in geologic formations

    NASA Astrophysics Data System (ADS)

    Gardiner, J.; Stewart, B. W.; Capo, R.; Hakala, J.

    2009-12-01

    James Gardiner1, Brian Stewart1, Rosemary Capo1, J. Alexandra Hakala2 1Department of Geology and Planetary Sciences, University of Pittsburgh 2National Energy Technology Laboratory, Pittsburgh, PA The storage of carbon dioxide in geologic formations requires sensitive monitors of the geochemical and mineralogical interactions of storage units, their formation waters, and associated aquifers potentially affected by subsurface CO2. High CO2 subsurface environments can serve as natural analogues for conditions following CO2 injection and provide sites to develop and optimize geochemical tools that can characterize subsurface reactions and identify and track brine and groundwater interactions. Wells in Chimayó, NM tap groundwater from the Tesuque sandstone aquifer, which is crosscut by faults that act as conduits for naturally occurring, deeply sourced CO2. This provides an opportunity for geochemical and isotopic characterization of groundwaters potentially influenced by interaction with CO2. Well waters in the region have 87Sr/86Sr ratios ranging from 0.7176 for CO2-charged brackish water to 0.7098 for a low-TDS groundwater, making the Sr isotope system a potentially sensitive tracer for groundwater-rock interactions. Preliminary strontium isotopic and geochemical data lead to the following observations: (1) Strontium isotope ratios and Sr concentrations in groundwaters sampled within the basin suggest a complex mixing between deep- and shallow-sourced waters, possibly combined with reactions of aquifer carbonate cement or local limestone. (2) Adjacent wells with identical 87Sr/86Sr but significantly different CO2 and alkaline earth concentrations imply CO2 migration from depth into a shallow aquifer, followed by dissolution of carbonate cement. (3) Sr isotope mixing models, when used in conjunction with other geochemical data, can be a strong indicator of decoupling between CO2 and its carrier fluid. Conservative isotope tracers such as 87Sr/86Sr could be an essential tool in monitoring CO2 -groundwater-brine interactions related to geologic carbon sequestration.

  8. Geologic assessment of undiscovered oil and gas resources: Oligocene Frio and Anahuac Formations, United States Gulf of Mexico coastal plain and State waters

    USGS Publications Warehouse

    Swanson, Sharon M.; Karlsen, Alexander W.; Valentine, Brett J.

    2013-01-01

    The Oligocene Frio and Anahuac Formations were assessed as part of the 2007 U.S. Geological Survey (USGS) assessment of Tertiary strata of the U.S. Gulf of Mexico Basin onshore and State waters. The Frio Formation, which consists of sand-rich fluvio-deltaic systems, has been one of the largest hydrocarbon producers from the Paleogene in the Gulf of Mexico. The Anahuac Formation, an extensive transgressive marine shale overlying the Frio Formation, contains deltaic and slope sandstones in Louisiana and Texas and carbonate rocks in the eastern Gulf of Mexico. In downdip areas of the Frio and Anahuac Formations, traps associated with faulted, rollover anticlines are common. Structural traps commonly occur in combination with stratigraphic traps. Faulted salt domes in the Frio and Anahuac Formations are present in the Houston embayment of Texas and in south Louisiana. In the Frio Formation, stratigraphic traps are found in fluvial, deltaic, barrier-bar, shelf, and strandplain systems. The USGS Tertiary Assessment Team defined a single, Upper Jurassic-Cretaceous-Tertiary Composite Total Petroleum System (TPS) for the Gulf Coast basin, based on previous studies and geochemical analysis of oils in the Gulf Coast basin. The primary source rocks for oil and gas within Cenozoic petroleum systems, including Frio Formation reservoirs, in the northern, onshore Gulf Coastal region consist of coal and shale rich in organic matter within the Wilcox Group (Paleocene–Eocene), with some contributions from the Sparta Sand of the Claiborne Group (Eocene). The Jurassic Smackover Formation and Cretaceous Eagle Ford Formation also may have contributed substantial petroleum to Cenozoic reservoirs. Modeling studies of thermal maturity by the USGS Tertiary Assessment Team indicate that downdip portions of the basal Wilcox Group reached sufficient thermal maturity to generate hydrocarbons by early Eocene; this early maturation is the result of rapid sediment accumulation in the early Tertiary, combined with the reaction kinetic parameters used in the models. A number of studies indicate that the migration of oil and gas in the Cenozoic Gulf of Mexico basin is primarily vertical, occurring along abundant growth faults associated with sediment deposition or along faults associated with salt domes. The USGS Tertiary assessment team developed a geologic model based on recurring regional-scale structural and depositional features in Paleogene strata to define assessment units (AUs). Three general areas, as described in the model, are found in each of the Paleogene stratigraphic intervals assessed: “Stable Shelf,” “Expanded Fault,” and “Slope and Basin Floor” zones. On the basis of this model, three AUs for the Frio Formation were defined: (1) the Frio Stable Shelf Oil and Gas AU, containing reservoirs with a mean depth of about 4,800 feet in normally pressured intervals; (2) the Frio Expanded Fault Zone Oil and Gas AU, containing reservoirs with a mean depth of about 9,000 feet in primarily overpressured intervals; and (3) the Frio Slope and Basin Floor Gas AU, which currently has no production but has potential for deep gas resources (>15,000 feet). AUs also were defined for the Hackberry trend, which consists of a slope facies stratigraphically in the middle part of the Frio Formation, and the Anahuac Formation. The Frio Basin Margin AU, an assessment unit extending to the outcrop of the Frio (or basal Miocene), was not quantitatively assessed because of its low potential for production. Two proprietary, commercially available databases containing field and well production information were used in the assessment. Estimates of undiscovered resources for the five AUs were based on a total of 1,734 reservoirs and 586,500 wells producing from the Frio and Anahuac Formations. Estimated total mean values of technically recoverable, undiscovered resources are 172 million barrels of oil (MMBO), 9.4 trillion cubic feet of natural gas (TCFG), and 542 million barrels of natural gas liquids for all of the Frio and Anahuac AUs. Of the five units asse

  9. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Annual report, July 12, 1992--July 12, 1993

    SciTech Connect

    Menzie, D.E.

    1994-01-01

    Dispersion of fluids flowing through porous media is an important phenomenon in miscible displacement. Much of the research involving dispersion and dispersivity as a property of reservoir rock has focused on miscible liquid-liquid displacement processes. This study addresses the measurement of dispersion in a gas-gas displacement system. It will enlarge the understanding of the characteristics of dispersivity and flow systems of reservoir rocks. New experimental methods and apparatus for gas-gas dispersion were developed in this study. Twenty eight gas-gas miscible displacement measurements under different flowrates and pressures were conducted on three Berea sandstone cores of varying lengths and physical properties. A gas chromatograph was utilized and modified to measure the concentration of gas at the outlet of the cores. Nitrogen was used as the displacing gas, while helium was used as the displaced gas. The experimental results were illustrated using S-shaped effluent breakthrough curves. The effect of flowrate and pressure on gas-gas dispersion, dispersion coefficient, dispersivity, and dispersion factor were determined from these curves. Gas effective diffusion coefficients were obtained by graphical methods using the dispersion coefficients under low velocities. A new method to determine the total flowing pore volume by dispersion measurement was proposed in this study. The heterogeneity of reservoir rock can be studied by this method. An increase in displacing velocity was found to decrease the mixing or dispersion of gases in porous media under low pressure (15, 30 and 40 psig). The presumption was made that a critical velocity exists for a given displacement, below which the increase of velocity results in a decrease in dispersion, and above which an increase in dispersion occurs. An increase in pressure will decrease the mixing of gases when the displacement velocity remains constant.

  10. CO2 injection modeling in large scale heterogeneous aquifers

    NASA Astrophysics Data System (ADS)

    Audigane, P. D.; Michel, A.; Trenty, L.; Yamamoto, H.; Gabalda, S.; Anciaux Sedrakian, A.; Chiaberge, C.

    2011-12-01

    Numerical modeling of CO2 injection in heterogeneous media remains a challenging issue with actual computing facilities when considering large size models. In addition, the lack of data available for modeling calibration induces a large degree of uncertainties on the reservoir heterogeneity estimates. We propose here the study of three scenarios using different geological context. The first case is based on the Tenth SPE Comparative Solution Project Model 2. This fine-scale geological model contains 1.1 million cells with a top part representative of a prograding near shore environment while the lower part is fluvial. Simulated CO2 injection has been conducted considering the possibility of water re-injection to maintain the overpressure below the fracture pressure. The second case is based on the French Paris Basin geological context. The area covers a 100 km by 100 km domain (South East of Paris) in which data from about 70 wells and seismic grid have been used to build a 3D grid containing the Dogger carbonate formation as well as the lower part of the Oxfordian clay formation (the caprock) and the upper part of the Aalenian (below the Dogger). Major faults of the geological system have also been incorporated in the structural scheme. Petrophysical properties have been generated using stochastic approach. Porosity variability is simulated for each facies and correlated to permeability. Injection point has been selected in order to avoid fault reactivation. The last case is a representative of the Trias geological formation in France. The 3D regular Cartesian grid contains facies variability built using process based method to represent fluvial deposit architecture. The high geothermal gradient identified in this geological formation allows for the consideration of geothermal production. In this context, we performed CO2 injection simulation to evaluate the mass flow and heat extraction rates from enhanced geothermal injection-production systems using CO2 as heat transmission fluid. Two numerical codes have been used to perform the simulation and handling the high computing demand: (i) TOUGH2-MP, a parallel version of the TOUGH2 code; and (ii) COORES, a black oil reservoir simulator developed at IFPEN. From this study, the limitations of flow simulator to provide pertinent evaluation of overpressure, and plume migration with regard to the considered scale and the role of reservoir heterogeneities on the CO2 storage performance and security is discussed and analyzed.

  11. An integrated multi-scale hydrogeological model for performance and safety assessment of French geological high level and long live radwaste disposal in clay formation

    NASA Astrophysics Data System (ADS)

    Benabderrahmane, H.; Cornaton, F. J.; Kerrou, J.

    2009-12-01

    A deep geological repository of high level and long live radwaste requires sound understanding of the far field and near field groundwater flow and transport properties. Andra, French National radioactive waste management Agency is developing since last 15 years, an integrated multi-scale hydrogeological model of whole Paris basin of 200'000 Km2 area (regional scale) to produce a regional flow field associated to groundwater behavior. It includes locally the Meuse / Haute Marne clay site of about 250 Km2 area in the eastern part of Paris basin that was chosen for the emplacement of a repository. Callovo-Oxfordian as host formation is a clay layer characterized by very low permeability, a mean thickness of 130 m at about 500 m depth and is embedded by calcareous formations as aquifers (Dogger and Oxfordian). The hydrogeological conceptual model is based on stratigraphic and petrophysic modeling of the Paris basin and is accounting for the sound structural, geological, hydrogeological and geochemical data in an integrated way. At Paris basin scale, the model is a multilayer system of 27 layers (hydrogeological units) from Trias to Tertiary. A refinement at local scale of the site defines 27 hydro-geological units from Trias to Portlandian within an area of 1800 Km2. Based on sound data acquisition from borehole and seismic campaigns performed by Andra, regional faults, minor and diffuse fractures are considered. A structural and petrophysical representation of the transition zone between the Paris basin scale and site scale, as well as a better handling of surface flow boundary conditions are considered. Finite element flow and transport simulator Ground Water code (GW) is used to solve for groundwater flow at steady-state in a 1.8 Million nodes model, considering current climatic conditions. The model is calibrated against about 1250 hydraulic head measurements, and results in maximum absolute hydraulic head differences of 20 meters at the regional scale and 5 meters at the local scale. The calibrated reference model includes transmissive major faults as well as structures acting as barrier to flow. Advective-dispersive age solutions are also carried out and compared to available age dates of pore water within the two main calcareous aquifers (Dogger and Oxfordian) that embed Callovo-Oxfordian host formation, to consolidate calibration of flow and to analyze internal water mixing processes and hydraulic behavior of major faults. Lifetime expectancy solutions combined with age solutions are also used to map in the 3-D space the low- and high-speed flow zones at the local scale.

  12. Banded iron-formations of late Proterozoic age in the central eastern desert, Egypt: geology and tectonic setting.

    USGS Publications Warehouse

    Sims, P.K.; James, H.L.

    1984-01-01

    Iron-formation occurs as stratigraphic units within a layered andesite-basalt sequence. The sequence is metamorphosed to greenschist facies, intruded by syntectonic granodiorite and post-tectonic granite, and complexly deformed and grossly fragmented; the rocks are allochthonous along thrust faults. The iron deposits are chemical precipitates, accumulated during lulls in volcanism, apparently in an intraoceanic island-arc environment. The deposits are of the Algoma type of iron-formation.-G.J.N.

  13. Rapid high temperature formation of polychlorinated dioxins and furans in the bed region of a heterogeneous spouted bed combustor: Development of a surface mediated model for the formation of dioxins

    SciTech Connect

    Ghorishi, S.B.; Altwicker, E.R.

    1996-12-31

    The rapid high temperature (580-680{degrees}C) formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the heterogeneous bed region of a spouted bed combustor occurred within fraction of seconds (0.1-0.2 seconds) using two different precursors; 1,2-dichlorobenzene and 2,4-dichlorophenol. Levels of PCDD/Fs produced from 2,4-dichlorophenol oxidation were two orders of magnitude higher than those produced from 1,2-dichlorobenzene, indicating that the high temperature PCDD/Fs formation rate is much faster from chlorophenol precursors. In agreement with typical incinerator observations observations, the PCDDs to PCDFs ratios were less than one under all conditions. Modeling calculations were performed using gas phase mechanisms for the formation of PCDDs with chlorophenols as precursors, under the conditions existing in the high temperature bed region. A semiempirical surface-mediated model is suggested for estimating the formation of PCDDs from chlorophenols. 25 refs., 3 figs., 4 tabs.

  14. Certain aspects of the formation and identification of nanosized oxide components in heterogeneous catalysts prepared by different methods

    NASA Astrophysics Data System (ADS)

    Ellert, Ol'ga G.; Tsodikov, Mark V.; Novotortsev, Vladimir M.

    2010-10-01

    The results of studies into the relationship 'methods and synthesis conditions of a catalyst?catalyst structure?catalytic properties' in highly efficient crystallo-graphically amorphous copper- and iron-containing heterogeneous systems obtained by different chemical methods are generalized. Polymorphism of active phases and catalytic properties of nanostructured copper-containing zinc, zirconium, manganese and cerium oxides are discussed. Unusual transformations of nanosized Pt- and Pd-containing components on the ?-Al2O3 surface in nanostructured catalysts of ethanol steam reforming into synthesis gas and reductive dehydration of ethanol to alkanes are considered. The results of comparative studies on the crystallographically amorphous mixed iron oxide catalysts synthesized by either the alkoxy method or the deposition on various supports obtained by the Mössbauer and XAFS spectroscopy and magnetic susceptibility measurements are presented. These materials are shown to be efficient catalysts of important processes such as liquid-phase oxidation of hydrocarbons, synthesis of alkenes and alkylaromatic hydrocarbons from CO and H2, hydrogenative transformation of brown coal organic mass to hydrocarbons.

  15. Mining geology of the Pond Creek seam, Pikeville Formation, Middle Pennsylvanian, in part of the Eastern Kentucky Coal Field, USA

    USGS Publications Warehouse

    Greb, S.F.; Popp, J.T.

    1999-01-01

    The Pond Creek seam is one of the leading producers of coal in the Eastern Kentucky Coal Field. The geologic factors that affect mining were investigated in several underground mines and categorized in terms of coal thickness, coal quality, and roof control. The limits of mining and thick coal are defined by splitting along the margin of the coal body. Within the coal body, local thickness variation occurs because of (1) leader coal benches filling narrow, elongated depressions, (2) rider coal benches coming near to or merging with the main bench, (3) overthrust coal benches being included along paleochannel margins, (4) cutouts occuring beneath paleochannels, and (5) very hard and unusual rock partings occuring along narrow, elongated trends. In the study area, the coal is mostly mined as a compliance product: sulfur contents are less than 1% and ash yields are less than 10%. Local increases in sulfur occur beneath sandstones, and are inferred to represent post-depositional migration of fluids through porous sands into the coal. Run-of-mine quality is also affected by several mine-roof conditions and trends of densely concentrated rock partings, which lead to increased in- and out-of-seam dilution and overall ash content of the mined coal. Roof control is largely a function of a heterolithic facies mosaic of coastal-estuarine origin, regional fracture trends, and unloading stress related to varying mine depth beneath the surface. Lateral variability of roof facies is the rule in most mines. The largest falls occur beneath modern valleys and parallel fractures, along paleochannel margins, within tidally affected 'stackrock,' and beneath rider coals. Shale spalling, kettlebottoms, and falls within other more isolated facies also occur. Many of the lithofacies, and falls related to bedding weaknesses within or between lithofacies, occur along northeast-southwest trends, which can be projected in advance of mining. Fracture-related falls occur independently of lithofacies trends along northwest-southeast trends, especially beneath modern valleys where overburden thickness decreases sharply. Differentiating roof falls related to these trends can aid in predicting roof quality in advance of mining.The Pond Creek-Lower Elkhorn seam has been an important exploration target because it typically has very low sulfur contents and ash yields. Geologic research in several large Pond Creek mines suggested variability in roof quality and coal thickness. Due to mine access, geologic problems encountered during mining are documented and described.

  16. Characterizing aquifer heterogeneity using hydraulic tomography

    E-print Network

    Wachter, Brian James

    2008-07-29

    Fine-scale heterogeneity in a geologic medium determines rates and directions of flow and of contaminant transport. Traditional methods of determining hydraulic conductivity provide only average values of hydraulic ...

  17. CO{sub 2} Sequestration Capacity and Associated Aspects of the Most Promising Geologic Formations in the Rocky Mountain Region: Local-Scale Analyses

    SciTech Connect

    Laes, Denise; Eisinger, Chris; Morgan, Craig; Rauzi, Steve; Scholle, Dana; Scott, Phyllis; Lee, Si-Yong; Zaluski, Wade; Esser, Richard; Matthews, Vince; McPherson, Brian

    2013-07-30

    The purpose of this report is to provide a summary of individual local-­?scale CCS site characterization studies conducted in Colorado, New Mexico and Utah. These site-­? specific characterization analyses were performed as part of the “Characterization of Most Promising Sequestration Formations in the Rocky Mountain Region” (RMCCS) project. The primary objective of these local-­?scale analyses is to provide a basis for regional-­?scale characterization efforts within each state. Specifically, limits on time and funding will typically inhibit CCS projects from conducting high-­? resolution characterization of a state-­?sized region, but smaller (< 10,000 km{sup 2}) site analyses are usually possible, and such can provide insight regarding limiting factors for the regional-­?scale geology. For the RMCCS project, the outcomes of these local-­?scale studies provide a starting point for future local-­?scale site characterization efforts in the Rocky Mountain region.

  18. Large-eddy simulation of three mixed-phase cloud events during ISDAC: Conditions for persistent heterogeneous ice formation

    NASA Astrophysics Data System (ADS)

    Savre, J.; Ekman, A. M. L.

    2015-08-01

    A Classical-Nucleation-Theory-based parameterization for heterogenous ice nucleation, including explicit dependencies of the nucleation rates on the number concentration, size, and composition of the ambient aerosol population, is implemented in a cloud-scale, large-eddy simulation model and evaluated against Arctic mixed-phase cloud events observed during Indirect and Semi-Direct Aerosol Campaign (ISDAC). An important feature of the parameterization is that the ice nucleation efficiency of each considered aerosol type is described using a contact angle distribution which evolves with time so that the model accounts for the inhibition of ice nucleation as the most efficient ice-forming particles are nucleated and scavenged. The model gives a reasonable representation of first-order (ice water paths) and second-order (ice crystal size distributions) ice microphysical properties. The production of new ice crystals in the upper part of the cloud, essential to guarantee sustained mixed-phase conditions, is found to be controlled mostly by the competition between radiative cooling (resulting in more aerosol particles becoming efficient ice nuclei as the temperature decreases), cloud-top entrainment (entraining fresh particles into the cloud), and nucleation scavenging of the ice+forming aerosol particles. The relative contribution of each process is mostly determined by the cloud-top temperature and the entrainment rates. Accounting for the evolution of the contact angle probability density function with time seems to be essential to capture the persistence of in-cloud ice production without having to, for example, increase the free tropospheric aerosol concentration. Although limited to only three cases and despite important limitations of the parameterization (e.g., the present version only considers dust and black carbon as potential ice nuclei), the results suggest that modeling the time evolution of the ice nuclei population ability to form ice is required to accurately model Arctic mixed-phase cloud processes.

  19. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2004-02-25

    The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on reservoir architecture and geographic distribution of Smackover reservoirs is the fabric and texture of the depositional lithofacies, diagenesis (chiefly dolomitization) is a significant factor that preserves and enhances reservoir quality. The evaporative pumping mechanism is favored to explain the dolomitization of the thrombolite doloboundstone and dolostone reservoir flow units at Appleton and Vocation Fields. Geologic modeling, reservoir simulation, and the testing and applying the resulting integrated geologic-engineering models have shown that little oil remains to be recovered at Appleton Field and a significant amount of oil remains to be recovered at Vocation Field through a strategic infill drilling program. The drive mechanisms for primary production in Appleton and Vocation Fields remain effective; therefore, the initiation of a pressure maintenance program or enhanced recovery project is not required at this time. The integrated geologic-engineering model developed for a low-relief paleohigh (Appleton Field) was tested for three scenarios involving the variables of present-day structural elevation and the presence/absence of potential reef thrombolite lithofacies. In each case, the predictions based upon the model were correct. From this modeling, the characteristics of the ideal prospect in the basement ridge play include a low-relief paleohigh associated with dendroidal/chaotic thrombolite doloboundstone and dolostone that has sufficient present-day structural relief so that these carbonates rest above the oil-water contact. Such a prospect was identified from the modeling, and it is located northwest of well Permit No. 3854B (Appleton Field) and south of well No. Permit No.11030B (Northwest Appleton Field).

  20. Evaluation of the geological relationships to gas hydrate formation and stability. Progress report, June 16--September 30, 1988

    SciTech Connect

    Krason, J.; Finley, P.

    1988-12-31

    The summaries of regional basin analyses document that potentially economic accumulations of gas hydrates can be formed in both active and passive margin settings. The principal requirement for gas hydrate formation in either setting is abundant methane. Passive margin sediments with high sedimentation rates and sufficient sedimentary organic carbon can generate large quantities of biogenic methane for hydrate formation. Similarly, active margin locations near a terrigenous sediment source can also have high methane generation potential due to rapid burial of adequate amounts of sedimentary organic matter. Many active margins with evidence of gas hydrate presence correspond to areas subject to upwelling. Upwelling currents can enhance methane generation by increasing primary productivity and thus sedimentary organic carbon. Structural deformation of the marginal sediments at both active and passive sites can enhance gas hydrate formation by providing pathways for migration of both biogenic and thermogenic gas to the shallow gas hydrate stability zone. Additionally, conventional hydrocarbon traps may initially concentrate sufficient amounts of hydrocarbons for subsequent gas hydrate formation.

  1. The geological significance of the boundary between the Fort Sill and Signal Mountain Formations in the lower Arbuckle Group (Cambrian)

    SciTech Connect

    Hosey, R.; Donovan, R.N. . Geology Dept.)

    1993-02-01

    During the upper Cambrian, a transgression inundated the Southern Oklahoma aulacogen enveloping a landscape that consisted of hills of Cambrian-aged rhyolite up to 350 m in height. Initial deposits on this topography--the Reagan Formation--consist of siliciclastics that were deposited as alluvium and succeeding tidally-influenced marine sandstones and shales. The siliciclastics grains are made up of local rhyolite, quartz and authigenic glauconite. The overlying Honeycreek Formation is defined by the addition of carbonated detritus in the form of tidally-influenced pelmatozoan grainstones. The passage from the Honeycreek to the overlying Fort Sill Formation of the Arbuckle Group is marked by the incoming of beds of lime mudstone and the gradual disappearance of grainstones and siliciclastics. The contact between the Fort Sill and the overlying thinly-bedded dark grey bioclastic limestones of the Signal Mountain Formation is one of the most distinctive horizons in the Arbuckle Group. The contact evidently marks a substantial change in depositional environment. In detail the contact is sharp and shows evidence of minor erosion, although no karsting has been detected. The authors suggest that the contact surface records a regression, perhaps associated with dolomitization and followed by some erosion. A regression is also indicated by the local occurrence of a laminated tidal flat unit with traces of evaporites that outcrops in the far west of the Slick Hills immediately below the formation contact. They suggest that the Signal Mountains as a transgressive unit, incorporating siliciclastics transported into the area during the regression. It has been suggested that the unconformity reflects localized tectonism associated with the evolution of the Southern Oklahoma aulacogen. On the other hand the surface may correlate with a craton--wide Sauxian' hiatus.

  2. The relationship of dynamical heterogeneity to the Adam-Gibbs and random first-order transition theories of glass formation.

    PubMed

    Starr, Francis W; Douglas, Jack F; Sastry, Srikanth

    2013-03-28

    We carefully examine common measures of dynamical heterogeneity for a model polymer melt and test how these scales compare with those hypothesized by the Adam and Gibbs (AG) and random first-order transition (RFOT) theories of relaxation in glass-forming liquids. To this end, we first analyze clusters of highly mobile particles, the string-like collective motion of these mobile particles, and clusters of relative low mobility. We show that the time scale of the high-mobility clusters and strings is associated with a diffusive time scale, while the low-mobility particles' time scale relates to a structural relaxation time. The difference of the characteristic times for the high- and low-mobility particles naturally explains the well-known decoupling of diffusion and structural relaxation time scales. Despite the inherent difference of dynamics between high- and low-mobility particles, we find a high degree of similarity in the geometrical structure of these particle clusters. In particular, we show that the fractal dimensions of these clusters are consistent with those of swollen branched polymers or branched polymers with screened excluded-volume interactions, corresponding to lattice animals and percolation clusters, respectively. In contrast, the fractal dimension of the strings crosses over from that of self-avoiding walks for small strings, to simple random walks for longer, more strongly interacting, strings, corresponding to flexible polymers with screened excluded-volume interactions. We examine the appropriateness of identifying the size scales of either mobile particle clusters or strings with the size of cooperatively rearranging regions (CRR) in the AG and RFOT theories. We find that the string size appears to be the most consistent measure of CRR for both the AG and RFOT models. Identifying strings or clusters with the "mosaic" length of the RFOT model relaxes the conventional assumption that the "entropic droplets" are compact. We also confirm the validity of the entropy formulation of the AG theory, constraining the exponent values of the RFOT theory. This constraint, together with the analysis of size scales, enables us to estimate the characteristic exponents of RFOT. PMID:23556792

  3. Feldspathic Rock Spectral Detections on Mars: Geologic Context, Possible Formation Mechanisms, and the TES/Themis Perspective

    NASA Astrophysics Data System (ADS)

    Rogers, D.; Nekvasil, H.

    2014-12-01

    Spectral detections from VNIR imaging spectrometers OMEGA and CRISM suggest feldspar-bearing rocks with <5% mafic minerals in restricted locations on Mars. The detections have been interpreted as anorthositic, or alternatively, felsic lithologies such as granite. The detections occur in a variety of contexts, including crater central peaks, walls, and floors, intercrater plains of Noachis Terra, and the Nili patera caldera floor. Here we focus on the Noachis Terra feldspathic rock detections, and present constraints from geologic context and complementary thermal infrared measurements. We also examine mechanisms for forming feldspar-rich lavas from crystal fractionation at the base of thick Martian crust. Noachis Terra exposures exhibit high thermal inertias and deep spectral contrast, consistent with competent, non-porous rock. They commonly overlie olivine basaltic bedrock and are ~20-25 m thick. THEMIS spectra from these units are inconsistent with quartz abundances > 5%, ruling out felsic compositions. THEMIS spectra are consistent with both anorthositic and basaltic lithologies; laboratory spectra of these lithologies are indistinguishable at THEMIS resolution. TES spectra do not match library anorthosites, with ~20-30% modeled pyroxene and ~5-10% olivine. Strong contribution from basaltic sediment to the TES spectra is unlikely given the deeper spectral contrast associated with the feldspathic units than underlying olivine basaltic bedrock. Future work will include spectral comparison with other low silica, feldspathic rocks to determine if there is an analog material that is consistent with both the VNIR and TIR observations. The geologic context of the Noachis units suggests volcanic, rather than plutonic origins, although shallow sills or subglacial eruptive units are possible. Previous experimental and modeling work by Nekvasil showed that feldspar-rich (up to 75 wt%), low-silica lavas may be produced from known Martian basalt by shallow crystallization of liquids residual to partial fractionation at the base of a thick Martian crust. The plagioclase fraction increases with both the extent and depth of fractionation. Given that Noachis Terra is associated with thick highlands crust, this mechanism would be a plausible explanation for feldspathic rock detections in this region.

  4. Geologic structure generated by large-impact basin formation observed at the South Pole-Aitken basin on the Moon

    NASA Astrophysics Data System (ADS)

    Ohtake, Makiko; Uemoto, Kisara; Yokota, Yasuhiro; Morota, Tomokatsu; Yamamoto, Satoru; Nakamura, Ryosuke; Haruyama, Junichi; Iwata, Takahiro; Matsunaga, Tsuneo; Ishihara, Yoshiaki

    2014-04-01

    The South Pole-Aitken (SPA) basin is the largest clearly recognized basin on the lunar surface. Determining the composition and structure of the SPA basin interior provides critical constraints on the deep crustal and/or mantle composition of the Moon and improves our understanding of large-basin-forming impact processes. Here we present a new mineralogical map of the SPA basin interior, based on high-spatial-resolution reflectance spectra using the SELENE (Kaguya) multiband imager, which is combined with topographic data in order to interpret the geologic context. The derived mineralogical map suggests extensive distribution of ejected low-Ca pyroxene-dominant mantle material with the presence of purest anorthosite crustal materials surrounding a possible melt pool of 0.26 to 0.33 of the basin diameter near the basin center, which is significantly smaller than that suggested by the crater-scaling law. The absence of clear evidence of lower crustal material is consistent with recent impact simulation results.

  5. Heterogeneous distribution of plankton within the mixed layer and its implications for bloom formation in tropical seas

    NASA Astrophysics Data System (ADS)

    Calbet, Albert; Agersted, Mette Dalgaard; Kaartvedt, Stein; Møhl, Malene; Møller, Eva Friis; Enghoff-Poulsen, Søren; Paulsen, Maria Lund; Solberg, Ingrid; Tang, Kam W.; Tönnesson, Kajsa; Raitsos, Dionysios E.; Nielsen, Torkel Gissel

    2015-06-01

    Intensive sampling at the coastal waters of the central Red Sea during a period of thermal stratification, prior to the main seasonal bloom during winter, showed that vertical patches of prokaryotes and microplankton developed and persisted for several days within the apparently density uniform upper layer. These vertical structures were most likely the result of in situ growth and mortality (e.g., grazing) rather than physical or behavioural aggregation. Simulating a mixing event by adding nutrient-rich deep water abruptly triggered dense phytoplankton blooms in the nutrient-poor environment of the upper layer. These findings suggest that vertical structures within the mixed layer provide critical seeding stocks that can rapidly exploit nutrient influx during mixing, leading to winter bloom formation.

  6. Heterogeneous distribution of plankton within the mixed layer and its implications for bloom formation in tropical seas

    PubMed Central

    Calbet, Albert; Agersted, Mette Dalgaard; Kaartvedt, Stein; Møhl, Malene; Møller, Eva Friis; Enghoff-Poulsen, Søren; Paulsen, Maria Lund; Solberg, Ingrid; Tang, Kam W.; Tönnesson, Kajsa; Raitsos, Dionysios E.; Nielsen, Torkel Gissel

    2015-01-01

    Intensive sampling at the coastal waters of the central Red Sea during a period of thermal stratification, prior to the main seasonal bloom during winter, showed that vertical patches of prokaryotes and microplankton developed and persisted for several days within the apparently density uniform upper layer. These vertical structures were most likely the result of in situ growth and mortality (e.g., grazing) rather than physical or behavioural aggregation. Simulating a mixing event by adding nutrient-rich deep water abruptly triggered dense phytoplankton blooms in the nutrient-poor environment of the upper layer. These findings suggest that vertical structures within the mixed layer provide critical seeding stocks that can rapidly exploit nutrient influx during mixing, leading to winter bloom formation. PMID:26062783

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

    DOEpatents

    Vail, W.B. III.

    1993-02-16

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

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

    DOEpatents

    Vail, III, William B. (Bothell, WA)

    1993-01-01

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

  9. Advances in planetary geology

    SciTech Connect

    Not Available

    1987-06-01

    The surface of Mars displays a broad range of channel and valley features. There is as great a range in morphology as in scale. Some of the features of Martian geography are examined. Geomorphic mapping, crater counts on selected surfaces, and a detailed study of drainage basins are used to trace the geologic evolution of the Margaritifer Sinus Quandrangle. The layered deposits in the Valles Marineris are described in detail and the geologic processes that could have led to their formation are analyzed.

  10. Advances in Planetary Geology

    NASA Technical Reports Server (NTRS)

    Grant, John A., III; Nedell, Susan S.

    1987-01-01

    The surface of Mars displays a broad range of channel and valley features. There is as great a range in morphology as in scale. Some of the features of Martian geography are examined. Geomorphic mapping, crater counts on selected surfaces, and a detailed study of drainage basins are used to trace the geologic evolution of the Margaritifer Sinus Quandrangle. The layered deposits in the Valles Marineris are described in detail and the geologic processes that could have led to their formation are analyzed.

  11. Geologic Map Database of Texas

    USGS Publications Warehouse

    Stoeser, Douglas B.; Shock, Nancy; Green, Gregory N.; Dumonceaux, Gayle M.; Heran, William D.

    2005-01-01

    The purpose of this report is to release a digital geologic map database for the State of Texas. This database was compiled for the U.S. Geological Survey (USGS) Minerals Program, National Surveys and Analysis Project, whose goal is a nationwide assemblage of geologic, geochemical, geophysical, and other data. This release makes the geologic data from the Geologic Map of Texas available in digital format. Original clear film positives provided by the Texas Bureau of Economic Geology were photographically enlarged onto Mylar film. These films were scanned, georeferenced, digitized, and attributed by Geologic Data Systems (GDS), Inc., Denver, Colorado. Project oversight and quality control was the responsibility of the U.S. Geological Survey. ESRI ArcInfo coverages, AMLs, and shapefiles are provided.

  12. Geological setting and paleomagnetism of the Eocene red beds of Laguna Brava Formation (Quebrada Santo Domingo, northwestern Argentina)

    NASA Astrophysics Data System (ADS)

    Vizán, H.; Geuna, S.; Melchor, R.; Bellosi, E. S.; Lagorio, S. L.; Vásquez, C.; Japas, M. S.; Ré, G.; Do Campo, M.

    2013-01-01

    The red bed succession cropping out in the Quebrada Santo Domingo in northwestern Argentina had been for long considered as Upper Triassic-Lower Jurassic in age based on weak radiometric and paleontological evidence. Preliminary paleomagnetic data confirmed the age and opened questions about the nature of fossil footprints with avian features discovered in the section. Recently the stratigraphic scheme was reviewed with the identification of previously unrecognized discontinuities, and a radiometric dating obtained in a tuff, indicated an Eocene age for the Laguna Brava Formation and the fossil bird footprints, much younger than the previously assigned. We present a detailed paleomagnetic study interpreted within a regional tectonic and stratigraphic framework, looking for an explanation for the misinterpretation of the preliminary paleomagnetic data. The characteristic remanent magnetizations pass a tilt test and a reversal test. The main magnetic carrier is interpreted to be low Ti titanomagnetites and to a lesser extent hematite. The characteristic remanent magnetization would be essentially detrital. The obtained paleomagnetic pole (PP) for the Laguna Brava Formation has the following geographic coordinates and statistical parameters: N = 29, Lon. = 184.5° E, Lat. = 75.0° S, A95 = 5.6° and K = 23.7. When this PP is compared with another one with similar age obtained in an undeformed area, a declination anomaly is recognized. This anomaly can be interpreted as Laguna Brava Formation belonging to a structural block that rotated about 16° clockwise along a vertical axis after about 34 Ma. This block rotation is consistent with the regional tectonic framework, and would have caused the fortuitous coincidence of the PP with Early Jurassic poles. According to the interpreted magnetostratigraphic correlation, the Laguna Brava Formation would have been deposited during the Late Eocene with a mean sedimentation rate of about 1.4 cm per thousand years, probably in relation to the onset of the Andean deformation.

  13. Issues of engineering and geochemistry in the sequestration of carbon dioxide in geological formations-saline aquifers

    NASA Astrophysics Data System (ADS)

    Garcia Orrego, Gloria Stella

    Dynamic tests were conducted to evaluate the feasibility to sequester carbon dioxide (CO2) in carbonate dolomite reservoir. Two injection rates, 0.1613 cc/min (20 pore volumes) and 0.982 cc/min (120 pore volumes) were tested to observe changes in petrophysical parameters mainly permeability and porosity under these two conditions of flow rates. The low flow rate was allowed to evaluate the effect of the bulk of the reservoir and the high flow rate evaluated the effect of dissolution on the face of the formation. The testes were carried out at reservoir-simulated conditions (2000 psia and 150°F). San Andres dolomite formation cores from wells 744 and 745 drilled during pilot area evaluation in Levelland Field. The core samples used have a high content of anhydrite and they are cemented mainly by calcite. The formation water used is representative of the Permian basin brine which has sodium 18,000 mg/L, chlorine 46,200 mg/L, calcium 6000 mg/L, sulfate 4880 mg/L, magnesium 1820 mg/L and potassium 1510 mg/L. The injection of low pore volumes was found to reduce the permeability in about 50%, the pore volume and porosity in about 25%, and the total equilibrium magnetization (Mo) from NMR T2 distribution decreased in about 17% indicating substantial reduction in porosity and permeability. The small pore sizes (bulk volume irreducible-BVI) increased in average in about 70% and the large pore sized (free fluid index-FFI) decreased in about 24%. The injection of high pore volume showed slight increase of the petrophysical properties. The total equilibrium magnetization and BVI and FFI did not present remarkable change. At the onset of this research, it was still uncertain how the interaction between CO2 and formation brine affects the geochemistry of the reservoir. Therefore, several static tests at supercritical conditions (1070 psia and 88°F) and at reservoir conditions with and without rock samples were carried out. After running the static tests for seven days, a precipitate from the brine was obtained after reaction with CO2. The precipitate was analyzed using transmission electron microscopy (TEM) to identify the specimen structure and to obtain a chemical analysis using energy-dispersive spectrometers (EDS). Also, the X-ray diffraction method (XRD) was used to identify the new minerals formed as a consequence of the interaction between CO2 and formation brine. The main observations indicate that the precipitated is mainly formed by calcite, gypsum, halite and other mineral salts. (Abstract shortened by UMI.)

