Nitrate reduction in geologically heterogeneous catchments — A framework for assessing the scale of predictive capability of hydrological models

International Nuclear Information System (INIS)

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

2014-01-01

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 2 m, 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

Nitrate reduction in geologically heterogeneous catchments — A framework for assessing the scale of predictive capability of hydrological models

Energy Technology Data Exchange (ETDEWEB)

Refsgaard, Jens Christian, E-mail: jcr@geus.dk [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Auken, Esben [Department of Earth Sciences, Aarhus University (Denmark); Bamberg, Charlotte A. [City of Aarhus (Denmark); Christensen, Britt S.B. [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Clausen, Thomas [DHI, Hørsholm (Denmark); Dalgaard, Esben [Department of Earth Sciences, Aarhus University (Denmark); Effersø, Flemming [SkyTEM Aps, Beder (Denmark); Ernstsen, Vibeke [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Gertz, Flemming [Knowledge Center for Agriculture, Skejby (Denmark); Hansen, Anne Lausten [Department of Geosciences and Natural Resource Management, University of Copenhagen (Denmark); He, Xin [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Jacobsen, Brian H. [Department of Food and Resource Economics, University of Copenhagen (Denmark); Jensen, Karsten Høgh [Department of Geosciences and Natural Resource Management, University of Copenhagen (Denmark); Jørgensen, Flemming; Jørgensen, Lisbeth Flindt [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Koch, Julian [Department of Geosciences and Natural Resource Management, University of Copenhagen (Denmark); Nilsson, Bertel [Geological Survey of Denmark and Greenland (GEUS) (Denmark); Petersen, Christian [City of Odder (Denmark); De Schepper, Guillaume [Université Laval, Québec (Canada); Schamper, Cyril [Department of Earth Sciences, Aarhus University (Denmark); and others

2014-01-01

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 2 m, 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

Heterogeneity-enhanced gas phase formation in shallow aquifers during leakage of CO2-saturated water from geologic sequestration sites

Science.gov (United States)

Plampin, Michael R.; Lassen, Rune N.; Sakaki, Toshihiro; Porter, Mark L.; Pawar, Rajesh J.; Jensen, Karsten H.; Illangasekare, Tissa H.

2014-12-01

A primary concern for geologic carbon storage is the potential for leakage of stored carbon dioxide (CO2) into the shallow subsurface where it could degrade the quality of groundwater and surface water. In order to predict and mitigate the potentially negative impacts of CO2 leakage, it is important to understand the physical processes that CO2 will undergo as it moves through naturally heterogeneous porous media formations. Previous studies have shown that heterogeneity can enhance the evolution of gas phase CO2 in some cases, but the conditions under which this occurs have not yet been quantitatively defined, nor tested through laboratory experiments. This study quantitatively investigates the effects of geologic heterogeneity on the process of gas phase CO2 evolution in shallow aquifers through an extensive set of experiments conducted in a column that was packed with layers of various test sands. Soil moisture sensors were utilized to observe the formation of gas phase near the porous media interfaces. Results indicate that the conditions under which heterogeneity controls gas phase evolution can be successfully predicted through analysis of simple parameters, including the dissolved CO2 concentration in the flowing water, the distance between the heterogeneity and the leakage location, and some fundamental properties of the porous media. Results also show that interfaces where a less permeable material overlies a more permeable material affect gas phase evolution more significantly than interfaces with the opposite layering.

Heterogeneity-enhanced gas phase formation in shallow aquifers during leakage of CO2-saturated water from geologic sequestration sites

DEFF Research Database (Denmark)

Plampin, Michael R.; Lassen, Rune Nørbæk; Sakaki, Toshihiro

2014-01-01

sands. Soil moisture sensors were utilized to observe the formation of gas phase near the porous media interfaces. Results indicate that the conditions under which heterogeneity controls gas phase evolution can be successfully predicted through analysis of simple parameters, including the dissolved CO2......, it is important to understand the physical processes that CO2 will undergo as it moves through naturally heterogeneous porous media formations. Previous studies have shown that heterogeneity can enhance the evolution of gas phase CO2 in some cases, but the conditions under which this occurs have not yet been...... quantitatively defined, nor tested through laboratory experiments. This study quantitatively investigates the effects of geologic heterogeneity on the process of gas phase CO2 evolution in shallow aquifers through an extensive set of experiments conducted in a column that was packed with layers of various test...

The geological basis and the representation of spatial variability in sedimentary heterogeneous media

International Nuclear Information System (INIS)

Cliffe, K.A.; Franklin, D.J.; Jones, P.I.R.; Macleod, E.J.; Porter, J.D.

1998-01-01

The impact of different conceptual models was investigated of the heterogeneity of the Sherwood Sandstone Group (SSG) at Sellafield on calculations of flow and transport. Detailed models of the heterogeneity of the Undifferentiated St Bees Sandstone (USBS) of the SSG were produced. The models took into account directly the geological structures at the facies level. The software package STORM (STOchastic Reservoir Modelling), was used to construct the models. The data required by the model are those that characterise the geometry of the channel bodies and the properties of the various sub-facies within the channels. It was found that for the case in which all of the variability was within channels, the larger scale permeabilities did not exhibit any significant correlation structure. The up-scaled effective permeabilities also exhibited correlation lengths that were comparable with the channel dimensions. Flow and transport calculations were also performed on 90 realizations of a detailed facies scale three-dimensional representation of a larger block of the USBS. The results are broadly consistent with the analytical results for transport through a random permeability field. (R.P.)

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

Science.gov (United States)

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

Geological investigations for geological model of deep underground geoenvironment at the Mizunami Underground Research Laboratory (MIU)

International Nuclear Information System (INIS)

Tsuruta, Tadahiko; Tagami, Masahiko; Amano, Kenji; Matsuoka, Toshiyuki; Kurihara, Arata; Yamada, Yasuhiro; Koike, Katsuaki

2013-01-01

Japan Atomic Energy Agency (JAEA) is performing a geoscientific research project, the Mizunami Underground Research Laboratory (MIU) project, in order to establish scientific and technological basis for geological disposal of high-level radioactive wastes. The MIU is located in crystalline rock environment, in Mizunami City, central Japan. Field investigations include geological mapping, reflection seismic surveys, several borehole investigations and geological investigations in the research galleries to identify the distribution and heterogeneity of fractures and faults that are potential major flowpaths for groundwater. The results of these field investigations are synthesized and compiled for the purpose of geological modeling. The field investigations indicate that the Main Shaft at the MIU intersected low permeability NNW oriented faults. A high permeability fracture zone in the granite, a significant water inflow point, was observed in the Ventilation Shaft. Development of the geological model focusing 3D spatial relationships at different scales and evolution of the geoenvironment are underway. This paper describes geological investigations applied in the MIU project, focusing on the evaluation of their effectiveness to understand for deep underground geoenvironment. (author)