  14. GeoTemp™ 1.0: A MATLAB-based program for the processing, interpretation and modelling of geological formation temperature measurements

    NASA Astrophysics Data System (ADS)

    Ricard, Ludovic P.; Chanu, Jean-Baptiste

    2013-08-01

    The evaluation of potential and resources during geothermal exploration requires accurate and consistent temperature characterization and modelling of the sub-surface. Existing interpretation and modelling approaches of 1D temperature measurements are mainly focusing on vertical heat conduction with only few approaches that deals with advective heat transport. Thermal regimes are strongly correlated to rock and fluid properties. Currently, no consensus exists for the identification of the thermal regime and the analysis of such dataset. We developed a new framework allowing the identification of thermal regimes by rock formations, the analysis and modelling of wireline logging and discrete temperature measurements by taking into account the geological, geophysical and petrophysics data. This framework has been implemented in the GeoTemp software package that allows the complete thermal characterization and modelling at the formation scale and that provides a set of standard tools for the processing wireline and discrete temperature data. GeoTempTM operates via a user friendly graphical interface written in Matlab that allows semi-automatic calculation, display and export of the results. Output results can be exported as Microsoft Excel spreadsheets or vector graphics of publication quality. GeoTemp™ is illustrated here with an example geothermal application from Western Australia and can be used for academic, teaching and professional purposes.

  15. Geology and geochemistry of the Macheng Algoma-type banded iron-formation, North China Craton: Constraints on mineralization events and genesis of high-grade iron ores

    NASA Astrophysics Data System (ADS)

    Wu, Huaying; Niu, Xianglong; Zhang, Lianchang; Pirajno, Franco; Luo, Huabao; Qin, Feng; Cui, Minli; Wang, Changle; Qi, Min

    2015-12-01

    The Macheng iron deposit is located in the eastern Hebei province of the North China Craton (NCC). It is hosted in Neoarchean metamorphic rocks of Baimiaozi formation in the Dantazi Group, consisting of biotite-leptynite, plagioclase-gneiss, plagioclase-amphibolite, migmatite, migmatitic granite and quartz schist. Geochemical analyses of the host biotite leptynite and plagioclase amphibolites show that their protoliths are both volcanics, inferred to be trachytic basalt and basaltic andesite, respectively. Based on the geochemical signature of the host rocks, together with geology of the iron deposit, it is inferred that the Macheng BIF is an Algoma-type iron exhalative formation, formed in an arc-related basin in the Neoarchean. Post-Archean Australian Shale (PAAS)-normalized rare earth elements (REEs) plus yttrium (Y) concentrations of different BIF ores with gneissic, striated and banded structure in the Macheng deposit, show similar patterns with depletions in light rare earth elements (LREEs) and middle rare earth elements (MREEs) relative to heavy rare earth elements (HREEs) and with apparently positive La, Y and Eu anomalies. Y/Ho ratios of the gneissic, striated and banded BIF ores vary from 37 to 56. These geochemical features of the BIF ores reveal their affinity with the sea water and the presence of a high-temperature hydrothermal component, indicating that both the seawater and high temperature hydrothermal fluids derived from alteration of oceanic basalts and komatiites may contribute to formation of the Macheng BIF. Geological, mineralogical and geochemical studies of the Macheng deposit recognized two kinds of high-grade iron ores. One is massive oxidized high-grade ore (Fe2O3T = 74.37-86.20 wt.%), mainly consisting of hematite with some magnetite, which shows geochemical characteristics of the gneissic, striated and banded BIF ores. The other type is magnetite high-grade ore, also massive and consisting of magnetite, with distinct characteristics in trace elements of the gneissic, striated and banded BIF ores but show similarity to those of the migmatitic iron ores with significantly negative Eu anomalies. The geochemical discrepancy or duality between the two types of high-grade ores in Macheng suggests that they formed by two different mechanisms. One is related to supergene enrichment, caused by oxidation of magnetite and the leaching of gangue minerals from BIF to form high-grade ore. The other is probably related to intensive migmatization which produced high-grade ores by altering the primary iron ores.

  16. Heterogeneous atmospheric chemistry

    NASA Technical Reports Server (NTRS)

    Schryer, D. R.

    1982-01-01

    The present conference on heterogeneous atmospheric chemistry considers such topics concerning clusters, particles and microparticles as common problems in nucleation and growth, chemical kinetics, and catalysis, chemical reactions with aerosols, electron beam studies of natural and anthropogenic microparticles, and structural studies employing molecular beam techniques, as well as such gas-solid interaction topics as photoassisted reactions, catalyzed photolysis, and heterogeneous catalysis. Also discussed are sulfur dioxide absorption, oxidation, and oxidation inhibition in falling drops, sulfur dioxide/water equilibria, the evidence for heterogeneous catalysis in the atmosphere, the importance of heterogeneous processes to tropospheric chemistry, soot-catalyzed atmospheric reactions, and the concentrations and mechanisms of formation of sulfate in the atmospheric boundary layer.

  17. Geologic Reconnaissance of the Antelope-Ashwood Area, North-Central Oregon: With Emphasis on the John Day Formation of Late Oligocene and Early Miocene Age

    USGS Publications Warehouse

    Peck, Dallas L.

    1964-01-01

    This report briefly describes the geology of an area of about 750 square miles in Jefferson, Wasco, Crook, and Wheeler Counties, Oregon. About 16,000 feet of strata that range in age from pre-Tertiary to Quaternary are exposed. These include the following units: pre-Tertiary slate, graywacke, conglomerate, and meta-andesite; Clarno Formation of Eocene age - lava flows, volcanic breccia, tuff, and tuffaceous mudstone, chiefly of andesitic composition; John Day Formation of late Oligocene and early Miocene age - pyroclastic rocks, flows, and domes, chiefly of rhyolitic composition; Columbia River Basalt of middle Miocene age - thick, columnar jointed flows of very fine grained dense dark-gray basalt; Dalles Formation of Pliocene age - bedded tuffaceous sandstone, siltstone, and conglomerate; basalt of Pliocene or Pleistocene age - lava flows of porous-textured olivine basalt; and Quaternary loess, landslide debris, and alluvium. Unconformities separate pre-Tertiary rocks and Clarno Formation, Clarno and John Day Formations, John Day Formation and Columbia River Basalt, and Columbia River Basalt and Dalles Formation. The John Day Formation, the only unit studied in detail, consists of about 4,000 feet of tuff, lapilli tuff, strongly to weakly welded rhyolite ash flows, and less abundant trachyandesite flows and rhyolite flows and domes. The formation was divided into nine mappable members in part of the area, primarily on the basis of distinctive ledge-forming welded ash-flow sheets. Most of the sheets are composed of stony rhyolite containing abundant lithophysae and sparse phenocrysts. One sheet contains 10 to 20 percent phenocrysts, mostly cryptoperthitic soda sanidine, but including less abundant quartz, myrmekitic intergrowths of quartz and sanidine, and oligoclase. The rhyolitic ash flows and lava flows were extruded from nearby vents, in contrast to some of the interbedded air-fall tuff and lapilli tuff of dacitic and andesitic composition that may have been derived from vents in an ancestral Cascade Range. The John Day is dated on the basis of a late Oligocene flora near the base of the formation and early Miocene faunas near the top of the formation. The middle Miocene and older rocks in the Antelope-Ashwood area are broadly folded and broken along northeast-trending faults. Over much of the area the rocks dip gently eastward from the crest of a major fold and are broken along a series of steeply dipping antithetic strike faults. Pliocene and Quaternary strata appear to be undeformed. At the Priday agate deposit, chalcedony-filled spherulites (thunder-eggs) occur in the lower part of a weakly welded rhyolitic ash flow. The so-called thunder-eggs are small spheroidal bodies, about 3 inches in average diameter; each consists of a chalcedonic core surrounded by a shell of welded tuff that is altered to radially oriented fibers of cristobalite and alkalic feldspar.

  18. Separation and capture of CO2 from large stationary sources and sequestration in geological formations--coalbeds and deep saline aquifers.

    PubMed

    White, Curt M; Strazisar, Brian R; Granite, Evan J; Hoffman, James S; Pennline, Henry W

    2003-06-01

    The topic of global warming as a result of increased atmospheric CO2 concentration is arguably the most important environmental issue that the world faces today. It is a global problem that will need to be solved on a global level. The link between anthropogenic emissions of CO2 with increased atmospheric CO2 levels and, in turn, with increased global temperatures has been well established and accepted by the world. International organizations such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC) have been formed to address this issue. Three options are being explored to stabilize atmospheric levels of greenhouse gases (GHGs) and global temperatures without severely and negatively impacting standard of living: (1) increasing energy efficiency, (2) switching to less carbon-intensive sources of energy, and (3) carbon sequestration. To be successful, all three options must be used in concert. The third option is the subject of this review. Specifically, this review will cover the capture and geologic sequestration of CO2 generated from large point sources, namely fossil-fuel-fired power gasification plants. Sequestration of CO2 in geological formations is necessary to meet the President's Global Climate Change Initiative target of an 18% reduction in GHG intensity by 2012. Further, the best strategy to stabilize the atmospheric concentration of CO2 results from a multifaceted approach where sequestration of CO2 into geological formations is combined with increased efficiency in electric power generation and utilization, increased conservation, increased use of lower carbon-intensity fuels, and increased use of nuclear energy and renewables. This review covers the separation and capture of CO2 from both flue gas and fuel gas using wet scrubbing technologies, dry regenerable sorbents, membranes, cryogenics, pressure and temperature swing adsorption, and other advanced concepts. Existing commercial CO2 capture facilities at electric power-generating stations based on the use of monoethanolamine are described, as is the Rectisol process used by Dakota Gasification to separate and capture CO2 from a coal gasifier. Two technologies for storage of the captured CO2 are reviewed--sequestration in deep unmineable coalbeds with concomitant recovery of CH4 and sequestration in deep saline aquifers. Key issues for both of these techniques include estimating the potential storage capacity, the storage integrity, and the physical and chemical processes that are initiated by injecting CO2 underground. Recent studies using computer modeling as well as laboratory and field experimentation are presented here. In addition, several projects have been initiated in which CO2 is injected into a deep coal seam or saline aquifer. The current status of several such projects is discussed. Included is a commercial-scale project in which a million tons of CO2 are injected annually into an aquifer under the North Sea in Norway. The review makes the case that this can all be accomplished safely with off-the-shelf technologies. However, substantial research and development must be performed to reduce the cost, decrease the risks, and increase the safety of sequestration technologies. This review also includes discussion of possible problems related to deep injection of CO2. There are safety concerns that need to be addressed because of the possibilities of leakage to the surface and induced seismic activity. These issues are presented along with a case study of a similar incident in the past. It is clear that monitoring and verification of storage will be a crucial part of all geological sequestration practices so that such problems may be avoided. Available techniques include direct measurement of CO2 and CH4 surface soil fluxes, the use of chemical tracers, and underground 4-D seismic monitoring. Ten new hypotheses were formulated to describe what happens when CO2 is pumped into a coal seam. These hypotheses provide significant insight into the fundamental chemical, physical, a

  19. Environmental Geology

    ERIC Educational Resources Information Center

    Dunn, James R.

    1977-01-01

    Discusses ways that geologic techniques can be used to help evaluate our environment, make economic realities and environmental requirements more compatible, and expand the use of geology in environmental analyses. (MLH)

  20. Remote sensing of fugitive methane emissions from oil and gas production in North American tight geologic formations

    NASA Astrophysics Data System (ADS)

    Schneising, Oliver; Burrows, John P.; Dickerson, Russell R.; Buchwitz, Michael; Reuter, Maximilian; Bovensmann, Heinrich

    2014-10-01

    In the past decade, there has been a massive growth in the horizontal drilling and hydraulic fracturing of shale gas and tight oil reservoirs to exploit formerly inaccessible or unprofitable energy resources in rock formations with low permeability. In North America, these unconventional domestic sources of natural gas and oil provide an opportunity to achieve energy self-sufficiency and to reduce greenhouse gas emissions when displacing coal as a source of energy in power plants. However, fugitive methane emissions in the production process may counter the benefit over coal with respect to climate change and therefore need to be well quantified. Here we demonstrate that positive methane anomalies associated with the oil and gas industries can be detected from space and that corresponding regional emissions can be constrained using satellite observations. On the basis of a mass-balance approach, we estimate that methane emissions for two of the fastest growing production regions in the United States, the Bakken and Eagle Ford formations, have increased by 990 ± 650 ktCH4 yr-1 and 530 ± 330 ktCH4 yr-1 between the periods 2006-2008 and 2009-2011. Relative to the respective increases in oil and gas production, these emission estimates correspond to leakages of 10.1% ± 7.3% and 9.1% ± 6.2% in terms of energy content, calling immediate climate benefit into question and indicating that current inventories likely underestimate the fugitive emissions from Bakken and Eagle Ford.

  1. Geology of the Deer Butte Formation, Malheur county, Oregon: faulting, sedimentation and volcanism in a post-caldera setting

    NASA Astrophysics Data System (ADS)

    Cummings, Michael L.

    1991-11-01

    The Deer Butte Formation accumulated during the middle Miocene in fault-controlled basins in an extensional setting. The basins developed as regional faults asserted influence after eruption of ash-flow sheets and collapse of calderas of the Lake Owyhee volcanic field. The sequences of Hurley Flat, Dry Creek, and Oxbow Basin contain a lower basalt tephradominated unit formed by basalt hydrovolcanism overlain by fine-grained fluvial and lacustrine volcaniclastic sedimentary units. The sequence of Freezeout Creek was deposited in an erosional valley that was incised into older units and cut across the concurrently active Wall Rock Ridge fault zone. The sequence of Hurley Flat and Dry Creek contain alkaline tholeiitic basalt flows and tephra deposits, whereas the sequences of Freezeout Creek and Oxbow Basin contain subalkaline calcalkaline basaltic andesite. The compositional change occurred after local uplift due to faulting along the Wall Rock Ridge fault zone. The youngest unit, well-sorted, medium-grained, muscovite-bearing arkose of the arkose of Dry Creek Buttes, was deposited in a large river that drained westward from source areas in western Idaho. The Deer Butte Formation was deposited between approximately 15 and 12.6 Ma, while basin and range-type faulting dominated regional structural patterns.

  2. Geological setting of oil shales in the Permian phosphoria formation and some of the geochemistry of these rocks

    USGS Publications Warehouse

    Maughan, E.K.

    1983-01-01

    Recent studies of the Meade Peak and the Retort Phosphatic Shale Members of the Phosphoria Formation have investigated the organic carbon content and some aspects of hydrocarbon generation from these rocks. Phosphorite has been mined from the Retort and Meade Peak members in southeastern Idaho, northern Utah, western Wyoming and southwestern Montana. Organic carbon-rich mudstone beds associated with the phosphorite in these two members also were natural sources of petroleum. These mudstone beds were differentially buried throughout the region so that heating of these rocks has been different from place to place. Most of the Phosphoria source beds have been deeply buried and naturally heated to catagenetically form hydrocarbons. Deepest burial was in eastern Idaho and throughout most of the northeastern Great Basin where high ambient temperatures have driven the catagenesis to its limit and beyond to degrade or to destroy the hydrocarbons. In southwest Montana, however, burial in some areas has been less than 2 km, ambient temperatures remained low and the kerogen has not produced hydrocarbons (2). In these areas in Montana, the kerogen in the carbonaceous mudstone has retained the potential for hydrocarbon generation and the carbon-rich Retort Member is an oil shale from which hydrocarbons can be synthetically extracted. The Phosphoria Formation was deposited in a foreland basin between the Cordilleran geosyncline and the North American craton. This foreland basin, which coincides with the area of deposition of the two organic carbon-rich mudstone members of the Phosphoria, has been named the Sublett basin (Maughan, 1979). The basin has a northwest-southeast trending axis and seems to have been deepest in central Idaho where deep-water sedimentary rocks equivalent to the Phosphoria Formation are exceptionally thick. The depth of the basin was increasingly shallower away from central Idaho toward the Milk River uplift - a land area in Montana, the ancestral Rocky Mountains. The basin is composed of land areas in Colorado, the Humboldt highland in northeastern Nevada and intervening carbonate shelves in Utah and Wyoming. The phosphorites and the carbonaceous mudstones were deposited on the foreslope between the carbonate and littoral sand deposits on the shelf and the dominantly cherty mudstone sediments in the axial part of the basin. Paleomagnetic evidence indicates that in the Permian the region would have been within the northern hemispheric trade wind belt; and wind-direction studies determined from studies of sand dunes, indicate that the prevailing winds from the Milk River uplift would have blown offshore across the Phosphoria sea. Offshore winds would have carried surface water away from the shore and generated upwelling in the sea in eastern Idaho and adjacent areas in Montana, Wyoming and Utah. Prior to deposition of the Phosphoria, the region was the site of extensive deposition of shallow-water carbonate sediments. Equivalent rocks in the northern part of the basin are dominantly sandstone derived from the adjacent Milk River uplift and similar sandstone strata in the southeastern sector were derived from the ancestral Rocky Mountains uplift. Tectonic subsidence of the Sublett basin in part of the region seems to have provided a sea-floor profile favorable for upwelling circulation and the shift in deposition from regional carbonates and local sandstone into a more complex depositional pattern that included the accumulation of the mudstone-chert-phosphorite facies that comprises the Phosphoria Formation. High biological productivity and the accumulation of sapropel on the sea floor is associated with contemporary coastal upwelling (1) and similar environmental and depositional conditions are attributed to the rich accumulations of organic matter in the Phosphoria Formation. Sapropelic mudstone and phosphorite composing the Meade Peak Member are approximately 60 m thick near the center of the Sublett basin. The Meade

  3. The Geology of the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Carr, M. H. (editor); Saunders, R. S.; Strom, R. G.; Wilhelms, D. E.

    1984-01-01

    The geologic history of the terrestrial planets is outlined in light of recent exploration and the revolution in geologic thinking. Among the topics considered are planet formation; planetary craters, basins, and general surface characteristics; tectonics; planetary atmospheres; and volcanism.

  4. Environmental Geology

    ERIC Educational Resources Information Center

    Passero, Richard N.

    1978-01-01

    1977 was a year of continued and expanding efforts in the application of the geosciences to land-use planning, especially as they relate to geologic hazards, and elucidating the role of geology in public policy. The work of environmental geological programs is reviewed. (Author/MA)

  5. Novel Nitro-PAH Formation from Heterogeneous Reactions of PAHs with NO2, NO3/N2O5, and OH Radicals: Prediction, Laboratory Studies and Mutagenicity

    PubMed Central

    JARIYASOPIT, NARUMOL; INTOSH, MELISSA MC; ZIMMERMANN, KATHRYN; AREY, JANET; ATKINSON, ROGER; CHEONG, PAUL HA-YEON; CARTER, RICH G.; YU, TIAN-WEI; DASHWOOD, RODERICK H.; SIMONICH, STACI L. MASSEY

    2014-01-01

    The heterogeneous reactions of benzo[a]pyrene-d12 (BaP-d12), benzo[k]fluoranthene-d12 (BkF-d12), benzo[ghi]perylene-d12 (BghiP-d12), dibenzo[a,i]pyrene-d14 (DaiP-d14), and dibenzo[a,l]pyrene (DalP) with NO2, NO3/N2O5, and OH radicals were investigated at room temperature and atmospheric pressure in an indoor Teflon chamber and novel mono NO2-DaiP, and mono NO2-DalP products were identified. Quartz fiber filters (QFF) were used as a reaction surface and the filter extracts were analyzed by GC/MS for nitrated-PAHs (NPAHs) and tested in the Salmonella mutagenicity assay, using Salmonella typhimurium strain TA98 (with and without metabolic activation). In parallel to the laboratory experiments, a theoretical study was conducted to rationalize the formation of NPAH isomers based on the thermodynamic stability of OH-PAH intermediates, formed from OH-radical-initiated reactions. NO2 and NO3/N2O5 were effective oxidizing agents in transforming PAHs to NPAHs, with BaP-d12 being the most readily nitrated. Reaction of BaP-d12, BkF-d12 and BghiP-d12 with NO2 and NO3/N2O5 resulted in the formation of more than one mono-nitro isomer product, while the reaction of DaiP-d14 and DalP resulted in the formation of only one mono-nitro isomer product. The direct-acting mutagenicity increased the most after NO3/N2O5 exposure, particularly for BkF-d12 in which di-NO2-BkF-d10 isomers were measured. The deuterium isotope effect study suggested that substitution of deuterium for hydrogen lowered both the direct and indirect acting mutagenicity of NPAHs and may result in an underestimation of the mutagencity of the novel NPAHs identified in this study. PMID:24350894

  6. Sudbury project (University of Muenster-Ontario Geological Survey): Origin of the polymict, allochthonous breccias of the Onaping Formation

    NASA Technical Reports Server (NTRS)

    Avermann, M. E.

    1992-01-01

    The Sudbury structure has been interpreted as a deeply eroded remnant of a peak-ring basin. The polymict, allochthonous breccias of the Onaping Formation (OF) occur in the central part of the Sudbury structure, which is surrounded by the 1.85-Ga-old 'Sudbury Igneous Complex' (SIC). From bottom to top the OF can be divided into Basal, Gray, Green, and lower and upper Black members. The breccias were mapped in detail in the east range of the structure. The SIC and the lower part of the OF (Basal Member) are interpreted as the impact melt system. The overlying Gray Member is a breccia unit with a clastic matrix and has a sharp contact to the Basal Member. The Green Member is considered as a continuous uniform breccia layer on top of the Gray Member and comprises the former 'chlorite shard horizon'. The uppermost unit of the OF (Black Member) can be subdivided into a lower and an upper Black Member unit. The lower part (100-150 m thick) still shows petrographic features of suevitic breccias, small fragments of basement rocks, melt particles, chloritized particles, and breccia fragments in a dark, clastic matrix.

  7. Dolomitization and neomorphism of Mississippian (Visean) upper debolt formation, Blueberry field, northeastern British Columbia: Geologic, petrologic, and chemical evidence

    SciTech Connect

    Durocher, S.; Al-Aasm, I.S.

    1997-06-01

    Petrographic, chemical, and isotopic studies of the Mississippian (Visean) upper Debolt Formation in the Blueberry field, British Columbia, Canada, reveal that dolomitization was the result of several diagenetic events and that neomorphic alteration of these dolomites significantly modified their original chemical signatures. These studies also demonstrate how tectonics play an important role in controlling and modifying reservoir dolomites in the area. Petrographic investigations have documented two early dolomite phases, (1) early matrix dolomite and (2) pervasive dolomite, and two later generations, (3) coarse cement and (4) pseudomorphic replacement of crinoids. Early matrix dolomite occurs as small (average 25 {mu}m) subhedral to euhedral crystals that replace the matrix of carbonate mudstones, wackestones, and packstones. Petrographic evidence suggests that early matrix dolomite had a relatively early, precompaction origin, possibly from marine fluids. However, geochemical evidence indicates that later fluids have altered their original geochemical signatures. Pervasive dolomite, which forms the reservoir intercrystalline porosity, occurs with planar-s and planar-e textures. Planar-s crystals typically have a dirty appearance and exhibit homogeneous dull brown/red cathodoluminescence colors. Planar-e crystals may appear with a cloudy core and a clear rim, and under cathodoluminescence display an irregular dull brown/red core and a thin, bright red rim. Due to the spatial distribution pattern of pervasive dolomite with respect to the overlying unconformity surface, its paleogeographic distribution and close temporal relationship with meteoric diagenetic events, pervasive dolomite formed from a mixture of seawater and meteoric fluids. However, alteration of their primary chemistry by later fluids is indicated by their depleted {delta}{sup 18}O values and radiogenic {sup 87}Sr/{sup 86}Sr ratios.

  8. Briefing on geological sequestration

    EPA Science Inventory

    Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media – primarily saline formations, depleted or nearly depleted oil and gas...

  9. SEISMIC DETERMINATION OF RESERVOIR HETEROGENEITY: APPLICATION TO THE CHARACTERIZATION OF HEAVY OIL RESERVOIRS

    SciTech Connect

    Matthias G. Imhof; James W. Castle

    2005-02-01

    The objective of the project was to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study focused on West Coalinga Field in California. The project initially attempted to build reservoir models based on different geologic and geophysical data independently using different tools, then to compare the results, and ultimately to integrate them all. We learned, however, that this strategy was impractical. The different data and tools need to be integrated from the beginning because they are all interrelated. This report describes a new approach to geostatistical modeling and presents an integration of geology and geophysics to explain the formation of the complex Coalinga reservoir.

  10. Impacts of Anthropogenic Emissions in the Southeastern U.S. on Heterogeneous Chemistry of Isoprene-Derived Epoxides Leading to Secondary Organic Aerosol Formation (Invited)

    NASA Astrophysics Data System (ADS)

    Surratt, J. D.; Pye, H.; Lin, Y.; Budisulistiorini, S.; Zhang, H.; Marth, W.; Cui, T.; Arashiro, M.; Chu, K.; Zhang, Z.; Sexton, K.; Piletic, I.; Xie, Y.; Capps, S. L.; Luecken, D.; Hutzell, W. T.; Jaoui, M.; Canagaratna, M. R.; Croteau, D.; Jayne, J. T.; Worsnop, D. R.; Offenberg, J.; Kleindienst, T. E.; Lewandowski, M.; Edney, E.; Pinder, R. W.; Bartolotti, L.; Gold, A.

    2013-12-01

    Isoprene is a major source of secondary organic aerosol (SOA); however, the exact manner in which it forms SOA remains unclear. Improving our fundamental understanding of isoprene-derived SOA is key to improving existing air quality models, especially in the southeastern U.S. where models currently underestimate observations. By combining organic synthesis, computational calculations, mass spectrometry, smog chamber studies, and field measurements, we show that reactive epoxides, which include methacrylic acid epoxide (MAE) and isomeric isoprene epoxydiols (IEPOX), produced from the photochemical oxidation of isoprene are key to SOA formation. Furthermore, anthropogenic pollutants (NOx and SO2) enhance isoprene-derived epoxides as an SOA source. In the laboratory, we find that the reactive uptake of synthetic IEPOX and MAE standards onto acidified sulfate aerosol yields known isoprene-derived SOA tracers (2-methlytetrols, 2-methylglyceric acid, C5-alkene triols, 3-methyltetrahydrofuran-3,4-diols, dimers and organosulfates) that we measure in fine aerosol collected from multiple sites across the southeastern U.S. using gas chromatography/mass spectrometry (GC/MS) and liquid chromatography coupled to diode array detection and electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (LC/DAD-ESI-QTOFMS). Notably, IEPOX- and MAE-derived SOA tracers account for ~19% of the organic aerosol mass in Yorkville, GA. Moreover, real-time continuous chemical measurements of fine aerosol made using an Aerodyne Aerosol Chemical Speciation Monitor (ACSM) during summer 2011 and summer 2013 in Atlanta, GA, and Look Rock, TN, respectively, resolved an IEPOX-oxygenated organic aerosol (IEPOX-OOA) factor when applying positive matrix factorization (PMF) to the organic mass spectral time series. In Atlanta, this factor is found to account for ~33% of the fine OA mass and is correlated with IEPOX-derived SOA tracers (r2 = 0.6), sulfate (r2 = 0.5), and to some extent with aerosol acidity (measured as nmol H+ m-3, r2 = 0.3). Altogether, the Community Multiscale Air Quality model is updated to predict isoprene aerosol from IEPOX and MAE. The new aqueous aerosol pathways allow for explicit predictions of IEPOX- and MAE-derived SOA tracers that are more consistent with observations than estimates based on semivolatile partitioning, supporting the role of acid-catalyzed heterogeneous reactions leading to SOA formation.

  11. A primer in lunar geology

    NASA Technical Reports Server (NTRS)

    Greeley, R. (editor); Schultz, P. H. (editor)

    1974-01-01

    Primary topics in lunar geology range from the evolution of the solar system to lunar photointerpretation, impact crater formation, and sampling to analyses on various Apollo lunar landing site geomorphologies.

  12. Geologic controls influencing CO2 loss from a leaking well.

    SciTech Connect

    Hopkins, Polly L.; Martinez, Mario J.; McKenna, Sean Andrew; Klise, Katherine A.

    2010-12-01

    Injection of CO2 into formations containing brine is proposed as a long-term sequestration solution. A significant obstacle to sequestration performance is the presence of existing wells providing a transport pathway out of the sequestration formation. To understand how heterogeneity impacts the leakage rate, we employ two dimensional models of the CO2 injection process into a sandstone aquifer with shale inclusions to examine the parameters controlling release through an existing well. This scenario is modeled as a constant-rate injection of super-critical CO2 into the existing formation where buoyancy effects, relative permeabilities, and capillary pressures are employed. Three geologic controls are considered: stratigraphic dip angle, shale inclusion size and shale fraction. In this study, we examine the impact of heterogeneity on the amount and timing of CO2 released through a leaky well. Sensitivity analysis is performed to classify how various geologic controls influence CO2 loss. A 'Design of Experiments' approach is used to identify the most important parameters and combinations of parameters to control CO2 migration while making efficient use of a limited number of computations. Results are used to construct a low-dimensional description of the transport scenario. The goal of this exploration is to develop a small set of parametric descriptors that can be generalized to similar scenarios. Results of this work will allow for estimation of the amount of CO2 that will be lost for a given scenario prior to commencing injection. Additionally, two-dimensional and three-dimensional simulations are compared to quantify the influence that surrounding geologic media has on the CO2 leakage rate.

  13. Geologic Controls Influencing CO2 Loss from a Leaking Well

    NASA Astrophysics Data System (ADS)

    Klise, K. A.; Martinez, M. J.; McKenna, S. A.; Hopkins, P. L.

    2010-12-01

    Injection of CO2 into formations containing brine is proposed as a long-term sequestration solution. A significant obstacle to sequestration performance is the presence of existing wells providing a transport pathway out of the sequestration formation. To understand how heterogeneity impacts the leakage rate, we employ two dimensional models of the CO2 injection process into a sandstone aquifer with shale inclusions to examine the parameters controlling release through an existing well. This scenario is modeled as a constant-rate injection of super-critical CO2 into the existing formation where buoyancy effects, relative permeabilities, and capillary pressures are employed. Three geologic controls are considered: stratigraphic dip angle, shale inclusion size and shale fraction. In this study, we examine the impact of heterogeneity on the amount and timing of CO2 released through a leaky well. Sensitivity analysis is performed to classify how various geologic controls influence CO2 loss. A “Design of Experiments” approach is used to identify the most important parameters and combinations of parameters to control CO2 migration while making efficient use of a limited number of computations. Results are used to construct a low-dimensional description of the transport scenario. The goal of this exploration is to develop a small set of parametric descriptors that can be generalized to similar scenarios. Results of this work will allow for estimation of the amount of CO2 that will be lost for a given scenario prior to commencing injection. Additionally, two-dimensional and three-dimensional simulations are compared to quantify the influence that surrounding geologic media has on the CO2 leakage rate. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

  14. Geologic Time.

    ERIC Educational Resources Information Center

    Newman, William L.

    One of a series of general interest publications on science topics, the booklet provides those interested in geologic time with an introduction to the subject. Separate sections discuss the relative time scale, major divisions in geologic time, index fossils used as guides for telling the age of rocks, the atomic scale, and the age of the earth.…

  15. Archeological Geology.

    ERIC Educational Resources Information Center

    Gifford, John A.

    1983-01-01

    Discusses some of the publication outlets, from international to relatively esoteric, used in archeological geology and comments on a possible future trend in publication of archeological-geology research. Publication outlets considered include books (including those published by university presses), journals, and government publications.…

  16. Engineering Geology

    ERIC Educational Resources Information Center

    Hatheway, Allen W.

    1978-01-01

    Engineering geology remains a potpourri of applied classical geology, and 1977 witnessed an upswing in demand for these services. Traditional foundation-related work was slight, but construction related to national needs increased briskly. Major cities turned to concerns of transit waste-water treatment and solid-waste disposal. (Author/MA)

  17. Physical geology

    SciTech Connect

    Skinner, B.; Porter, S.

    1987-01-01

    The book integrates current thinking on processes (plate techtonics, chemical cycles, changes throughout geologic time). It is an introduction to investigations into the way the earth works, how mountains are formed, how the atmosphere, hydrosphere, crust and mantle interact with each other. Treatments on climate, paleoclimatology and landscape evolution are included, as is a discussion on how human activity affects geological interactions.

  18. Geological Carbon Storage: The Roles of Government

    E-print Network

    Geological Carbon Storage: The Roles of Government and Industry in Risk Management ROSE MURPHY version of this publication, please send an email to Mark Jaccard (jaccard@sfu.ca). #12;8 Geological to a location suitable for long-term storage. CO2 can be stored in onshore or offshore geological formations

  19. Input-form data for the U.S. Geological Survey assessment of the Devonian and Mississippian Bakken and Devonian Three Forks Formations of the U.S. Williston Basin Province, 2013

    USGS Publications Warehouse

    U.S. Geological Survey Bakken-Three Forks Assessment Team; Gaswirth, Stephanie B.; Marra, Kristen R.; Cook, Troy A.; Charpentier, Ronald R.; Gautier, Donald L.; Higley, Debra K.; Klett, Timothy R.; Lewan, Michael D.; Lillis, Paul G.; Schenk, Christopher J.; Tennyson, Marilyn E.; Whidden, Katherine J.

    2013-01-01

    In 2013, the U.S. Geological Survey assessed the technically recoverable oil and gas resources of the Bakken and Three Forks Formations of the U.S. portion of the Williston Basin. The Bakken and Three Forks Formations were assessed as continuous and hypothetical conventional oil accumulations using a methodology similar to that used in the assessment of other continuous- and conventional-type assessment units throughout the United States. The purpose of this report is to provide supplemental documentation and information used in the Bakken-Three Forks assessment.

  20. Geologic time

    USGS Publications Warehouse

    Newman, William L.

    2000-01-01

    The Earth is very old 4 1/2 billion years or more according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science.

  1. Structural and stratigraphic evolution of the central Mississippi Canyon Area: interaction of salt tectonics and slope processes in the formation of engineering and geologic hazards 

    E-print Network

    Brand, John Richard

    2006-04-12

    Approximately 720 square miles of digital 3-dimensional seismic data covering the eastern Mississippi Canyon area, Gulf of Mexico, continental shelf was used to examine the structural and stratigraphic evolution of the geology in the study area...

  2. Application of geologic-mathematical 3D modeling for complex structure deposits by the example of Lower- Cretaceous period depositions in Western Ust - Balykh oil field (Khanty-Mansiysk Autonomous District)

    NASA Astrophysics Data System (ADS)

    Perevertailo, T.; Nedolivko, N.; Prisyazhnyuk, O.; Dolgaya, T.

    2015-11-01

    The complex structure of the Lower-Cretaceous formation by the example of the reservoir BC101 in Western Ust - Balykh Oil Field (Khanty-Mansiysk Autonomous District) has been studied. Reservoir range relationships have been identified. 3D geologic- mathematical modeling technique considering the heterogeneity and variability of a natural reservoir structure has been suggested. To improve the deposit geological structure integrity methods of mathematical statistics were applied, which, in its turn, made it possible to obtain equal probability models with similar input data and to consider the formation conditions of reservoir rocks and cap rocks.

  3. Chapter 7. The GIS project for the geologic assessment of undiscovered oil and gas in the Cotton Valley group and Travis Peak and Hosston formations, East Texas basin and Louisiana-Mississippi salt basins provinces.

    USGS Publications Warehouse

    Biewick, Laura R.H.

    2006-01-01

    A geographic information system (GIS) focusing on the Upper Jurassic-Lower Cretaceous Cotton Valley Group and the Lower Cretaceous Travis Peak and Hosston Formations in the northern Gulf Coast region was developed as a visual-analysis tool for the U.S. Geological Survey's 2002 assessment of undiscovered, technically recoverable oil and natural gas resources in the East Texas Basin and Louisiana-Mississippi Salt Basins Provinces. The Central Energy Resources Team of the U.S. Geological Survey has also developed an Internet Map Service to deliver the GIS data to the public. This mapping tool utilizes information from a database about the oil and natural gas endowment of the United States-including physical locations of geologic and geographic data-and converts the data into visual layers. Portrayal and analysis of geologic features on an interactive map provide an excellent tool for understanding domestic oil and gas resources for strategic planning, formulating economic and energy policies, evaluating lands under the purview of the Federal Government, and developing sound environmental policies. Assessment results can be viewed and analyzed or downloaded from the internet web site, http://energy.cr.usgs.gov/oilgas/noga/ .

  4. Engineering Geology

    ERIC Educational Resources Information Center

    Lee, Fitzhugh T.

    1974-01-01

    Briefly reviews the increasing application of geologic principles, techniques and data to engineering practices in the areas of land use and zoning controls, resource management energy programs and other fields. (BR)

  5. Environmental Geology

    ERIC Educational Resources Information Center

    Everett, A. Gordon

    1972-01-01

    Briefly summarizes the major applications, during 1971, of geology to environmental problems in the United States and mentions some of the related literature from professional meetings and from other publications. (PR)

  6. Geology, summary

    NASA Technical Reports Server (NTRS)

    Sabins, F. F., Jr.

    1975-01-01

    Trends in geologic application of remote sensing are identified. These trends are as follows: (1) increased applications of orbital imagery in fields such as engineering and environmental geology - some specific applications include recognition of active earthquake faults, site location for nuclear powerplants, and recognition of landslide hazards; (2) utilization of remote sensing by industry, especially oil and gas companies, and (3) application of digital image processing to mineral exploration.

  7. Regional geologic setting and analysis of ostracod fauna from the Lower and Middle Pennsylvanian Round Valley and Morgan formations in Dinosaur National Monument, Utah and Colorado

    NASA Astrophysics Data System (ADS)

    Schlipp, Wayne Richard

    The Pennsylvanian Round Valley, Morgan, and lower Weber formations in Dinosaur National Monument, Utah and Colorado, record a regressive transition from open marine deposition upwards into eolian deposition. Exposures of this sequence provided an opportunity to investigate ostracods as paleoenvironmental indicators. To accomplish this, seven localities in Dinosaur National Monument were measured, described, and sampled for ostracods and associated fauna. Fusulinids provided a time line for correlation of these stratigraphic sections. Six seismic lines and five well logs helped establish that the measured sections lie across depositional strike in the Colorado trough. From samples obtained at one-meter intervals throughout the seven localities, sixteen ostracod genera were identified, counted, and classified. Swimmers, burrowers and crawlers in fine or coarse sediments were classified based on carapace characteristics and related to depositional energy levels from accepted carbonate classifications. Rarefaction curves, heterogeneity, evenness measures, Q-Mode and R-Mode cluster analyses were generated. Rarefaction established that generic richness is greater in low energy carbonates than high energy carbonates, or siliciclastics. Q-Mode and R-Mode analyses indicated a strong association among crawlers in fine sediments, crawlers and burrowers in coarse sediments, and burrowers in fine and coarse sediments. Although statistical analysis of diversity measures revealed no significant difference between energy levels, independent T-tests established that ostracod generic abundances did differ significantly between energy levels. Hence, a conceptual model for Pennsylvanian ostracod habitats was created. Acratia, Knightina, Geisina, Monoceratina, Triceratina, Genus A, and Triceratina preferentially inhabit low depositional energy levels in fine-grained sediments. Bythocypris, Fabalicypris, Pseudoparaparchites, and elongated Bairdia generally inhabit high and low energy environments. Amphissites, Glyptopleura, Kirkbya, Knoxina, small Cavellina, small and spined Paraparchites, and small Bairdia preferentially inhabit high depositional energy levels. Large Bairdia, large Cavellina, and large Paraparchites are swimmers and were recovered from all energy levels. These results establish Pennsylvanian ostracods as paleoenvironmental indicators because they preferred energy levels and substrates similar to those occupied in by ostracods from Recent environments. Also, the biostratigraphic utility of ostracods for dating Pennsylvanian rocks in this region were established in that Triceratina was restricted to Morrowan, and Geisina, Genus A, and Monoceratina were restricted to Des Moinesian.

  8. Borehole geological assessment

    NASA Technical Reports Server (NTRS)

    Spuck, W. H., III (inventor)

    1979-01-01

    A method and apparatus are discussed for performing geological assessments of a formation located along a borehole, and a boring tool that bores a pair of holes into the walls of the borehole and into the surrounding strata along with a pair of probes which are installed in the holes. One of the probes applies an input such as a current or pressured fluid, and the other probe senses a corresponding input which it receives from the strata.

  9. Proterozoic Geology

    NASA Astrophysics Data System (ADS)

    Sims, P. K.

    1984-04-01

    This book and its companion, Early Proterozoic Geology of the Great Lakes Region (Mem. 160 Geological Society of America, 1984), edited by L.G. Medaris, Jr., are the products of an International Proterozoic symposium held at the University of Wisconsin, Madison, May 18-21, 1981. This volume contains 23 papers that present the current thinking of experts on many aspects of Proterozoic evolution of the earth; it is divided into five broad categories: tectonics, magmatism and metamorphism, mineral resources, evolution of life and the atmosphere, and glaciation.The Proterozoic is a distinctive interval in the geologic history of the earth, encompssing the transition from Archean conditions to those of the Phanerozoic. By Early Proterozoic time, extensive stable continental plates existed, and deformation, deposition, and intrusion styles were comparable to those of today. Also, the amount of free oxygen in the atmosphere and hydrosphere continuously increased during the Proterozoic and eventually reached levels supportive of metazoan evolution.

  10. Geological flows

    E-print Network

    Yu. N. Bratkov

    2008-11-19

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  11. Digitizing rocks standardizing the geological description process using workstations

    SciTech Connect

    Saunders, M.R. , Windsor, Berkshire ); Shields, J.A. ); Taylor, M.R. )

    1993-09-01

    The preservation of geological knowledge in a standardized digital form presents a challenge. Data sources, inherently fuzzy, range in scale from the macroscopic (e.g., outcrop) through the mesoscopic (e.g., hand-specimen) core and sidewall core, to the microscopic (e.g., drill cuttings, thin sections, and microfossils). Each scale change results in increased heterogeneity and potentially contradictory data and the providers of such data may vary in experience level. To address these issues with respect to cores and drill cuttings, a geological description workstation has been developed and is undergoing field trials. Over 1000 carefully defined geological attributes are currently available within a depth-indexed, relational database. Attributes are stored in digital form, allowing multiple users to select familiar usage (e.g., diabase vs. dolerite). Data can be entered in one language and retrieved in other languages. The database structure allow groupings of similar elements (e.g., rhyolites in acidic, igneous or volcanics subgroups or the igneous rock group) permitting different uses to analyze details appropriate to the scale of the usage. Data entry uses a graphical user interface, allowing the geologist to make quick, logical selections in a standardized or custom-built format with extensive menus, on-screen graphics and help screens available. Description ranges are permissible. Entries for lithology, petrology, structures (sedimentary, organic and deformational), reservoir characteristics (porosity and hydrocarbon shows), and macrofossils are available. Sampling points for thin sections, core analysis, geochemistry, or micropaleontology studies are also recorded. Using digital data storage, geological logs using graphical, alphanumeric and symbolic depictions are possible. Data can be integrated with drilling and mud gas data, MWD and wireline data and off well-site analyses to produced composite formation evaluation logs and interpretational crossplots.

  12. Testing the Injectivity of CO2 in a Sub-surface Heterogeneous Reservoir

    NASA Astrophysics Data System (ADS)

    Sundal, A.; Nystuen, J.; Dypvik, H.; Aagaard, P.

    2011-12-01

    This case study on subsurface reservoir characterization, considers the effect of geological heterogeneities on the storage capacity and injectivity of the Johansen Formation, which is a deep, saline aquifer underlying the Troll Gas Field off the Norwegian coast. The Johansen Formation has been interpreted as a sandy, prograding unit, deposited in a shallow marine environment during Early Jurassic time, and is overlain by a shaly unit; the Amundsen Formation. It appears as a wedge shaped sandstone body, up to 140m thick, with an areal extent in the order of 10 000 km2. The Johansen Formation is currently being considered for large scale CO2 storage from two gas power plants situated on the west coast of Norway, both of which will operate with full scale CO2 handling, as proposed by Norwegian authorities. The storage capacity needed is in the order of 3 Mt CO2/year. With access to a new 3D seismic survey (Gassnova, 2010), and based on existing well log data from 25 penetrating wells, we have studied large scale geometries and intra-formational features, and built a geo-conceptual model of the Johansen Formation. The reservoir is heterogeneous, with distinct permeability zonation within clinothems separated by less permeable layers. In order to obtain better understanding of crucial reservoir parameters and supplement limited data, comparison of data from easily accessible analogue rock units is useful. For this purpose the unit should be well exposed and thoroughly documented, such as the Panther Tongue Member (Star Point Formation, Mesa Verde Group) in Book Cliffs, from which we have collected some comparable permeability estimates for the model. On a micro scale, mineralogy, grain size/shape and pore geometry constitue major controls on reservoir porosity and permeability. Direct geological information is at this point in time limited to a few meters of core, from which detailed mineralogical information has been derived (optical microscopy, SEM, XRD), and some additional data from side wall cores and cuttings. From this we evaluate facies dependence related to observed diagenetic features and compositional variations due to burial depth (2-4km), mainly considering chlorite coatings (preserving porosity) and cementation (calcite and quartz). Using Schlumberger soft-wares; Petrel (reservoir) and Eclipse (fluid flow), we are testing injection scenarios (one point, several points, bleeding wells) in several intra-formational geological settings. These results will be evaluated relative to the distribution of facies and heterogeneities in the reservoir, considering multiphase flow given the local pressure regime.

  13. Si-rich layer formation on olivine surfaces during reaction with water and supercritical carbon dioxide under conditions relevant for geologic carbon storage

    NASA Astrophysics Data System (ADS)

    Johnson, N. C.; Jackson, A.; Maher, K.; Bird, D. K.; Brown, G. E.

    2013-12-01

    The reaction of Mg-silicate minerals (i.e. olivine) with carbon dioxide (CO2) is a promising method for secure, long-term, geologic carbon storage. Several technical challenges must be overcome before implementing mineral carbonation technology on a large scale, one of which is slow reaction kinetics. This study probes surface reaction limitations of olivine carbonation, specifically the formation of a passivating, Si-rich layer on olivine surfaces upon exposure to water and CO2 under sequestration conditions (elevated temperature and pressure). A series of batch reactions were performed at 60°C and 100 bar CO2 pressure in Dickson-style rocker bombs, varying the length of reaction and the amount of mixing (rocking). The initial aqueous phase was spiked with 29Si. Fluid samples were taken periodically and analyzed for cation content, alkalinity, and dissolved inorganic carbon. At the end of each experiment, the solid products were analyzed with a Sensitive High Resolution Ion Microprobe Reverse Geometry (SHRIMP-RG) in order to measure the amount of 29Si incorporated into the Si-rich layer on reacted olivine grains. We also cut cross sections of reacted grains from each experiment using a Focused Ion Beam (FIB) which were thinned to <100nm and imaged using Transmission Electron Microscopy (TEM). SHRIMP-RG results show incorporation of 29Si on olivine grain surfaces reacted for 19 days with no mixing, and TEM images of olivine grains from the same experiment show an amorphous, Si-rich layer that is 30nm thick. Similarly, SHRIMP-RG results for olivine grains reacted for 19 days with mixing indicate 29SiO2 precipitation and TEM images reveal a Si-rich layer 60nm thick. In both experiments, EDS (energy dispersive spectroscopy) data show a step change in composition from the bulk rock to the surface layer in addition to the sharp crystalline/amorphous interface visible in the TEM images. Olivine from the unmixed experiment also has a slow decrease in Mg relative to Si before the step change, suggesting that, at least in this experiment, a Si-rich layer precipitated on top of a Mg-depleted layer that formed via a leaching process. SHRIMP-RG data also imply the presence of a precipitated Si-rich layer on top of a leached Si-rich layer, as the 29Si penetration depth is only 25-65% of the total Si-rich layer thickness. The combination of SHRIMP-RG and FIB/TEM analysis leads us to hypothesize that a Si-rich layer forms quickly on olivine surfaces due to preferential Mg removal from the surface (the traditional 'leached' layer), and as the reaction proceeds, amorphous silica reaches saturation in the fluid and precipitates on surfaces inside the reactor (including olivine grains).

  14. Geologic Time.

    ERIC Educational Resources Information Center

    Albritton, Claude C., Jr.

    1984-01-01

    Discusses the historical development of the concept of geologic time. Develops the topic by using the major discoveries of geologists, beginning with Steno and following through to the discovery and use of radiometric dating. An extensive reference list is provided. (JM)

  15. Geological processes and evolution

    USGS Publications Warehouse

    Head, J.W.; Greeley, R.; Golombek, M.P.; Hartmann, W.K.; Hauber, E.; Jaumann, R.; Masson, P.; Neukum, G.; Nyquist, L.E.; Carr, M.H.

    2001-01-01

    Geological mapping and establishment of stratigraphic relationships provides an overview of geological processes operating on Mars and how they have varied in time and space. Impact craters and basins shaped the crust in earliest history and as their importance declined, evidence of extensive regional volcanism emerged during the Late Noachian. Regional volcanism characterized the Early Hesperian and subsequent to that time, volcanism was largely centered at Tharsis and Elysium, continuing until the recent geological past. The Tharsis region appears to have been largely constructed by the Late Noachian, and represents a series of tectonic and volcanic centers. Globally distributed structural features representing contraction characterize the middle Hesperian. Water-related processes involve the formation of valley networks in the Late Noachian and into the Hesperian, an ice sheet at the south pole in the middle Hesperian, and outflow channels and possible standing bodies of water in the northern lowlands in the Late Hesperian and into the Amazonian. A significant part of the present water budget occurs in the present geologically young polar layered terrains. In order to establish more firmly rates of processes, we stress the need to improve the calibration of the absolute timescale, which today is based on crater count systems with substantial uncertainties, along with a sampling of rocks of unknown provenance. Sample return from carefully chosen stratigraphic units could calibrate the existing timescale and vastly improve our knowledge of Martian evolution.

  16. Modeling Supercritical Carbon Dioxide Injection in Heterogeneous Porous Media

    SciTech Connect

    Doughty, Christine; Pruess, Karsten

    2003-04-10

    We investigate the physical processes that occur during the sequestration of carbon dioxide (CO2) in liquid-saturated, brine-bearing geologic formations using the numerical simulator TOUGH2. CO2 is injected in a supercritical state that has a much lower density and viscosity than the liquid brine it displaces. In situ, the supercritical CO2 forms a gas-like phase, and also partially dissolves in the aqueous phase, creating a multi-phase, multi-component environment that shares many important features with the vadose zone. The flow and transport simulations employ an equation of state package that treats a two-phase (liquid, gas), three-component (water, salt, CO2) system. Chemical reactions between CO2 and rock minerals that could potentially contribute to mineral trapping of CO2 are not included. The geological setting considered is a fluvial/deltaic formation that is strongly heterogeneous, making preferential flow a significant effect, especially when coupled with the strong buoyancy forces acting on the gas-like CO2 plume. Key model development issues include vertical and lateral grid resolution, grid orientation effects, and the choice of characteristic curves.

  17. Mathematical Geology, Vol. 4, No. 3, 1972 Mathematical Techniques for Paleocurrent Analysis

    E-print Network

    Jammalamadaka, S. Rao

    Mathematical Geology, Vol. 4, No. 3, 1972 Mathematical Techniques for Paleocurrent Analysis procedure. Finally, theprocedures for testing the homogeneity of directional data from several geological directions from different geological formations belong to significantly different populations. KEY WORDS

  18. Method of analysis at the U.S. Geological Survey California Water Science Center, Sacramento Laboratory - determination of haloacetic acid formation potential, method validation, and quality-control practices

    USGS Publications Warehouse

    Zazzi, Barbara C.; Crepeau, Kathryn L.; Fram, Miranda S.; Bergamaschi, Brian A.

    2005-01-01

    An analytical method for the determination of haloacetic acid formation potential of water samples has been developed by the U.S. Geological Survey California Water Science Center Sacramento Laboratory. The haloacetic acid formation potential is measured by dosing water samples with chlorine under specified conditions of pH, temperature, incubation time, darkness, and residual-free chlorine. The haloacetic acids formed are bromochloroacetic acid, bromodichloroacetic acid, dibromochloroacetic acid, dibromoacetic acid, dichloroacetic acid, monobromoacetic acid, monochloroacetic acid, tribromoacetic acid, and trichloroacetic acid. They are extracted, methylated, and then analyzed using a gas chromatograph equipped with an electron capture detector. Method validation experiments were performed to determine the method accuracy, precision, and detection limit for each of the compounds. Method detection limits for these nine haloacetic acids ranged from 0.11 to 0.45 microgram per liter. Quality-control practices include the use of blanks, quality-control samples, calibration verification standards, surrogate recovery, internal standard, matrix spikes, and duplicates.

  19. Pre-test geological and geochemical evaluation of the Caprock, St. Peter Sandstone and formation fluids, Yakley Field, Pike County, Illinois

    SciTech Connect

    Not Available

    1983-03-01

    The goal of these studies is to ensure long-term stable containment of air in the underground reservoirs used in conjunction with compressed air energy storage (CAES) plants. The specific objective is to develop stability criteria and engineering guidelines for designing CAES reservoirs in each of the three major reservoir types, including aquifers, salt cavities, and mined hard rock caverns. This document characterizes the geologic nature of porous media constituents native to the aquifer field test site near Pittsfield, Illinois. The geologic samples were subjected to geochemical evaluations to determine anticipated responses to cyclic air injection, heating and moisture - conditions typical of an operating CAES reservoir. This report documents the procedures used and results obtained from these analyses.

  20. Applications of TOUGH2 to infiltration of liquids in media with strong heterogeneity

    SciTech Connect

    Pruess, K.; Antunez, E.

    1995-02-01

    Much hydrogeological research during the last decade has focused on the heterogeneity of natural geologic media on different scales. Most of this work has dealt with flow and transport in single-phase, isothermal conditions. The present paper is concerned with multiphase and nonisothermal flows in strongly heterogeneous media. A primary driver of our studies is the hydrogeological system at Yucca Mountain, which is currently being evaluated by the Department of Energy for its suitability as the site of the first geologic repository for civilian high-level nuclear wastes in the US Yucca Mountain is located in the and Southwest, near the Nevada-California border. Going from large scale to small, formation heterogeneities at Yucca Mountain include (i) alternating tilting layers of welded and non-welded tuffs with different matrix permeability and variable degree of fracturing, (ii) major fault systems, (iii) well-connected and permeable fracture networks in low-permeability rocks, and (iv) individual fractures with highly variable apertures.

  1. Structural Geology Personal Computers

    E-print Network

    Cattin, Rodolphe

    Structural Geology and Personal Computers #12;Struetura1 Geology and Personal Computers Edited of Congress. British Library Cataloguing in Publication Data Structural geology and personal computers. Furthermore, a 167 #12;Structural Geology and Personal Computers classification ofmantle textures and related

  2. Preliminary Mariner 9 report on the geology of Mars.

    NASA Technical Reports Server (NTRS)

    Mccauley, J. F.; Carr, M. H.; Masursky, H.; Milton, D. J.; Wilhelms, D. E.; Cutts, J. A.; Hartmann, W. K.; Sharp, R. P.

    1972-01-01

    Mariner 9 results indicate that Mars is geologically far more heterogeneous than previously suspected from earlier flyby missions; the surface has been shaped by volcanic, tectonic, erosional, and depositional activity. The equatorial region between 30 deg N and 30 deg S latitude is depicted in four geologic sketch maps, and seventeen geologic units are defined on the basis of their textural characteristics. The maps and the brief descriptions of geological units portrayed are followed by a series of more interpretive discussions dealing with topical problems and a summary geologic history. Topics covered include cratering, circular basins, volcanism, canyons, chaotic terrain, channels, and eolian activity.

  3. GEOLOGY, B.S.G. GEOLOGY OPTION

    E-print Network

    Hamburger, Peter

    GEOLOGY, B.S.G. GEOLOGY OPTION (Fall 2015-Summer 2016) IPFW Residency Requirements: ____ 32 credits GEOLOGY BSG CORE COURSES (66 credits) *Note: grades of C- or better required in GEOL courses/2.0 GPA ______ 3 - 5 Credits in Geology or Geography with Laboratory (Select 1 of the following): ___3 GEOL G103

  4. Geologic nozzles

    NASA Astrophysics Data System (ADS)

    Kieffer, Susan Werner

    Sonic velocities of geologic fluids, such as volcanic magmas and geothermal fluids, can be as low as 1 m/s. Critical velocities in large rivers can be of the order of 1-10 m/s. Because velocities of fluids moving in these settings can exceed these characteristic velocities, sonic and supersonic gas flow and critical and supercritical shallow-water flow can occur. The importance of the low characteristic velocities of geologic fluids has not been widely recognized and, as a result, the importance of supercritical and supersonic flow in geological processes has generally been underestimated. The lateral blast at Mount St. Helens, Washington, propelled a gas heavily laden with dust into the atmosphere. Because of the low sound speed in this gas (about 100 m/s), the flow was internally supersonic. Old Faithful Geyser, Wyoming, is a converging-diverging nozzle in which liquid water refilling the conduit during the recharge cycle changes during eruption into a two-phase liquid-vapor mixture with a very low sound velocity. The high sound speed of liquid water determines the characteristics of harmonic tremor observed at the geyser during the recharge interval, whereas the low sound speed of the liquid-vapor mixture influences the fluid-flow characteristics of the eruption. At the rapids of the Colorado River in the Grand Canyon, Arizona, supercritical flow occurs where debris discharged from tributary canyons constricts the channel into the shape of a converging-diverging nozzle. The geometry of the channel in these regions can be used to interpret the flood history of the Colorado River over the past 103-105 years. The unity of fluid mechanics in these three natural phenomena is provided by the well-known analogy between gas flow and shallow-water flow in converging-diverging nozzles.

  5. Geologic Nozzles

    NASA Astrophysics Data System (ADS)

    Kieffer, Susan Werner

    1989-02-01

    Sonic velocities of geologic fluids, such as volcanic magmas and geothermal fluids, can be as low as 1 m/s. Critical velocities in large rivers can be of the order of 1-10 m/s. Because velocities of fluids moving in these settings can exceed these characteristic velocities, sonic and supersonic gas flow and critical and supercritical shallow-water flow can occur. The importance of the low characteristic velocities of geologic fluids has not been widely recognized, and as a result, the importance of supercritical and supersonic flow in geological processes has generally been underestimated. The lateral blast at Mount St. Helens, Washington, propelled a gas heavily laden with dust into the atmosphere. Because of the low sound speed in this gas (about 100 m/s), the flow was internally supersonic. Old Faithful Geyser, Wyoming, is a converging-diverging nozzle in which liquid water refilling the conduit during the recharge cycle changes during eruption into a two-phase liquid-vapor mixture with a very low sound velocity. The high sound speed of liquid water determines the characteristics of harmonic tremor observed at the gyeser during the recharge interval, whereas the low sound speed of the liquid-vapor mixture influences the fluid flow characteristics of the eruption. At the rapids of the Colorado River in the Grand Canyon, Arizona, the channel is constricted into the shape of a converging-diverging nozzle by debris flows that enter from tributary canyons. Both subcritical and supercritical flow occur within the rapids. The transport capacity in the rapids can be so great that the river contours the channel to a characteristic shape. This shape can be used to interpret the flood history of the Colorado River over the past 10³-105 years. The unity of fluid mechanics in these three natural phenomena is provided by the well-known analogy between gas flow and shallow-water flow in converging-diverging nozzles.

  6. Method of Analysis by the U.S. Geological Survey California District Sacramento Laboratory?Determination of Trihalomethane Formation Potential, Method Validation, and Quality-Control Practices

    USGS Publications Warehouse

    Crepeau, Kathryn L.; Fram, Miranda S.; Bush, Noel

    2004-01-01

    An analytical method for the determination of the trihalomethane formation potential of water samples has been developed. The trihalomethane formation potential is measured by dosing samples with chlorine under specified conditions of pH, temperature, incubation time, darkness, and residual-free chlorine, and then analyzing the resulting trihalomethanes by purge and trap/gas chromatography equipped with an electron capture detector. Detailed explanations of the method and quality-control practices are provided. Method validation experiments showed that the trihalomethane formation potential varies as a function of time between sample collection and analysis, residual-free chlorine concentration, method of sample dilution, and the concentration of bromide in the sample.

  7. Geologic mapping of Vesta

    NASA Astrophysics Data System (ADS)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-11-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High-Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were emplaced; these lie stratigraphically above the equatorial ridges that likely were formed by Rheasilvia. The last features to be formed were craters with bright rays and other surface mantling deposits. Executed progressively throughout data acquisition, the iterative mapping process provided the team with geologic proto-units in a timely manner. However, interpretation of the resulting map was hampered by the necessity to provide the team with a standard nomenclature and symbology early in the process. With regard to mapping and interpreting units, the mapping process was hindered by the lack of calibrated mineralogic information. Topography and shadow played an important role in discriminating features and terrains, especially in the early stages of data acquisition.

  8. Geologic Mapping of Vesta

    NASA Technical Reports Server (NTRS)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-01-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High- Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were emplaced; these lie stratigraphically above the equatorial ridges that likely were formed by Rheasilvia. The last features to be formed were craters with bright rays and other surface mantling deposits. Executed progressively throughout data acquisition, the iterative mapping process provided the team with geologic proto-units in a timely manner. However, interpretation of the resulting map was hampered by the necessity to provide the team with a standard nomenclature and symbology early in the process. With regard to mapping and interpreting units, the mapping process was hindered by the lack of calibrated mineralogic information. Topography and shadow played an important role in discriminating features and terrains, especially in the early stages of data acquisition.

  9. Co2 geological sequestration

    SciTech Connect

    Xu, Tianfu

    2004-11-18

    Human activities are increasingly altering the Earth's climate. A particular concern is that atmospheric concentrations of carbon dioxide (CO{sub 2}) may be rising fast because of increased industrialization. CO{sub 2} is a so-called ''greenhouse gas'' that traps infrared radiation and may contribute to global warming. Scientists project that greenhouse gases such as CO{sub 2} will make the arctic warmer, which would melt glaciers and raise sea levels. Evidence suggests that climate change may already have begun to affect ecosystems and wildlife around the world. Some animal species are moving from one habitat to another to adapt to warmer temperatures. Future warming is likely to exceed the ability of many species to migrate or adjust. Human production of CO{sub 2} from fossil fuels (such as at coal-fired power plants) is not likely to slow down soon. It is urgent to find somewhere besides the atmosphere to put these increased levels of CO{sub 2}. Sequestration in the ocean and in soils and forests are possibilities, but another option, sequestration in geological formations, may also be an important solution. Such formations could include depleted oil and gas reservoirs, unmineable coal seams, and deep saline aquifers. In many cases, injection of CO2 into a geological formation can enhance the recovery of hydrocarbons, providing value-added byproducts that can offset the cost of CO{sub 2} capture and sequestration. Before CO{sub 2} gas can be sequestered from power plants and other point sources, it must be captured. CO{sub 2} is also routinely separated and captured as a by-product from industrial processes such as synthetic ammonia production, H{sub 2} production, and limestone calcination. Then CO{sub 2} must be compressed into liquid form and transported to the geological sequestration site. Many power plants and other large emitters of CO{sub 2} are located near geological formations that are amenable to CO{sub 2} sequestration.

  10. Briefing on geological sequestration (Tulsa)

    EPA Science Inventory

    Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media – primarily saline formations, depleted or nearly depleted oil and gas...

  11. IMPACTS OF ANTHROPOGENIC EMISSIONS IN THE SOUTHEASTERN U.S. ON HETEROGENEOUS CHEMISTRY OF ISOPRENE-DERIVED EPOXIDES LEADING TO SECONDARY ORGANIC AEROSOL FORMATION

    EPA Science Inventory

    The proposed activities will yield the formulation of parameterizations that can be incorporated into SOA models that will lead to improvement in the ability to simulate isoprene SOA formation in the southeastern U. S. Specific results include: (1) characterization of reaction...

  12. WESTERN PALESTINE. PHYSICAL GEOLOGY AND GEOGRAPHY

    E-print Network

    McKay, Brendan

    .' '/ SURVEY ()~. .., . / ~:. WESTERN PALESTINE. MEMOIR ON THE PHYSICAL GEOLOGY AND GEOGRAPHY ARABIA PETlUEA, PALESTINE, AND ADJOINING DISTRICTS. WITH SPECIAL REFERENCE TO THE MODE OF FORMATION. , ........' .'. ....' ,......-.. " '. .... ..... ... . .-.. .'. .' ......,.. .... ',. '. ". . ... .-.- ... .....-.: : :. -. : ~: ...:: -. :.. : .. : :.; : .. :. \\ :. : PUBLISHED FOR THE COMMITTEE OF THE PALESTINE EXPLORATION FUND I, ADAM STREET, ADELPHI. 1886

  13. Lagrangian characterization of contaminant transport through multidimensional heterogeneous media with limited heterogeneity information

    E-print Network

    Meerschaert, Mark M.

    . [2001]: ( )tXCD t tXC M , ),( +-= -1 H V , (1) MODFLOW and More 2006: Managing Ground-Water depositional or structural geologic environment; and 2) channeling along preferential flow paths. Simulating the need to explicitly define local-scale heterogeneity in a numerical model. We apply the new techniques

  14. A Handbook for Geology Students Why study Geology?.............................................................................................3

    E-print Network

    Thaxton, Christopher S.

    1 A Handbook for Geology Students #12;2 Contents Why study Geology ..................................................................................7 Why Appalachian Geology?................................................................................10 Geology Faculty and Staff

  15. Geological modeling for methane hydrate reservoir characterization in the eastern Nankai Trough, offshore Japan

    NASA Astrophysics Data System (ADS)

    Tamaki, M.; Komatsu, Y.; Suzuki, K.; Takayama, T.; Fujii, T.

    2012-12-01

    The eastern Nankai trough, which is located offshore of central Japan, is considered as an attractive potential resource field of methane hydrates. Japan Oil, Gas and Metals National Corporation is planning to conduct a production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough. The depositional environment of methane hydrate-bearing sediments around the production test site is a deep submarine-fan turbidite system, and it is considered that the reservoir properties should show lateral as well as vertical heterogeneity. Since the variations in the reservoir heterogeneity have an impact on the methane hydrate dissociation and gas production performance, precise geological models describing reservoir heterogeneity would be required for the evaluation of reservoir potentials. In preparation for the production test, 3 wells; two monitoring boreholes (AT1-MC and AT1-MT1) and a coring well (AT1-C), were newly acquired in 2012. In addition to a geotechnical hole drilling survey in 2011 (AT1-GT), totally log data from 2 wells and core data from 2 wells were obtained around the production test site. In this study, we conducted well correlations between AT1 and A1 wells drilled in 2003 and then, 3D geological models were updated including AT1 well data in order to refine hydrate reservoir characterization around the production test site. The results of the well correlations show that turbidite sand layers are characterized by good lateral continuity, and give significant information for the distribution morphology of sand-rich channel fills. We also reviewed previously conducted 3D geological models which consist of facies distributions and petrophysical properties distributions constructed from integration of 3D seismic data and a well data (A1 site) adopting a geostatistical approach. In order to test the practical validity of the previously generated models, cross-validation was conducted using AT1 well data. The results show that geological modeling including AT1 well data is important to reduce the uncertainty of the reservoir properties around the production test site. The geological models including AT1 well data were constructed taking into account for the lateral continuity of turbidite formations based on the well correlations. The concepts of these models are considered to be much more effective for describing reservoir continuity and heterogeneity and predicting upcoming production tests.

  16. Preliminary Safety Analysis of the Gorleben Site: Thermo-mechanical Analysis of the Integrity of the Geological Barrier in the Gorleben Salt Formation - 13307

    SciTech Connect

    Eickemeier, R.; Heusermann, S.; Nipp, H.K.; Knauth, M.; Minkley, W.; Popp, T.

    2013-07-01

    Exploration work at the Gorleben salt dome has been carried out since 1977 to investigate the site regarding its suitability as a final repository for high-level radioactive wastes. In the framework of the 'Preliminary Safety Analysis of the Gorleben Site' a comprehensive assessment is being performed with focus on long-term safety. Because the integrity of the geological barrier is crucial for protection from damage caused by ionising radiation during the post-operational phase, 2D and 3D thermo-mechanical calculations for a reference section through the salt dome were carried out, all looking at two different waste emplacement concepts: emplacement in drifts and in boreholes. The calculated stresses are the basis for evaluating the barrier integrity on the basis of the dilatancy criterion and the fluid pressure criterion. (authors)

  17. Massively parallel molecular dynamics simulation of formation of clathrate-hydrate precursors at planar water-methane interfaces: Insights into heterogeneous nucleation

    NASA Astrophysics Data System (ADS)

    English, Niall J.; Lauricella, Marco; Meloni, Simone

    2014-05-01

    The formation of methane-hydrate precursors at large planar water-methane interfaces has been studied using massively parallel molecular dynamics in systems of varying size from around 10 000 to almost 7 × 106 molecules. This process took two distinct steps. First, the concentration of solvated methane clusters increases just inside the aqueous domain via slow diffusion from the methane-water interface, forming "clusters" of solvated methane molecules. Second, the re-ordering process of solvated methane and water molecules takes place in a manner very roughly consistent with the "blob" hypothesis, although with important differences, to form hydrate precursors, necessary for subsequent hydrate nucleation and crystallisation. It was found that larger system sizes serve to promote the formation rate of precursors.

  18. Biochemical evolution III: Polymerization on organophilic silica-rich surfaces, crystal–chemical modeling, formation of first cells, and geological clues

    PubMed Central

    Smith, Joseph V.; Arnold, Frederick P.; Parsons, Ian; Lee, Martin R.

    1999-01-01

    Catalysis at organophilic silica-rich surfaces of zeolites and feldspars might generate replicating biopolymers from simple chemicals supplied by meteorites, volcanic gases, and other geological sources. Crystal–chemical modeling yielded packings for amino acids neatly encapsulated in 10-ring channels of the molecular sieve silicalite-ZSM-5-(mutinaite). Calculation of binding and activation energies for catalytic assembly into polymers is progressing for a chemical composition with one catalytic Al–OH site per 25 neutral Si tetrahedral sites. Internal channel intersections and external terminations provide special stereochemical features suitable for complex organic species. Polymer migration along nano/micrometer channels of ancient weathered feldspars, plus exploitation of phosphorus and various transition metals in entrapped apatite and other microminerals, might have generated complexes of replicating catalytic biomolecules, leading to primitive cellular organisms. The first cell wall might have been an internal mineral surface, from which the cell developed a protective biological cap emerging into a nutrient-rich “soup.” Ultimately, the biological cap might have expanded into a complete cell wall, allowing mobility and colonization of energy-rich challenging environments. Electron microscopy of honeycomb channels inside weathered feldspars of the Shap granite (northwest England) has revealed modern bacteria, perhaps indicative of Archean ones. All known early rocks were metamorphosed too highly during geologic time to permit simple survival of large-pore zeolites, honeycombed feldspar, and encapsulated species. Possible microscopic clues to the proposed mineral adsorbents/catalysts are discussed for planning of systematic study of black cherts from weakly metamorphosed Archaean sediments. PMID:10097060

  19. PHYSICAL GEOLOGY LABORATORY MANUAL

    E-print Network

    Merguerian, Charles

    PHYSICAL GEOLOGY LABORATORY MANUAL Geology 001 Eleventh Edition by Professors Charles Merguerian and J Bret Bennington Department of Geology Hofstra University © 2010 #12;ii Table of Contents Lab and Find Out More about Geology at Hofstra Email: Geology professors can be contacted via Email: Full

  20. Mineralization and other geologic factors related to the Morrison Formation in particular the northern two-thirds of the Colorado Plateau region; basic data and factor-analysis results

    USGS Publications Warehouse

    Cadigan, Robert Allen

    1982-01-01

    A vanadium-mercury mineralization factor and five other significant geologic factors were determined by multivariate factor analysis of data for Morrison Formation rock samples from the Colorado Plateau region. The data presented in the report were obtained from an agglomeration of 876 samples which yielded a correlation matrix of 44 variables. The variables consisted of geochemical, petrographic, and geographic location parameters. Mineralization factor scores demonstrate the relative intensity of mineralization in rock samples collected in and around uranium-vanadium ore deposits. The factors affecting composition and texture of the rocks identified from the analysis are: (1) metalliferous mudstones; (2) interstitial carbonate cements; (3) competing sources of different composition; (4) heavy mineral sources; (5) vanadium mineralization; and (6) regional and stratigraphic sampling bias.

  1. Geologic Sequestration of Carbon Dioxide

    NASA Astrophysics Data System (ADS)

    Benson, S. M.

    2003-04-01

    Geologic sequestration of carbon dioxide has emerged as one of the most promising options for making deep cuts in carbon dioxide emissions. Geologic sequestration involves the two-step process of first capturing carbon dioxide by separating it from stack emissions, followed by injection and long term storage in deep geologic formations. Sedimentary basins, including depleted oil and gas reservoirs, deep unminable coal seams, and brine-filled formations, provide the most attractive storage reservoirs. Over the past few years significant advances have been made in this technology, including development of simulation models and monitoring systems, implementation of commercial scale demonstration projects, and investigation of natural and industrial analogues for geologic storage of carbon dioxide. While much has been accomplished in a short time, there are many questions that must be answered before this technology can be employed on the scale needed to make significant reductions in carbon dioxide emissions. Questions such as how long must the carbon dioxide remain underground, to what extent will geochemical reactions completely immobilize the carbon dioxide, what can be done in the event that a storage site begins to leak at an unacceptable rate, what is the appropriate risk assessment, regulatory and legal framework, and will the public view this option favorably? This paper will present recent advances in the scientific and technological underpinnings of geologic sequestration and identify areas where additional information is needed.

  2. GO2OGS 1.0: a versatile workflow to integrate complex geological information with fault data into numerical simulation models

    NASA Astrophysics Data System (ADS)

    Fischer, T.; Naumov, D.; Sattler, S.; Kolditz, O.; Walther, M.

    2015-11-01

    We offer a versatile workflow to convert geological models built with the ParadigmTM GOCAD© (Geological Object Computer Aided Design) software into the open-source VTU (Visualization Toolkit unstructured grid) format for usage in numerical simulation models. Tackling relevant scientific questions or engineering tasks often involves multidisciplinary approaches. Conversion workflows are needed as a way of communication between the diverse tools of the various disciplines. Our approach offers an open-source, platform-independent, robust, and comprehensible method that is potentially useful for a multitude of environmental studies. With two application examples in the Thuringian Syncline, we show how a heterogeneous geological GOCAD model including multiple layers and faults can be used for numerical groundwater flow modeling, in our case employing the OpenGeoSys open-source numerical toolbox for groundwater flow simulations. The presented workflow offers the chance to incorporate increasingly detailed data, utilizing the growing availability of computational power to simulate numerical models.