Study on evaluation method for heterogeneous sedimentary rocks based on forward model

International Nuclear Information System (INIS)

Masui, Yasuhiro; Kawada, Koji; Katoh, Arata; Tsuji, Takashi; Suwabe, Mizue

2004-02-01

It is very important to estimate the facies distribution of heterogeneous sedimentary rocks for geological disposal of high level radioactive waste. The heterogeneousness of sedimentary rocks is due to variable distribution of grain size and mineral composition. The objective of this study is to establish the evaluation method for heterogeneous sedimentary rocks based on forward model. This study consisted of geological study for Horonobe area and the development of soft wear for sedimentary model. Geological study was composed of following items. 1. The sedimentary system for Koetoi and Wakkanai formations in Horonobe area was compiled based on papers. 2. The cores of HDB-1 were observed mainly from sedimentological view. 3. The facies and compaction property of argillaceous rocks were studied based on physical logs and core analysis data of wells. 4. The structure maps, isochrone maps, isopach maps and restored geological sections were made. The soft wear for sedimentary model to show sedimentary system on a basin scale was developed. This soft wear estimates the facies distribution and hydraulic conductivity of sedimentary rocks on three dimensions scale by numerical simulation. (author)

Geologically based model of heterogeneous hydraulic conductivity in an alluvial setting

Science.gov (United States)

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

Assessing correlations between geological hazards and health outcomes: Addressing complexity in medical geology.

Science.gov (United States)

Wardrop, Nicola Ann; Le Blond, Jennifer Susan

2015-11-01

The field of medical geology addresses the relationships between exposure to specific geological characteristics and the development of a range of health problems: for example, long-term exposure to arsenic in drinking water can result in the development of skin conditions and cancers. While these relationships are well characterised for some examples, in others there is a lack of understanding of the specific geological component(s) triggering disease onset, necessitating further research. This paper aims to highlight several important complexities in geological exposures and the development of related diseases that can create difficulties in the linkage of exposure and health outcome data. Several suggested approaches to deal with these complexities are also suggested. Long-term exposure and lengthy latent periods are common characteristics of many diseases related to geological hazards. In combination with long- or short-distance migrations over an individual's life, daily or weekly movement patterns and small-scale spatial heterogeneity in geological characteristics, it becomes problematic to appropriately assign exposure measurements to individuals. The inclusion of supplementary methods, such as questionnaires, movement diaries or Global Positioning System (GPS) trackers can support medical geology studies by providing evidence for the most appropriate exposure measurement locations. The complex and lengthy exposure-response pathways involved, small-distance spatial heterogeneity in environmental components and a range of other issues mean that interdisciplinary approaches to medical geology studies are necessary to provide robust evidence. Copyright © 2015. Published by Elsevier Ltd.

High resolution reservoir geological modelling using outcrop information

Energy Technology Data Exchange (ETDEWEB)

Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

1997-08-01

This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

MUSEUM GEOLOGI DAN PRASEJARAH DI MAKASSAR DENGAN PENDEKATAN ARSITEKTUR HIGH TECH

Directory of Open Access Journals (Sweden)

Saefullah Saefullah

2015-12-01

Full Text Available Abstrak—Indonesia kaya akan sumber daya geologi yang terdiri dari batuan, mineral dan bahan tambang. Berbicara mengenai geologi sangat erat kaitannya dengan zaman prasejarah.karena belum ditemukannya bukti-bukti tertulis dari zaman prasejarah tersebut, keterangan mengenai zaman ini diperoleh melalui bidang-bidang seperti paleontologi, astronomi, biologi, geologi, antropologi, dan arkeologi pentingnya melestarikan dan menjaga peninggalan-peninggalan prasejarah. Sehingga akan menumbuhkan rasa tanggungjawab terhadapnya. Hal ini sejalan dengan tugas Direktorat Jendral Kebudayaan Kementrian Pendidikan dan Kebudyaaan Indonesia dalam laporan kinerjanya .yang mengemukakan bahwa sisa-sisa peninggalan sejarah penting dipelihara sebagai pelajaran hidup bagi generasi berikutnya.Tujuan penelitian menyusun suatu landasan konseptual desain perancangan Museum Geologi dan prasejarah dengan pendekatan arsitektur high-tech, menerapkan system Double fasade, Ligth Pipe dan system fotovoltaic pada bangunan, mengaplikasikan intelegent system pada utilitas pada bangunan.Hasil Laporan ini adalah mendesain bangunan museum geologi dan prasejarah di Makassar dengan pendekatan arsitektur high-tech. Kata Kunci :Museum geologi, prasejarah, high-tech Abstract-Indonesia is rich geological resources consisting of rocks, minerals and minerals. Talking about the geology is very closely related to prehistoric times because of not finding written evidence from prehistoric times, the information concerning this age obtained through fields like paleontology, astronomy, biology, geology, anthropology, and archeology importance of preserving and maintaining prehistoric relics. So will foster a sense of responsibility to it. This is in line with the duties of the Directorate General of Culture Ministry of Education and Indonesian culture in its performance report which suggested that the remains of important historical remains preserved as a living lesson for the next generation. The

A Geospatial Information Grid Framework for Geological Survey

OpenAIRE

Wu, Liang; Xue, Lei; Li, Chaoling; Lv, Xia; Chen, Zhanlong; Guo, Mingqiang; Xie, Zhong

2015-01-01

The use of digital information in geological fields is becoming very important. Thus, informatization in geological surveys should not stagnate as a result of the level of data accumulation. The integration and sharing of distributed, multi-source, heterogeneous geological information is an open problem in geological domains. Applications and services use geological spatial data with many features, including being cross-region and cross-domain and requiring real-time updating. As a result of ...

Geology of high-level nuclear waste disposal

International Nuclear Information System (INIS)

Roxburgh, I.S.

1988-01-01

The concept of geological disposal is set out by describing the major rock types in terms of their ability to isolate high-level nuclear waste. The advantages and problems posed by particular rock formations are explored and the design and construction of geological repositories is considered, along with the methods used to estimate their safety. It gives special consideration to the use of sea-covered rock and sediment as well as the on-land situation. Throughout the book the various principles and problems inherent in geological disposal are explained and illustrated by reference to a multitude of European and North American case studies, backed up by a large number of tables, figures and an extensive bibliography

Safety of geologic disposal of high level radioactive waste

International Nuclear Information System (INIS)

Zaitsu, Tomohisa; Ishiguro, Katsuhiko; Masuda, Sumio

1992-01-01

This article introduces current concepts of geologic disposal of high level radioactive waste and its safety. High level radioactive waste is physically stabilized by solidifying it in a glass form. Characteristics of deep geologic layer are presented from the viewpoint of geologic disposal. Reconstruction of multi-barrier system receives much attention to secure the safety of geologic disposal. It is important to research performance assessment of multi-barrier system for preventing dissolution or transfer of radionuclides into the ground water. Physical and chemical modeling for the performance assessment is outlined in the following terms: (1) chemical property of deep ground water, (2) geochemical modeling of artificial barrier spatial water, (3) hydrology of deep ground water, (4) hydrology of the inside of artificial barrier, and (5) modeling of radionuclide transfer from artificial barrier. (N.K.)

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

Energy Technology Data Exchange (ETDEWEB)

Illangasekare, Tissa [Colorado School of Mines, Golden, CO (United States); Trevisan, Luca [Colorado School of Mines, Golden, CO (United States); Agartan, Elif [Colorado School of Mines, Golden, CO (United States); Mori, Hiroko [Colorado School of Mines, Golden, CO (United States); Vargas-Johnson, Javier [Colorado School of Mines, Golden, CO (United States); Gonzalez-Nicolas, Ana [Colorado School of Mines, Golden, CO (United States); Cihan, Abdullah [Colorado School of Mines, Golden, CO (United States); Birkholzer, Jens [Colorado School of Mines, Golden, CO (United States); Zhou, Quanlin [Colorado School of Mines, Golden, CO (United States)

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

Numerical Study of Critical Role of Rock Heterogeneity in Hydraulic Fracture Propagation

Energy Technology Data Exchange (ETDEWEB)

J. Zhou; H. Huang; M. Deo

2016-03-01

Log and seismic data indicate that most shale formations have strong heterogeneity. Conventional analytical and semi-analytical fracture models are not enough to simulate the complex fracture propagation in these highly heterogeneous formation. Without considering the intrinsic heterogeneity, predicted morphology of hydraulic fracture may be biased and misleading in optimizing the completion strategy. In this paper, a fully coupling fluid flow and geomechanics hydraulic fracture simulator based on dual-lattice Discrete Element Method (DEM) is used to predict the hydraulic fracture propagation in heterogeneous reservoir. The heterogeneity of rock is simulated by assigning different material force constant and critical strain to different particles and is adjusted by conditioning to the measured data and observed geological features. Based on proposed model, the effects of heterogeneity at different scale on micromechanical behavior and induced macroscopic fractures are examined. From the numerical results, the microcrack will be more inclined to form at the grain weaker interface. The conventional simulator with homogeneous assumption is not applicable for highly heterogeneous shale formation.

Use of geological mapping tools to improve the hydraulic performance of SuDS.

Science.gov (United States)

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.

Geological disposal of high-level radioactive waste and geological environment in Japan

International Nuclear Information System (INIS)

Shimizu, Kazuhiko; Seo, Toshihiro; Yshida, Hidekazu

2001-01-01

The geological environment has two main functions in terms of ensuring the safety of geological disposal of high-level radioactive waste. One relates to the fundamental long-term stability of the site and the other to the properties of the host rock formations and groundwaters which facilitate the emplacement of the engineered barrier system and act as a natural barrier. In this connection, the feasibility of selecting a geological environment in Japan which is appropriate for geological disposal was discussed, based on findings obtained from case studies and field measurements. Considering long-term stability of the site, it is important to understand the effects and spatial distributions of the natural phenomena such as fault movement, volcanic activity, uplift/denudation and climatic/sea-level changes. Fault movement and volcanic activity are relatively localized phenomena, and can be avoided by considering only areas that are sufficiently remote from existing volcanoes and major active faults for these phenomena to have a negligible probability of causing significant effects. Uplift/denudation and climatic/sea-level changes are gradual phenomena and are more ubiquitous. It is, nevertheless, possible to estimate future trends by extrapolating the past changes into the future, and then to identify areas that may not be affected significantly by such phenomena. Considering the properties of the host rocks and groundwaters, it can be understood, from the presently available data, that deep groundwater in Japan generally flows slowly and its chemistry is in a reduced state. The data also suggest that deep rock masses, where the ground temperature is acceptably low and the rock pressure is almost homogeneous, are widely located throughout Japan. Based on the examination of the geological environment in Japan, it is possible to discuss the requirements for the geological environment to be considered and the investigations to be performed during the site selection

A two-phase model of aquifer heterogeneity

International Nuclear Information System (INIS)

Moltyaner, G.L.

1994-11-01

A two-phase model of a fluid-saturated geologic medium is developed with groundwater velocity (rather than the hydraulic conductivity) as the primary model parameter. The model describes the groundwater flow, contaminant transport processes, and geologic medium structure at the local-scale of a continuum representation and relates structure to processes quantitatively. In this model, the heterogeneity of a geologic medium is characterized either in terms of the spatial variability in the bulk (local-scale) fluid density and sediment density, or in terms of variability in the local-scale porosity and effective grain diameter. The local-scale continuity equations resulting from these properties are derived for both phases. The effective grain diameter is employed to quantify the geologic structure. Velocity is employed to quantify the transport process. Since structure controls process, a high correlation is observed between the effective grain diameter and velocity. The observed correlation leads to a new formulation of Darcy's law without invoking the concept of a fictitious (Darcy's) velocity. The local-scale groundwater flow equation is developed on the basis of the new formulation. (author). 16 refs., 4 figs

Geostatistical simulation of geological architecture and uncertainty propagation in groundwater modeling

DEFF Research Database (Denmark)

He, Xiulan

parameters and model structures, which are the primary focuses of this PhD research. Parameter uncertainty was analyzed using an optimization tool (PEST: Parameter ESTimation) in combination with a random sampling method (LHS: Latin Hypercube Sampling). Model structure, namely geological architecture...... be compensated by model parameters, e.g. when hydraulic heads are considered. However, geological structure is the primary source of uncertainty with respect to simulations of groundwater age and capture zone. Operational MPS based software has been on stage for just around ten years; yet, issues regarding...... geological structures of these three sites provided appropriate conditions for testing the methods. Our study documented that MPS is an efficient approach for simulating geological heterogeneity, especially for non-stationary system. The high resolution of geophysical data such as SkyTEM is valuable both...

Radionuclide transport calculations from high-level long-lived radioactive waste disposal in deep clayey geologic formation toward adjacent aquifers

International Nuclear Information System (INIS)

Genty, A.; Le Potier, C.