  3. Geologic structure and altitude of the top of the Minnelusa Formation, northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming

    USGS Publications Warehouse

    Peter, Kathy D.; Kyllonen, David P.; Mills, K.R.

    1987-01-01

    Beginning in 1981, a 3-yr project was conducted to determine the availability and quality of groundwater in the sedimentary bedrock aquifers in the Black Hills of South Dakota and Wyoming. The project was limited to three bedrock units in order of increasing age: the Cretaceous Inyan kara Group, Permian and Pennsylvanian Minnelusa Formation, and Mississippian Madison (or Pahasapa) Limestone. This map shows the altitude of the top of the Minnelusa Formation in the northern Black Hills, and shows the configuration of the structural features in the northern part of the Black Hills and the eastern part of the Bear Lodge Mountains. In general, the Minnelusa Formation dips away from the Black Hills uplift, either to the northeast and the Williston Basin or, south of the Bear Lodge Mountains, to the southwest and the Powder River basin, which is outside the map area. In the map area, the upper beds of the Minnelusa Formation are an aquifer and the lower beds are a confining or semi-confining unit. The upper part of the Minnelusa Formation has a greater percentage of coarse-grained sandstone beds than the lower part. Furthermore, solution and removal of anhydrite, brecciation, and solution of cement binding the sandstone grains may have increased the permeability of the upper part of the Minnelusa Formation in the Black Hills. Wells completed in the upper part of the Minnelusa have yields that exceed 100 gal/min in some areas and at least one large diameter well is reported to flow 1,000 gal/min in some areas and at least one large diameter well is reported to flow 1,000 gal/min. Flowing wells have been completed in the Minnelusa aquifer in most of the study area in South Dakota and in about the northern one-half of Crook County, Wyoming. (Lantz-PTT)

  4. Coal geology of the Paleocene-Eocene Calvert Bluff Formation (Wilcox Group) and the Eocene Manning Formation (Jackson Group) in east-central Texas; field trip guidebook for the Society for Organic Petrology, Twelfth Annual Meeting, The Woodlands, Texas, August 30, 1995

    USGS Publications Warehouse

    Warwick, Peter D.; Crowley, Sharon S.

    1995-01-01

    The Jackson and Wilcox Groups of eastern Texas (fig. 1) are the major lignite producing intervals in the Gulf Region. Within these groups, the major lignite-producing formations are the Paleocene-Eocene Calvert Bluff Formation (Wilcox) and the Eocene Manning Formation (Jackson). According to the Keystone Coal Industry Manual (Maclean Hunter Publishing Company, 1994), the Gulf Coast basin produces about 57 million short tons of lignite annually. The state of Texas ranks number 6 in coal production in the United States. Most of the lignite is used for electric power generation in mine-mouth power plant facilities. In recent years, particular interest has been given to lignite quality and the distribution and concentration of about a dozen trace elements that have been identified as potential hazardous air pollutants (HAPs) by the 1990 Clean Air Act Amendments. As pointed out by Oman and Finkelman (1994), Gulf Coast lignite deposits have elevated concentrations of many of the HAPs elements (Be, Cd, Co, Cr, Hg, Mn, Se, U) on a as-received gm/mmBtu basis when compared to other United States coal deposits used for fuel in thermo-electric power plants. Although regulations have not yet been established for acceptable emissions of the HAPs elements during coal burning, considerable research effort has been given to the characterization of these elements in coal feed stocks. The general purpose of the present field trip and of the accompanying collection of papers is to investigate how various aspects of east Texas lignite geology might collectively influence the quality of the lignite fuel. We hope that this collection of papers will help future researchers understand the complex, multifaceted interrelations of coal geology, petrology, palynology and coal quality, and that this introduction to the geology of the lignite deposits of east Texas might serve as a stimulus for new ideas to be applied to other coal basins in the U.S. and abroad.

  5. Verification of geological/engineering model in waterflood areas

    SciTech Connect

    Sharma, B.; Szpakiewicz, M.; Honarpour, M.; Schatzinger, R.A.; Tillman, R.

    1988-12-01

    The construction of a detailed geological/engineering model is the basis for development of the methodology for characterizing reservoir heterogeneity. The NIPER geological/engineering model is the subject of this report. The area selected for geological and production performance studies is a four-section area within the Powder River Basin which includes the Tertiary Incentive Project (TIP) pilot. Log, well test, production, and core data were acquired for construction of the geological model of a barrier island reservoir. In this investigation, emphasis was on the synthesis and quantification of the abundant geological information acquired from the literature and field studies (subsurface and outcrop) by mapping the geological heterogeneities that influence fluid flow. The geological model was verified by comparing it with the exceptionally complete production data available for Bell Creek field. This integration of new and existing information from various geological, geophysical, and engineering disciplines has enabled better definition of the heterogeneities that influence production during different recovery operations. 16 refs., 26 figs., 6 tabs.

  6. The Necessity of Geologic Disposal

    SciTech Connect

    R. Linden

    2004-07-01

    Nuclear wastes are the radioactive byproducts of nuclear power generation, nuclear weapons production, and other uses of nuclear material. Experts from around the world agree that deep geologic disposal of nuclear waste in a mined repository is the most environmentally sound means of removing these potential sources of radiation from interaction with the biosphere. Of the 360 millirem of background radiation received annually by the average American, from both natural and man-made sources, less than 1 millirem results from the nuclear fuel cycle. Spent nuclear fuel and high-level radioactive waste, destined for geologic disposal, are located at 126 sites in 39 states. The proposed repository site at Yucca Mountain, Nevada, is far more isolated from the general population than any sites where these radioactive materials are presently located. Only solid forms of high-level wastes will be transported for disposal in a geologic repository. For more than 50 years, nuclear materials have been safely transported in North America, Europe, and Asia, without a single significant radiation release. Since the 1950s, select panels from the National Academy of Sciences-National Research Council and interagency advisory groups, and international experts selected by the OECD/Nuclear Energy Agency, have examined the environmental, ethical, and intergenerational aspects of nuclear waste disposal, plus alternatives to geologic disposal. All have concluded that deep geologic disposal in a mined repository is clearly the preferred option. The concept of deep geologic disposal is based on the analogy to ore deposits, which are formed deep within the Earth's crust, commonly remain isolated from the biosphere for millions to billions of years, and are, generally, extremely difficult to detect. Before selecting the unsaturated tuffs at Yucca Mountain, DOE evaluated salt formations, basalts, and both crystalline and sedimentary rocks. Other nations generating nuclear power also plan to use deep geologic disposal, and are evaluating sites in granites, argillaceous rocks, and salt formations.

  7. Vigorous convection in a layered, heterogeneous porous medium

    NASA Astrophysics Data System (ADS)

    Hewitt, D.; Neufeld, J. A.; Lister, J. R.

    2014-12-01

    Convective flow in a porous medium plays an important role in numerous geophysical and industrial processes, and has recently been investigated in the context of geological CO2 sequestration. Previous studies of vigorous porous convection at high Rayleigh number Ra have focused on homogeneous porous media, whereas natural porous media are often highly heterogeneous. In particular, many geological porous formations are interspersed with thin, roughly horizontal, low-permeability layers. In order to gain understanding of the interaction of low-permeability layering with convective flow, and to develop simple parameterized models of the underlying physical processes, we have performed a numerical study of high-Ra convection in a two-dimensional porous medium that contains a thin, horizontal, low-permeability interior layer. The medium is heated at the lower boundary and cooled at the upper, which sets up statistically steady convective flow throughout the domain. This archetypal system is readily applicable to compositional convection, owing to an assumption of thermal equilibrium between solid and liquid phase in the medium. We show that, in the limit that both the dimensionless thickness h and permeability ? of the low-permeability layer are small, the flow is described solely by the impedance of the layer ?= h/? and by Ra. As ? ? 0 (i.e. h ? 0), the system reduces to a homogeneous medium. We observe two notable features as ? is increased: the dominant horizontal lengthscale of the flow increases; and, surprisingly, the heat flux through the cell, as measured by the Nusselt number Nu, can increase. For larger values of ?, Nu always decreases. We explore the dependence of the flow on Ra, and develop simple theoretical models to describe some of the observed features of the relationship Nu(?). The theoretical models have implications for the simulation of convective dissolution of CO2 at reservoir scales, as heterogeneities can be much smaller than the grid scale and therefore must be parameterized.

  8. Excerpts from selected LANDSAT 1 final reports in geology

    NASA Technical Reports Server (NTRS)

    Short, N. M.; Smith, A.; Baker, R.

    1976-01-01

    The standard formats for the summaries of selected LANDSAT geological data are presented as checklists. These include: (1) value of LANDSAT data to geology, (2) geologic benefits, (3) follow up studies, (4) cost benefits, (5) optimistic working scales, (6) statistical analysis, and (7) enhancement effects.

  9. Journal of the Geological Society, London, Vol. 163, 2006, pp. 561576. Printed in Great Britain. The Pennsylvanian tropical biome reconstructed from the Joggins Formation of

    E-print Network

    Benton, Michael

    . 561 The Pennsylvanian tropical biome reconstructed from the Joggins Formation of Nova Scotia, Canada H. Brackish seas, the distal extension of European marine bands, were populated by Foraminifera, molluscs of this ancient tropical biome in detail (Scott 1977, 1998). Pennsylvanian ecosystems are among the best

  10. Geologic Technician New Curriculum

    ERIC Educational Resources Information Center

    Karp, Stanley E.

    1970-01-01

    Describes a developing two-year geologic technician program at Bakersfield College in which a student may major in five areas - geologic drafting, land and legal, geologic assistant, engineering or paleontology. (RR)

  11. SEISMIC DETERMINATION OF RESERVOIR HETEROGENEITY; APPLICATION TO THE CHARACTERIZATION OF HEAVY OIL RESERVOIRS

    SciTech Connect

    Matthias G. Imhof; James W. Castle

    2003-11-01

    The objective of the project is to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study is performed at West Coalinga Field in California. We continued our investigation on the nature of seismic reactions from heterogeneous reservoirs. We began testing our algorithm to infer parameters of object-based reservoir models from seismic data. We began integration of seismic and geologic data to determine the deterministic limits of conventional seismic data interpretation. Lastly, we began integration of seismic and geologic heterogeneity using stochastic models conditioned both on wireline and seismic data.

  12. Old Geology and New Geology

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 28 May 2003

    Mangala Vallis one of the large outflow channels that channeled large quantities of water into the northern lowlands, long ago on geological timescales. This valley is one of the few in the southern hemisphere, as well as one of the few west of the Tharsis bulge. A closer look at the channel shows more recent weathering of the old water channel: the walls of the channel show small, dark slope streaks that form in dusty areas; and much of the surrounding terrain has subtle linear markings trending from the upper left to the lower right, which are probably features sculpted and streamlined by the wind. Geology still shapes the surface of Mars today, but its methods over the eons have changed.

    Image information: VIS instrument. Latitude -6, Longitude 209.6 East (150.4 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  13. Modeling geologic storage of carbon dioxide: Comparison ofnon-hysteretic and hysteretic characteristic curves

    SciTech Connect

    Doughty, Christine

    2006-07-17

    Numerical models of geologic storage of carbon dioxide (CO2)in brine-bearing formations use characteristic curves to represent theinteractions of non-wetting-phase CO2 and wetting-phase brine. When aproblem includes both injection of CO2 (a drainage process) and itssubsequent post-injection evolution (a combination of drainage andwetting), hysteretic characteristic curves are required to correctlycapture the behavior of the CO2 plume. In the hysteretic formulation,capillary pressure and relative permeability depend not only on thecurrent grid-block saturation, but also on the history of the saturationin the grid block. For a problem that involves only drainage or onlywetting, a non-hysteretic formulation, in which capillary pressure andrelative permeability depend only on the current value of the grid-blocksaturation, is adequate. For the hysteretic formulation to be robustcomputationally, care must be taken to ensure the differentiability ofthe characteristic curves both within and beyond the turning-pointsaturations where transitions between branches of the curves occur. Twoexample problems involving geologic CO2 storage are simulated withTOUGH2, a multiphase, multicomponent code for flow and transport codethrough geological media. Both non-hysteretic and hysteretic formulationsare used, to illustrate the applicability and limitations ofnon-hysteretic methods.The first application considers leakage of CO2from the storage formation to the ground surface, while the secondexamines the role of heterogeneity within the storageformation.

  14. Ultra-deep oxidation and exotic copper formation at the late pliocene boyongan and bayugo porphyry copper-gold deposits, surigao, philippines: Geology, mineralogy, paleoaltimetry, and their implications for Geologic, physiographic, and tectonic controls

    USGS Publications Warehouse

    Braxton, D.P.; Cooke, D.R.; Ignacio, A.M.; Rye, R.O.; Waters, P.J.

    2009-01-01

    The Boyongan and Bayugo porphyry copper-gold deposits are part of an emerging belt of intrusion-centered gold-rich deposits in the Surigao district of northeast Mindanao, Philippines. Exhumation and weathering of these Late Pliocene-age deposits has led to the development of the world's deepest known porphyry oxidation profile at Boyongan (600 m), and yet only a modest (30-70 m) oxidation profile at adjacent Bayugo. Debris flows, volcanic rocks, and fluviolacustrine sediments accumulating in the actively extending Mainit graben subsequently covered the deposits and preserved the supergene profiles. At Boyongan and Bayugo, there is a vertical transition from shallower supergene copper oxide minerals (malachite + azurite + cuprite) to deeper sulfide-stable assemblages (chalcocite ?? hypogene sulfides). This transition provides a time-integrated proxy for the position of the water table at the base of the saturated zone during supergene oxidation. Contours of the elevation of the paleopotentiometric surface based on this min- eralogical transition show that the thickest portions of the unsaturated zone coincided with a silt-sand matrix diatreme breccia complex at Boyongan. Within the breccia complex, the thickness of the unsaturated zone approached 600 in, whereas outside the breccia complex (e.g., at Bayugo), the thickness averaged 50 m. Contours of the paleopotentiometric surface suggest that during weathering, groundwater flowed into the breccia complex from the north, south, and east, and exited along a high permeability zone to the west. The high relief (>550 m) on the elevation of the paleopotentiometric surface is consistent with an environment of high topographic relief, and the outflow zone to the west of the breccia complex probably reflects proximity to a steep scarp intersecting the western breccia complex margin. Stable isotope paleoaltimetry has enabled estimation of the elevation of the land surface, which further constrains the physiographic setting during supergene oxidation. Isotopic measurements of oxygen in supergene kaolinite from Boyongan suggest that local paleometeoric water involved in weathering had a ??180 composition of approximately -5.7 per mil. At the latitude of the southern Philippines, this value corresponds to Pleistocene rain water condensing at elevations between 750 and 1,050 m above contemporary sea level, providing a maximum estimate for the surface elevation during weathering of the porphyry systems. Physiographic reconstuctions suggest that the deep oxidation profile at Boyongan formed in an environment of high topographic relief immediately east of a prominent (>550 m) escarpment. The high permeability contrast between the breccia complex and the surrounding wall rocks, coupled with the proximity of the breccia complex to the escarpment, led to a depressed groundwater table and a vertically extensive unsaturated zone in the immediate vicinity of Boyongan. This thick vadose zone and the low hypogene pyrite/copper sulfide ratios (0.6) at Boyongan promoted in situ oxidation of copper sulfides with only modest (<200 m) supergene remobilization of copper. In contrast, higher hypogene pyrite/chalcopyrite ratios (2.3) at Bayugo led to greater acid production during weathering and more complete leaching of copper above the base of oxidation. This process promoted significant (600 m) lateral dispersion of copper down the paleohydraulic gradient into the diatreme breccia comple, ultimately leading to the formation of an exotic copper deposit. ?? 2009 Society of Economices Geologists, Inc.

  15. Spatial Heterogeneity of Carbonates: genetic approach

    NASA Astrophysics Data System (ADS)

    Violette, Sophie; Gonçalvès, Julio; de Marsily, Ghislain

    2010-05-01

    Homogeneous equivalent property is a classical concept used in hydrogeology to define heterogeneity of hydraulic properties. Known as averaging, it tries to describe the spatial variability of the rock properties from geologic observations and local measurements. The techniques available for these descriptions are mostly continuous Geostatistical models, or discontinuous facies models such as the Boolean, Indicator or Gaussian-Threshold models and the Markow chain model. These facies models are better suited to treating issues of rock strata connectivity, e.g. buried high permeability channels or low permeability barriers, which greatly affect flow and, above all, transport in aquifers. Genetic models provide new ways to incorporate more geology into the facies description, an approach that has been well developed in the oil industry, but not enough in hydrogeology. Here we present how a 3Dbasin model, based on a detailed stratigraphic data base, has been used in a genetic way to reproduce the permeability and storage coefficient heterogeneities at the regional scale.

  16. Visible Geology - Interactive online geologic block modelling

    NASA Astrophysics Data System (ADS)

    Cockett, R.

    2012-12-01

    Geology is a highly visual science, and many disciplines require spatial awareness and manipulation. For example, interpreting cross-sections, geologic maps, or plotting data on a stereonet all require various levels of spatial abilities. These skills are often not focused on in undergraduate geoscience curricula and many students struggle with spatial relations, manipulations, and penetrative abilities (e.g. Titus & Horsman, 2009). A newly developed program, Visible Geology, allows for students to be introduced to many geologic concepts and spatial skills in a virtual environment. Visible Geology is a web-based, three-dimensional environment where students can create and interrogate their own geologic block models. The program begins with a blank model, users then add geologic beds (with custom thickness and color) and can add geologic deformation events like tilting, folding, and faulting. Additionally, simple intrusive dikes can be modelled, as well as unconformities. Students can also explore the interaction of geology with topography by drawing elevation contours to produce their own topographic models. Students can not only spatially manipulate their model, but can create cross-sections and boreholes to practice their visual penetrative abilities. Visible Geology is easy to access and use, with no downloads required, so it can be incorporated into current, paper-based, lab activities. Sample learning activities are being developed that target introductory and structural geology curricula with learning objectives such as relative geologic history, fault characterization, apparent dip and thickness, interference folding, and stereonet interpretation. Visible Geology provides a richly interactive, and immersive environment for students to explore geologic concepts and practice their spatial skills.; Screenshot of Visible Geology showing folding and faulting interactions on a ridge topography.

  17. Prototype of Partial Cutting Tool of Geological Map Images Distributed by Geological Web Map Service

    NASA Astrophysics Data System (ADS)

    Nonogaki, S.; Nemoto, T.

    2014-12-01

    Geological maps and topographical maps play an important role in disaster assessment, resource management, and environmental preservation. These map information have been distributed in accordance with Web services standards such as Web Map Service (WMS) and Web Map Tile Service (WMTS) recently. In this study, a partial cutting tool of geological map images distributed by geological WMTS was implemented with Free and Open Source Software. The tool mainly consists of two functions: display function and cutting function. The former function was implemented using OpenLayers. The latter function was implemented using Geospatial Data Abstraction Library (GDAL). All other small functions were implemented by PHP and Python. As a result, this tool allows not only displaying WMTS layer on web browser but also generating a geological map image of intended area and zoom level. At this moment, available WTMS layers are limited to the ones distributed by WMTS for the Seamless Digital Geological Map of Japan. The geological map image can be saved as GeoTIFF format and WebGL format. GeoTIFF is one of the georeferenced raster formats that is available in many kinds of Geographical Information System. WebGL is useful for confirming a relationship between geology and geography in 3D. In conclusion, the partial cutting tool developed in this study would contribute to create better conditions for promoting utilization of geological information. Future work is to increase the number of available WMTS layers and the types of output file format.

  18. Simulation of CO2 Sequestration at Rock Spring Uplift, Wyoming: Heterogeneity and Uncertainties in Storage Capacity, Injectivity and Leakage

    SciTech Connect

    Deng, Hailin; Dai, Zhenxue; Jiao, Zunsheng; Stauffer, Philip H.; Surdam, Ronald C.

    2011-01-01

    Many geological, geochemical, geomechanical and hydrogeological factors control CO{sub 2} storage in subsurface. Among them heterogeneity in saline aquifer can seriously influence design of injection wells, CO{sub 2} injection rate, CO{sub 2} plume migration, storage capacity, and potential leakage and risk assessment. This study applies indicator geostatistics, transition probability and Markov chain model at the Rock Springs Uplift, Wyoming generating facies-based heterogeneous fields for porosity and permeability in target saline aquifer (Pennsylvanian Weber sandstone) and surrounding rocks (Phosphoria, Madison and cap-rock Chugwater). A multiphase flow simulator FEHM is then used to model injection of CO{sub 2} into the target saline aquifer involving field-scale heterogeneity. The results reveal that (1) CO{sub 2} injection rates in different injection wells significantly change with local permeability distributions; (2) brine production rates in different pumping wells are also significantly impacted by the spatial heterogeneity in permeability; (3) liquid pressure evolution during and after CO{sub 2} injection in saline aquifer varies greatly for different realizations of random permeability fields, and this has potential important effects on hydraulic fracturing of the reservoir rock, reactivation of pre-existing faults and the integrity of the cap-rock; (4) CO{sub 2} storage capacity estimate for Rock Springs Uplift is 6614 {+-} 256 Mt at 95% confidence interval, which is about 36% of previous estimate based on homogeneous and isotropic storage formation; (5) density profiles show that the density of injected CO{sub 2} below 3 km is close to that of the ambient brine with given geothermal gradient and brine concentration, which indicates CO{sub 2} plume can sink to the deep before reaching thermal equilibrium with brine. Finally, we present uncertainty analysis of CO{sub 2} leakage into overlying formations due to heterogeneity in both the target saline aquifer and surrounding formations. This uncertainty in leakage will be used to feed into risk assessment modeling.

  19. Development plus kinetic and mechanistic studies of a prototype supported-nanoparticle heterogeneous catalyst formation system in contact with solution: Ir(1,5-COD)Cl/gamma-Al2O3 and its reduction by H2 to Ir(0)n/gamma-Al2O3.

    PubMed

    Mondloch, Joseph E; Wang, Qi; Frenkel, Anatoly I; Finke, Richard G

    2010-07-21

    An important question and hence goal in catalysis is how best to transfer the synthetic and mechanistic insights gained from the modern revolution in nanoparticle synthesis, characterization, and catalysis to prepare the next generation of improved, supported-nanoparticle heterogeneous catalysts. It is precisely this question and to-date somewhat elusive goal which are addressed by the present work. More specifically, the global hypothesis investigated herein is that the use of speciation-controlled, well-characterized, solid oxide supported-organometallic precatalysts in contact with solution will lead to the next generation of better composition, size- and shape-controlled, as well as highly active and reproducible, supported-nanoparticle heterogeneous catalysts-ones that can also be understood kinetically and mechanistically. Developed herein are eight criteria defining a prototype system for supported-nanoparticle heterogeneous catalyst formation in contact with solution. The initial prototype system explored is the precatalyst, Ir(1,5-COD)Cl/gamma-Al(2)O(3) (characterized via ICP, CO adsorption, IR, and XAFS spectroscopies), and the well-defined product, Ir(0)(n)/gamma-Al(2)O(3) (characterized by reaction stoichiometry, TEM, and XAFS). The Ir(0)(n)/gamma-Al(2)O(3) system proved to be a highly active and long-lived catalyst in the simple test reaction of cyclohexene hydrogenation and in comparison to two literature Ir(0)(n)/Al(2)O(3) heterogeneous catalysts examined under identical conditions. High activity (2.2-4.8-fold higher than that of the literature Ir(0)(n)/Al(2)O(3) catalysts tested under the same conditions) and good lifetime (> or = 220,000 total turnovers of cyclohexene hydrogenation) are observed, in part by design since only acetone solvent, cyclohexene, and H(2) are possible ligands in the resultant "weakly ligated/labile-ligand" supported nanoclusters. Significantly, the Ir(1,5-COD)Cl/gamma-Al(2)O(3) + H(2) --> Ir(0)(n)/gamma-Al(2)O(3) heterogeneous catalyst formation kinetics were also successfully monitored using the cyclohexene hydrogenation reporter reaction method previously developed and applied to solution-nanoparticle formation. The observed sigmoidal supported-nanoparticle heterogeneous catalyst formation kinetics, starting from the Ir(1,5-COD)Cl/gamma-Al(2)O(3) precatalyst, are closely fit by the two-step mechanism of slow continuous nucleation (A --> B, rate constant k(1) = 1.5(1.1) x 10(-3) h(-1)) followed by fast autocatalytic surface growth (A + B --> 2B, rate constant k(2) = 1.6(2) x 10(4) h(-1) M(-1)), where A is the Ir(1,5-COD)Cl/gamma-Al(2)O(3) precatalyst and B is the resultant Ir(0)(n)/gamma-Al(2)O(3) catalyst. The kinetics are significant in establishing the ability to monitor the formation of supported-nanoparticle heterogeneous catalysts in contact with solution. They also suggest that the nine synthetic and mechanistic insights from the two-step mechanism of nanoparticle formation in solution should now apply also to the formation of supported-nanoparticle heterogeneous catalysts in contact with solution. The results open the door for new syntheses of supported-nanoparticle heterogeneous catalysts under nontraditional, mild, and flexible conditions where supported organometallics and other precursors are in contact with solution, so that additional variables such as the solvent choice, added ligands, solution temperature, and so on can be used to control the catalyst formation steps and, ideally, the resultant supported-nanoparticle heterogeneous catalyst composition, size, and shape. PMID:20575521

  20. GO2OGS: a versatile workflow to integrate complex geological information with fault data into numerical simulation models

    NASA Astrophysics Data System (ADS)

    Fischer, T.; Walther, M.; Sattler, S.; Naumov, D.; Kolditz, O.

    2015-08-01

    We offer a versatile workflow to convert geological models built with the software Paradigm™ GOCAD© into the open-source VTU format for the usage in numerical simulation models. Tackling relevant scientific questions or engineering tasks often involves multidisciplinary approaches. Conversion workflows are needed as a way of communication between the diverse tools of the various disciplines. Our approach offers an open-source, platform independent, robust, and comprehensible method that is potentially useful for a multitude of similar environmental studies. With two application examples in the Thuringian Syncline, we show how a heterogeneous geological GOCAD model including multiple layers and faults can be used for numerical groundwater flow modelling. The presented workflow offers the chance to incorporate increasingly detailed data, utilizing growing availability of computational power to simulate numerical models.

  1. Marine geology: A planet earth perspective

    SciTech Connect

    Anderson, R.N.

    1986-01-01

    This text provides coverage of the basic geology of the marine development. It starts with the formation of the oceans using plate tectonics, continues with discussions of the mid-ocean ridges, and concludes with coverage of the formation and deformation of the continents.

  2. Predictions of long-term behavior of a large-volume pilot test for CO2 geological storage in a saline formation in the Central Valley, California

    SciTech Connect

    Doughty, Christine; Myer, Larry R.; Oldenburg, Curtis M.

    2008-11-01

    The long-term behavior of a CO{sub 2} plume injected into a deep saline formation is investigated, focusing on mechanisms that lead to plume stabilization. Key measures are plume migration distance and the time evolution of CO{sub 2} phase-partitioning, which are examined by developing a numerical model of the subsurface at a proposed power plant with CO{sub 2} capture in the San Joaquin Valley, California, where a large-volume pilot test of CO{sub 2} injection will be conducted. The numerical model simulates a four-year CO{sub 2} injection period and the subsequent evolution of the CO{sub 2} plume until it stabilizes. Sensitivity studies are carried out to investigate the effect of poorly constrained model parameters permeability, permeability anisotropy, and residual gas saturation.

  3. SIMULATION MODEL ANALYSIS OF THE MOST PROMISING GEOLOGIC SEQUESTRATION FORMATION CANDIDATES IN THE ROCKY MOUNTAIN REGION, USA, WITH FOCUS ON UNCERTAINTY ASSESSMENT

    SciTech Connect

    Lee, Si-Yong; Zaluski, Wade; Will, Robert; Eisinger, Chris; Matthews, Vince; McPherson, Brian

    2013-09-01

    The purpose of this report is to report results of reservoir model simulation analyses for forecasting subsurface CO2 storage capacity estimation for the most promising formations in the Rocky Mountain region of the USA. A particular emphasis of this project was to assess uncertainty of the simulation-based forecasts. Results illustrate how local-scale data, including well information, number of wells, and location of wells, affect storage capacity estimates and what degree of well density (number of wells over a fixed area) may be required to estimate capacity within a specified degree of confidence. A major outcome of this work was development of a new workflow of simulation analysis, accommodating the addition of “random pseudo wells” to represent virtual characterization wells.

  4. 3-D seismic delineation and geologic explanation of channelization in the Frio Formation of Javelina/East McCook Field, Hidalgo County, Texas

    SciTech Connect

    Gibson, J.L.

    1994-09-01

    Sinuous, channel-form features were recognized on seismic amplitude time-slice maps of the shallow Oligocene Frio Formation on several Shell proprietary 3-D seismic surveys in west-central Hidalgo County, Texas. A case study of channel morphologies observed in the Frio Formation within the 50 mi{sup 2} 3-D seismic survey over Javelina/East McCook field was undertaken to better understand the distribution, lithology, origin, and hydrocarbon potential of these features. Ten separate channel-like amplitude features are observed in flattened time slices within a 200 m (approximately 1100 ft) interval on 3-D seismic. The channels have various azimuthal orientations and varying degrees of sinuosity. Several of the features have lengths that span the 3-D survey area (10 mi); apparent channel widths range from 200 to 2000 ft. The channelized seismic events tie to an interval of interbedded mudstones and claystones with siltstones. Two of the channels seen on seismic, and which were penetrated by wells, correlate to siftstone and mudstone intervals that have gross thicknesses of 30 to 60 ft. The lithologies and dimensions of the two channels indicate that they are probably small mudstone/siltstone-filled tributary/distributary channels deposited in a coastal floodplain environment; a comparison of the apparent channel dimensions to the dimensions of small channels/bayous of the modern-day Texas Gulf Coast supports this interpretation. Correlation of wells adjacent to the channels indicates that sandy point-bar facies are not present in association with the channel fill, which discounts the idea that high-quality reservoirs are flanking these particular mud-filled channels.

  5. High-Resolution Characterization of Reservoir Heterogeneity and Connectivity in Clastic Environments 

    E-print Network

    Hull, Thomas Frederick

    2011-10-21

    allows for better delineation of subsurface geologic features, detailed mapping of reservoir heterogeneities and more accurate identification of depositional, structural, and stratigraphic characteristics that control reservoir connectivity and fluid flow...

  6. Seismic Determination of Reservoir Heterogeneity: Application to the Characterization of Heavy Oil Reservoirs

    SciTech Connect

    Imhof, Matthias G.; Castle, James W.

    2003-03-12

    The objective of the project was to examine how seismic and geologic data could be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study was performed at West Coalinga Field in California.

  7. Performance assessment for the geological disposal of Deep Burn spent fuel using TTBX

    SciTech Connect

    Van den Akker, B.P.; Ahn, J.

    2013-07-01

    The behavior of Deep Burn Modular High Temperature Reactor Spent Fuel (DBSF) is investigated in the Yucca Mountain geological repository (YMR) with respect to the annual dose (Sv/yr) delivered to the Reasonably Maximally Exposed Individual (RMEI) from the transport of radionuclides released from the graphite waste matrix. Transport calculations are performed with a novel computer code, TTBX which is capable of modeling transport pathways that pass through heterogeneous geological formations. TTBX is a multi-region extension of the existing single region TTB transport code. Overall the peak annual dose received by the RMEI is seen to be four orders of magnitude lower than the regulatory threshold for exposure, even under pessimistic scenarios. A number of factors contribute to the favorable performance of DBSF. A reduction of one order of magnitude in the peak annual dose received by the RMEI is observed for every order of magnitude increase in the waste matrix lifetime, highlighting the importance of the waste matrix durability and suggesting graphite's utility as a potential waste matrix for the disposal of high-level waste. Furthermore, we see that by incorporating a higher fidelity far-field model the peak annual dose calculated to be received by the RMEI is reduced by two orders of magnitude. By accounting for the heterogeneities of the far field we have simultaneously removed unnecessary conservatisms and improved the fidelity of the transport model. (authors)

  8. Significant achievements in the Planetary Geology Program. [geologic processes, comparative planetology, and solar system evolution

    NASA Technical Reports Server (NTRS)

    Head, J. W. (editor)

    1978-01-01

    Developments reported at a meeting of principal investigators for NASA's planetology geology program are summarized. Topics covered include: constraints on solar system formation; asteriods, comets, and satellites; constraints on planetary interiors; volatiles and regoliths; instrument development techniques; planetary cartography; geological and geochemical constraints on planetary evolution; fluvial processes and channel formation; volcanic processes; Eolian processes; radar studies of planetary surfaces; cratering as a process, landform, and dating method; and the Tharsis region of Mars. Activities at a planetary geology field conference on Eolian processes are reported and techniques recommended for the presentation and analysis of crater size-frequency data are included.

  9. Modeling geologic storage of carbon dioxide: Comparison ofnon-hysteretic chracteristic curves

    SciTech Connect

    Doughty, Christine

    2006-04-28

    TOUGH2 models of geologic storage of carbon dioxide (CO2) in brine-bearing formations use characteristic curves to represent the interactions of non-wetting-phase CO2 and wetting-phase brine. When a problem includes both injection of CO2 (a drainage process) and its subsequent post-injection evolution (a combination of drainage and wetting), hysteretic characteristic curves are required to correctly capture the behavior of the CO2 plume. In the hysteretic formulation, capillary pressure and relative permeability depend not only on the current grid-block saturation, but also on the history of the saturation in the grid block. For a problem that involves only drainage or only wetting, a nonhysteretic formulation, in which capillary pressure and relative permeability depend only on the current value of the grid-block saturation, is adequate. For the hysteretic formulation to be robust computationally, care must be taken to ensure the differentiability of the characteristic curves both within and beyond the turning-point saturations where transitions between branches of the curves occur. Two example problems involving geologic CO2 storage are simulated using non-hysteretic and hysteretic models, to illustrate the applicability and limitations of non-hysteretic methods: the first considers leakage of CO2 from the storage formation to the ground surface, while the second examines the role of heterogeneity within the storage formation.

  10. North Dakota geology school receives major gift

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-10-01

    Petroleum geology and related areas of study at the University of North Dakota (UND) received a huge financial boost with the announcement on 24 September of $14 million in private and public partnership funding. The university announced the naming of the Harold Hamm School of Geology and Geological Engineering, formerly a department within the College of Engineering and Mines, in recognition of $10 million provided as a gift by oilman Harold Hamm and Continental Resources, Inc. Hamm is the chair and chief executive officer of Continental, the largest leaseholder in the Bakken Play oil formation in North Dakota and Montana, and he is also an energy policy advisor to Republican presidential candidate Mitt Romney. UND also received $4 million from the Oil and Gas Research Program of the North Dakota Industrial Commission to support geology and geological engineering education and research.

  11. Evaluation of the geological relationships to gas hydrate formation and stability. Annual technical progress report, October 1, 1984--September 30, 1985

    SciTech Connect

    Not Available

    1985-12-31

    During the reported year we have enhanced our knowledge on and gained considerable experience in assessment of the gas hydrate resources in the offshore environments. Specifically, we have learned and gained experience in the following: Efficiently locating data sources, including published literature and unpublished information. We have established personal communication extremely critical in data accessability and acquisition. We have updated information pertinent to gas hydrate knowledge, also based on thorough study and evaluation of most Russian literature and additional publications in languages other than English. Besides critical evaluation of widely spread literature, in many cases our reports include previously unpublished information (e.g. BSRs from the Gulf of Mexico). The assessment of the gas resources potential associated with the gas hydrates, although in most cases at a low level of confidence, appears also very encouraging for further, more detailed, study. We are also confident that, because of the present reports` format, new data and a concept-oriented approach, the result of our study will be of strong interest to various industries, research institutions and numerous governmental agencies.

  12. Geology and paleoecology of the Cottonwood Creek delta in the Eocene Tipton Tongue of the Green River Formation and a mammalian fauna from the Eocene Cathedral Bluffs Tongue of the Wasatch Formation, Southeast Washakie Basin, Wyoming

    SciTech Connect

    Roehler, H.W.; Hanley, J.H.; Honey, J.G.

    1988-01-01

    Nonmarine mollusks are used to interpret paleoenvironments and patterns of sedimentation of a fan delta on the east margin of Eocene Lake Gosiute. The delta is composed of a lens of quartzose sandstone intertongued with oil shale. Delta morphology is illustrated by cross sections and paleogeographic maps. A fossil fauna representing five mammalian orders is described and used to establish the age of parts of the Wasatch and Green River formations. There are three chapters in this bulletin.

  13. A theoretical framework for modeling dilution enhancement of non-reactive solutes in heterogeneous porous media

    NASA Astrophysics Data System (ADS)

    de Barros, F. P. J.; Fiori, A.; Boso, F.; Bellin, A.

    2015-04-01

    Spatial heterogeneity of the hydraulic properties of geological porous formations leads to erratically shaped solute clouds, thus increasing the edge area of the solute body and augmenting the dilution rate. In this study, we provide a theoretical framework to quantify dilution of a non-reactive solute within a steady state flow as affected by the spatial variability of the hydraulic conductivity. Embracing the Lagrangian concentration framework, we obtain explicit semi-analytical expressions for the dilution index as a function of the structural parameters of the random hydraulic conductivity field, under the assumptions of uniform-in-the-average flow, small injection source and weak-to-mild heterogeneity. Results show how the dilution enhancement of the solute cloud is strongly dependent on both the statistical anisotropy ratio and the heterogeneity level of the porous medium. The explicit semi-analytical solution also captures the temporal evolution of the dilution rate; for the early- and late-time limits, the proposed solution recovers previous results from the literature, while at intermediate times it reflects the increasing interplay between large-scale advection and local-scale dispersion. The performance of the theoretical framework is verified with high resolution numerical results and successfully tested against the Cape Cod field data.

  14. A theoretical framework for modeling dilution enhancement of non-reactive solutes in heterogeneous porous media.

    PubMed

    de Barros, F P J; Fiori, A; Boso, F; Bellin, A

    2015-01-01

    Spatial heterogeneity of the hydraulic properties of geological porous formations leads to erratically shaped solute clouds, thus increasing the edge area of the solute body and augmenting the dilution rate. In this study, we provide a theoretical framework to quantify dilution of a non-reactive solute within a steady state flow as affected by the spatial variability of the hydraulic conductivity. Embracing the Lagrangian concentration framework, we obtain explicit semi-analytical expressions for the dilution index as a function of the structural parameters of the random hydraulic conductivity field, under the assumptions of uniform-in-the-average flow, small injection source and weak-to-mild heterogeneity. Results show how the dilution enhancement of the solute cloud is strongly dependent on both the statistical anisotropy ratio and the heterogeneity level of the porous medium. The explicit semi-analytical solution also captures the temporal evolution of the dilution rate; for the early- and late-time limits, the proposed solution recovers previous results from the literature, while at intermediate times it reflects the increasing interplay between large-scale advection and local-scale dispersion. The performance of the theoretical framework is verified with high resolution numerical results and successfully tested against the Cape Cod field data. PMID:25795562

  15. AN INTEGRATED VIEW OF GROUNDWATER FLOW CHARACTERIZATION AND MODELING IN FRACTURED GEOLOGIC MEDIA

    EPA Science Inventory

    The particular attributes of fractured geologic media pertaining to groundwater flow characterization and modeling are presented. These cover the issues of fracture network and hydraulic control of fracture geometry parameters, major and minor fractures, heterogeneity, anisotrop...

  16. Investigation of CO2 plume behavior for a large-scale pilot test of geologic carbon storage in a saline formation

    SciTech Connect

    Doughty, C.

    2009-04-01

    The hydrodynamic behavior of carbon dioxide (CO{sub 2}) injected into a deep saline formation is investigated, focusing on trapping mechanisms that lead to CO{sub 2} plume stabilization. A numerical model of the subsurface at a proposed power plant with CO{sub 2} capture is developed to simulate a planned pilot test, in which 1,000,000 metric tons of CO{sub 2} is injected over a four-year period, and the subsequent evolution of the CO{sub 2} plume for hundreds of years. Key measures are plume migration distance and the time evolution of the partitioning of CO{sub 2} between dissolved, immobile free-phase, and mobile free-phase forms. Model results indicate that the injected CO{sub 2} plume is effectively immobilized at 25 years. At that time, 38% of the CO{sub 2} is in dissolved form, 59% is immobile free phase, and 3% is mobile free phase. The plume footprint is roughly elliptical, and extends much farther up-dip of the injection well than down-dip. The pressure increase extends far beyond the plume footprint, but the pressure response decreases rapidly with distance from the injection well, and decays rapidly in time once injection ceases. Sensitivity studies that were carried out to investigate the effect of poorly constrained model parameters permeability, permeability anisotropy, and residual CO{sub 2} saturation indicate that small changes in properties can have a large impact on plume evolution, causing significant trade-offs between different trapping mechanisms.

  17. Volcanic geology of Tyrrhena Patera, Mars

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Crown, David, A.

    1990-01-01

    Consideration is given to the geology of Tyrrhena Patera, a large low-relief volcano in the southern cratered highlands of Mars. The general geology of Tyrrhena Patera is outlined and models for the formation of the volcano are described. Models derived from studies of terrestrial pyroclastic flows are applied to deposits at Tyrrhena Patera, showing that the characteristics of the deposits are consistent with an origin by the emplacement of gravity-driven ash flows generated by hydromagmatic or magmatic explosive eruptions.

  18. Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 10, Basin analysis, formation and stability of gas hydrates of the Aleutian Trench and the Bering Sea

    SciTech Connect

    Krason, J.; Ciesnik, M.

    1987-01-01

    Four major areas with inferred gas hydrates are the subject of this study. Two of these areas, the Navarin and the Norton Basins, are located within the Bering Sea shelf, whereas the remaining areas of the Atka Basin in the central Aleutian Trench system and the eastern Aleutian Trench represent a huge region of the Aleutian Trench-Arc system. All four areas are geologically diverse and complex. Particularly the structural features of the accretionary wedge north of the Aleutian Trench still remain the subjects of scientific debates. Prior to this study, suggested presence of the gas hydrates in the four areas was based on seismic evidence, i.e., presence of bottom simulating reflectors (BSRs). Although the disclosure of the BSRs is often difficult, particularly under the structural conditions of the Navarin and Norton basins, it can be concluded that the identified BSRs are mostly represented by relatively weak and discontinuous reflectors. Under thermal and pressure conditions favorable for gas hydrate formation, the relative scarcity of the BSRs can be attributed to insufficient gas supply to the potential gas hydrate zone. Hydrocarbon gas in sediment may have biogenic, thermogenic or mixed origin. In the four studied areas, basin analysis revealed limited biogenic hydrocarbon generation. The migration of the thermogenically derived gases is probably diminished considerably due to the widespread diagenetic processes in diatomaceous strata. The latter processes resulted in the formation of the diagenetic horizons. The identified gas hydrate-related BSRs seem to be located in the areas of increased biogenic methanogenesis and faults acting as the pathways for thermogenic hydrocarbons.

  19. Digital geologic map and GIS database of Venezuela

    USGS Publications Warehouse

    Garrity, Christopher P.; Hackley, Paul C.; Urbani, Franco

    2006-01-01

    The digital geologic map and GIS database of Venezuela captures GIS compatible geologic and hydrologic data from the 'Geologic Shaded Relief Map of Venezuela,' which was released online as U.S. Geological Survey Open-File Report 2005-1038. Digital datasets and corresponding metadata files are stored in ESRI geodatabase format; accessible via ArcGIS 9.X. Feature classes in the geodatabase include geologic unit polygons, open water polygons, coincident geologic unit linework (contacts, faults, etc.) and non-coincident geologic unit linework (folds, drainage networks, etc.). Geologic unit polygon data were attributed for age, name, and lithologic type following the Lexico Estratigrafico de Venezuela. All digital datasets were captured from source data at 1:750,000. Although users may view and analyze data at varying scales, the authors make no guarantee as to the accuracy of the data at scales larger than 1:750,000.

  20. OneGeology: Making the World’s Geological Map Data Accessible Online

    NASA Astrophysics Data System (ADS)

    Broome, H.; Jackson, I.; Robida, F.; Thorleifson, H.

    2009-12-01

    OneGeology (http://onegeology.org) is a successful international initiative of the geological surveys of the world and the flagship project of the ‘International Year of Planet Earth’. Its aim is to provide dynamic web access to geological map data covering the world, creating a focus for accessing geological information for everyone. Thanks to the enthusiasm and support of participating nations the initiative has progressed rapidly and geological surveys and the many users of their data are excited about this ground-breaking project. Currently 10 international geoscience organizations have endorsed the initiative and more than 109 countries have agreed to participate. OneGeology works with whatever digital format is available in each country. The target scale is 1:1 million, but the project is pragmatic and accepts a range of scales and the best available data. The initiative recognizes that different nations have differing abilities to participate and transfer of know-how to those who need it is a key aspect of the approach. A key contributor to the success of OneGeology has been its utilization of the latest new web technology and an emerging data exchange standard for geological map data called GeoSciML. GeoSciML (GeoScience Markup Language) is a schema written in GML (Geography Markup Language) for geological data. GeoSciML has the ability to represent both the geography (geometries e.g. polygons, lines and points) and geological attribution in a clear and structured format. OneGeology was launched March 2007 at the inaugural workshop in Brighton England. At that workshop the 43 participating nations developed a declaration of a common objective and principles called the “Brighton Accord” (http://onegeology.org/what_is/accord.html) . Work was initiated immediately and the resulting OneGeology Portal was launched at the International Geological Congress in Oslo in August 2008 by Simon Winchester, author of “The Map that Changed the World”. Since the successful launch, OneGeology participants have continued working both to increase national participation and content, and to put in place a more formal governance structure to oversee the long term evolution of the initiative. OneGeology is an example of collaboration in action and is both multilateral and multinational. In 2007, a group of motivated geoscientists and data managers identified an opportunity and took the initiative to engage their peers to work in concert to achieve a shared objective. OneGeology has facilitated collaborative development of an Internet site that provides unprecedented online access to global geological map data.

  1. Hanford Site Guidelines for Preparation and Presentation of Geologic Information

    SciTech Connect

    Lanigan, David C.; Last, George V.; Bjornstad, Bruce N.; Thorne, Paul D.; Webber, William D.

    2010-04-30

    A complex geology lies beneath the Hanford Site of southeastern Washington State. Within this geology is a challenging large-scale environmental cleanup project. Geologic and contaminant transport information generated by several U.S. Department of Energy contractors must be documented in geologic graphics clearly, consistently, and accurately. These graphics must then be disseminated in formats readily acceptable by general graphics and document producing software applications. The guidelines presented in this document are intended to facilitate consistent, defensible, geologic graphics and digital data/graphics sharing among the various Hanford Site agencies and contractors.

  2. Abstracts of the Annual Meeting of Planetary Geologic Mappers, Flagstaff, AZ, 2008

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L. (Editor); Kelley, Michael S. (Editor)

    2008-01-01

    Topics discussed include: Merging of the USGS Atlas of Mercury 1:5,000,000 Geologic Series; Geologic Mapping of the V-36 Thetis Regio Quadrangle: 2008 Progress Report; Structural Maps of the V-17 Beta Regio Quadrangle, Venus; Geologic Mapping of Isabella Quadrangle (V-50) and Helen Planitia, Venus; Renewed Mapping of the Nepthys Mons Quadrangle (V-54), Venus; Mapping the Sedna-Lavinia Region of Venus; Geologic Mapping of the Guinevere Planitia Quadrangle of Venus; Geological Mapping of Fortuna Tessera (V-2): Venus and Earth's Archean Process Comparisons; Geological Mapping of the North Polar Region of Venus (V-1 Snegurochka Planitia): Significant Problems and Comparisons to the Earth's Archean; Venus Quadrangle Geological Mapping: Use of Geoscience Data Visualization Systems in Mapping and Training; Geologic Map of the V-1 Snegurochka Planitia Quadrangle: Progress Report; The Fredegonde (V-57) Quadrangle, Venus: Characterization of the Venus Midlands; Formation and Evolution of Lakshmi Planum (V-7), Venus: Assessment of Models using Observations from Geological Mapping; Geologic Map of the Meskhent Tessera Quadrangle (V-3), Venus: Evidence for Early Formation and Preservation of Regional Topography; Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus: A Progress Report; Geology of the Lachesis Tessera Quadrangle (V-18), Venus; Geologic Mapping of the Juno Chasma Quadrangle, Venus: Establishing the Relation Between Rifting and Volcanism; Geologic Mapping of V-19, V-28, and V-53; Lunar Geologic Mapping Program: 2008 Update; Geologic Mapping of the Marius Quadrangle, the Moon; Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars: Introductory Report; New Geologic Map of the Argyre Region of Mars; Geologic Evolution of the Martian Highlands: MTMs -20002, -20007, -25002, and -25007; Mapping Hesperia Planum, Mars; Geologic Mapping of the Meridiani Region, Mars; Geology of Holden Crater and the Holden and Ladon Multi-Ring Impact Basins, Margaritifer Terra, Mars; Geologic Mapping of Athabasca Valles; Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region of Mars; Geologic Mapping of the Martian Impact Crater Tooting; Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: First Year Results and Second Year Plan; Mars Global Geologic Mapping: Amazonian Results; Recent Geologic Mapping Results for the Polar Regions of Mars; Geologic Mapping of the Medusae Fossae Formation on Mars (MC-8 SE and MC-23 NW) and the Northern Lowlands of Venus (V-16 and V-15); Geologic Mapping of the Zal, Hi'iaka, and Shamshu Regions of Io; Global Geologic Map of Europa; Material Units, Structures/Landforms, and Stratigraphy for the Global Geologic Map of Ganymede (1:15M); and Global Geologic Mapping of Io: Preliminary Results.

  3. Advanced Technologies for Monitoring CO2 Saturation and Pore Pressure in Geologic Formations: Linking the Chemical and Physical Effects to Elastic and Transport Properties

    SciTech Connect

    Mavko, G.; Vanorio, T.; Vialle, S.; Saxena, N.

    2014-03-31

    Ultrasonic P- and S-wave velocities were measured over a range of confining pressures while injecting CO2 and brine into the samples. Pore fluid pressure was also varied and monitored together with porosity during injection. Effective medium models were developed to understand the mechanisms and impact of observed changes and to provide the means for implementation of the interpretation methodologies in the field. Ultrasonic P- and S-wave velocities in carbonate rocks show as much as 20-50% decrease after injection of the reactive CO2-brine mixture; the changes were caused by permanent changes to the rock elastic frame associated with dissolution of mineral. Velocity decreases were observed under both dry and fluid-saturated conditions, and the amount of change was correlated with the initial pore fabrics. Scanning Electron Microscope images of carbonate rock microstructures were taken before and after injection of CO2-rich water. The images reveal enlargement of the pores, dissolution of micrite (micron-scale calcite crystals), and pitting of grain surfaces caused by the fluid- solid chemical reactivity. The magnitude of the changes correlates with the rock microtexture – tight, high surface area samples showed the largest changes in permeability and smallest changes in porosity and elastic stiffness compared to those in rocks with looser texture and larger intergranular pore space. Changes to the pore space also occurred from flow of fine particles with the injected fluid. Carbonates with grain-coating materials, such as residual oil, experienced very little permanent change during injection. In the tight micrite/spar cement component, dissolution is controlled by diffusion: the mass transfer of products and reactants is thus slow and the fluid is expected to be close to thermodynamical equilibrium with the calcite, leading to very little dissolution, or even precipitation. In the microporous rounded micrite and macropores, dissolution is controlled by advection: because of an efficient mass transfer of reactants and products, the fluid remains acidic, far from thermodynamical equilibrium and the dissolution of calcite is important. These conclusions are consistent with the lab observations. Sandstones from the Tuscaloosa formation in Mississippi were also subjected to injection under representative in situ stress and pore pressure conditions. Again, both P- and S-wave velocities decreased with injection. Time-lapse SEM images indicated permanent changes induced in the sandstone microstructure by chamosite dissolution upon injection of CO2-rich brine. After injection, the sandstone showed an overall cleaner microstructure. Two main changes are involved: (a) clay dissolution between grains and at the grain contact and (b) rearrangement of grains due to compaction under pressure Theoretical and empirical models were developed to quantify the elastic changes associated with injection. Permanent changes to the rock frame resulted in seismic velocity-porosity trends that mimic natural diagenetic changes. Hence, when laboratory measurments are not available for a candidate site, these trends can be estimated from depth trends in well logs. New theoretical equations were developed to predict the changes in elastic moduli upon substitution of pore-filling material. These equations reduce to Gassmann’s equations for the case of constant frame properties, low seismic frequencies, and fluid changes in the pore space. The new models also predict the change dissolution or precipitation of mineral, which cannot be described with the conventional Gassmann theory.

  4. Geophysics & Geology Inspected.

    ERIC Educational Resources Information Center

    Neale, E. R. W.

    1981-01-01

    Summarizes findings of a recently published report of the Canadian Geoscience Council, which includes the following topics regarding college geology: facilities; teaching; undergraduate enrollments; postgraduate enrollments; geologic research; and integration of Canadian geoscience with other countries. (CS)

  5. Geology for the Masses

    ERIC Educational Resources Information Center

    Dickinson, William R.

    1970-01-01

    Describes environmental geology as including planning to avoid natural hazards, acquire natural resources, and use land wisely. Describes philosophy and strategies for developing interdisciplinary, environmental geology education at the high school, college, professional graduate, and doctoral research levels. (PR)

  6. Experimental investigation of supercritical CO2 trapping mechanisms at the Intermediate Laboratory Scale in well-defined heterogeneous porous media

    DOE PAGESBeta

    Trevisan, Luca; Pini, Ronny; Cihan, Abdullah; Birkholzer, Jens T.; Zhou, Quanlin; Illangasekare, Tissa H.

    2014-12-31

    The heterogeneous nature of typical sedimentary formations can play a major role in the propagation of the CO2 plume, eventually dampening the accumulation of mobile phase underneath the caprock. From core flooding experiments, it is also known that contrasts in capillary threshold pressure due to different pore size can affect the flow paths of the invading and displaced fluids and consequently influence the build- up of non-wetting phase (NWP) at interfaces between geological facies. The full characterization of the geologic variability at all relevant scales and the ability to make observations on the spatial and temporal distribution of the migrationmore »and trapping of supercritical CO2 is not feasible from a practical perspective. To provide insight into the impact of well-defined heterogeneous systems on the flow dynamics and trapping efficiency of supercritical CO2 under drainage and imbibition conditions, we present an experimental investigation at the meter scale conducted in synthetic sand reservoirs packed in a quasi-two-dimensional flow-cell. Two immiscible displacement experiments have been performed to observe the preferential entrapment of NWP in simple heterogeneous porous media. The experiments consisted of an injection, a fluid redistribution, and a forced imbibition stages conducted in an uncorrelated permeability field and a homogeneous base case scenario. We adopted x-ray attenuation analysis as a non-destructive technique that allows a precise measurement of phase saturations throughout the entire flow domain. By comparing a homogeneous and a heterogeneous scenario we have identified some important effects that can be attributed to capillary barriers, such as dampened plume advancement, higher non-wetting phase saturations, larger contact area between the injected and displaced phases, and a larger range of non-wetting phase saturations.« less

  7. Andrei borisovich vistelius: a dominant figure in 20th century mathematical geology

    USGS Publications Warehouse

    Merriam, D.F.

    2001-01-01

    Andrei Borisovich Vistelius (1915-1995), along with William Christian Krumbein (1902-1979) and John Cedric Griffiths (1912-1992), were dominant figures in the formative and development years of mathematical (or quantitative) geology as a subdiscipline of geology.

  8. Preliminary Geologic Characterization of West Coast States for Geologic Sequestration

    SciTech Connect

    Larry Myer

    2005-09-29

    Characterization of geological sinks for sequestration of CO{sub 2} in California, Nevada, Oregon, and Washington was carried out as part of Phase I of the West Coast Regional Carbon Sequestration Partnership (WESTCARB) project. Results show that there are geologic storage opportunities in the region within each of the following major technology areas: saline formations, oil and gas reservoirs, and coal beds. The work focused on sedimentary basins as the initial most-promising targets for geologic sequestration. Geographical Information System (GIS) layers showing sedimentary basins and oil, gas, and coal fields in those basins were developed. The GIS layers were attributed with information on the subsurface, including sediment thickness, presence and depth of porous and permeable sandstones, and, where available, reservoir properties. California offers outstanding sequestration opportunities because of its large capacity and the potential of value-added benefits from enhanced oil recovery (EOR) and enhanced gas recovery (EGR). The estimate for storage capacity of saline formations in the ten largest basins in California ranges from about 150 to about 500 Gt of CO{sub 2}, depending on assumptions about the fraction of the formations used and the fraction of the pore volume filled with separate-phase CO{sub 2}. Potential CO{sub 2}-EOR storage was estimated to be 3.4 Gt, based on a screening of reservoirs using depth, an API gravity cutoff, and cumulative oil produced. The cumulative production from gas reservoirs (screened by depth) suggests a CO{sub 2} storage capacity of 1.7 Gt. In Oregon and Washington, sedimentary basins along the coast also offer sequestration opportunities. Of particular interest is the Puget Trough Basin, which contains up to 1,130 m (3,700 ft) of unconsolidated sediments overlying up to 3,050 m (10,000 ft) of Tertiary sedimentary rocks. The Puget Trough Basin also contains deep coal formations, which are sequestration targets and may have potential for enhanced coal bed methane recovery (ECBM).

  9. Hydrogeologic inferences from geophysical and geologic investigation of the Standard Mine site, Elk Basin, Colorado

    NASA Astrophysics Data System (ADS)

    Minsley, B. J.; Caine, J. S.; Ball, L. B.; Burton, B.; Curry-Elrod, E.; Manning, A. H.; Verplanck, P. L.

    2009-12-01

    Geophysical and geologic data were collected at the Standard Mine in Elk Basin near Crested Butte, CO, to improve our understanding of the hydrogeologic controls in the basin and how they influence surface and groundwater interactions with nearby mine workings. The Tertiary Ohio Creek and Wasatch formations are the bedrock geologic units; both are primarily sandstones, but with differences in weathering and fracturing. Dikes, near-vertical normal faults, and polymetallic quartz veins with varying degrees of lateral continuity cut the sedimentary units. The net impact of these features, along with basin topography, makes it difficult to predict the behavior of the surface and groundwater systems. This integrated study utilizes geologic observations to help constrain subsurface information obtained from the analysis of surface geophysical measurements. This is a critical step toward using the geophysical data in a meaningful hydrogeologic framework. The approach combines the benefit of direct, but sparse, field observations with spatially continuous, but indirect, measurements of physical properties through the use of geophysics. Surface geophysical data includes electrical resistivity profiles aimed at imaging variability in subsurface structural properties and fluid content; self-potentials, which are sensitive to mineralized zones at this site and, to a lesser extent, shallow flow patterns; and magnetic measurements, which provide information on lateral variability in near-surface geologic features, although the minerals at this site are not strongly magnetized. Downhole caliper and optical televiewer logs were acquired in one well and provide valuable information on fracture properties. Field geologic observations include hand sample mineralogy and detailed mapping and characterization of faults, joints, and veins. Analyses of representative rock samples include magnetic susceptibility, mercury injection capillary pressure, semi-quantitative x-ray diffraction, mass spectroscopy elemental chemistry, and petrography. Preliminary results from all analyses are remarkably consistent with one another and suggest a heterogeneously distributed, fracture-dominated groundwater flow system. Resistivity models show a well-defined, highly resistive near-surface layer, likely representing the unsaturated zone. Selective leaching of pyrite combined with fracturing in the Ohio Creek formation may be responsible for localized areas of lower resistivity where surface waters intersect these features and result in increased saturation. Steeply dipping resistive features are spatially coincident with the observed major faults and veins, and are also evident in the self-potential data. Resistivity data, outcrop observations, petrography, and mercury injection permeability and porosity data are consistent with the Wasatch formation having significantly lower porosity and permeability than the Ohio Creek formation and associated fault rocks. This suggests that the physical juxtaposition of the two contrasting units may be a critical factor in controlling the distribution of surface water infiltration and groundwater-related acid rock drainage.

  10. Factors controlling radionuclide transport behavior in a generic geological radioactive waste repository

    NASA Astrophysics Data System (ADS)

    Bianchi, M.; Liu, H.; Birkholzer, J. T.

    2013-12-01

    One of the main challenges in designing a geological repository for high-level nuclear waste is the assessment of postclosure safety, which involves the long-term ability of the engineered system and the geological host formation to contain and delay the leakage of radionuclides toward the biosphere. A correct assessment requires detailed knowledge of the factors controlling radionuclide transport in the different components of the geological disposal system. For instance, molecular diffusion, which is considered the dominant transport mechanism in low-permeable geological formations, may be influenced by the heterogeneity of the diffusive parameters and by electrochemical processes. Likewise, the prevalence of advective transport in the near-field excavation damaged zone (EDZ) may be controlled by the hydrogeological conditions in the host formation, as well as by hydrogeological and geometrical properties. In this study, we performed two-dimensional numerical simulations of groundwater flow and radionuclide transport to study the influence of several factors on the prevailing transport mechanism (i.e., advection or molecular diffusion) in the different components of a geological nuclear waste repository system. Particular attention was given to the excavation damaged zone (EDZ) around the repository tunnels and access shaft, which was modeled as a single effective continuum as well as with the dual-porosity approach. We considered different hydrogeological and geometrical factors, including the ambient hydraulic gradient, the presence of groundwater pressure anomalies, and the thickness of the EDZ and its hydraulic properties. By comparing simulation results, we show that transport behavior and the role of the EDZ as a preferential flow path for radionuclide transport is most sensitive to the hydrogeological conditions in the host rock. When the hydraulic gradient in the host rock is reduced by a factor of 5 from the unit value, we observe a significant reduction in the area within the EDZ where advection dominates. However, the presence of overpressures in the host rock, as typically observed in clay-rock formations in sedimentary basins, can significantly increase the importance of advection and consequentially transport velocity, even in systems with a low regional hydraulic gradient. The opposite behavior was observed for an undepressurized system. Transport behavior is also sensitive to the modeling approach used to simulate flow in the EDZ fractures, and to geometrical and hydrogeological parameters of the EDZ.

  11. GEOLOGY 619 ADVANCED PETROLEUM GEOLOGY Wayne M. Ahr, Professor, CPG

    E-print Network

    GEOLOGY 619 ­ ADVANCED PETROLEUM GEOLOGY Wayne M. Ahr, Professor, CPG Draft v.1 ­ October, 2008 Advanced Petroleum Geology is designed for graduate students in geology, geophysics, and engineering. This course differs from Geology 404 ­ Petroleum Geology ­ by its more rigorous treatment of subject matter

  12. Endothelial Cell Heterogeneity

    PubMed Central

    Aird, William C.

    2012-01-01

    The endothelial lining of blood vessels shows remarkable heterogeneity in structure and function, in time and space, and in health and disease. An understanding of the molecular basis for phenotypic heterogeneity may provide important insights into vascular bed-specific therapies. First, we review the scope of endothelial heterogeneity and discuss its proximate and evolutionary mechanisms. Second, we apply these principles, together with their therapeutic implications, to a representative vascular bed in disease, namely, tumor endothelium. PMID:22315715

  13. Geological and production characteristics of strandplain/barrier island reservoirs in the United States

    SciTech Connect

    Cole, E.L.; Fowler, M.; Jackson, S.; Madden, M.P.; Reeves, T.K.; Salamy, S.P.; Young, M.A.

    1994-12-01

    The Department of Energy`s (DOE`s) primary mission in the oil research program is to maximize the economically and environmentally sound recovery of oil from domestic reservoirs and to preserve access to this resource. The Oil Recovery Field Demonstration Program supports DOE`s mission through cost-shared demonstrations of improved Oil Recovery (IOR) processes and reservoir characterization methods. In the past 3 years, the DOE has issued Program Opportunity Notices (PONs) seeking cost-shared proposals for the three highest priority, geologically defined reservoir classes. The classes have been prioritized based on resource size and risk of abandonment. This document defines the geologic, reservoir, and production characteristics of the fourth reservoir class, strandplain/barrier islands. Knowledge of the geological factors and processes that control formation and preservation of reservoir deposits, external and internal reservoir heterogeneities, reservoir characterization methodology, and IOR process application can be used to increase production of the remaining oil-in-place (IOR) in Class 4 reservoirs. Knowledge of heterogeneities that inhibit or block fluid flow is particularly critical. Using the TORIS database of 330 of the largest strandplain/barrier island reservoirs and its predictive and economic models, the recovery potential which could result from future application of IOR technologies to Class 4 reservoirs was estimated to be between 1.0 and 4.3 billion barrels, depending on oil price and the level of technology advancement. The analysis indicated that this potential could be realized through (1) infill drilling alone and in combination with polymer flooding and profile modification, (2) chemical flooding (sufactant), and (3) thermal processes. Most of this future potential is in Texas, Oklahoma, and the Rocky Mountain region. Approximately two-thirds of the potentially recoverable resource is at risk of abandonment by the year 2000.

  14. Heterogeneous Catalysis: On Bathroom Mirrors and Boiling Stones

    ERIC Educational Resources Information Center

    Philipse, Albert P.

    2011-01-01

    Though heterogeneous nucleation of liquid droplets on a smooth surface (such as a bathroom mirror) is a classical topic in nucleation theory, it is not well-known that this topic is actually a pedagogical example of heterogeneous catalysis: the one and only effect of the surface is to lower the activation Gibbs energy of droplet formation. In…

  15. Dealing with spatial heterogeneity

    NASA Astrophysics Data System (ADS)

    Marsily, Gh.; Delay, F.; Gonçalvès, J.; Renard, Ph.; Teles, V.; Violette, S.

    2005-03-01

    Heterogeneity can be dealt with by defining homogeneous equivalent properties, known as averaging, or by trying to describe the spatial variability of the rock properties from geologic observations and local measurements. The techniques available for these descriptions are mostly continuous Geostatistical models, or discontinuous facies models such as the Boolean, Indicator or Gaussian-Threshold models and the Markov chain model. These facies models are better suited to treating issues of rock strata connectivity, e.g. buried high permeability channels or low permeability barriers, which greatly affect flow and, above all, transport in aquifers. Genetic models provide new ways to incorporate more geology into the facies description, an approach that has been well developed in the oil industry, but not enough in hydrogeology. The conclusion is that future work should be focused on improving the facies models, comparing them, and designing new in situ testing procedures (including geophysics) that would help identify the facies geometry and properties. A world-wide catalog of aquifer facies geometry and properties, which could combine site genesis and description with methods used to assess the system, would be of great value for practical applications. On peut aborder le problème de l'hétérogénéité en s'efforçant de définir une perméabilité équivalente homogène, par prise de moyenne, ou au contraire en décrivant la variation dans l'espace des propriétés des roches à partir des observations géologiques et des mesures locales. Les techniques disponibles pour une telle description sont soit continues, comme l'approche Géostatistique, soit discontinues, comme les modèles de faciès, Booléens, ou bien par Indicatrices ou Gaussiennes Seuillées, ou enfin Markoviens. Ces modèles de faciès sont mieux capables de prendre en compte la connectivité des strates géologiques, telles que les chenaux enfouis à forte perméabilité, ou au contraire les faciès fins de barrières de perméabilité, qui ont une influence importante sur les écoulement, et, plus encore, sur le transport. Les modè les génétiques récemment apparus ont la capacité de mieux incorporer dans les modèles de faciès les observations géologiques, chose courante dans l'industrie pétrolière, mais insuffisamment développée en hydrogéologie. On conclut que les travaux de recherche ultérieurs devraient s'attacher à développer les modèles de faciès, à les comparer entre eux, et à mettre au point de nouvelles méthodes d'essais in situ, comprenant les méthodes géophysiques, capables de reconnaître la géométrie et les propriétés des faciès. La constitution d'un catalogue mondial de la géométrie et des propriétés des faciès aquifères, ainsi que des méthodes de reconnaissance utilisées pour arriver à la détermination de ces systèmes, serait d'une grande importance pratique pour les applications. La heterogeneidad se puede manejar por medio de la definición de características homogéneas equivalentes, conocidas como promediar o tratando de describir la variabilidad espacial de las características de las rocas a partir de observaciones geológicas y medidas locales. Las técnicas disponibles para estas descripciones son generalmente modelos geoestadísticos continuos o modelos de facies discontinuos como los modelos Boolean, de Indicador o de umbral de Gaussian y el modelo de cadena de Markow. Estos modelos de facies son mas adecuados para tratar la conectvidad de estratos geológicos (por ejemplo canales de alta permeabilidad enterrados o barreras de baja permeabilidad que tienen efectos importantes sobre el flujo y especialmente sobre el transporte en los acuíferos. Los modelos genéticos ofrecen nuevas formas de incorporar más geología en las descripciones de facies, un enfoque que está bien desarollado en la industria petrolera, pero insuficientemente en la hidrogeología. Se concluye que los trabajos futuros deberían estar más enfocados en mejorar los modelos de facies, en establecer comparaciones y en

  16. Stochastic models of solute transport in highly heterogeneous geologic media

    SciTech Connect

    Semenov, V.N.; Korotkin, I.A.; Pruess, K.; Goloviznin, V.M.; Sorokovikova, O.S.

    2009-09-15

    A stochastic model of anomalous diffusion was developed in which transport occurs by random motion of Brownian particles, described by distribution functions of random displacements with heavy (power-law) tails. One variant of an effective algorithm for random function generation with a power-law asymptotic and arbitrary factor of asymmetry is proposed that is based on the Gnedenko-Levy limit theorem and makes it possible to reproduce all known Levy {alpha}-stable fractal processes. A two-dimensional stochastic random walk algorithm has been developed that approximates anomalous diffusion with streamline-dependent and space-dependent parameters. The motivation for introducing such a type of dispersion model is the observed fact that tracers in natural aquifers spread at different super-Fickian rates in different directions. For this and other important cases, stochastic random walk models are the only known way to solve the so-called multiscaling fractional order diffusion equation with space-dependent parameters. Some comparisons of model results and field experiments are presented.

  17. U.S. Geological Survey Geologic Carbon Sequestration Assessment

    NASA Astrophysics Data System (ADS)

    Warwick, P. D.; Blondes, M. S.; Brennan, S.; Corum, M.; Merrill, M. D.

    2012-12-01

    The Energy Independence and Security Act of 2007 authorized the U.S. Geological Survey (USGS) to conduct a national assessment of potential geological storage resources for carbon dioxide (CO2) in consultation with the U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA) and State geological surveys. To conduct the assessment, the USGS developed a probability-based assessment methodology that was extensively reviewed by experts from industry, government and university organizations (Brennan et al., 2010, http://pubs.usgs.gov/of/2010/1127). The methodology is intended to be used at regional to sub-basinal scales and it identifies storage assessment units (SAUs) that are based on two depth categories below the surface (1) 3,000 to 13,000 ft (914 to 3,962 m), and (2) 13,000 ft (3,962 m) and greater. In the first category, the 3,000 ft (914 m) minimum depth of the storage reservoir ensures that CO2 is in a supercritical state to minimize the storage volume. The depth of 13,000 ft (3,962 m) represents maximum depths that are accessible with average injection pressures. The second category represents areas where a reservoir formation has potential storage at depths below 13,000 ft (3,962 m), although they are not accessible with average injection pressures; these are assessed as a separate SAU. SAUs are restricted to formation intervals that contain saline waters (total dissolved solids greater than 10,000 parts per million) to prevent contamination of protected ground water. Carbon dioxide sequestration capacity is estimated for buoyant and residual storage traps within the basins. For buoyant traps, CO2 is held in place in porous formations by top and lateral seals. For residual traps, CO2 is contained in porous formations as individual droplets held within pores by capillary forces. Preliminary geologic models have been developed to estimate CO2 storage capacity in approximately 40 major sedimentary basins within the United States. More than 200 SAUs have been identified within these basins. The results of the assessment are estimates of the technically accessible storage resources based on present-day geological and engineering technology related to CO2 injection into geologic formations; therefore the assessment is not of total in-place resources. Summary geologic descriptions of the evaluated basins and SAUs will be prepared, along with the national assessment results. During the coming year, these results will be released as USGS publications available from http://energy.usgs.gov. In support of these assessment activities, CO2 sequestration related research science is being conducted by members of the project. Results of our research will contribute to current and future CO2 storage assessments conducted by the USGS and other organizations. Research topics include: (a) geochemistry of CO2 interactions with subsurface environments; (b) subsurface petrophysical rock properties in relation to CO2 injection; (c) enhanced oil recovery and the potential for CO2 storage; (d) storage of CO2 in unconventional reservoirs (coal, shale, and basalt); (e) statistical aggregation of assessment results; and (f) potential risks of induced seismicity.

  18. Geological Survey research 1976

    USGS Publications Warehouse

    U.S. Geological Survey

    1976-01-01

    This U.S. Geological Survey activities report includes a summary of recent (1976 fiscal year) scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral resources, Water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

  19. Geological Survey research 1978

    USGS Publications Warehouse

    U.S. Geological Survey

    1978-01-01

    This U.S. Geological Survey activities report includes a summary of 1978 fiscal year scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral and water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

  20. Geology of the reading prong

    SciTech Connect

    Schutz, D.

    1987-03-01

    For over a billion years the geological terrain now called New Jersey has been the site of unusually high uranium concentrations. Although the highest of these concentrations occurs in the Reading Prong, the area is itself only part of a larger geologic province extending to the northeast and southwest. The rocks in the Reading Prong are not uniformly radioactive. High uranium concentrations tend to be associated with magnetite deposits - metamorphic equivalents of iron-rich formations - and with pegmatites - rocks formed by precipitation from mineralizing solutions in the late phases of granite emplacement. Because of the way they were formed, the uranium-bearing magnetite and pegmatite bodies tend to be long and narrow, and the resulting patterns of radon occurrence can be expected to be the same. This may explain why, in some places, adjacent houses have very different radon concentrations.

  1. Wave Propagation in Jointed Geologic Media

    SciTech Connect

    Antoun, T

    2009-12-17

    Predictive modeling capabilities for wave propagation in a jointed geologic media remain a modern day scientific frontier. In part this is due to a lack of comprehensive understanding of the complex physical processes associated with the transient response of geologic material, and in part it is due to numerical challenges that prohibit accurate representation of the heterogeneities that influence the material response. Constitutive models whose properties are determined from laboratory experiments on intact samples have been shown to over-predict the free field environment in large scale field experiments. Current methodologies for deriving in situ properties from laboratory measured properties are based on empirical equations derived for static geomechanical applications involving loads of lower intensity and much longer durations than those encountered in applications of interest involving wave propagation. These methodologies are not validated for dynamic applications, and they do not account for anisotropic behavior stemming from direcitonal effects associated with the orientation of joint sets in realistic geologies. Recent advances in modeling capabilities coupled with modern high performance computing platforms enable physics-based simulations of jointed geologic media with unprecedented details, offering a prospect for significant advances in the state of the art. This report provides a brief overview of these modern computational approaches, discusses their advantages and limitations, and attempts to formulate an integrated framework leading to the development of predictive modeling capabilities for wave propagation in jointed and fractured geologic materials.

  2. Abbreviations used in publications of the United States Geological Survey

    USGS Publications Warehouse

    U.S. Geological Survey

    1953-01-01

    The use of abbreviations in publications of the Geological Survey is determined by several forces working in different directions. Pulling in the direction of greater condensation and the freer use of abbreviations and symbols is the desire to achieve greater economy in publications. Working in the opposite direction is the desire to have the publications used more conveniently by an increasingly heterogeneous public.