2007-01-01

In the context of high-level nuclear waste repository safety calculations, the modeling of radionuclide migration is of first importance. Three dimensional radionuclide transport calculations in geological repository need to describe objects of the meter scale embedded in geologic layer formations of kilometer extension. A complete and refined spatial description would end up with at least meshes of hundreds of millions to billions elements. The resolution of this kind of problem is today not reachable with classical computers due to resources limitations. Although parallelized computation appears as potential tool to handle multi-scale calculations, to our knowledge no attempt have been yet performed. One emerging solution for repository safety calculations on very large cells meshes consists in using a domain decomposition approach linked to massive parallelized computer calculation. In this approach, the repository domain is divided in small elementary domains and transport calculation are performed independently on different processor for each elementary domain. Before to develop this possible solution, we performed some preliminary test in order to access the order of magnitude of cells needed to perform converged calculation on one elementary disposal domain and to check if Finite Volume (FV) based on Multi Point Flux Approximation (MPFA) spatial scheme or more classical Mixed Hybrid Finite Element (MHFE) spatial scheme were adapted for those calculations in highly heterogeneous porous media. Our preliminary results point out that MHFE and VF schemes applied on non-parallelepiped hexahedral cells for flow and transport calculations in highly heterogeneous media gave satisfactory results. Nevertheless further investigations and additional calculations are needed in order to exhibit the mesh discretization level needed to perform converged calculations. (authors)

Use of integrated geologic and geophysical information for characterizing the structure of fracture systems at the US/BK Site, Grimsel Laboratory, Switzerland

International Nuclear Information System (INIS)

Martel, S.J.; Peterson, J.E. Jr.

1990-05-01

Fracture systems form the primary fluid flow paths in a number of rock types, including some of those being considered for high level nuclear waste repositories. In some cases, flow along fractures must be modeled explicitly as part of a site characterization effort. Fractures commonly are concentrated in fracture zones, and even where fractures are seemingly ubiquitous, the hydrology of a site can be dominated by a few discrete fracture zones. We have implemented a site characterization methodology that combines information gained from geophysical and geologic investigations. The general philosophy is to identify and locate the major fracture zones, and then to characterize their systematics. Characterizing the systematics means establishing the essential and recurring patterns in which fractures are organized within the zones. We make a concerted effort to use information on the systematics of the fracture systems to link the site-specific geologic, borehole and geophysical information. This report illustrates how geologic and geophysical information on geologic heterogeneities can be integrated to guide the development of hydrologic models. The report focuses on fractures, a particularly common type of geologic heterogeneity. However, many aspects of the methodology we present can be applied to other geologic heterogeneities as well. 57 refs., 40 figs., 1 tab

Disposal of high level radioactive wastes in geological formations

International Nuclear Information System (INIS)

Martins, L.A.M.; Carvalho Bastos, J.P. de

1978-01-01

The disposal of high-activity radioactive wastes is the most serious problem for the nuclear industry. Among the solutions, the disposal of wastes in approriated geological formations is the most realistic and feasible. In this work the methods used for geological disposal, as well as, the criteria, programs and analysis for selecting a bite for waste disposal are presented [pt

Geological survey by high resolution electrical survey on granite areas

International Nuclear Information System (INIS)

Sugimoto, Yoshihiro; Yamada, Naoyuki

2002-03-01

As an Integral part of the geological survey in 'The study of the regions ground water flow system' that we are carrying out with Tono Geoscience Center, we proved the relation between the uncontinuation structure such as lineament in the base rock and resistivity structure (resistivity distribution), for the purpose of that confirms the efficacy of the high resolution electrical survey as geological survey, we carried out high resolution electrical survey on granite area. We obtained the following result, by the comparison of resistivity distribution with established geological survey, lineament analysis and investigative drilling. 1. The resistivity structure of this survey area is almost able to classify it into the following four range. 1) the low resistivity range of 50-800 Ωm, 2) The resistivity range like the middle of 200-2000 Ωm, 3) The high resistivity range of 2000 Ωm over, 4) The low resistivity range of depth of the survey line 400-550 section. 2. The low resistivity range of 4) that correspond with the established geological data is not admitted. 3. It was confirmed that resistivity structure almost correspond to geological structure by the comparison with the established data. 4. The small-scale low resistivity area is admitted in the point equivalent to the lineament position of established. 5. We carried out it with the simulation method about the low resistivity range of 4). As a result, it understood that it has the possibility that the narrow ratio low resistivity area is shown as the wide ratio resistivity range in the analysis section. In the survey in this time, it is conceivable that the resistivity distribution with the possibility of the unhomogeneous and uncontinuation structure of the base rock is being shown conspicuously, the efficacy of the high resolution resistivity survey as geological survey on granite was shown. (author)

HSM: Heterogeneous Subspace Mining in High Dimensional Data

DEFF Research Database (Denmark)

Müller, Emmanuel; Assent, Ira; Seidl, Thomas

2009-01-01

Heterogeneous data, i.e. data with both categorical and continuous values, is common in many databases. However, most data mining algorithms assume either continuous or categorical attributes, but not both. In high dimensional data, phenomena due to the "curse of dimensionality" pose additional...... challenges. Usually, due to locally varying relevance of attributes, patterns do not show across the full set of attributes. In this paper we propose HSM, which defines a new pattern model for heterogeneous high dimensional data. It allows data mining in arbitrary subsets of the attributes that are relevant...... for the respective patterns. Based on this model we propose an efficient algorithm, which is aware of the heterogeneity of the attributes. We extend an indexing structure for continuous attributes such that HSM indexing adapts to different attribute types. In our experiments we show that HSM efficiently mines...

Uncertainties in the geological disposal for high-level radioactive waste

International Nuclear Information System (INIS)

Liu Xiaodong; Wang Changxuan

2008-01-01

Geological disposal, referring to the disposal of high-level solid radioactive waste in a facility located underground in a stable geological formation, was considered the most favourable methods to provide long term isolation of the radionuclides in the waste from the biosphere, and was adopted by IAEA and the developed nations with nuclear facilities. Over 50 years studies have been proved the technical feasibility of geological disposal for radioactive waste. However, there are many subjective and objective uncertainties on development, operation and closure of a geological disposal facility. For providing flexibility in responding to new technical information, advances in waste management and materials technologies, and in enabling social, economic and political aspects to be addressed, it is necessary to evaluate the uncertainties for all the R and D steps of a geological disposal program. (authors)

Upscaling of permeability heterogeneities in reservoir rocks; an integrated approach

NARCIS (Netherlands)

Mikes, D.

2002-01-01

This thesis presents a hierarchical and geologically constrained deterministic approach to incorporate small-scale heterogeneities into reservoir flow simulators. We use a hierarchical structure to encompass all scales from laminae to an entire depositional system. For the geological models under

Spatial Abilities of High-School Students in the Perception of Geologic Structures.

Science.gov (United States)

Kali, Yael; Orion, Nir

1996-01-01

Characterizes specific spatial abilities required in geology studies through the examination of the performance of high school students in solving structural geology problems on the geologic spatial ability test (GeoSAT). Concludes that visual penetration ability and the ability to perceive the spatial configuration of the structure are…

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

International Nuclear Information System (INIS)

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

Study on the development of safety regulations for geological disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Wei Fangxin

2012-01-01

The development of regulations under Regulations on Safety Management of Radioactive Waste has become necessary as the issuance of it. The regulations related to geological disposal of high-level radioactive waste can promote the progress of research and development on geological disposal of high-level radioactive waste in China. This paper has present suggestions on development of regulations on geological disposal of high-level radioactive waste by analyzing development of safety regulations on geological disposal of high-level radioactive waste in foreign countries and problems occurred in China and discussed important issues related to the development of safety regulations on geological disposal of high-level radioactive waste. (author)

Wave Propagation in Jointed Geologic Media

Energy Technology Data Exchange (ETDEWEB)

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.

One perspective on spatial variability in geologic mapping

Science.gov (United States)

Markewich, H.W.; Cooper, S.C.

1991-01-01

This paper discusses some of the differences between geologic mapping and soil mapping, and how the resultant maps are interpreted. The role of spatial variability in geologic mapping is addressed only indirectly because in geologic mapping there have been few attempts at quantification of spatial differences. This is largely because geologic maps deal with temporal as well as spatial variability and consider time, age, and origin, as well as composition and geometry. Both soil scientists and geologists use spatial variability to delineate mappable units; however, the classification systems from which these mappable units are defined differ greatly. Mappable soil units are derived from systematic, well-defined, highly structured sets of taxonomic criteria; whereas mappable geologic units are based on a more arbitrary heirarchy of categories that integrate many features without strict values or definitions. Soil taxonomy is a sorting tool used to reduce heterogeneity between soil units. Thus at the series level, soils in any one series are relatively homogeneous because their range of properties is small and well-defined. Soil maps show the distribution of soils on the land surface. Within a map area, soils, which are often less than 2 m thick, show a direct correlation to topography and to active surface processes as well as to parent material.

Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. Part 1. Geological environment of Japan

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the geological disposal concept for high-level radioactive wastes (HLW) in Japan. The present document, the part 1 of the progress report, describes first in detail the role of geological environment in high-level radioactive wastes disposal, the features of Japanese geological environment, and programs to proceed the investigation in geological environment. The following chapter summarizes scientific basis for possible existence of stable geological environment, stable for a long period needed for the HLW disposal in Japan including such natural phenomena as volcano and faults. The results of the investigation of the characteristics of bed-rocks and groundwater are presented. These are important for multiple barrier system construction of deep geological disposal. The report furthermore describes the present status of technical and methodological progress in investigating geological environment and finally on the results of natural analog study in Tono uranium deposits area. (Ohno, S.)

Nitrate reduction in geologically heterogeneous catchments

DEFF Research Database (Denmark)

Refsgaard, Jens Christian; Auken, Esben; Bamberg, Charlotte A.

2014-01-01

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...... 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...

Geological exploration for a high-temperature aquifer thermal energy storage (HT-ATES) system: a case study from Oman

Science.gov (United States)

Winterleitner, Gerd; Schütz, Felina; Huenges, Ernst

2017-04-01

A collaborative research programme between the German Research Centre for Geoscience, Potsdam (GFZ) and The Research Council of Oman (TRC) is underway, which aims to develop and implement an innovative concept of a sustainable thermally driven cooling system in combination with a HT-ATES in northern Oman. The system will use an absorption chiller for cold supply, which nominally requires water of around 100°C as energy source. Solar collectors will provide this thermal energy and energy surpluses during daytimes will be stored to ensure a continuous operation of the cooling system. An integral part of this project is, therefore, the development of an efficient HT-ATES (100°C), which is based on temporary storage and recovery of thermal energy through hot water injection in subsurface aquifer horizons. Thus, an accurate thermal and fluid flow characterisation of potential reservoir horizons is essential to ensure optimal efficiency of the cooling system. The study area is located in the Al Khwad area, approximately 40 km to the west of Muscat. The area is characterised by a thick Cenozoic mixed carbonate-siliciclastic sedimentary succession, containing at least 3 aquifer horizons. We use a multidisciplinary approach for the initial ATES exploration and development phase, including traditional geological fieldwork dovetailed with virtual outcrop geology, thin-section analyses, geological modelling and reservoir fluid flow forecasting analyses. Our first results indicate two potential storage horizons: (1) a Miocene-aged clastic-dominated alluvial fan system and (2) an Eocene carbonate-dominated sequence. The alluvial fan system is characterised by a more than 300 m thick, coarse-clastic succession of coalesced individual fans. Thermal and hydraulic parameters are favourable for gravel and sandstone intervals but reservoir architecture is complex due to multiple generations of interconnecting fans with highly heterogeneous facies distributions. The Eocene carbonates

Safety assessment of HLW geological disposal system

International Nuclear Information System (INIS)

Naito, Morimasa

2006-01-01

In accordance with the Japanese nuclear program, the liquid waste with a high level of radioactivity arising from reprocessing is solidified in a stable glass matrix (vitrification) in stainless steel fabrication containers. The vitrified waste is referred to as high-level radioactive waste (HLW), and is characterized by very high initial radioactivity which, even though it decreases with time, presents a potential long-term risk. It is therefore necessary to thoroughly manage HLW from human and his environment. After vitrification, HLW is stored for a period of 30 to 50 years to allow cooling, and finally disposed of in a stable geological environment at depths greater than 300 m below surface. The deep underground environment, in general, is considered to be stable over geological timescales compared with surface environment. By selecting an appropriate disposal site, therefore, it is considered to be feasible to isolate the waste in the repository from man and his environment until such time as radioactivity levels have decayed to insignificance. The concept of geological disposal in Japan is similar to that in other countries, being based on a multibarrier system which combines the natural geological environment with engineered barriers. It should be noted that geological disposal concept is based on a passive safety system that does not require any institutional control for assuring long term environmental safety. To demonstrate feasibility of safe HLW repository concept in Japan, following technical steps are essential. Selection of a geological environment which is sufficiently stable for disposal (site selection). Design and installation of the engineered barrier system in a stable geological environment (engineering measures). Confirmation of the safety of the constructed geological disposal system (safety assessment). For site selection, particular consideration is given to the long-term stability of the geological environment taking into account the fact

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

Energy Technology Data Exchange (ETDEWEB)

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

Study on high-level waste geological disposal metadata model

International Nuclear Information System (INIS)

Ding Xiaobin; Wang Changhong; Zhu Hehua; Li Xiaojun

2008-01-01

This paper expatiated the concept of metadata and its researches within china and abroad, then explain why start the study on the metadata model of high-level nuclear waste deep geological disposal project. As reference to GML, the author first set up DML under the framework of digital underground space engineering. Based on DML, a standardized metadata employed in high-level nuclear waste deep geological disposal project is presented. Then, a Metadata Model with the utilization of internet is put forward. With the standardized data and CSW services, this model may solve the problem in the data sharing and exchanging of different data form A metadata editor is build up in order to search and maintain metadata based on this model. (authors)

Pore-scale studies of multiphase flow and reaction involving CO2 sequestration in geologic formations

Science.gov (United States)

Kang, Q.; Wang, M.; Lichtner, P. C.