  3. Heterogeneous Semantics in Ptolemy

    E-print Network

    Zakhor, Avideh

    Modeling Heterogeneous Semantics in Ptolemy with Modular Actor Interfaces Chris Shaver working analyses and forms of verification that cross the boundaries of heterogeneous composition. #12;Ptolemy II be understood in clear mathematical terms. From "A Modular Formal Semantics for Ptolemy", Tripakis et al

  4. Geologic mapping of Europa

    USGS Publications Warehouse

    Greeley, R.; Figueredo, P.H.; Williams, D.A.; Chuang, F.C.; Klemaszewski, J.E.; Kadel, S.D.; Prockter, L.M.; Pappalardo, R.T.; Head, J. W., III; Collins, G.C.; Spaun, N.A.; Sullivan, R.J.; Moore, Johnnie N.; Senske, D.A.; Tufts, B.R.; Johnson, T.V.; Belton, M.J.S.; Tanaka, K.L.

    2000-01-01

    Galileo data enable the major geological units, structures, and surface features to be identified on Europa. These include five primary units (plains, chaos, band, ridge, and crater materials) and their subunits, along with various tectonic structures such as faults. Plains units are the most widespread. Ridged plains material spans a wide range of geological ages, including the oldest recognizable features on Europa, and appears to represent a style of tectonic resurfacing, rather than cryovolcanism. Smooth plains material typically embays other terrains and units, possibly as a type of fluid emplacement, and is among the youngest material units observed. At global scales, plains are typically mapped as undifferentiated plains material, although in some areas differences can be discerned in the near infrared which might be related to differences in ice grain size. Chaos material is composed of plains and other preexisting materials that have been severely disrupted by inferred internal activity; chaos is characterized by blocks of icy material set in a hummocky matrix. Band material is arrayed in linear, curvilinear, wedge-shaped, or cuspate zones with contrasting albedo and surface textures with respect to the surrounding terrain. Bilateral symmetry observed in some bands and the relationships with the surrounding units suggest that band material forms by the lithosphere fracturing, spreading apart, and infilling with material derived from the subsurface. Ridge material is mapped as a unit on local and some regional maps but shown with symbols at global scales. Ridge material includes single ridges, doublet ridges, and ridge complexes. Ridge materials are considered to represent tectonic processes, possibly accompanied by the extrusion or intrusion of subsurface materials, such as diapirs. The tectonic processes might be related to tidal flexing of the icy lithosphere on diurnal or longer timescales. Crater materials include various interior (smooth central, rough inner, and annular massif) and exterior (continuous ejecta) subunits. Structural features and landforms are shown with conventional symbols. Type localities for the units are identified, along with suggestions for portraying the features on geological maps, including colors and letter abbreviations for material units. Implementing these suggestions by the planetary mapping community would facilitate comparisons of maps for different parts of Europa and contribute to an eventual global synthesis of its complex geology. On the basis of initial mapping results, a stratigraphic sequence is suggested in which ridged plains form the oldest unit on Europa, followed by development of band material and individual ridges. Band materials tend to be somewhat older than ridges, but in many areas the two units formed simultaneously. Similarly, the formation of most chaos follows the development of ridged plains; although chaos is among the youngest materials on Europa, some chaos units might have formed contemporaneously with ridged plains. Smooth plains generally embay all other units and are late-stage in the evolution of the surface. C1 craters are superposed on ridged plains but are crosscut by other materials, including bands and ridges. Most c2 craters postdate all other units, but a few c2 craters are cut by ridge material. C3 craters constitute the youngest recognizable material on Europa. Copyright 2000 by the American Geophysical Union.

  5. Heterogeneity and anisotropy in the lithospheric mantle

    NASA Astrophysics Data System (ADS)

    Tommasi, Andréa; Vauchez, Alain

    2015-10-01

    The lithospheric mantle is intrinsically heterogeneous and anisotropic. These two properties govern the repartition of deformation, controlling intraplate strain localization and development of new plate boundaries. Geophysical and geological observations provide clues on the types, ranges, and characteristic length scales of heterogeneity and anisotropy in the lithospheric mantle. Seismic tomography points to variations in geothermal gradient and hence in rheological behavior at scales of hundreds of km. Seismic anisotropy data substantiate anisotropic physical properties consistent at scales of tens to hundreds of km. Receiver functions imply lateral and vertical heterogeneity at scales < 10 km, which might record gradients in composition or anisotropy. Observations on naturally deformed peridotites establish that compositional heterogeneity and Crystal Preferred Orientations (CPOs) are ubiquitous from the mm to the km scales. These data allow discussing the processes that produce/destroy heterogeneity and anisotropy and constraining the time scales over which they are active. This analysis highlights: (i) the role of deformation and reactive percolation of melts and fluids in producing compositional and structural heterogeneity and the feedbacks between these processes, (ii) the weak mechanical effect of mineralogical variations, and (iii) the low volumes of fine-grained microstructures and difficulty to preserve them. In contrast, olivine CPO and the resulting anisotropy of mechanical and thermal properties are only modified by deformation. Based on this analysis, we propose that strain localization at the plate scale is, at first order, controlled by large-scale variations in thermal structure and in CPO-induced anisotropy. In cold parts of the lithospheric mantle, grain size reduction may contribute to strain localization, but the low volume of fine-grained domains limits this effect.

  6. Overview: Gas hydrate geology and geography

    SciTech Connect

    Malone, R.D.

    1993-01-01

    Several geological factors which are directly responsible for the presence or absence of gas hydrates have been reviewed and are: tectonic position of the region; sedimentary environments; structural deformation; shale diapirism; hydrocarbon generation and migration; thermal regime in the hydrate formation zone (HFZ); pressure conditions; and hydrocarbon gas supply to the HFZ. Work on gas hydrate formation in the geological environment has made significant advances, but there is still much to be learned. Work is continuing in the deeper offshore areas through the Ocean Drilling Program, Government Agencies, and Industry. The pressure/temperature conditions necessary for formation has been identified for various compositions of natural gas through laboratory investigations and conditions for formation are being advanced through drilling in areas where gas hydrates exist.

  7. Overview: Gas hydrate geology and geography

    SciTech Connect

    Malone, R.D.

    1993-06-01

    Several geological factors which are directly responsible for the presence or absence of gas hydrates have been reviewed and are: tectonic position of the region; sedimentary environments; structural deformation; shale diapirism; hydrocarbon generation and migration; thermal regime in the hydrate formation zone (HFZ); pressure conditions; and hydrocarbon gas supply to the HFZ. Work on gas hydrate formation in the geological environment has made significant advances, but there is still much to be learned. Work is continuing in the deeper offshore areas through the Ocean Drilling Program, Government Agencies, and Industry. The pressure/temperature conditions necessary for formation has been identified for various compositions of natural gas through laboratory investigations and conditions for formation are being advanced through drilling in areas where gas hydrates exist.

  8. SUBSURFACE PROPERTY RIGHTS: IMPLICATIONS FOR GEOLOGIC CO2 SEQUESTRATION

    EPA Science Inventory

    The chapter discusses subsurface property rights as they apply to geologic sequestration (GS) of carbon dioxide (CO2). GS projects inject captured CO2 into deep (greater than ~1 km) geologic formations for the explicit purpose of avoiding atmospheric emission of CO2. Because of t...

  9. SUBSURFACE PROPERTY RIGHTS: IMPLICATIONS FOR GEOLOGIC CO2 SEQUESTRATION (PRESENTATION)

    EPA Science Inventory

    The paper discusses subsurface property rights as they apply to geologic sequestration (GS) of carbon dioxide (CO2). GS projects inject captured CO2 into deep (greater than ~1 km) geologic formations for the explicit purpose of avoiding atmospheric emission of CO2. Because of the...

  10. SUBSURFACE PROPERTY RIGHTS: IMPLICATIONS FOR GEOLOGIC CO2 STORAGE

    EPA Science Inventory

    The paper discusses subsurface property rights as they apply to geologic sequestration (GS) of carbon dioxide (CO2). GS projects inject captured CO2 into deep (greater than ~1 km) geologic formations for the explicit purpose of avoiding atmospheric emission of CO2. Because of the...

  11. Geologic map of the Patagonia Mountains, Santa Cruz County, Arizona

    USGS Publications Warehouse

    Graybeal, Frederick T.; Moyer, Lorre A.; Vikre, Peter; Dunlap, Pamela; Wallis, John C.

    2015-01-01

    Several spatial databases provide data for the geologic map of the Patagonia Mountains in Arizona. The data can be viewed and queried in ArcGIS 10, a geographic information system; a geologic map is also available in PDF format. All products are available online only.

  12. Petroleum geology of Kuwait

    SciTech Connect

    Youash, Y.

    1988-01-01

    The extremely large oil reserves in Kuwait result from the presence of all conditions necessary for hydrocarbon generation, migration, entrapment, and preservation, which can be ascribed to an exceptionally large trap volume in a simple geological setting and a late expulsion and migration from a huge area of thermally mature source rocks. The Lower and middle Cretaceous sequence of Kuwait is among the world's richest hydrocarbon habitats. The depositional history is dominated by sedimentation on a very stable broad platform characterized by quiescence as reflected by a continuous deposition in a slowly subsiding sea bottom. The reservoirs are composed of thick sandstone of the Wara, Burgan, and Zubar formations. In addition to these, Mauddud Limestone forms a good reservoir in the northern fields and, in the south, the oolitic limestone of the Lower Cretaceous in Greater Burgan, Umm Gudair, and Minagish fields contains substantial hydrocarbon deposits. The sandstone reservoirs are the world's largest over 1,500 ft (450 m) in thickness of perfect reservoir quality and composed of well-sorted, medium to coarse-grained sands that were deposited in a littoral or on the edge of a deltaic and coastal environment. The source rocks are mostly likely the same reservoir rocks, particularly with downdip more shaly development of widespread thermally mature organic rich facies juxataposed with a carbonate-sandstone shelf.

  13. Numerical Simulation of Seismic Wave Propagation in the Presence of Complex Near-Surface Heterogeneity Including Surface Topography 

    E-print Network

    Son, Jungrak

    2015-07-20

    representative examples of geological features as near-surface heterogeneities are analyzed in seismic modeling with synthetic earth models. The structures are a shallow small scatterer, a collapsed karst structure and a low-velocity top layer with surface...

  14. Final Technical Report - Investigation into the Relationship between Heterogeneity and Heavy-Tailed Solute Transport

    SciTech Connect

    Weissmann, Gary S

    2013-12-06

    The objective of this project was to characterize the influence that naturally complex geologic media has on anomalous dispersion and to determine if the nature of dispersion can be estimated from the underlying heterogeneous media. The UNM portion of this project was to provide detailed representations of aquifer heterogeneity through producing highly-resolved models of outcrop analogs to aquifer materials. This project combined outcrop-scale heterogeneity characterization (conducted at the University of New Mexico), laboratory experiments (conducted at Sandia National Laboratory), and numerical simulations (conducted at Sandia National Laboratory and Colorado School of Mines). The study was designed to test whether established dispersion theory accurately predicts the behavior of solute transport through heterogeneous media and to investigate the relationship between heterogeneity and the parameters that populate these models. The dispersion theory tested by this work was based upon the fractional advection-dispersion equation (fADE) model. Unlike most dispersion studies that develop a solute transport model by fitting the solute transport breakthrough curve, this project explored the nature of the heterogeneous media to better understand the connection between the model parameters and the aquifer heterogeneity. We also evaluated methods for simulating the heterogeneity to see whether these approaches (e.g., geostatistical) could reasonably replicate realistic heterogeneity. The UNM portion of this study focused on capturing realistic geologic heterogeneity of aquifer analogs using advanced outcrop mapping methods.

  15. Geology Before Pluto: Pre-encounter Considerations

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey M.

    2014-01-01

    Pluto, its large satellite Charon, and its four known satellites represent the first trans-Neptunian Kuiper Belt objects populating the outer-most solar system beyond the gas giant planets to be studied in detail from a spacecraft (New Horizons). A complete picture of the solar nebula, and solar system formation cannot be confidently formulated until representatives of this group of bodies at the edge of solar space have been examined. The Pluto system is composed of unique lunar- and intermediate-sized objects that can tell us much about how objects with volatile icy compositions evolve. Modeling of the interior suggests that geologic activity may have been to some degree, and observations of frost on the surface could imply the need for a geologic reservoir for the replenishment of these phases. However, the putative indicators of Pluto's geologic history are inconclusive and unspecific. Detailed examination of Pluto's geologic record is the only plausible means of bridging the gap between theory and observations. In this talk I will examine the potential importance of these tentative indications of geologic activity and how specific spacecraft observations have been designed and used to constrain the Pluto system's geologic history. The cameras of New Horizons will provide robust data sets that should be immanently amenable to geological analysis of the Pluto System's landscapes. In this talk, we begin with a brief discussion of the planned observations by New Horizons' cameras that will bear most directly on geological interpretability. Then I will broadly review major geological processes that could potentially operate of the surfaces of Pluto and its moons. I will first survey exogenic processes (i.e., those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration) and the work of wind. I will conclude with an assessment of prospects for endogenic activity in the form of tectonics and cryo-volcanism.

  16. Geology Before Pluto: Pre-encounter Considerations

    NASA Astrophysics Data System (ADS)

    Moore, J. M.

    2014-12-01

    Pluto, its large satellite Charon, and its four small known satellites represent the first trans-Neptunian Kuiper Belt objects populating the outer-most solar system beyond the gas giant planets to be studied in detail from a spacecraft (New Horizons). A complete picture of the solar nebula and solar system formation cannot be confidently formulated until representatives of this group of bodies at the edge of solar space have been examined. The Pluto system is composed of unique, lunar- and intermediate-sized objects that can tell us much about how objects with volatile icy compositions evolve. Modeling of the interior suggests that geologic activity may have been significant to some degree, and observations of frost on the surface could imply the need for a geologic reservoir for the replenishment of these phases. However, these putative indicators of Pluto's geologic history are inconclusive and unspecific. Detailed examination of Pluto's geologic record is the only plausible means of bridging the gap between theory and observation. In this talk I will examine the potential importance of these tentative indications of geologic activity and how specific spacecraft observations have been designed and used to constrain the Pluto system's geologic history. The cameras of New Horizons will provide robust data sets that should be immanently amenable to geological analysis of the Pluto system's landscapes. In this talk, we begin with a brief discussion of the planned observations by the New Horizons cameras that will bear most directly on geological interpretability. Then I will broadly review major geological processes that could potentially operate on the surfaces of Pluto and its moons. I will first survey exogenic processes (i.e., those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration), and the work of wind. I will conclude with an assessment of the prospects for endogenic activity in the form of tectonics and cryovolcanism.

  17. Heterogeneous Oxidation of Catechol.

    PubMed

    Pillar, Elizabeth A; Zhou, Ruixin; Guzman, Marcelo I

    2015-10-15

    Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air-solid interface under variable relative humidity (RH = 0-90%). The maximum reactive uptake coefficient of O3(g) by catechol ?O3 = (7.49 ± 0.35) × 10(-6) occurs for 90% RH. Upon exposure of ca. 104-?m thick catechol films to O3(g) mixing ratios between 230 ppbv and 25 ppmv, three main reaction pathways are observed. (1) The cleavage of the 1,2 carbon-carbon bond at the air-solid interface resulting in the formation of cis,cis-muconic acid via primary ozonide and hydroperoxide intermediates. Further direct ozonolysis of cis,cis-muconic yields glyoxylic, oxalic, crotonic, and maleic acids. (2) A second pathway is evidenced by the presence of Baeyer-Villiger oxidation products including glutaconic 4-hydroxy-2-butenoic and 5-oxo-2-pentenoic acids during electrospray ionization mass spectrometry (MS) and ion chromatography MS analyses. (3) Finally, indirect oxidation by in situ produced hydroxyl radical (HO(•)) results in the generation of semiquinone radical intermediates toward the synthesis of polyhydoxylated aromatic rings such as tri-, tetra-, and penta-hydroxybenzene. Remarkably, heavier polyhydroxylated biphenyl and terphenyl products present in the extracted oxidized films result from coupling reactions of semiquinones of catechol and its polyhydroxylated rings. The direct ozonolysis of 1,2,3- and 1,2,4-trihydroxybenezene yields 2- and 3-hydroxy-cis,cis-muconic acid, respectively. The production of 2,4- or 3,4-dihdroxyhex-2-enedioic acid is proposed to result from the sequential processing of cis,cis-muconic acid, 2- and 3-hydroxy-cis,cis-muconic acid. Overall, these reactions contribute precursors to form aqueous SOA from aromatics in atmospheric aerosols and brown clouds. PMID:26403273

  18. Life on Guam: Geology. 1977 Edition.

    ERIC Educational Resources Information Center

    Elkins, Gail; And Others

    As part of an updated series of activity oriented educational materials dealing with aspects of the Guam environment, this publication focuses on the physical environment of Guam through an introduction to the geology of Guam. Contents include the formation of Guam, weathering and erosion, earthquakes, soil, and water. Activities investigate…

  19. Geological myths and reality

    NASA Astrophysics Data System (ADS)

    Ostrihansky, Lubor

    2014-05-01

    Myths are the result of man's attempts to explain noteworthy features of his environment stemming from unfounded imagination. It is unbelievable that in 21st century the explanation of evident lithospheric plates movements and origin of forces causing this movement is still bound to myths, They are the myth about mantle convection, myth about Earth's expansion, myth about mantle heterogeneities causing the movement of plates and myth about mantle plumes. From 1971 to 1978 I performed extensive study (Ost?ihanský 1980) about the terrestrial heat flow and radioactive heat production of batholiths in the Bohemian Massive (Czech Republic). The result, gained by extrapolation of the heat flow and heat production relationship, revealed the very low heat flow from the mantle 17.7mW m-2 close to the site of the Quarterly volcano active only 115,000 - 15,000 years ago and its last outbreak happened during Holocene that is less than 10,000 years ago. This volcano Komorní H?rka (Kammerbühls) was known by J. W. Goethe investigation and the digging of 300 m long gallery in the first half of XIX century to reach the basaltic plug and to confirm the Stromboli type volcano. In this way the 19th century myth of neptunists that basalt was a sedimentary deposit was disproved in spite that famous poet and scientist J.W.Goethe inclined to neptunists. For me the result of very low heat flow and the vicinity of almost recent volcanoes in the Bohemian Massive meant that I refused the hypothesis of mantle convection and I focused my investigation to external forces of tides and solar heat, which evoke volcanic effects, earthquakes and the plate movement. To disclose reality it is necessary to present calculation of acting forces using correct mechanism of their action taking into account tectonic characteristics of geologic unites as the wrench tectonics and the tectonic of planets and satellites of the solar system, realizing an exceptional behavior of the Earth as quickly rotating body exposed to strong tidal action of Moon and Sun. Ostrihansky, L.: The structure of the earth's crust and the heat-flow--heat-generation relationship in the Bohemian Massif. Tectonophysics, 68(3-4), 325-337, doi:10.1016/0040-1951(80)90182-1 1980.

  20. 12.001 Introduction to Geology, Spring 2011

    E-print Network

    Perron, Taylor

    This course introduces students to the basics of geology. Through a combination of lectures, labs, and field observations, we will address topics ranging from formation of the elements, mineral and rock identification, and ...

  1. Geological Survey research 1981

    USGS Publications Warehouse

    U.S. Geological Survey

    1982-01-01

    This U.S. Geological Survey activities report includes a summary of 1981 fiscal year scientific and economic results accompanied by a list of geologic, hydrologic, and cartographic investigations in progress. The summary of results includes: (1) Mineral, (2) Water resources, (3) Engineering geology and hydrology, (4) Regional geology, (5) Principles and processes, (6) Laboratory and field methods, (7) Topographic surveys and mapping, (8) Management of resources on public lands, (9) Land information and analysis, and (10) Investigations in other countries. Also included are lists of investigations in progress. (USGS)

  2. Stability of Heterogeneous Ecosystem

    NASA Astrophysics Data System (ADS)

    Liu, Yang-Yu; Yan, Gang; Barabasi, Alber-Laszlo

    2014-03-01

    Stability of ecosystem measures the tendency of a community to return to equilibrium after environmental perturbation, which is severely constrained by the underlying network structure. Despite significant advances in uncovering the relationship between stability and network structure, little attention has been paid to the impact of the degree heterogeneity that exists in real ecosystems. Here we show that for networks with mixed interactions of competition and mutualism the degree heterogeneity always destabilizes the ecosystem. Surprisingly, for predator-prey interactions (e.g., food webs) high heterogeneity is destabilizing yet moderate heterogeneity is stabilizing. These findings deepen our understanding of the stability of real ecosystems and may also have implications in studying the stability of more general complex dynamical systems.

  3. Towards heterogeneous distributed debugging

    SciTech Connect

    Damodaran-Kamal, S.K.

    1995-04-01

    Several years of research and development in parallel debugger design have given up several techniques, though implemented in a wide range of tools for an equally wide range of systems. This paper is an evaluation of these myriad techniques as applied to the design of a heterogeneous distributed debugger. The evaluation is based on what features users perceive as useful, as well as the ease of implementation of the features using the available technology. A preliminary architecture for such a heterogeneous tool is proposed. Our effort in this paper is significantly different from the other efforts at creating portable and heterogeneous distributed debuggers in that we concentrate on support for all the important issues in parallel debugging, instead of simply concentrating on portability and heterogeneity.

  4. Development Plus Kinetic and Mechanistic Studies of a Prototype Supported-Nanoparticle Heterogeneous Catalyst Formation System in Contact with Solution: Ir(1,5-COD)Cl/ -Al2O3 and Its Reduction by H2 to Ir(0)n/?-Al2O3

    SciTech Connect

    Mondloch, J.; Wang, Q; Frenkel, A; Finke, R

    2010-01-01

    An important question and hence goal in catalysis is how best to transfer the synthetic and mechanistic insights gained from the modern revolution in nanoparticle synthesis, characterization, and catalysis to prepare the next generation of improved, supported-nanoparticle heterogeneous catalysts. It is precisely this question and to-date somewhat elusive goal which are addressed by the present work. More specifically, the global hypothesis investigated herein is that the use of speciation-controlled, well-characterized, solid oxide supported-organometallic precatalysts in contact with solution will lead to the next generation of better composition, size- and shape-controlled, as well as highly active and reproducible, supported-nanoparticle heterogeneous catalysts-ones that can also be understood kinetically and mechanistically. Developed herein are eight criteria defining a prototype system for supported-nanoparticle heterogeneous catalyst formation in contact with solution. The initial prototype system explored is the precatalyst, Ir(1,5-COD)Cl/{gamma}-Al{sub 2}O{sub 3} (characterized via ICP, CO adsorption, IR, and XAFS spectroscopies), and the well-defined product, Ir(0){sub n}/{gamma}-Al{sub 2}O{sub 3} (characterized by reaction stoichiometry, TEM, and XAFS). The Ir(0){sub n}/{gamma}-Al{sub 2}O{sub 3} system proved to be a highly active and long-lived catalyst in the simple test reaction of cyclohexene hydrogenation and in comparison to two literature Ir(0){sub n}/Al{sub 2}O{sub 3} heterogeneous catalysts examined under identical conditions. High activity (2.2-4.8-fold higher than that of the literature Ir(0){sub n}/Al{sub 2}O{sub 3} catalysts tested under the same conditions) and good lifetime ({ge} 220,000 total turnovers of cyclohexene hydrogenation) are observed, in part by design since only acetone solvent, cyclohexene, and H{sub 2} are possible ligands in the resultant 'weakly ligated/labile-ligand' supported nanoclusters. Significantly, the Ir(1,5-COD)Cl/{gamma}-Al{sub 2}O{sub 3} + H{sub 2} {yields} Ir(0){sub n}/{gamma}-Al{sub 2}O{sub 3} heterogeneous catalyst formation kinetics were also successfully monitored using the cyclohexene hydrogenation reporter reaction method previously developed and applied to solution-nanoparticle formation. The observed sigmoidal supported-nanoparticle heterogeneous catalyst formation kinetics, starting from the Ir(1,5-COD)Cl/{gamma}-Al{sub 2}O{sub 3} precatalyst, are closely fit by the two-step mechanism of slow continuous nucleation (A {yields} B, rate constant k{sub 1} = 1.5(1.1) x 10{sup -3} h{sup -1}) followed by fast autocatalytic surface growth (A + B {yields} 2B, rate constant k{sub 2} = 1.6(2) x 10{sup 4} h{sup -1} M{sup -1}), where A is the Ir(1,5-COD)Cl/{gamma}-Al{sub 2}O{sub 3} precatalyst and B is the resultant Ir(0){sub n}/{gamma}-Al{sub 2}O{sub 3} catalyst. The kinetics are significant in establishing the ability to monitor the formation of supported-nanoparticle heterogeneous catalysts in contact with solution. They also suggest that the nine synthetic and mechanistic insights from the two-step mechanism of nanoparticle formation in solution should now apply also to the formation of supported-nanoparticle heterogeneous catalysts in contact with solution. The results open the door for new syntheses of supported-nanoparticle heterogeneous catalysts under nontraditional, mild, and flexible conditions where supported organometallics and other precursors are in contact with solution, so that additional variables such as the solvent choice, added ligands, solution temperature, and so on can be used to control the catalyst formation steps and, ideally, the resultant supported-nanoparticle heterogeneous catalyst composition, size, and shape.

  5. A data base of geologic field spectra

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.; Goetz, A. F. H.; Paley, H. N.; Alley, R. E.; Abbott, E. A.

    1981-01-01

    It is noted that field samples measured in the laboratory do not always present an accurate picture of the ground surface sensed by airborne or spaceborne instruments because of the heterogeneous nature of most surfaces and because samples are disturbed and surface characteristics changed by collection and handling. The development of new remote sensing instruments relies on the analysis of surface materials in their natural state. The existence of thousands of Portable Field Reflectance Spectrometer (PFRS) spectra has necessitated a single, all-inclusive data base that permits greatly simplified searching and sorting procedures and facilitates further statistical analyses. The data base developed at JPL for cataloging geologic field spectra is discussed.

  6. Heterogeneity induces emergent functional networks for synchronization

    NASA Astrophysics Data System (ADS)

    Scafuti, Francesco; Aoki, Takaaki; di Bernardo, Mario

    2015-06-01

    We study the evolution of heterogeneous networks of oscillators subject to a state-dependent interconnection rule. We find that heterogeneity in the node dynamics is key in organizing the architecture of the functional emerging networks. We demonstrate that increasing heterogeneity among the nodes in state-dependent networks of phase oscillators causes a differentiation in the activation probabilities of the links when a distributed local network adaptation strategy is used in an evolutionary manner. This, in turn, yields the formation of hubs associated to nodes with larger distances from the average frequency of the ensemble. Our generic local evolutionary strategy can be used to solve a wide range of synchronization and control problems.

  7. Abstracts of the Annual Meeting of Planetary Geologic Mappers, San Antonio, TX, 2009

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L.; Kelley, Michael S.

    2009-01-01

    Topics covered include: Geologic Mapping of the Beta-Atla-Themis (BAT) Region of Venus: A Progress Report; Geologic Map of the Snegurochka Planitia Quadrangle (V-1): Implications for Tectonic and Volcanic History of the North Polar Region of Venus; Preliminary Geological Map of the Fortuna Tessera (V-2) Quadrangle, Venus; Geological Map of the Fredegonde (V-57) Quadrangle, Venus; Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus; Geologic Mapping of V-19; Lunar Geologic Mapping: A Preliminary Map of a Portion of the LQ-10 ("Marius") Quadrangle; Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schr dinger Basin; Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars; Geologic Mapping Investigations of the Northwest Rim of Hellas Basin, Mars; Geologic Mapping of the Meridiani Region of Mars; Geology of a Portion of the Martian Highlands: MTMs -20002, -20007, -25002 and -25007; Geologic Mapping of Holden Crater and the Uzboi-Ladon-Morava Outflow System; Mapping Tyrrhena Patera and Hesperia Planum, Mars; Geologic Mapping of Athabaca Valles; Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region, Mars Topography of the Martian Impact Crater Tooting; Mars Structural and Stratigraphic Mapping along the Coprates Rise; Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan; Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: Second Year Results and Third Year Plan; Mars Global Geologic Mapping: About Half Way Done; New Geologic Map of the Scandia Region of Mars; Geologic Mapping of the Medusae Fossae Formation on Mars and the Northern Lowland Plains of Venus; Volcanism on Io: Insights from Global Geologic Mapping; and Planetary Geologic Mapping Handbook - 2009.

  8. Structural geology of the Earth's exterior*

    PubMed Central

    Burchfiel, B. C.

    1979-01-01

    Plate tectonics offers an explanation for the present motions and heterogeneity of the rocks that form the external part of the Earth. It explains the origin of the first-order heterogeneity of oceanic and continental lithospheres. Furthermore, it explains the youth and simplicity of the oceanic lithosphere and offers the potential to explain the antiquity, complexity, and evolution of the continental lithosphere. The framework of plate tectonics must be used carefully, because there are geological features within continents, particularly in the more ancient rocks, that may require alternative explanations. The task of understanding lithospheric motions through geologic time must be focused on the continents, where the major evidence for 95% of Earth history resides. In interpreting earth motions from the geologic record, three needs seem paramount: (i) to develop a three-dimensional understanding of the kinematics, dynamics, and thermal structure of modern plate boundary systems and at the same time to recognize those geological and geophysical features that are unrelated to plate interaction; (ii) to use this understanding to reconstruct the extent and evolution of ancient systems that form the major elements of continental crust; and (iii) to determine the dynamics and evolution of systems that have no modern analogs. Decoupling along subhorizontal zones within the lithosphere may be widespread in all types of plate boundary systems. Thus, in order to interpret the motion and dynamics of the mantle correctly, it is important to know if upper lithospheric motion within boundary systems is controlled directly or indirectly by or is independent of deeper mantle motions. PMID:16592704

  9. Structural geology of the Earth's exterior.

    PubMed

    Burchfiel, B C

    1979-09-01

    Plate tectonics offers an explanation for the present motions and heterogeneity of the rocks that form the external part of the Earth. It explains the origin of the first-order heterogeneity of oceanic and continental lithospheres. Furthermore, it explains the youth and simplicity of the oceanic lithosphere and offers the potential to explain the antiquity, complexity, and evolution of the continental lithosphere. The framework of plate tectonics must be used carefully, because there are geological features within continents, particularly in the more ancient rocks, that may require alternative explanations. The task of understanding lithospheric motions through geologic time must be focused on the continents, where the major evidence for 95% of Earth history resides.IN INTERPRETING EARTH MOTIONS FROM THE GEOLOGIC RECORD, THREE NEEDS SEEM PARAMOUNT: (i) to develop a three-dimensional understanding of the kinematics, dynamics, and thermal structure of modern plate boundary systems and at the same time to recognize those geological and geophysical features that are unrelated to plate interaction; (ii) to use this understanding to reconstruct the extent and evolution of ancient systems that form the major elements of continental crust; and (iii) to determine the dynamics and evolution of systems that have no modern analogs. Decoupling along subhorizontal zones within the lithosphere may be widespread in all types of plate boundary systems. Thus, in order to interpret the motion and dynamics of the mantle correctly, it is important to know if upper lithospheric motion within boundary systems is controlled directly or indirectly by or is independent of deeper mantle motions. PMID:16592704

  10. Glossary of geology

    SciTech Connect

    Bates, R.L.; Jackson, J.A.

    1987-01-01

    This third edition of the Glossary of Geology contains approximately 37,000 terms, or 1,000 more than the second edition. New entries are especially numerous in the fields of carbonate sedimentology, hydrogeology, marine geology, mineralogy, ore deposits, plate tectonics, snow and ice, and stratigraphic nomenclature. Many of the definitions provide background information.

  11. Geologic time scale bookmark

    USGS Publications Warehouse

    U.S. Geological Survey

    2012-01-01

    This bookmark, designed for use with U.S. Geological Survey activities at the 2nd USA Science and Engineering Festival (April 26–29, 2012), is adapted from the more detailed Fact Sheet 2010–3059 "Divisions of Geologic Time." The information that it presents is widely sought by educators and students.

  12. Advances in planetary geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (editor)

    1981-01-01

    This second issue in a new series intended to serve the planetary geology community with a form for quick and thorough communications includes (1) a catalog of terrestrial craterform structures for northern Europe; (2) abstracts of results of the Planetary Geology Program, and (3) a list of the photographic holdings of regional planetary image facilities.

  13. Geology of the Caribbean.

    ERIC Educational Resources Information Center

    Dillon, William P.; And Others

    1988-01-01

    Describes some of the geologic characteristics of the Caribbean region. Discusses the use of some new techniques, including broad-range swath imaging of the sea floor that produces photograph-like images, and satellite measurement of crustal movements, which may help to explain the complex geology of the region. (TW)

  14. People and Geology.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on the many natural resources we extract from the earth's crust, including metals, graphite, and other minerals, as well as fossil fuels. Contains teaching activities such as a geologic scavenger hunt, a geology chronology, and the recycling of aluminum. Includes a reproducible handout for the activity on aluminum.…

  15. Radiometric Dating in Geology.

    ERIC Educational Resources Information Center

    Pankhurst, R. J.

    1980-01-01

    Described are several aspects and methods of quantitatively measuring geologic time using a constant-rate natural process of radioactive decay. Topics include half lives and decay constants, radiogenic growth, potassium-argon dating, rubidium-strontium dating, and the role of geochronology in support of geological exploration. (DS)

  16. Report on geologic exploration activities

    SciTech Connect

    Breslin, J.; Laughon, R. B.; Hall, R. J.; Voss, J. W.

    1980-01-01

    This report provides an overview of the geological exploration activities being carried out as part of the National Waste Terminal Storage (NWTS) Program, which has been established by the US Department of Energy (DOE) to develop the technology and provide the facilities for the safe, environmentally acceptable isolation of civilian high-level and transuranic nuclear wastes, including spent fuel elements, for which the Federal government is responsible. The principal programmatic emphasis is on disposal in mined geologic repositories. Explorations are being conducted or planned in various parts of the country to identify potential sites for such repositories. The work is being undertaken by three separate but coordinated NWTS project elements. Under the Basalt Waste Isolation Project (BWIP), basalt formations underlying DOE's Hanford Reservation are being investigated. Granite, tuff, and shale formations at the DOE Nevada Test Site (NTS) are being similarly studied in the Nevada Nuclear Waste Storage Investigations (NNWSI). The Office of Nuclear Waste Isolation (ONWI) is investigating domed salt formations in several Gulf Coast states and bedded salt formations in Utah and Texas. The ONWI siting studies are being expanded to include areas overlying crystalline rocks, shales, and other geohydrologic systems. The current status of these NWTS efforts, including the projected budgets for FY 1981, is summarized, and the criteria and methodology being employed in the explorations are described. The consistency of the overall effort with the recommendations presented in the Report to the President by the Interagency Review Group on Nuclear Waste Management (IRG), as well as with documents representing the national technical consensus, is discussed.

  17. doi:10.1130/G25699A.1 2009;37;615-618Geology

    E-print Network

    Benning, Liane G.

    terrestrial biosphere depends. Rock weathering through disso- lution reactions also affects the chemical weathering: Early stages of mineral alteration at the Geology on 29 June 2009geology;GEOLOGY, July 2009 615 ABSTRACT Plant-driven fungal weathering is a major pathway of soil formation, yet

  18. Field Geology/Processes

    NASA Technical Reports Server (NTRS)

    Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

    1996-01-01

    The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

  19. A conceptual sedimentological-geostatistical model of aquifer heterogeneity based on outcrop studies

    SciTech Connect

    Davis, J.M.

    1994-01-01

    Three outcrop studies were conducted in deposits of different depositional environments. At each site, permeability measurements were obtained with an air-minipermeameter developed as part of this study. In addition, the geological units were mapped with either surveying, photographs, or both. Geostatistical analysis of the permeability data was performed to estimate the characteristics of the probability distribution function and the spatial correlation structure. The information obtained from the geological mapping was then compared with the results of the geostatistical analysis for any relationships that may exist. The main field site was located in the Albuquerque Basin of central New Mexico at an outcrop of the Pliocene-Pleistocene Sierra Ladrones Formation. The second study was conducted on the walls of waste pits in alluvial fan deposits at the Nevada Test Site. The third study was conducted on an outcrop of an eolian deposit (miocene) south of Socorro, New Mexico. The results of the three studies were then used to construct a conceptual model relating depositional environment to geostatistical models of heterogeneity. The model presented is largely qualitative but provides a basis for further hypothesis formulation and testing.

  20. Geol 102 Historical Geology The Geologic Timescale 2015

    E-print Network

    Holtz Jr., Thomas R.

    Geol 102 Historical Geology The Geologic Timescale 2015 EON ERA PERIOD (Special Units) EPOCH Range Proterozoic Mesoproterozoic Paleoproterozoic Carboniferous Phanerozoic CenozoicMesozoicPaleozoic Quaternary

  1. Diffusion limited soil vapor extraction: Geologic and bed thickness controls

    SciTech Connect

    Beckett, G.D. ); Benson, D.A. )

    1996-01-01

    Soil vapor extraction (SVE) can remove volatile contaminants from the subsurface environment. In a heterogeneous geologic setting, SVE cleanup will progress rapidly through advective mass transfer in permeable sediments and primarily through slow diffusion in lower permeability soil. The contrast in rates of cleanup between high and low permeability soils is further increased by the associated soil moisture retention contrasts (i.e., capillarity) in the same soils. Low permeability soil generally has a higher soil suction capacity and moisture content than high permeability soil. This results in further diminishment of cleanup rate in fine-grained sediments in a heterogeneous environment. This paper investigates how contrasts in soil type and bed thickness affect the rate of SVE diffusive cleanup. The numerical model VENT3D is used to simulate three heterogeneous geologic settings with differing soil contrasts. Within each geologic setting, four simulations are performed with varying bed thicknesses in each, effectively changing the diffusive half-length of the fine-grained soils while maintaining the total bulk percentages of fine-to coarse-grained material. Under these conditions, the bulk flow parameters measured during SVE field testing would be constant for each of the four simulations within a single geologic domain while the cleanup times would not.