2008-12-01

In geologic CO2 sequestration, pore-scale interfacial phenomena ultimately govern the key processes of fluid mobility, chemical transport, adsorption, and reaction. However, spatial heterogeneity at the pore scale cannot be resolved at the continuum scale, where averaging occurs over length scales much larger than typical pore sizes. Natural porous media, such as sedimentary rocks and other geological media encountered in subsurface formations, are inherently heterogeneous. This pore-scale heterogeneity can produce variabilities in flow, transport, and reaction processes that take place within a porous medium, and can result in spatial variations in fluid velocity, aqueous concentrations, and reaction rates. Consequently, the unresolved spatial heterogeneity at the pore scale may be important for reactive transport modeling at the larger scale. In addition, current continuum models of surface complexation reactions ignore a fundamental property of physical systems, namely conservation of charge. Therefore, to better understand multiphase flow and reaction involving CO2 sequestration in geologic formations, it is necessary to quantitatively investigate the influence of the pore-scale heterogeneity on the emergent behavior at the field scale. We have applied the lattice Boltzmann method to simulating the injection of CO2 saturated brine or supercritical CO2 into geological formations at the pore scale. Multiple pore-scale processes, including advection, diffusion, homogeneous reactions among multiple aqueous species, heterogeneous reactions between the aqueous solution and minerals, ion exchange and surface complexation, as well as changes in solid and pore geometry are all taken into account. The rich pore scale information will provide a basis for upscaling to the continuum scale.

Modeling study on geological environment at Horonobe URL site

International Nuclear Information System (INIS)

Shimo, Michito; Yamamoto, Hajime; Kumamoto, Sou; Fujiwara, Yasushi; Ono, Makoto

2005-02-01

The Horonobe underground research project has been operated by Japan Nuclear Cycle Development Institute to study the geological environment of sedimentary rocks in deep underground. The objectives of this study are to develop a geological environment model, which incorporate the current findings and the data obtained through the geological, geophysical, and borehole investigations at Horonobe site, and to predict the hydrological and geochemical impacts caused by the URL shaft excavation to the surrounding area. A three-dimensional geological structure model was constructed, integrating a large-scale model (25km x 15km) and a high-resolution site-scale model (4km x 4km) that have been developed by JNC. The constructed model includes surface topography, geologic formations (such as Yuchi, Koetoi, Wakkanai, and Masuporo Formations), and two major faults (Ohomagari fault and N1 fault). In hydrogeological modeling, water-conductive fractures identified in Wakkanai Formation are modeled stochastically using EHCM (Equivalent Heterogeneous Continuum Model) approach, to represent hydraulic heterogeneity and anisotropy in the fractured rock mass. Numerical code EQUIV FLO (Shimo et al., 1996), which is a 3D unsaturated-saturated groundwater simulator capable of EHCM, was used to simulate the regional groundwater flow. We used the same model and the code to predict the transient hydrological changes caused by the shaft excavations. Geochemical data in the Horonobe site such as water chemistries, mineral compositions of rocks were collected and summarized into digital datasets. M3 (Multivariate, Mixing and Mass-balance) method developed by SKB (Laaksoharju et al., 1999) was used to identify waters of different origins, and to infer the mixing ratio of these end-members to reproduce each sample's chemistry. Thermodynamic code such as RHREEQC, GWB, and EQ3/6 were used to model chemical reactions that explain the present minerals and aqueous concentrations observed in the site

On selection of geological medium for disposal of high-level radwaste

International Nuclear Information System (INIS)

Min Maozhong

1991-01-01

The present paper briefly reviews the suitability of some rocks as geological disposal repositories of high-level radwaste (HLW). The suitable rocks for geological ogi disposal of HLW are rock salt (salt diapir, bedded salt), granite, argillaceous rocks, tuff, basalt, gabbro, diabase, anhydrite, marine sedimentary rocks etc., especially, rock salt, granite, and argillaceous rocks. The data of principal hydraulic properties, mechanical-physical properties for various rocks in typical environment which might be considered for disposal purposes are also given in this paper. These data give a reference to China's geological disposal of HLW in the future

High throughput screening method for assessing heterogeneity of microorganisms

NARCIS (Netherlands)

Ingham, C.J.; Sprenkels, A.J.; van Hylckama Vlieg, J.E.T.; Bomer, Johan G.; de Vos, W.M.; van den Berg, Albert

2006-01-01

The invention relates to the field of microbiology. Provided is a method which is particularly powerful for High Throughput Screening (HTS) purposes. More specific a high throughput method for determining heterogeneity or interactions of microorganisms is provided.

CHARACTERIZATION OF GEOLOGICAL MATERIALS USING ION AND PHOTON BEAMS

International Nuclear Information System (INIS)

TOROK, SZ.B.; JONES, K.W.; TUNIZ, C.

1998-01-01

Geological specimens are often complex materials that require different analytical methods for their characterization. The parameters of interest may include the chemical composition of major, minor and trace elements. The chemical compounds incorporated in the minerals, the crystal structure and isotopic composition need to be considered. Specimens may be highly heterogeneous thus necessitating analytical methods capable of measurements on small sample volumes with high spatial resolution and sensitivity. Much essential information on geological materials can be obtained by using ion or photon beams. In this chapter we describe the principal analytical techniques based on particle accelerators, showing some applications that are hardly possible with conventional methods. In particular, the following techniques will be discussed: (1) Synchrotron radiation (SR) induced X-ray emission (SRIXE) and particle-induced X-ray emission (PEE) and other ion beam techniques for trace element analysis. (2) Accelerator mass spectrometry (AMS) for ultra sensitive analysis of stable nuclides and long-lived radionuclides. In most of the cases also the possibilities of elemental and isotopic analysis with high resolution will be discussed

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

Science.gov (United States)

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

2005-01-01

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.

Identifying and quantifying heterogeneity in high content analysis: application of heterogeneity indices to drug discovery.

Directory of Open Access Journals (Sweden)

Albert H Gough

Full Text Available One of the greatest challenges in biomedical research, drug discovery and diagnostics is understanding how seemingly identical cells can respond differently to perturbagens including drugs for disease treatment. Although heterogeneity has become an accepted characteristic of a population of cells, in drug discovery it is not routinely evaluated or reported. The standard practice for cell-based, high content assays has been to assume a normal distribution and to report a well-to-well average value with a standard deviation. To address this important issue we sought to define a method that could be readily implemented to identify, quantify and characterize heterogeneity in cellular and small organism assays to guide decisions during drug discovery and experimental cell/tissue profiling. Our study revealed that heterogeneity can be effectively identified and quantified with three indices that indicate diversity, non-normality and percent outliers. The indices were evaluated using the induction and inhibition of STAT3 activation in five cell lines where the systems response including sample preparation and instrument performance were well characterized and controlled. These heterogeneity indices provide a standardized method that can easily be integrated into small and large scale screening or profiling projects to guide interpretation of the biology, as well as the development of therapeutics and diagnostics. Understanding the heterogeneity in the response to perturbagens will become a critical factor in designing strategies for the development of therapeutics including targeted polypharmacology.