  2. Diffusion limited soil vapor extraction: Geologic and bed thickness controls

    SciTech Connect

    Beckett, G.D.; Benson, D.A.

    1996-12-31

    Soil vapor extraction (SVE) can remove volatile contaminants from the subsurface environment. In a heterogeneous geologic setting, SVE cleanup will progress rapidly through advective mass transfer in permeable sediments and primarily through slow diffusion in lower permeability soil. The contrast in rates of cleanup between high and low permeability soils is further increased by the associated soil moisture retention contrasts (i.e., capillarity) in the same soils. Low permeability soil generally has a higher soil suction capacity and moisture content than high permeability soil. This results in further diminishment of cleanup rate in fine-grained sediments in a heterogeneous environment. This paper investigates how contrasts in soil type and bed thickness affect the rate of SVE diffusive cleanup. The numerical model VENT3D is used to simulate three heterogeneous geologic settings with differing soil contrasts. Within each geologic setting, four simulations are performed with varying bed thicknesses in each, effectively changing the diffusive half-length of the fine-grained soils while maintaining the total bulk percentages of fine-to coarse-grained material. Under these conditions, the bulk flow parameters measured during SVE field testing would be constant for each of the four simulations within a single geologic domain while the cleanup times would not.

  3. A quantitative measure for protein conformational heterogeneity

    NASA Astrophysics Data System (ADS)

    Lyle, Nicholas; Das, Rahul K.; Pappu, Rohit V.

    2013-09-01

    Conformational heterogeneity is a defining characteristic of proteins. Intrinsically disordered proteins (IDPs) and denatured state ensembles are extreme manifestations of this heterogeneity. Inferences regarding globule versus coil formation can be drawn from analysis of polymeric properties such as average size, shape, and density fluctuations. Here we introduce a new parameter to quantify the degree of conformational heterogeneity within an ensemble to complement polymeric descriptors. The design of this parameter is guided by the need to distinguish between systems that couple their unfolding-folding transitions with coil-to-globule transitions and those systems that undergo coil-to-globule transitions with no evidence of acquiring a homogeneous ensemble of conformations upon collapse. The approach is as follows: Each conformation in an ensemble is converted into a conformational vector where the elements are inter-residue distances. Similarity between pairs of conformations is quantified using the projection between the corresponding conformational vectors. An ensemble of conformations yields a distribution of pairwise projections, which is converted into a distribution of pairwise conformational dissimilarities. The first moment of this dissimilarity distribution is normalized against the first moment of the distribution obtained by comparing conformations from the ensemble of interest to conformations drawn from a Flory random coil model. The latter sets an upper bound on conformational heterogeneity thus ensuring that the proposed measure for intra-ensemble heterogeneity is properly calibrated and can be used to compare ensembles for different sequences and across different temperatures. The new measure of conformational heterogeneity will be useful in quantitative studies of coupled folding and binding of IDPs and in de novo sequence design efforts that are geared toward controlling the degree of heterogeneity in unbound forms of IDPs.

  4. GEOLOGY & GEOPHYSICS 2014-2015

    E-print Network

    Bermúdez, José Luis

    GEOLOGY & GEOPHYSICS 2014-2015 Graduate Student Handbook - 1 · Geology & Geophysics Core Values - 2 · A Message from the Graduate Advisor - 3 · Department Organizations - 60 · Departmental Executive Committee - 61 · Geology& Geophysics Development Advisory Council

  5. Essential Elements of Geologic Reports.

    ERIC Educational Resources Information Center

    Webb, Elmer James

    1988-01-01

    Described is a report outline for geologic reports. Essential elements include title; abstract; introduction; stratigraphy; petrography; geochemistry; petrology; geophysics; structural geology; geologic history; modeling; economics; conclusions; and recommendations. (Author/CW)

  6. Experimental investigation of supercritical CO2 trapping mechanisms at the Intermediate Laboratory Scale in well-defined heterogeneous porous media

    SciTech Connect

    Trevisan, Luca; Pini, Ronny; Cihan, Abdullah; Birkholzer, Jens T.; Zhou, Quanlin; Illangasekare, Tissa H.

    2014-12-31

    The heterogeneous nature of typical sedimentary formations can play a major role in the propagation of the CO2 plume, eventually dampening the accumulation of mobile phase underneath the caprock. From core flooding experiments, it is also known that contrasts in capillary threshold pressure due to different pore size can affect the flow paths of the invading and displaced fluids and consequently influence the build- up of non-wetting phase (NWP) at interfaces between geological facies. The full characterization of the geologic variability at all relevant scales and the ability to make observations on the spatial and temporal distribution of the migration and trapping of supercritical CO2 is not feasible from a practical perspective. To provide insight into the impact of well-defined heterogeneous systems on the flow dynamics and trapping efficiency of supercritical CO2 under drainage and imbibition conditions, we present an experimental investigation at the meter scale conducted in synthetic sand reservoirs packed in a quasi-two-dimensional flow-cell. Two immiscible displacement experiments have been performed to observe the preferential entrapment of NWP in simple heterogeneous porous media. The experiments consisted of an injection, a fluid redistribution, and a forced imbibition stages conducted in an uncorrelated permeability field and a homogeneous base case scenario. We adopted x-ray attenuation analysis as a non-destructive technique that allows a precise measurement of phase saturations throughout the entire flow domain. By comparing a homogeneous and a heterogeneous scenario we have identified some important effects that can be attributed to capillary barriers, such as dampened plume advancement, higher non-wetting phase saturations, larger contact area between the injected and displaced phases, and a larger range of non-wetting phase saturations.

  7. On stochastic modeling of flow in multimodal heterogeneous Zhiming Lu and Dongxiao Zhang

    E-print Network

    Lu, Zhiming

    On stochastic modeling of flow in multimodal heterogeneous formations Zhiming Lu and Dongxiao Zhang Citation: Lu, Z., and D. Zhang, On stochastic modeling of flow in multimodal heterogeneous formations have been developed [e.g., Dagan, 1989; Gelhar, 1993; Zhang, 2002]. Most of these models, however

  8. Use of geological mapping tools to improve the hydraulic performance of SuDS.

    PubMed

    Bockhorn, Britta; Klint, Knud Erik Strøyberg; Jensen, Marina Bergen; Møller, Ingelise

    2015-01-01

    Most cities in Denmark are situated on low permeable clay rich deposits. These sediments are of glacial origin and range among the most heterogeneous, with hydraulic conductivities spanning several orders of magnitude. This heterogeneity has obvious consequences for the sizing of sustainable urban drainage systems (SuDS). We have tested methods to reveal geological heterogeneity at field scale to identify the most suitable sites for the placement of infiltration elements and to minimize their required size. We assessed the geological heterogeneity of a clay till plain in Eastern Jutland, Denmark measuring the shallow subsurface resistivity with a geoelectrical multi-electrode system. To confirm the resistivity data we conducted a spear auger mapping. The exposed sediments ranged from clay tills over sandy clay tills to sandy tills and correspond well to the geoelectrical data. To verify the value of geological information for placement of infiltration elements we carried out a number of infiltration tests on geologically different areas across the field, and we observed infiltration rates two times higher in the sandy till area than in the clay till area, thus demonstrating that the hydraulic performance of SuDS can be increased considerably and oversizing avoided if field geological heterogeneity is revealed before placing SuDS. PMID:26442491

  9. Fundamentals of Structural Geology

    NASA Astrophysics Data System (ADS)

    Pollard, David D.; Fletcher, Raymond C.

    2005-09-01

    Fundamentals of Structural Geology provides a new framework for the investigation of geological structures by integrating field mapping and mechanical analysis. Assuming a basic knowledge of physical geology, introductory calculus and physics, it emphasizes the observational data, modern mapping technology, principles of continuum mechanics, and the mathematical and computational skills, necessary to quantitatively map, describe, model, and explain deformation in Earth's lithosphere. By starting from the fundamental conservation laws of mass and momentum, the constitutive laws of material behavior, and the kinematic relationships for strain and rate of deformation, the authors demonstrate the relevance of solid and fluid mechanics to structural geology. This book offers a modern quantitative approach to structural geology for advanced students and researchers in structural geology and tectonics. It is supported by a website hosting images from the book, additional colour images, student exercises and MATLAB scripts. Solutions to the exercises are available to instructors. The book integrates field mapping using modern technology with the analysis of structures based on a complete mechanics MATLAB is used to visualize physical fields and analytical results and MATLAB scripts can be downloaded from the website to recreate textbook graphics and enable students to explore their choice of parameters and boundary conditions The supplementary website hosts color images of outcrop photographs used in the text, supplementary color images, and images of textbook figures for classroom presentations The textbook website also includes student exercises designed to instill the fundamental relationships, and to encourage the visualization of the evolution of geological structures; solutions are available to instructors

  10. Evidence of influence of regional and local heterogeneities within a chalk karst aquifer based on nitrates and chlorides analysis

    NASA Astrophysics Data System (ADS)

    El Janyani, S.; Dupont, J. P.; Massei, N.; Dörfliger, N.

    2012-04-01

    In Upper Normandy, a region located in the western Paris Basin, the main source of drinking water comes from the karst aquifer. Developing under the chalk plateaus, it is a covered aquifer overlaid by superficial formations of clay-with-flints and loess. Clay-with-flints result from chalk weathering whereas loess are wind periglacial deposits. The local geologic and hydrogelogic contexts are characterized by a mature development of sinkholes. The chalk karst is causing turbidity, often linked to the fast infiltration of surface water, carrying the products of river and slope erosion and associated contaminants into the aquifer through the sinkholes. Several authors have shown the potential of turbidity as a marker of suspended elements transport and karst conduits fast transport. In this study, we conducted monthly monitoring of 11 boreholes located in the upstream watershed near boreholes (surveyed by the French Geological Survey BRGM): Graveron-Semerville in the Southern department of Upper Normandy (Eure) and Rocquemont in the Norhtern department of Upper Normandy (Seine-Maritime). The monitoring carried out included water level and electrical conductivity (reflecting total water mineralization) measurements, and major elements analysis. In any case, the water levels are similar over time (in accordance with the reference borehole). High mineralizations are observed in the Eure boreholes with significant anomalies of nitrate (70 to 130 mg/l ) and chloride (35 to 90 mg/l). For the Seine Maritime boreholes, no anomalies in nitrates and chlorides were found. To explain such differences, the agricultural activities are not sufficiently different from the study site. The explanation would then come from different reservoirs involved in water storage: loessic formations, thicker and more spreaded in the Seine Maritime department and clay with flints, of significantly higher thickness on average in the Eure department. We also discuss the influence of the drainage network (input karst more or less connected to output karst) on the water ressource heterogeneity, including storage of contaminants (nitrates and chlorides) within the saturated zone of the chalk aquifer. This demonstrates two scales of heterogeneities in the chalk aquifer water masses at work in the ground water flow and transport: (i) the regional scale linked to the geological context and (ii) the watershed scale linked to the influence of the karst network. Accounting for these heterogeneities in the framework of a regional conceptual model will give a better understanding of the hydrological functioning of the chalk aquifer. This model will also serve as a basis for the parametrization of a physically-based numerical groundwater flow model presently under development. Keywords: Clay-with-Flints, loess, chalk aquifer, sinkholes, nitrates, chlorides, Upper Normandy.

  11. Heterogeneous conductorlike solvation model

    NASA Astrophysics Data System (ADS)

    Si, Dejun; Li, Hui

    2009-07-01

    A heterogeneous conductorlike solvation model (conductorlike screening model/conductorlike polarizable continuum model) that uses different local effective dielectrics for different portions of the solute cavity surface is implemented for quantum chemical Hartree-Fock and Kohn-Sham methods. A variational treatment is used to form the heterogeneous solvation operator, so a simple analytic expression of the energy gradients, which are vital for geometry optimization and molecular dynamics simulation, is derived and implemented. Using the new Fixed Points with Variable Areas surface tessellation scheme, continuous and smooth potential energy surfaces as well as analytic gradients are obtained for this heterogeneous model. Application of the heterogeneous solvation model to a realistic quantum model consisting of 101 atoms for the type-1 Cu center in rusticyanin shows that the desolvation due to protein burial can likely raise the reduction potential by ˜200 mV and, including the heterogeneity in geometry optimization, can likely affect the results by ˜2 kcal/mol or ˜70 mV.

  12. A bibliography of planetary geology principal investigators and their associates, 1976-1978

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This bibliography cites publications submitted by 484 principal investigators and their associates who were supported through NASA's Office of Space Sciences Planetary Geology Program. Subject classifications include: solar system formation, comets, and asteroids; planetary satellites, planetary interiors, geological and geochemical constraints on planetary evolution; impact crater studies, volcanism, eolian studies, fluvian studies, Mars geological mapping; Mercury geological mapping; planetary cartography; and instrument development and techniques. An author/editor index is provided.

  13. Geologic map of the Dillon 1 degree by 2 degrees Quadrangle, Idaho and Montana

    USGS Publications Warehouse

    Ruppel, E.T.; Lopez, D.A.; O'Neill, J. M.

    1993-01-01

    The digital ARC/INFO databases included in this website provide a GIS database for the geologic map of the Dillon 1 degree by 2 degree quadrangle of southwest Montana and east-central Idaho. The geologic map was originally published as U.S. Geological Survey Miscellaneous Investigations Series Map I-1803-H. This website directory contains ARC/INFO format files that can be used to query or display the geology of USGS Map I-1803-H with GIS software.

  14. Chapter 6. Tabular data and graphical images in support of the U.S. Geological Survey National Oil and Gas Assessment-East Texas basin and Louisiana-Mississippi salt basins provinces, Jurassic Smackover interior salt basins total petroleum system (504902), Travis Peak and Hosston formations.

    USGS Publications Warehouse

    U.S. Geological Survey

    2006-01-01

    This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on the CD-ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Because of the number and variety of platforms and software available, graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files).

  15. A multiple-point geostatistical approach to quantifying uncertainty for flow and transport simulation in geologically complex environments

    NASA Astrophysics Data System (ADS)

    Cronkite-Ratcliff, C.; Phelps, G. A.; Boucher, A.

    2011-12-01

    In many geologic settings, the pathways of groundwater flow are controlled by geologic heterogeneities which have complex geometries. Models of these geologic heterogeneities, and consequently, their effects on the simulated pathways of groundwater flow, are characterized by uncertainty. Multiple-point geostatistics, which uses a training image to represent complex geometric descriptions of geologic heterogeneity, provides a stochastic approach to the analysis of geologic uncertainty. Incorporating multiple-point geostatistics into numerical models provides a way to extend this analysis to the effects of geologic uncertainty on the results of flow simulations. We present two case studies to demonstrate the application of multiple-point geostatistics to numerical flow simulation in complex geologic settings with both static and dynamic conditioning data. Both cases involve the development of a training image from a complex geometric description of the geologic environment. Geologic heterogeneity is modeled stochastically by generating multiple equally-probable realizations, all consistent with the training image. Numerical flow simulation for each stochastic realization provides the basis for analyzing the effects of geologic uncertainty on simulated hydraulic response. The first case study is a hypothetical geologic scenario developed using data from the alluvial deposits in Yucca Flat, Nevada. The SNESIM algorithm is used to stochastically model geologic heterogeneity conditioned to the mapped surface geology as well as vertical drill-hole data. Numerical simulation of groundwater flow and contaminant transport through geologic models produces a distribution of hydraulic responses and contaminant concentration results. From this distribution of results, the probability of exceeding a given contaminant concentration threshold can be used as an indicator of uncertainty about the location of the contaminant plume boundary. The second case study considers a characteristic lava-flow aquifer system in Pahute Mesa, Nevada. A 3D training image is developed by using object-based simulation of parametric shapes to represent the key morphologic features of rhyolite lava flows embedded within ash-flow tuffs. In addition to vertical drill-hole data, transient pressure head data from aquifer tests can be used to constrain the stochastic model outcomes. The use of both static and dynamic conditioning data allows the identification of potential geologic structures that control hydraulic response. These case studies demonstrate the flexibility of the multiple-point geostatistics approach for considering multiple types of data and for developing sophisticated models of geologic heterogeneities that can be incorporated into numerical flow simulations.

  16. Production Data Integration into High Resolution Geologic Models with Trajectory-based Methods and A Dual Scale Approach 

    E-print Network

    Kim, Jong Uk

    2012-02-14

    the essential features of the geologic model. To begin with, we sequentially coarsen the fine-scale geological model by grouping layers in such a way that the heterogeneity measure of an appropriately defined 'static' property is minimized within the layers...

  17. Constructing a Geology Ontology Using a Relational Database

    NASA Astrophysics Data System (ADS)

    Hou, W.; Yang, L.; Yin, S.; Ye, J.; Clarke, K.

    2013-12-01

    In geology community, the creation of a common geology ontology has become a useful means to solve problems of data integration, knowledge transformation and the interoperation of multi-source, heterogeneous and multiple scale geological data. Currently, human-computer interaction methods and relational database-based methods are the primary ontology construction methods. Some human-computer interaction methods such as the Geo-rule based method, the ontology life cycle method and the module design method have been proposed for applied geological ontologies. Essentially, the relational database-based method is a reverse engineering of abstracted semantic information from an existing database. The key is to construct rules for the transformation of database entities into the ontology. Relative to the human-computer interaction method, relational database-based methods can use existing resources and the stated semantic relationships among geological entities. However, two problems challenge the development and application. One is the transformation of multiple inheritances and nested relationships and their representation in an ontology. The other is that most of these methods do not measure the semantic retention of the transformation process. In this study, we focused on constructing a rule set to convert the semantics in a geological database into a geological ontology. According to the relational schema of a geological database, a conversion approach is presented to convert a geological spatial database to an OWL-based geological ontology, which is based on identifying semantics such as entities, relationships, inheritance relationships, nested relationships and cluster relationships. The semantic integrity of the transformation was verified using an inverse mapping process. In a geological ontology, an inheritance and union operations between superclass and subclass were used to present the nested relationship in a geochronology and the multiple inheritances relationship. Based on a Quaternary database of downtown of Foshan city, Guangdong Province, in Southern China, a geological ontology was constructed using the proposed method. To measure the maintenance of semantics in the conversation process and the results, an inverse mapping from the ontology to a relational database was tested based on a proposed conversation rule. The comparison of schema and entities and the reduction of tables between the inverse database and the original database illustrated that the proposed method retains the semantic information well during the conversation process. An application for abstracting sandstone information showed that semantic relationships among concepts in the geological database were successfully reorganized in the constructed ontology. Key words: geological ontology; geological spatial database; multiple inheritance; OWL Acknowledgement: This research is jointly funded by the Specialized Research Fund for the Doctoral Program of Higher Education of China (RFDP) (20100171120001), NSFC (41102207) and the Fundamental Research Funds for the Central Universities (12lgpy19).

  18. Semantic mediation in the national geologic map database (US)

    USGS Publications Warehouse

    Percy, D.; Richard, S.; Soller, D.

    2008-01-01

    Controlled language is the primary challenge in merging heterogeneous databases of geologic information. Each agency or organization produces databases with different schema, and different terminology for describing the objects within. In order to make some progress toward merging these databases using current technology, we have developed software and a workflow that allows for the "manual semantic mediation" of these geologic map databases. Enthusiastic support from many state agencies (stakeholders and data stewards) has shown that the community supports this approach. Future implementations will move toward a more Artificial Intelligence-based approach, using expert-systems or knowledge-bases to process data based on the training sets we have developed manually.

  19. Managing Power Heterogeneity

    NASA Astrophysics Data System (ADS)

    Pruhs, Kirk

    A particularly important emergent technology is heterogeneous processors (or cores), which many computer architects believe will be the dominant architectural design in the future. The main advantage of a heterogeneous architecture, relative to an architecture of identical processors, is that it allows for the inclusion of processors whose design is specialized for particular types of jobs, and for jobs to be assigned to a processor best suited for that job. Most notably, it is envisioned that these heterogeneous architectures will consist of a small number of high-power high-performance processors for critical jobs, and a larger number of lower-power lower-performance processors for less critical jobs. Naturally, the lower-power processors would be more energy efficient in terms of the computation performed per unit of energy expended, and would generate less heat per unit of computation. For a given area and power budget, heterogeneous designs can give significantly better performance for standard workloads. Moreover, even processors that were designed to be homogeneous, are increasingly likely to be heterogeneous at run time: the dominant underlying cause is the increasing variability in the fabrication process as the feature size is scaled down (although run time faults will also play a role). Since manufacturing yields would be unacceptably low if every processor/core was required to be perfect, and since there would be significant performance loss from derating the entire chip to the functioning of the least functional processor (which is what would be required in order to attain processor homogeneity), some processor heterogeneity seems inevitable in chips with many processors/cores.

  20. Lattice Boltzmann simulation of immiscible fluid displacement in porous media: Homogeneous versus heterogeneous pore network

    SciTech Connect

    Liu, Haihu; Zhang, Yonghao; Valocchi, Albert J.

    2015-05-15

    Injection of anthropogenic carbon dioxide (CO{sub 2}) into geological formations is a promising approach to reduce greenhouse gas emissions into the atmosphere. Predicting the amount of CO{sub 2} that can be captured and its long-term storage stability in subsurface requires a fundamental understanding of multiphase displacement phenomena at the pore scale. In this paper, the lattice Boltzmann method is employed to simulate the immiscible displacement of a wetting fluid by a non-wetting one in two microfluidic flow cells, one with a homogeneous pore network and the other with a randomly heterogeneous pore network. We have identified three different displacement patterns, namely, stable displacement, capillary fingering, and viscous fingering, all of which are strongly dependent upon the capillary number (Ca), viscosity ratio (M), and the media heterogeneity. The non-wetting fluid saturation (S{sub nw}) is found to increase nearly linearly with logCa for each constant M. Increasing M (viscosity ratio of non-wetting fluid to wetting fluid) or decreasing the media heterogeneity can enhance the stability of the displacement process, resulting in an increase in S{sub nw}. In either pore networks, the specific interfacial length is linearly proportional to S{sub nw} during drainage with equal proportionality constant for all cases excluding those revealing considerable viscous fingering. Our numerical results confirm the previous experimental finding that the steady state specific interfacial length exhibits a linear dependence on S{sub nw} for either favorable (M ? 1) or unfavorable (M < 1) displacement, and the slope is slightly higher for the unfavorable displacement.

  1. Origins of Anomalous Transport in Heterogeneous Media: Structural and Dynamic Controls

    NASA Astrophysics Data System (ADS)

    Edery, Yaniv; Guadagnini, Alberto; Scher, Harvey; Berkowitz, Brian

    2014-05-01

    Anomalous (or 'non-Fickian') transport is ubiquitous in the context of tracer migration in geological formations. We quantitatively identify the origin of anomalous transport in a representative model of a heterogeneous porous medium under uniform (in the mean) flow conditions; we focus on anomalous transport which arises in the complex flow patterns of lognormally distributed hydraulic conductivity (K) fields, with several decades of K values. Transport in the domains is determined by a particle tracking technique and characterized by breakthrough curves (BTCs). The BTC averaged over multiple realizations demonstrates anomalous transport in all cases, which is accounted for entirely by a power-law distribution ~ t-1-? of local transition times, contained in the probability density function ?(t) of transition times, using the framework of a continuous time random walk (CTRW). A unique feature of our analysis is the derivation of ?(t) as a function of parameters quantifying the heterogeneity of the domain. In this context, we first establish the dominance of preferential pathways across each domain, and characterize the statistics of these pathways by forming a particle-visitation weighted histogram Hw(K). By converting the ln(K) dependence of Hw(K) into time, we demonstrate the equivalence of Hw(K) and ?(t), and delineate the region of Hw(K) that forms the power law of ?(t). This thus defines the origin of anomalous transport. Analysis of the preferential pathways clearly demonstrates the limitations of critical path analysis and percolation theory as a basis for determining the origin of anomalous transport. Furthermore, we derive an expression defining the power law exponent ? in terms of the Hw(K) parameters. The equivalence between Hw(K) and ?(t) is a remarkable result, particularly given the nature of the K heterogeneity, the complexity of the flow field within each realization, and the statistics of the particle transitions.

  2. Origins of anomalous transport in heterogeneous media: Structural and dynamic controls

    NASA Astrophysics Data System (ADS)

    Edery, Yaniv; Guadagnini, Alberto; Scher, Harvey; Berkowitz, Brian

    2014-02-01

    Anomalous (or "non-Fickian") transport is ubiquitous in the context of tracer migration in geological formations. We quantitatively identify the origin of anomalous transport in a representative model of a heterogeneous porous medium under uniform (in the mean) flow conditions; we focus on anomalous transport which arises in the complex flow patterns of lognormally distributed hydraulic conductivity (K) fields, with several decades of K values. Transport in the domains is determined by a particle tracking technique and characterized by breakthrough curves (BTCs). The BTC averaged over multiple realizations demonstrates anomalous transport in all cases, which is accounted for entirely by a power law distribution ˜t-1-? of local transition times. The latter is contained in the probability density function ?(t) of transition times, embedded in the framework of a continuous time random walk (CTRW). A unique feature of our analysis is the derivation of ?(t) as a function of parameters quantifying the heterogeneity of the domain. In this context, we first establish the dominance of preferential pathways across each domain, and characterize the statistics of these pathways by forming a particle-visitation weighted histogram, Hw>(K>), of the hydraulic conductivity. By converting the ln(K) dependence of Hw>(K>) into time, we demonstrate the equivalence of Hw>(K>) and ?(t), and delineate the region of Hw>(K>) that forms the power law of ?(t). This thus defines the origin of anomalous transport. Analysis of the preferential pathways clearly demonstrates the limitations of critical path analysis and percolation theory as a basis for determining the origin of anomalous transport. Furthermore, we derive an expression defining the power law exponent ? in terms of the Hw>(K>) parameters. The equivalence between Hw>(K>) and ?(t) is a remarkable result, particularly given the nature of the K heterogeneity, the complexity of the flow field within each realization, and the statistics of the particle transitions.

  3. Scaling the Geologic Past

    ERIC Educational Resources Information Center

    Gerritts, Mary

    1975-01-01

    Describes construction of a Geologic Time Scale on a 100 foot roll of paper and suggests activities concerning its use. Includes information about fossils and suggestions for conducting a fossil field trip with students. (BR)

  4. Experiencing Structural Geology

    ERIC Educational Resources Information Center

    Davis, George H.

    1978-01-01

    Describes an undergraduate structural geology course that incorporates field lab time and research. Lectures, outside readings, and in-class experimentation are coordinated with the field work to prepare a scientific report. (MA)

  5. Stratigraphy and structural geology

    NASA Technical Reports Server (NTRS)

    Carr, M. H.; Wilhelms, D. E.; Greeley, R.; Guest, J. E.

    1976-01-01

    The immediate goal of stratigraphy and structural geology is to reduce the enormous complexity of a planetary surface to comprehensible proportions by dividing the near-surface rocks into units and mapping their distribution and attitude.

  6. Mass Extinctions Geology 331

    E-print Network

    Kammer, Thomas

    ;Stromatoporoids and Corals sarv.gi.ee/geology/photos.html #12;Rugose Corals #12;Victims · Permian ­ about 50 brachiopods ­ All rugose and tabulate corals ­ All remaining trilobites ­ Nearly all crinoids ­ Nearly all

  7. Economic Geology (Oil & Gas)

    ERIC Educational Resources Information Center

    Geotimes, 1972

    1972-01-01

    Briefly reviews the worldwide developments in petroleum geology in 1971, including exploration, new fields, and oil production. This report is condensed from the October Bulletin of the American Association of Petroleum Geologists. (PR)

  8. Digital geologic map of Yellowstone National Park, Idaho, Montana, Wyoming and vicinity

    USGS Publications Warehouse

    Christiansen, Robert L.; Wahl, Ronald R.

    1999-01-01

    The geology coverage was developed from the 1972 USGS Geologic Map of Yellowstone National Park. It contains polygons of bedrock formations, dikes, and faults. Errors in the 1972 map were corrected and an area outside the Park boundary on the west and south was added. Attributes attached to each polygon include a formation code, formation name, formation age, and a generalized unit name. Line attributes include water, contacts, and faults. Updated information includes a break down of Tertiary, and Quaternary volcanic rock units.

  9. Geologic exploration of Mars

    NASA Technical Reports Server (NTRS)

    Plescia, J. B.

    1990-01-01

    The scientific objectives and methods involved in a geologic exploration of Mars from a manned outpost are discussed. The constraints on outpost activities imposed by the limited crew size, limited amount of time available for science, the limited diversity of scientific expertise, and the competition between scientific disciplines are addressed. Three examples of possible outpost locations are examined: the Olympus Mons aureole, Mangala Valles/Daedalia Planum, and Candor Chasma. The geologic work that could be done at each site is pointed out.

  10. NADM Conceptual Model 1.0 -- A Conceptual Model for Geologic Map Information

    USGS Publications Warehouse

    North American Geologic Map Data Model (NADM) Steering Committee Data Model Design Team

    2004-01-01

    Executive Summary -- The NADM Data Model Design Team was established in 1999 by the North American Geologic Map Data Model Steering Committee (NADMSC) with the purpose of drafting a geologic map data model for consideration as a standard for developing interoperable geologic map-centered databases by state, provincial, and federal geological surveys. The model is designed to be a technology-neutral conceptual model that can form the basis for a web-based interchange format using evolving information technology (e.g., XML, RDF, OWL), and guide implementation of geoscience databases in a common conceptual framework. The intended purpose is to allow geologic information sharing between geologic map data providers and users, independent of local information system implementation. The model emphasizes geoscience concepts and relationships related to information presented on geologic maps. Design has been guided by an informal requirements analysis, documentation of existing databases, technology developments, and other standardization efforts in the geoscience and computer-science communities. A key aspect of the model is the notion that representation of the conceptual framework (ontology) that underlies geologic map data must be part of the model, because this framework changes with time and understanding, and varies between information providers. The top level of the model distinguishes geologic concepts, geologic representation concepts, and metadata. The geologic representation part of the model provides a framework for representing the ontology that underlies geologic map data through a controlled vocabulary, and for establishing the relationships between this vocabulary and a geologic map visualization or portrayal. Top-level geologic classes in the model are Earth material (substance), geologic unit (parts of the Earth), geologic age, geologic structure, fossil, geologic process, geologic relation, and geologic event.

  11. Magma Differentiation within Lithospheric Mantle: a Possible Source for Mantle Heterogeneity

    NASA Astrophysics Data System (ADS)

    Pilet, S.; Ulmer, P.; Villiger, S.; Ulianov, A.; Chemin, S.; Hernandez, J.

    2005-12-01

    Variations in radiogenic isotope composition observed in oceanic basalt indicate that the mantle is heterogeneous at large and small scales. The recycling of subducted oceanic crust with the addition of sediment is commonly considered to be responsible for the formation of these mantle heterogeneities [1]. Alternatively, these heterogeneities observed in the OIB source could be related to the recycling of a metasomatised lithosphere [2-5]. Following the model suggested by [5], compositional variation in the mantle source, necessary to generate time distinct end-member compositions, could be explained by an evolution of metasomatic vein compositions present in the recycled heterogeneous lithosphere.. However, the magmatic process that generates these veins remains unconstrained. Here we present new experimental data, combined with a study of mantle veins from the Pyrenees, which provide constraints on phase equilibria, solid and liquid compositions along the liquid line of descent of primary basanitic magmas at lithospheric mantle pressure. A series of hydrous experiments have been performed in an end-loaded piston cylinder apparatus on a primitive basanite at 1.5 GPa and temperatures in the range 1250-980°C. Near-perfect fractional crystallization was attained in a stepwise manner using 30°C temperature steps and starting compositions corresponding to the liquid composition of the previous, higher-temperature glass composition. The minerals that crystallized during these experiments varied from cpx + olivine (4:1) in mafic liquid compositions to amphibole + accessory phases (spinel, ilmenite and apatite) in more differentiated ones. Peralkaline liquid compositions were generated below 1040°C and are characterized by a low MgO and FeO tot content, but an extreme enrichment in Na2O, K2O and Al2O3. These enrichments can be explained by the lack of feldspar crystallization during all experiments. The mineralogical compositions of the Pyrenean mantle veins show clear similarities to the fractionated phases produced by the fractional crystallization experiments. The same transition from clinopyroxenite to hornblendite and the same range of Mg# variation is observed in vein and experimental minerals. The correlation between the decrease of Cr content in cpx or amphibole and the decrease of their respective Mg# indicate a clear disequilibrium of differentiated veins with the surrounding mantle. This suggests that the formation of anhydrous and hydrous veins could be linked by a differentiation process and that the formation of these mantle veins could be approximated by a fractional crystallization process. The evolution of trace elements from basic to differentiated veins confirms that it is possible to fractionate trace element ratios, such as Nb/La and U/Pb, in a metasomatized heterogeneous lithosphere. With time, the different parts of this lithosphere will evolve to distinct isotopic compositions. Furthermore, considering the extremely high degree of trace element enrichment in veins, a small percentage of veins could significantly modify the trace element "signature" of the lithospheric mantle without significantly altering whole mineral composition of this heterogeneous mantle. Such a mantle would be a perfect candidate for OIB formation. [1] Hofmann, White. 1982 EPSL 57, 421. [2] Halliday et al. 1995 EPSL 133, 379. [3] McKenzie, K.R. O'Nions. 1995 J. Petrol. 36, 133. [4] Nui, O'Hara. 2003 J. Geophys. Res.,108, B4, 2209. [5] Pilet et al. 2005 EPSL 236, 148. [6] Pilet et al. 2004 Geology, 32, 2, 113.

  12. BRITISH GEOLOGICAL SURVEY TECHNICAL REPORT

    E-print Network

    BRITISH GEOLOGICAL SURVEY TECHNICAL REPORT WM/00/17R Geomagnetism Series TTThhheee. Quinn, 2000. The Derivation of World Magnetic Model 2000. British Geological Survey Technical Report WM and John M. Quinn* (* at United States Geological Survey) #12;#12;BRITISH GEOLOGICAL SURVEY TECHNICAL

  13. Modeling the establishment of preferential flow during infiltration in a heterogeneous glaciofluvial deposit

    NASA Astrophysics Data System (ADS)

    Ben Slimene, Erij; Lassabatere, Laurent; Winiarski, Thierry; Gourdon, Remy

    2015-04-01

    Large cities are mostly situated in areas close to water resources in order to meet the water needs of their populations. Alluvial soils harbor large aquifers that are used to supply water, the Rhone-Alpes region being a good illustration. However, the increase of soil sealing has led to the development of best management practices such as infiltration basins which are aimed at infiltrating stormwater in order to reduce the amount of water collected and treated in usual systems. Yet, these infiltration basins are mainly settled over highly permeable geologic formations so as to ensure water infiltration and a proper functioning of these infiltration basins. Most of these formations are strongly heterogeneous, since they are made of different materials with contrasting sedimentological properties (e.g. particle size distribution) and transfer properties. This paper addresses flow modeling during the infiltration phase in the vadose zone underneath infiltration basins settled over a strongly heterogeneous glaciofluvial deposit. In particular, we want to pinpoint numerically the worst conditions with regards to preferential flow, in terms of initial hydric conditions (initial water contents) and imposed flow rates. For this purpose, a numerical study is proposed on the basis of previous studies offering a sedimentological description of the subsoil with the detail of its architecture and a precise description of the different lithofacies and their hydraulic properties. Considering this, we worked on a section (13.5m long and 2.5m high) for which a complete sedimentological and hydraulic description had already been performed. Water infiltration was modeled for different initial and boundary conditions (mostly the values of the flux imposed at surface). At first, different numerical tests and adjustments have been made including mesh optimization with regards to both accuracy and computation time. Following these tests, the "tight" mesh has been validated since it proved to be necessary for the detection of preferential flow. Then, a sensitivity analysis addressed the role of initial and boundary conditions on the establishment of preferential flow. According to these conditions, the time required to reach steady state over the whole soil profile, wetting fronts and water fluxes during transient state and water fluxes at steady state were accurately characterized and compared to those of a uniform section. These results are quite counter-intuitive and suggest that unsaturated flow can favor preferential flow, mostly for low water fluxes imposed at surface. In addition, these results are relevant with regards to ongoing researches on the fate of pollutants into heterogeneous deposits. These data are of a great interest since they allow generating a conceptual and numerical model to better understand and predict the development of preferential flows and their impact on pollutant transfer in highly heterogeneous glaciofluvial deposits.

  14. HETEROGENEOUS MODELING AND

    E-print Network

    California at Berkeley, University of

    PTOLEMY II HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA Edited by: Christopher Brooks TO PTOLEMY II Authors: Shuvra S. Bhattacharyya Christopher Brooks Elaine Cheong John Davis, II Mudit Goel of Electrical Engineering and Computer Sciences University of California at Berkeley http://ptolemy

  15. -PTOLEMY II -HETEROGENEOUS CONCURRENT

    E-print Network

    California at Berkeley, University of

    -PTOLEMY II - HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA John Davis, II Mudit Goel University of California at Berkeley http://ptolemy.eecs.berkeley.edu Memorandum UCB/ERL M99/40 Document Contents Part 1: Using Ptolemy II 1. Introduction 1-1 1.1.Modeling and Design 1-1 1.2.Architecture Design 1

  16. HETEROGENEOUS MODELING AND

    E-print Network

    California at Berkeley, University of

    PTOLEMY II HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA Edited by: Christopher Hylands of California at Berkeley http://ptolemy.eecs.berkeley.edu Document Version 2.0.1 for use with Ptolemy II 2 Concurrent Modeling and Design Contents Part 1: Using Ptolemy II 1. Introduction 1-1 1.1.Modeling and Design

  17. -PTOLEMY II -HETEROGENEOUS CONCURRENT

    E-print Network

    California at Berkeley, University of

    -PTOLEMY II - HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA John Davis, II Christopher of Electrical Engineering and Computer Sciences University of California at Berkeley http://ptolemy with Ptolemy II 1.0 March 15, 2001 This project is supported by the Defense Advanced Research Projects Agency

  18. HETEROGENEOUS MODELING AND

    E-print Network

    California at Berkeley, University of

    PTOLEMY II HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA Edited by: Christopher Hylands: INTRODUCTION TO PTOLEMY II Authors: Shuvra S. Bhattacharyya Elaine Cheong John Davis, II Mudit Goel Bart of Electrical Engineering and Computer Sciences University of California at Berkeley http://ptolemy

  19. Heterogeneous waste processing

    DOEpatents

    Vanderberg, Laura A. (Los Alamos, NM); Sauer, Nancy N. (Los Alamos, NM); Brainard, James R. (Los Alamos, NM); Foreman, Trudi M. (Los Alamos, NM); Hanners, John L. (Los Alamos, NM)

    2000-01-01

    A combination of treatment methods are provided for treatment of heterogeneous waste including: (1) treatment for any organic compounds present; (2) removal of metals from the waste; and, (3) bulk volume reduction, with at least two of the three treatment methods employed and all three treatment methods emplyed where suitable.