Operation environment construction of geological information database for high level radioactive waste geological disposal

International Nuclear Information System (INIS)

Wang Peng; Gao Min; Huang Shutao; Wang Shuhong; Zhao Yongan

2014-01-01

To fulfill the requirements of data storage and management in HLW geological disposal, a targeted construction method for data operation environment was proposed in this paper. The geological information database operation environment constructed by this method has its unique features. And it also will be the important support for HLW geological disposal project and management. (authors)

Key scientific challenges in geological disposal of high level radioactive waste

International Nuclear Information System (INIS)

Wang Ju

2007-01-01

The geological disposal of high radioactive waste is a challenging task facing the scientific and technical world. This paper introduces the latest progress of high level radioactive disposal programs in the latest progress of high level radioactive disposal programs in the world, and discusses the following key scientific challenges: (1) precise prediction of the evolution of a repository site; (2) characteristics of deep geological environment; (3) behaviour of deep rock mass, groundwater and engineering material under coupled con-ditions (intermediate to high temperature, geostress, hydraulic, chemical, biological and radiation process, etc); (4) geo-chemical behaviour of transuranic radionuclides with low concentration and its migration with groundwater; and (5) safety assessment of disposal system. Several large-scale research projects and several hot topics related with high-level waste disposal are also introduced. (authors)

High-Resolution Geologic Mapping of Martian Terraced Fan Deposits

Science.gov (United States)

Wolak, J. M.; Patterson, A. B.; Smith, S. D.; Robbins, N. N.

2018-06-01

This abstract documents our initial progress (year 1) mapping terraced fan features on Mars. Our objective is to investigate the role of fluids during fan formation and produce the first high-resolution geologic map (1:18k) of a terraced fan.

Influence of geologic layering on heat transport and storage in an aquifer thermal energy storage system

Science.gov (United States)

Bridger, D. W.; Allen, D. M.

2014-01-01

A modeling study was carried out to evaluate the influence of aquifer heterogeneity, as represented by geologic layering, on heat transport and storage in an aquifer thermal energy storage (ATES) system in Agassiz, British Columbia, Canada. Two 3D heat transport models were developed and calibrated using the flow and heat transport code FEFLOW including: a "non-layered" model domain with homogeneous hydraulic and thermal properties; and, a "layered" model domain with variable hydraulic and thermal properties assigned to discrete geological units to represent aquifer heterogeneity. The base model (non-layered) shows limited sensitivity for the ranges of all thermal and hydraulic properties expected at the site; the model is most sensitive to vertical anisotropy and hydraulic gradient. Simulated and observed temperatures within the wells reflect a combination of screen placement and layering, with inconsistencies largely explained by the lateral continuity of high permeability layers represented in the model. Simulation of heat injection, storage and recovery show preferential transport along high permeability layers, resulting in longitudinal plume distortion, and overall higher short-term storage efficiencies.

High-resolution charge carrier mobility mapping of heterogeneous organic semiconductors

Science.gov (United States)

Button, Steven W.; Mativetsky, Jeffrey M.

2017-08-01

Organic electronic device performance is contingent on charge transport across a heterogeneous landscape of structural features. Methods are therefore needed to unravel the effects of local structure on overall electrical performance. Using conductive atomic force microscopy, we construct high-resolution out-of-plane hole mobility maps from arrays of 5000 to 16 000 current-voltage curves. To demonstrate the efficacy of this non-invasive approach for quantifying and mapping local differences in electrical performance due to structural heterogeneities, we investigate two thin film test systems, one bearing a heterogeneous crystal structure [solvent vapor annealed 5,11-Bis(triethylsilylethynyl)anthradithiophene (TES-ADT)—a small molecule organic semiconductor] and one bearing a heterogeneous chemical composition [p-DTS(FBTTh2)2:PC71BM—a high-performance organic photovoltaic active layer]. TES-ADT shows nearly an order of magnitude difference in hole mobility between semicrystalline and crystalline areas, along with a distinct boundary between the two regions, while p-DTS(FBTTh2)2:PC71BM exhibits subtle local variations in hole mobility and a nanoscale domain structure with features below 10 nm in size. We also demonstrate mapping of the built-in potential, which plays a significant role in organic light emitting diode and organic solar cell operation.

International safeguards relevant to geologic disposal of high-level wastes and spent fuels

International Nuclear Information System (INIS)

Pillay, K.K.S.; Picard, R.R.

1989-01-01

Spent fuels from once-through fuel cycles placed in underground repositories have the potential to become attractive targets for diversion and/or theft because of their valuable material content and decreasing radioactivity. The first geologic repository in the US, as currently designed, will contain approximately 500 Mt of plutonium, 60,000 Mt of uranium and a host of other fissile and strategically important elements. This paper identifies some of the international safeguards issues relevant to the various proposed scenarios for disposing of the spent fuel. In the context of the US program for geologic disposal of spent fuels, this paper highlights several issues that should be addressed in the near term by US industries, the Department of Energy, and the Nuclear Regulatory Commission before the geologic repositories for spent fuels become a reality. Based on US spent fuel discharges, an example is presented to illustrate the enormity of the problem of verifying spent fuel inventories. The geologic disposal scenario for high-level wastes originating from defense facilities produced a ''practicably irrecoverable'' waste form. Therefore, safeguards issues for geologic disposal of high-level waste now in the US are less pressing. 56 refs. , 2 figs

A Geospatial Information Grid Framework for Geological Survey.

Science.gov (United States)

Wu, Liang; Xue, Lei; Li, Chaoling; Lv, Xia; Chen, Zhanlong; Guo, Mingqiang; Xie, Zhong

2015-01-01

The use of digital information in geological fields is becoming very important. Thus, informatization in geological surveys should not stagnate as a result of the level of data accumulation. The integration and sharing of distributed, multi-source, heterogeneous geological information is an open problem in geological domains. Applications and services use geological spatial data with many features, including being cross-region and cross-domain and requiring real-time updating. As a result of these features, desktop and web-based geographic information systems (GISs) experience difficulties in meeting the demand for geological spatial information. To facilitate the real-time sharing of data and services in distributed environments, a GIS platform that is open, integrative, reconfigurable, reusable and elastic would represent an indispensable tool. The purpose of this paper is to develop a geological cloud-computing platform for integrating and sharing geological information based on a cloud architecture. Thus, the geological cloud-computing platform defines geological ontology semantics; designs a standard geological information framework and a standard resource integration model; builds a peer-to-peer node management mechanism; achieves the description, organization, discovery, computing and integration of the distributed resources; and provides the distributed spatial meta service, the spatial information catalog service, the multi-mode geological data service and the spatial data interoperation service. The geological survey information cloud-computing platform has been implemented, and based on the platform, some geological data services and geological processing services were developed. Furthermore, an iron mine resource forecast and an evaluation service is introduced in this paper.