  20. Scales of mantle heterogeneity

    NASA Astrophysics Data System (ADS)

    Moore, J. C.; Akber-Knutson, S.; Konter, J.; Kellogg, J.; Hart, S.; Kellogg, L. H.; Romanowicz, B.

    2004-12-01

    A long-standing question in mantle dynamics concerns the scale of heterogeneity in the mantle. Mantle convection tends to both destroy (through stirring) and create (through melt extraction and subduction) heterogeneity in bulk and trace element composition. Over time, these competing processes create variations in geochemical composition along mid-oceanic ridges and among oceanic islands, spanning a range of scales from extremely long wavelength (for example, the DUPAL anomaly) to very small scale (for example, variations amongst melt inclusions). While geochemical data and seismic observations can be used to constrain the length scales of mantle heterogeneity, dynamical mixing calculations can illustrate the processes and timescales involved in stirring and mixing. At the Summer 2004 CIDER workshop on Relating Geochemical and Seismological Heterogeneity in the Earth's Mantle, an interdisciplinary group evaluated scales of heterogeneity in the Earth's mantle using a combined analysis of geochemical data, seismological data and results of numerical models of mixing. We mined the PetDB database for isotopic data from glass and whole rock analyses for the Mid-Atlantic Ridge (MAR) and the East Pacific Rise (EPR), projecting them along the ridge length. We examined Sr isotope variability along the East Pacific rise by looking at the difference in Sr ratio between adjacent samples as a function of distance between the samples. The East Pacific Rise exhibits an overall bowl shape of normal MORB characteristics, with higher values in the higher latitudes (there is, however, an unfortunate gap in sampling, roughly 2000 km long). These background characteristics are punctuated with spikes in values at various locations, some, but not all of which are associated with off-axis volcanism. A Lomb-Scargle periodogram for unevenly spaced data was utilized to construct a power spectrum of the scale lengths of heterogeneity along both ridges. Using the same isotopic systems (Sr, Nd and Pb), we correlated isotopic data from oceanic islands and seamounts with geophysical measurements and observations in order to determine whether the mantle source component end-members are related to geophysical structure. For this, data obtained from the GeoROC database and other sources were first carefully examined for consistency and then correlated with recent global upper mantle tomographic models of seismic attenuation and velocity structure. Complementing this approach is a fractal analysis of dynamical models of mantle mixing. A variety of published numerical mixing models show a fractal distribution of heterogeneities, consistent with a marble-cake mantle.

  1. Abstracts of the Annual Meeting of Planetary Geologic Mappers, Flagstaff, AZ, 2010

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L. (Editor); Kelley, Michael S. (Editor)

    2010-01-01

    Topics covered include: Detailed Analysis of the Intra-Ejecta Dark Plains of Caloris Basin, Mercury; The Formation and Evolution of Tessera and Insights into the Beginning of Recorded History on Venus: Geology of the Fortuna Tessera Quadrangle (V-2); Geologic Map of the Snegurochka Planitia Quadrangle (V-1): Implications for the Volcanic History of the North Polar Region of Venus; Geological Map of the Fredegonade (V-57) Quadrangle, Venus: Status Report; Geologic Mapping of V-19; Geology of the Lachesis Tessera Quadrangle (V-18), Venus; Comparison of Mapping Tessera Terrain in the Phoebe Regio (V-41) and Tellus Tessera (V-10) Quadrangles; Geologic Mapping of the Devana Chasma (V-29) Quadrangle, Venus; Geologic Mapping of the Aristarchus Plateau Region on the Moon; Geologic Mapping of the Lunar South Pole Quadrangle (LQ-30); The Pilot Lunar Geologic Mapping Project: Summary Results and Recommendations from the Copernicus Quadrangle; Geologic Mapping of the Nili Fossae Region of Mars: MTM Quadrangles 20287, 20282, 25287, 25282, 30287, and 30282; Geologic Mapping of the Mawrth Vallis Region, Mars: MTM Quadrangles 25022, 25017, 25012, 20022, 20017, and 20012; Evidence for an Ancient Buried Landscape on the NW Rim of Hellas Basin, Mars; New Geologic Map of the Argyre Region of Mars: Deciphering the Geologic History Through Mars Global Surveyor, Mars Odyssey, and Mars Express Data; Geologic Mapping in the Hesperia Planum Region of Mars; Geologic Mapping of the Meridiani Region of Mars; Geologic Mapping in Southern Margaritifer Terra; Geology of -30247, -35247, and -40247 Quadrangles, Southern Hesperia Planum, Mars; The Interaction of Impact Melt, Impact-Derived Sediment, and Volatiles at Crater Tooting, Mars; Geologic Map of the Olympia Cavi Region of Mars (MTM 85200): A Summary of Tactical Approaches; Geology of the Terra Cimmeria-Utopia Planitia Highland Lowland Transitional Zone: Final Technical Approach and Scientific Results; Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: First Year Results and Second Year Work Plan; Mars Global Geologic Mapping Progress and Suggested Geographic-Based Hierarchal Systems for Unit Grouping and Naming; Progress in the Scandia Region Geologic Map of Mars; Geomorphic Mapping of MTMS -20022 and -20017; Geologic Mapping of the Medusae Fossae Formation, Mars, and the Northern Lowland Plains, Venus; Volcanism on Io: Results from Global Geologic Mapping; Employing Geodatabases for Planetary Mapping Conduct - Requirements, Concepts and Solutions; and Planetary Geologic Mapping Handbook - 2010.

  2. Geologic effects of hurricanes

    NASA Astrophysics Data System (ADS)

    Coch, Nicholas K.

    1994-08-01

    Hurricanes are intense low pressure systems of tropical origin. Hurricane damage results from storm surge, wind, and inland flooding from heavy rainfall. Field observations and remote sensing of recent major hurricanes such as Hugo (1989), Andrew (1992) and Iniki (1992) are providing new insights into the mechanisms producing damage in these major storms. Velocities associated with hurricanes include the counterclockwise vortex winds flowing around the eye and the much slower regional winds that steer hurricane and move it forward. Vectorial addition of theseof these two winds on the higher effective wind speed than on the left side. Coast-parallel hurricane tracks keep the weaker left side of the storm against the coast, whereas coast-normal tracks produce a wide swath of destruction as the more powerful right side of the storm cuts a swath of destruction hundreds of kilometers inland. Storm surge is a function of the wind speed, central pressure, shelf slope, shoreline configuration, and anthropogenic alterations to the shoreline. Maximum surge heights are not under the eye of the hurricane, where the pressure is lowest, but on the right side of the eye at the radius of maximum winds, where the winds are strongest. Flood surge occurs as the hurricane approaches land and drives coastal waters, and superimposed waves, across the shore. Ebb surge occurs when impounded surface water flows seaward as the storm moves inland. Flood and ebb surge damage have been greatly increased in recent hurricanes as a result of anthropogenic changes along the shoreline. Hurricane wind damage occurs on three scales — megascale, mesoscale and microscale. Local wind damage is a function of wind speed, exposure and structural resistance to velocity pressure, wind drag and flying debris. Localized extreme damage is caused by gusts that can locally exceed sustained winds by a factor of two in areas where there is strong convective activity. Geologic changes occuring in hurricanes include beach erosion, dune erosion, inlet formation from flood and ebb surge, landscape changes through tree destruction by wind and nearshore channeling and sedimentation resulting from ebb surge. Multi-decadal wet and dry cycles in West Africa seem to be associated with increases (wet periods) and decreases (dry periods) in the frequency of Atlantic Coast landfalling hurricanes. Coastalzone population and development has increased markedly in a time of low hurricane frequency in the 24 year dry cycle from1970 to the present. However, no previous climatic cycle in this century has exceeded 26 years. We may entering a multi-decadal cycle of greater hurricane activity, placing these highly urbanized shorelines in considerable danger.

  3. Characterization of Physical and Hydro-Geological Properties of Kanamaru Research Site in Japan

    NASA Astrophysics Data System (ADS)

    Takeda, M.; Zhang, M.; Takeno, N.; Watanabe, Y.

    2004-12-01

    Establishing the comprehensive knowledge of applicability of the methods for investigating hydraulic properties of low permeability geologic strata is an urgent issue for supporting regulation of geological disposal of nuclear waste in the near future. As a beginning of this work, a systematic examination of various kinds of techniques for hydro-geological surveys has been started in Kanamaru Research Site in Japan. This paper briefly introduces the research plan and preliminary results obtained from the first year of investigation. The survey techniques include borehole excavation, borehole imaging, gamma-ray, caliper, acoustic, electrical resistivity and density loggings, permeability tests and flow direction measurement using a single borehole, permeability tests and flow direction measurement using multi boreholes, etc. Preliminary findings can be summarized as follows: (1) The stratigraphy at the survey area consists of topsoil, debris sediments, sandstone, mudstone, conglomeratic sandstone, mudstone, arkose sandstone, and granite. High uranium concentrations are detected at lower portion of the conglomeratic sandstone by gamma-ray logging. (2) The survey area is located at a slope inclined from the north to the south, and the dominant groundwater flow is considered to be in the direction form the north to the south. And the downward flow was also recognized by the flow direction measurements and water quality logging. (3) Hydraulic conductivities derived from permeability tests using a single borehole were in the range of 5E-10 to 1E-7 m/s. The hydraulic conductivities of the same lithology derived from different boreholes varied, and the discrepancies were up to an order. This result indicates that the formations in the survey area have hydraulic heterogeneity in both the vertical and horizontal directions. (4) On the whole, stratum with fast velocity of elastic wave showed large resistivity and low permeability. The degree of correlation between the hydraulic and physical properties was different for each stratum.

  4. Characterization of heterogeneities from core X-ray scans and borehole wall images in a reefal carbonate reservoir: influence on the porosity structure.

    NASA Astrophysics Data System (ADS)

    Hebert, V.; Garing, C.; Pezard, P. A.; Gouze, P.; Maria-Sube, Y.; Camoin, G.; Lapointe, P.

    2009-04-01

    Petrophysical properties of rocks can be largely influenced by heterogeneities. This is particularly true in reefal carbonates, with heterogeneities due to the primary structure of the reef, the degradation of that structure into a fossil form, and fluid circulations with associated dissolutions and recrystallization. We report here a study conducted on Miocene reefal carbonates drilled in the context of salt water intrusion in coastal reservoirs. Salt water intrusion along coastlines is highly influenced by geological and petrophysical structures. In particular, heterogeneities and anisotropy in porous media (karsts, vugs…) control fluid flow and dispersion. A new experimental site has been developed in the South East of Mallorca Island (Spain) in the context of the ALIANCE EC project (2002-2005). This project aimed at developing a strategy for the quantitative analysis and description of fluid flow and salt transport in coastal carbonate aquifers. The site drilled the Miocene carbonate reef platform at Ses Sitjoles, 6 km inland, near the city of Campos. Sea water is found there at 60 to 80 m depth. The geological structure present multi-scale heterogeneities, often bound to either lateral variations of geological facies, or dissolution patterns. The Campos site provides a unique laboratory to study the heterogeneities of carbonate rocks with a saltwater intrusion and develop new borehole investigation methods in this context. The present study focuses on borehole geophysical measurements and images, and core scans. New image analysis methods have been developed to better characterize the presence of heterogeneities in terms of grain-size distribution, formation factor changes and porosity. Cores scans from RX tomography can lead to the extraction of petrophysical parameters from 3D images. For this, the AVIZO software was used here to represent the micro-porosity and vuggy porosity structure. Beyond core analyses, the optical and acoustic borehole wall images provide a direct look at meso-scale porosity beyond cm-scale heterogeneities, such as karstic channels and megapores. The reefal complex is dominated by moldic secondary porosity, which in the upper part of the boreholes. These heterogeneities are characterized by large and elongated molds mainly detected by the acoustic images. In slope, corresponding to the lower part of the structure, moldic porosity is characterized by small and round shaped molds. Vuggy porosity varies mainly from 5 to 40% along 100 m deep boreholes. But, in the slope part, the porosity is about 0% although it can reach 90% in karstic area. In all, the distribution of pore types is strongly controlled by that of lithofacies and water paleo-levels, leading to extensive cementation processes with the resulting occlusion of pore spaces. The combined analysis of porosity with complementary methods in terms of spacial resolution leads to the quantitative determination and description of microstructural heterogeneities in carbonate porous media. It is a key to model the reservoir mesoscale structure and fluid flows within it.

  5. Cigeo, the French Geological Repository Project - 13022

    SciTech Connect

    Labalette, Thibaud; Harman, Alain; Dupuis, Marie-Claude; Ouzounian, Gerald

    2013-07-01

    The Cigeo industrial-scale geological disposal centre is designed for the disposal of the most highly-radioactive French waste. It will be built in an argillite formation of the Callovo-Oxfordian dating back 160 million years. The Cigeo project is located near the Bure village in the Paris Basin. The argillite formation was studied since 1974, and from the Meuse/Haute-Marne underground research laboratory since end of 1999. Most of the waste to be disposed of in the Cigeo repository comes from nuclear power plants and from reprocessing of their spent fuel. (authors)

  6. The geology of Ganymede

    NASA Technical Reports Server (NTRS)

    Shoemaker, E. M.; Lucchitta, B. K.; Wilhelms, D. E.; Plescia, J. B.; Squyres, S. W.

    1982-01-01

    A broad outline of the geologic history of Ganymede is presented, obtained from a first attempt to map the geology on a global scale and to interpret the characteristics of the observed geologic units. Features of the ancient cratered terrain such as craters and palimpsests, furrows and troughs, are discussed. The grooved terrain is described, including its sulci and cells, and the age relation of these units is considered along with the structure and origin of this terrain. The Gilgamesh Basin and Western Equatorial Basin in the post grooved terrain are treated, as are the bright and dark ray craters and the regolith. The development of all these regions and features is discussed in context. For the regolith, this includes the effect of water migration, sputtering, and thermal annealing. The histories of the ancient cratered terrain, the grooved terrain, and the post grooved terrain are presented.

  7. Geology of Io

    NASA Technical Reports Server (NTRS)

    Greeley, R.; Craddock, R. A.; Crown, D. A.; Leshin, L. A.; Schaber, G. G.

    1987-01-01

    Geologic mapping of the Jovian satellite Io has been completed at 1:15,000,000 scale for an area lying between +40 and -90 deg latitude and 230 and 45 deg longitude, which includes portions of the Ruwa Patera quadrangle (Ji2) and the Lerna Region (Ji4) and the westernmost section of the Colchis Region (Ji3). Image resolution in the mapped area is commonly 0.5 to 2 km/pxl. High resolution areas (less than .5 km/pxl) are located near the south pole (Lerna Region) and in eastern Ruwa Patera quadrangle. Geologic maps for the Ruwa Patera quadrangle (Ji2) and the Lerna Region (Ji4) have been produced at 1:5,000,000 scale. The present effort reexamines the previously mapped areas and synthesizes the geology of Io on a global scale.

  8. Geological fakes and frauds

    NASA Astrophysics Data System (ADS)

    Ruffell, Alastair; Majury, Niall; Brooks, William E.

    2012-02-01

    Some geological fakes and frauds are carried out solely for financial gain (mining fraud), whereas others maybe have increasing aesthetic appeal (faked fossils) or academic advancement (fabricated data) as their motive. All types of geological fake or fraud can be ingenious and sophisticated, as demonstrated in this article. Fake gems, faked fossils and mining fraud are common examples where monetary profit is to blame: nonetheless these may impact both scientific theory and the reputation of geologists and Earth scientists. The substitution or fabrication of both physical and intellectual data also occurs for no direct financial gain, such as career advancement or establishment of belief (e.g. evolution vs. creationism). Knowledge of such fakes and frauds may assist in spotting undetected geological crimes: application of geoforensic techniques helps the scientific community to detect such activity, which ultimately undermines scientific integrity.

  9. Geologic map of Mars

    USGS Publications Warehouse

    Tanaka, Kenneth L.; Skinner, James A.; Dohm, James M.; Irwin, Rossman P., III; Kolb, Eric J.; Fortezzo, Corey M.; Platz, Thomas; Michael, Gregory G.; Hare, Trent M.

    2014-01-01

    This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and interpretation in support of geologic mapping. In particular, the precise topographic mapping now available has enabled consistent morphologic portrayal of the surface for global mapping (whereas previously used visual-range image bases were less effective, because they combined morphologic and albedo information and, locally, atmospheric haze). Also, thermal infrared image bases used for this map tended to be less affected by atmospheric haze and thus are reliable for analysis of surface morphology and texture at even higher resolution than the topographic products.

  10. Geologic and Mineral Resource Map of Afghanistan

    USGS Publications Warehouse

    Doebrich, Jeff L.; Wahl, Ronald R.; With Contributions by Ludington, Stephen D.; Chirico, Peter G.; Wandrey, Craig J.; Bohannon, Robert G.; Orris, Greta J.; Bliss, James D.; Wasy, Abdul; Younusi, Mohammad O.

    2006-01-01

    Data Summary The geologic and mineral resource information shown on this map is derived from digitization of the original data from Abdullah and Chmyriov (1977) and Abdullah and others (1977). The U.S. Geological Survey (USGS) has made no attempt to modify original geologic map-unit boundaries and faults as presented in Abdullah and Chmyriov (1977); however, modifications to map-unit symbology, and minor modifications to map-unit descriptions, have been made to clarify lithostratigraphy and to modernize terminology. Labeling of map units has not been attempted where they are small or narrow, in order to maintain legibility and to preserve the map's utility in illustrating regional geologic and structural relations. Users are encouraged to refer to the series of USGS/AGS (Afghan Geological Survey) 1:250,000-scale geologic quadrangle maps of Afghanistan that are being released concurrently as open-file reports. The classification of mineral deposit types is based on the authors' interpretation of existing descriptive information (Abdullah and others, 1977; Bowersox and Chamberlin, 1995; Orris and Bliss, 2002) and on limited field investigations by the authors. Deposit-type nomenclature used for nonfuel minerals is modified from published USGS deposit-model classifications, as compiled in Stoeser and Heran (2000). New petroleum localities are based on research of archival data by the authors. The shaded-relief base is derived from Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) data having 85-meter resolution. Gaps in the original SRTM DEM dataset were filled with data digitized from contours on 1:200,000-scale Soviet General Staff Sheets (1978-1997). The marginal extent of geologic units corresponds to the position of the international boundary as defined by Abdullah and Chmyriov (1977), and the international boundary as shown on this map was acquired from the Afghanistan Information Management Service (AIMS) Web site (http://www.aims.org.af) in September 2005. Non-coincidence of these boundaries is due to differences in the respective data sources and to inexact registration of the geologic data to the DEM base. Province boundaries, province capital locations, and political names were also acquired from the AIMS Web site in September 2005. The AIMS data were originally derived from maps produced by the Afghanistan Geodesy and Cartography Head Office (AGCHO). Version 2 differs from Version 1 in that (1) map units are colored according to the color scheme of the Commission for the Geological Map of the World (CGMW) (http://www.ccgm.org), (2) the minerals database has been updated, and (3) all data presented on the map are also available in GIS format.

  11. Heterogeneous voter models

    NASA Astrophysics Data System (ADS)

    Masuda, Naoki; Gibert, N.; Redner, S.

    2010-07-01

    We introduce the heterogeneous voter model (HVM), in which each agent has its own intrinsic rate to change state, reflective of the heterogeneity of real people, and the partisan voter model (PVM), in which each agent has an innate and fixed preference for one of two possible opinion states. For the HVM, the time until consensus is reached is much longer than in the classic voter model. For the PVM in the mean-field limit, a population evolves to a preference-based state, where each agent tends to be aligned with its internal preference. For finite populations, discrete fluctuations ultimately lead to consensus being reached in a time that scales exponentially with population size.

  12. The facts on file. Dictionary of geology and geophysics

    SciTech Connect

    Lapidus, D.F.; Coates, D.R.

    1987-01-01

    This reference to the basic vocabulary of geology and geophysics has more than 3,000 clear and concise entries defining the entire range of geological phenomena. This book covers such areas as types of rocks and rock formations, deformation processes such as erosion and plate tectonics, volcanoes, glaciers and their effects on topography, geodesy and survey methods, earthquakes and seismology, fuels and mineral deposits.

  13. -PTOLEMY II -HETEROGENEOUS

    E-print Network

    California at Berkeley, University of

    -PTOLEMY II - HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA John Davis, II Ron Galicia Mudit University of California at Berkeley http://ptolemy.eecs.berkeley.edu Document Version 0.1.1 February 12.2.8. Timed CSP and Timed PN 1-5 1.3.Choosing Models of Computation 1-6 1.4.Visual Syntaxes 1-6 1.5.Ptolemy II

  14. PTOLEMY II HETEROGENEOUS

    E-print Network

    California at Berkeley, University of

    ­PTOLEMY II ­ HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA John Davis, II Ron Galicia Mudit University of California at Berkeley http://ptolemy.eecs.berkeley.edu Document Version 0.1.1 February 12 Syntaxes 1­6 1.5. Ptolemy II 1­7 1.5.1. Package Structure 1­7 1.5.2. Overview of Key Classes 1­9 1

  15. Planetary geological processes

    NASA Astrophysics Data System (ADS)

    Lopes, Rosaly M. C.; Solomonidou, Anezina

    2014-11-01

    In this introduction to planetary geology, we review the major geologic processes affecting the solid bodies of the solar system, namely volcanism, tectonism, impact cratering, and erosion. We illustrate the interplay of these processes in different worlds, briefly reviewing how they affect the surfaces of the Earth's Moon, Mercury, Venus and Mars, then focusing on two very different worlds: Jupiter's moon Io, the most volcanically active object in the solar system, and Saturn's moon Titan, where the interaction between a dense atmosphere and the surface make for remarkably earth-like landscapes despite the great differences in surface temperature and composition.

  16. The Geology of Earthquakes

    NASA Astrophysics Data System (ADS)

    Wallace, Robert E.

    The Geology of Earthquakes is a major contribution that brings together under one cover the many and complex elements of geology that are fundamental to earthquakes and seismology. Here are described and analyzed the basic causes of earthquakes, the resulting effects of earthquakes and faulting on the surface of the Earth, techniques of analyzing these effects, and engineering and public policy considerations for earthquake hazard mitigation. The three authors have played major roles in developing the fundamentals in both scientific and policy matters; thus they speak with an authority that few others could.

  17. Heterogeneity in Melanoma.

    PubMed

    Shannan, Batool; Perego, Michela; Somasundaram, Rajasekharan; Herlyn, Meenhard

    2016-01-01

    Melanoma is among the most aggressive and therapy-resistant human cancers. While great strides in therapy have generated enthusiasm, many challenges remain. Heterogeneity is the most pressing issue for all types of therapy. This chapter summarizes the clinical classification of melanoma, of which the research community now adds additional layers of classifications for better diagnosis and prediction of therapy response. As the search for new biomarkers increases, we expect that biomarker analyses will be essential for all clinical trials to better select patient populations for optimal therapy. While individualized therapy that is based on extensive biomarker analyses is an option, we expect in the future genetic and biologic biomarkers will allow grouping of melanomas in such a way that we can predict therapy outcome. At this time, tumor heterogeneity continues to be the major challenge leading inevitably to relapse. To address heterogeneity therapeutically, we need to develop complex therapies that eliminate the bulk of the tumor and, at the same time, the critical subpopulations. PMID:26601857

  18. Heterogeneities in granular dynamics.

    PubMed

    Mehta, A; Barker, G C; Luck, J M

    2008-06-17

    The absence of Brownian motion in granular media is a source of much complexity, including the prevalence of heterogeneity, whether static or dynamic, within a given system. Such strong heterogeneities can exist as a function of depth in a box of grains; this is the system we study here. First, we present results from three-dimensional, cooperative and stochastic Monte Carlo shaking simulations of spheres on heterogeneous density fluctuations. Next, we juxtapose these with results obtained from a theoretical model of a column of grains under gravity; frustration via competing local fields is included in our model, whereas the effect of gravity is to slow down the dynamics of successively deeper layers. The combined conclusions suggest that the dynamics of a real granular column can be divided into different phases-ballistic, logarithmic, activated, and glassy-as a function of depth. The nature of the ground states and their retrieval (under zero-temperature dynamics) is analyzed; the glassy phase shows clear evidence of its intrinsic ("crystalline") states, which lie below a band of approximately degenerate ground states. In the other three phases, by contrast, the system jams into a state chosen randomly from this upper band of metastable states. PMID:18541918

  19. Geologic mapping of tunnels using photogrammetry: Camera and target positioning

    NASA Astrophysics Data System (ADS)

    Coe, J. A.; Dueholm, K. S.

    A photogrammetric method has been developed by the U.S. Geological Survey and the U.S. Bureau of Reclamation for the use in geologic mapping of tunnels (drifts). The method requires photographing the tunnel walls and roof with a calibrated small-format camera to obtain stereo pairs of photos which are then oriented in an analytical stereo plotter for measurement of geologic features. The method was tested in G-tunnel at Rainier Mesa on the Nevada Test Site. Calculations necessary to determine camera and target positions and problems encountered during testing were used to develop a set of generic formulas that can be applied to any tunnel.

  20. Outcrop descriptions and fossils from the Upper Cretaceous Frontier Formation, Wind River Basin and adjacent areas, Wyoming: Chapter 11 in Petroleum systems and geologic assessment of oil and gas resources in the Wind River Basin Province, Wyoming

    USGS Publications Warehouse

    Merewether, E.A.; Cobban, W.A.

    2007-01-01

    The index maps used to show locations of outcrop sections and fossil collections are from scanned versions of U.S. Geological Survey topographic maps of various scales and were obtained from TerraServer®. The portion of each map used depended on the areal distribution of the localities involved. The named quadrangles used for locality descriptions, however, all refer to 7½-minute, 1:24,000-scale quadrangles (for example, “Alcova”). The aerial photographs also are from TerraServer®; http://www.terraserver.com/.

  1. Knob heights within circum-Caloris geologic units on Mercury: Interpretations of the geologic history of the region

    NASA Astrophysics Data System (ADS)

    Ackiss, S. E.; Buczkowski, D. L.; Ernst, C. M.; McBeck, J. A.; Seelos, K. D.

    2015-11-01

    The circum-Caloris geologic units show morphology consistent with ejecta-derived formation, however crater counts suggest the units formed after the basin. To determine if the surrounding units are directly related to basin formation or products of later volcanic resurfacing events, we measured the heights and densities of knobs in 22 study regions to the east of the Caloris basin in three geologic units circumferential to the basin: the Odin Formation, the Van Eyck Formation, and the Smooth Plains Formation. In these study regions the size and concentration of ejecta blocks generally decrease away from the crater rim. The morphology that superposes the knobs and the distribution of knob heights within each study region suggests that the knobs were deposited as ejecta and later embayed by one or multiple volcanic events. The distribution of knob height and concentration indicates that the knobs within the circum-Caloris units are related to the formation of the basin.

  2. Geological research for public outreach and education in Lithuania

    NASA Astrophysics Data System (ADS)

    Skridlaite, Grazina; Guobyte, Rimante

    2013-04-01

    Successful IYPE activities and implementation of Geoheritage day in Lithuania increased public awareness in geology. A series of projects introducing geology to the general public and youth, supported by EU funds and local communities, were initiated. Researchers from the scientific and applied geology institutions of Lithuania participated in these projects and provided with the geological data. In one case, the Lithuanian Survey of Protected Areas supported the installation of a series of geological exhibitions in several regional and national parks. An animation demonstrating glacial processes was chosen for most of these because the Lithuanian surface is largely covered with sedimentary deposits of the Nemunas (Weichselian) glaciation. Researchers from the Lithuanian Geological Survey used the mapping results to demonstrate real glacial processes for every chosen area. In another case, 3D models showing underground structures of different localities were based on detailed geological maps and profiles obtained for that area. In case of the Sartai regional park, the results of previous geological research projects provided the possibility to create a movie depicting the ca. 2 Ga geological evolution of the region. The movie starts with the accretion of volcanic island arcs on the earlier continental margin at ca. 2 Ga and deciphers later Precambrian tectonic and magmatic events. The reconstruction is based on numerous scientific articles and interpretation of geophysical data. Later Paleozoic activities and following erosion sculptured the surface which was covered with several ice sheets in Quaternary. For educational purpose, a collection of minerals and rocks at the Forestry Institute was used to create an exhibition called "Cycle of geological processes". Forestry scientists and their students are able to study the interactions of geodiversity and biodiversity and to understand ancient and modern geological processes leading to a soil formation. An aging exposition at the Museum of Erratic Boulders in NW Lithuania is being rearranged for educational purposes, to show the major rock types and their origins more clearly. A new exhibition is supplemented with computer portals presenting geological processes, geological quizzes, animations etc. Magmatism, metamorphism, sedimentation and other geological processes are demonstrated using erratic boulders brought by glaciers from Scandinavia and northern Russia. A part of the exhibition is devoted to glaciation processes and arrival of ice sheets to Lithuania. Visitors are able to examine large erratic boulder groups in a surrounding park and to enjoy beautiful environment. The exhibition also demonstrates mineral resources of Lithuania, different fossils and stones from a human body. In all cases it was recognised that a lack of geological information limits the use of geology for public outreach. Ongoing scientific research is essential in many places as well as a mediator's job for interpreting the results of highly specialised research results and to adapt them for public consumption.

  3. Nighttime chemical evolution of aerosol and trace gases in a power plant plume: Implications for secondary organic nitrate and organosulfate aerosol formation, NO3 radical chemistry, and N2O5 heterogeneous hydrolysis

    SciTech Connect

    Zaveri, R.A.; Kleinman, L.; Berkowitz, C. M.; Brechtel, F. J.; Gilles, M. K.; Hubbe, J. M.; Jayne, J. T.; Laskin, A.; Madronich, S.; Onasch, T. B.; Pekour, M. S.; Springston, S. R.; Thornton, J. A.; Tivanski, A. V.; Worsnop, D. R.

    2010-06-01

    Nighttime chemical evolution of aerosol and trace gases in a coal-fired power plant plume was monitored with the Department of Energy Grumman Gulfstream-1 aircraft during the 2002 New England Air Quality Study field campaign. Quasi-Lagrangian sampling in the plume at increasing downwind distances and processing times was guided by a constant-volume balloon that was released near the power plant at sunset. While no evidence of fly ash particles was found, concentrations of particulate organics, sulfate, and nitrate were higher in the plume than in the background air. The enhanced sulfate concentrations were attributed to direct emissions of gaseous H{sub 2}SO{sub 4}, some of which had formed new particles as evidenced by enhanced concentrations of nucleation-mode particles in the plume. The aerosol species were internally mixed and the particles were acidic, suggesting that particulate nitrate was in the form of organic nitrate. The enhanced particulate organic and nitrate masses in the plume were inferred as secondary organic aerosol, which was possibly formed from NO{sub 3} radical-initiated oxidation of isoprene and other trace organic gases in the presence of acidic sulfate particles. Microspectroscopic analysis of particle samples suggested that some sulfate was in the form of organosulfates. Microspectroscopy also revealed the presence of sp{sup 2} hybridized C = C bonds, which decreased with increasing processing time in the plume, possibly because of heterogeneous chemistry on particulate organics. Constrained plume modeling analysis of the aircraft and tetroon observations showed that heterogeneous hydrolysis of N{sub 2}O{sub 5} was negligibly slow. These results have significant implications for several issues related to the impacts of power plant emissions on air quality and climate.

  4. Nighttime chemical evolution of aerosol and trace gases in a power plant plume: Implications for secondary organic nitrate and organosulfate aerosol formation, NO3 radical chemistry, and N2O5 heterogeneous hydrolysis

    NASA Astrophysics Data System (ADS)

    Zaveri, Rahul A.; Berkowitz, Carl M.; Brechtel, Fred J.; Gilles, Mary K.; Hubbe, John M.; Jayne, John T.; Kleinman, Lawrence I.; Laskin, Alexander; Madronich, Sasha; Onasch, Timothy B.; Pekour, Mikhail S.; Springston, Stephen R.; Thornton, Joel A.; Tivanski, Alexei V.; Worsnop, Douglas R.

    2010-06-01

    Nighttime chemical evolution of aerosol and trace gases in a coal-fired power plant plume was monitored with the Department of Energy Grumman Gulfstream-1 aircraft during the 2002 New England Air Quality Study field campaign. Quasi-Lagrangian sampling in the plume at increasing downwind distances and processing times was guided by a constant-volume balloon that was released near the power plant at sunset. While no evidence of fly ash particles was found, concentrations of particulate organics, sulfate, and nitrate were higher in the plume than in the background air. The enhanced sulfate concentrations were attributed to direct emissions of gaseous H2SO4, some of which had formed new particles as evidenced by enhanced concentrations of nucleation-mode particles in the plume. The aerosol species were internally mixed and the particles were acidic, suggesting that particulate nitrate was in the form of organic nitrate. The enhanced particulate organic and nitrate masses in the plume were inferred as secondary organic aerosol, which was possibly formed from NO3 radical-initiated oxidation of isoprene and other trace organic gases in the presence of acidic sulfate particles. Microspectroscopic analysis of particle samples suggested that some sulfate was in the form of organosulfates. Microspectroscopy also revealed the presence of sp2 hybridized C = C bonds, which decreased with increasing processing time in the plume, possibly because of heterogeneous chemistry on particulate organics. Constrained plume modeling analysis of the aircraft and tetroon observations showed that heterogeneous hydrolysis of N2O5 was negligibly slow. These results have significant implications for several issues related to the impacts of power plant emissions on air quality and climate.

  5. Characterization of oil and gas reservoir heterogeneity

    SciTech Connect

    Tyler, N.; Barton, M.D.; Bebout, D.G.; Fisher, R.S.; Grigsby, J.D.; Guevara, E.; Holtz, M.; Kerans, C.; Nance, H.S.; Levey, R.A.

    1992-10-01

    Research described In this report addresses the internal architecture of two specific reservoir types: restricted-platform carbonates and fluvial-deltaic sandstones. Together, these two reservoir types contain more than two-thirds of the unrecovered mobile oil remaining ill Texas. The approach followed in this study was to develop a strong understanding of the styles of heterogeneity of these reservoir types based on a detailed outcrop description and a translation of these findings into optimized recovery strategies in select subsurface analogs. Research targeted Grayburg Formation restricted-platform carbonate outcrops along the Algerita Escarpment and In Stone Canyon In southeastern New Mexico and Ferron deltaic sandstones in central Utah as analogs for the North Foster (Grayburg) and Lake Creek (Wilcox) units, respectively. In both settings, sequence-stratigraphic style profoundly influenced between-well architectural fabric and permeability structure. It is concluded that reservoirs of different depositional origins can therefore be categorized Into a heterogeneity matrix'' based on varying intensity of vertical and lateral heterogeneity. The utility of the matrix is that it allows prediction of the nature and location of remaining mobile oil. Highly stratified reservoirs such as the Grayburg, for example, will contain a large proportion of vertically bypassed oil; thus, an appropriate recovery strategy will be waterflood optimization and profile modification. Laterally heterogeneous reservoirs such as deltaic distributary systems would benefit from targeted infill drilling (possibly with horizontal wells) and improved areal sweep efficiency. Potential for advanced recovery of remaining mobile oil through heterogeneity-based advanced secondary recovery strategies In Texas is projected to be an Incremental 16 Bbbl. In the Lower 48 States this target may be as much as 45 Bbbl at low to moderate oil prices over the near- to mid-term.

  6. Geological and Inorganic Materials.

    ERIC Educational Resources Information Center

    Jackson, L. L.; And Others

    1989-01-01

    Presents a review focusing on techniques and their application to the analysis of geological and inorganic materials that offer significant changes to research and routine work. Covers geostandards, spectroscopy, plasmas, microbeam techniques, synchrotron X-ray methods, nuclear activation methods, chromatography, and electroanalytical methods.…

  7. Geology: The Active Earth.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1987-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Geology: The Active Earth." Contents are organized into the following…

  8. Geological impacts on nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter reviews the nutritional roles of mineral elements, as part of a volume on health implications of geology. The chapter addresses the absorption and post-absorptive utilization of the nutritionally essential minerals, including their physiological functions and quantitative requirements....

  9. Appendix E: Geology

    SciTech Connect

    Reidel, Steve; Chamness, Mickie A.

    2008-01-17

    This appendix provides a detailed description of geology under the Central Plateau of the Hanford Site, emphasizing the areas around tank farms. It is to be published by client CH2M HILL Hanford Group, Inc., as part of a larger, multi-contractor technical report.

  10. Dinosaur Paleobiology Geology 331

    E-print Network

    Kammer, Thomas

    Dinosaur Paleobiology Geology 331 Paleontology #12;Dinosaurs are popular with the public #12;Jack Horner, Montana State Univ. #12;Field Work in Montana #12;A dinosaur "drumstick" in its field jacket. #12;Abundant vascular canals in dinosaur bone support the warm-