High-throughput heterogeneous catalyst research

Science.gov (United States)

Turner, Howard W.; Volpe, Anthony F., Jr.; Weinberg, W. H.

2009-06-01

With the discovery of abundant and low cost crude oil in the early 1900's came the need to create efficient conversion processes to produce low cost fuels and basic chemicals. Enormous investment over the last century has led to the development of a set of highly efficient catalytic processes which define the modern oil refinery and which produce most of the raw materials and fuels used in modern society. Process evolution and development has led to a refining infrastructure that is both dominated and enabled by modern heterogeneous catalyst technologies. Refineries and chemical manufacturers are currently under intense pressure to improve efficiency, adapt to increasingly disadvantaged feedstocks including biomass, lower their environmental footprint, and continue to deliver their products at low cost. This pressure creates a demand for new and more robust catalyst systems and processes that can accommodate them. Traditional methods of catalyst synthesis and testing are slow and inefficient, particularly in heterogeneous systems where the structure of the active sites is typically complex and the reaction mechanism is at best ill-defined. While theoretical modeling and a growing understanding of fundamental surface science help guide the chemist in designing and synthesizing targets, even in the most well understood areas of catalysis, the parameter space that one needs to explore experimentally is vast. The result is that the chemist using traditional methods must navigate a complex and unpredictable diversity space with a limited data set to make discoveries or to optimize known systems. We describe here a mature set of synthesis and screening technologies that together form a workflow that breaks this traditional paradigm and allows for rapid and efficient heterogeneous catalyst discovery and optimization. We exemplify the power of these new technologies by describing their use in the development and commercialization of a novel catalyst for the

Nanoscale high-content analysis using compositional heterogeneities of single proteoliposomes

DEFF Research Database (Denmark)

Mathiasen, Signe; Christensen, Sune M.; Fung, Juan José

2014-01-01

Proteoliposome reconstitution is a standard method to stabilize purified transmembrane proteins in membranes for structural and functional assays. Here we quantified intrareconstitution heterogeneities in single proteoliposomes using fluorescence microscopy. Our results suggest that compositional...... heterogeneities can severely skew ensemble-average proteoliposome measurements but also enable ultraminiaturized high-content screens. We took advantage of this screening capability to map the oligomerization energy of the β2-adrenergic receptor using ∼10(9)-fold less protein than conventional assays....

Monitoring of geological repositories for high level radioactive waste

International Nuclear Information System (INIS)

2001-04-01

Geological repositories for disposal of high level radioactive waste are designed to provide isolation of the waste from human environment for many thousands of years. This report discusses the possible purposes for monitoring geological repositories at the different stages of a repository programme, the use that may be made of the information obtained and the techniques that might be applied. This report focuses on the different objectives that monitoring might have at various stages of a programme, from the initiation of work on a candidate site, to the period after repository closure. Each objective may require somewhat different types of information, or may use the same information in different ways. Having evaluated monitoring requirements, the report concludes with a brief evaluation of available monitoring techniques

Geological aspects of the high level waste and spent fuel disposal programme in Slovakia

Energy Technology Data Exchange (ETDEWEB)

Matej, Gedeon; Milos, Kovacik; Jozef, Hok [Geological Survey of Slovak Republic, Bratislava (Slovakia)

2001-07-01

An autonomous programme for development of a deep geological high level waste and spent fuel disposal began in 1996. One of the most important parts in the programme is siting of the future deep seated disposal. Geological conditions in Slovakia are complex due to the Alpine type tectonics that formed the geological environment during Tertiary. Prospective areas include both crystalline complexes (tonalites, granites, granodiorites) and Neogene (Miocene) argillaceous complexes. (author)

Laboratory investigations of the effects of geologic heterogeneity on groundwater salinization and flush-out times from a tsunami-like event.

Science.gov (United States)

Vithanage, M; Engesgaard, P; Jensen, K H; Illangasekare, T H; Obeysekera, J

2012-08-01

This intermediate scale laboratory experimental study was designed to improve the conceptual understanding of aquifer flushing time associated with diffuse saltwater contamination of coastal aquifers due to a tsunami-like event. The motivation comes from field observations made after the tsunami in December, 2004 in South Asia. The focus is on the role and effects of heterogeneity on flushing effectiveness. A scheme that combines experimentation in a 4.8m long laboratory tank and numerical modeling was used. To demonstrate the effects of geologic heterogeneity, plume migration and flushing times were analyzed in both homogeneous and layered media and under different boundary conditions (ambient flow, saltwater infiltration rate, freshwater recharge). Saltwater and freshwater infiltrations imitate the results of the groundwater salinization from the tsunami and freshening from the monsoon rainfall. The saltwater plume behavior was monitored both through visual observations (digital photography) of the dyed salt water and using measurements taken from several electrical conductivity sensors installed through the tank walls. The variable-density, three dimensional code HST3D was used to simulate the tank experiments and understand the fate and movement of the saltwater plume under field conditions. The results from the tank experiments and modeling demonstrated that macro-scale heterogeneity significantly influenced the migration patterns and flushing times of diffuse saltwater contamination. Ambient flow had a direct influence on total flush-out time, and heterogeneity impacted flush-out times for the top part of the tank and total flush-out times. The presence of a continuous low-permeability layer caused a 40% increase in complete flush-out time due to the slower flow of salt water in the low-permeability layer. When a relatively small opening was introduced in the low-permeability layer, salt water migrated quickly into a higher-permeable layer below causing a

Should the U.S. proceed to consider licensing deep geological disposal of high-level nuclear waste

International Nuclear Information System (INIS)

Curtiss, J.R.

1993-01-01

The United States, as well as other countries facing the question of how to handle high-level nuclear waste, has decided that the most appropriate means of disposal is in a deep geologic repository. In recent years, the Radioactive Waste Management Committee of the Nuclear Energy Agency has developed several position papers on the technical achievability of deep geologic disposal, thus demonstrating the serious consideration of deep geologic disposal in the international community. The Committee has not, as yet, formally endorsed disposal in a deep geologic repository as the preferred method of handling high-level nuclear waste. The United States, on the other hand, has studied the various methods of disposing of high-level nuclear waste, and has determined that deep geologic disposal is the method that should be developed. The purpose of this paper is to present a review of the United States' decision on selecting deep geologic disposal as the preferred method of addressing the high-level waste problem. It presents a short history of the steps taken by the U.S. in determining what method to use, discusses the NRC's waste Confidence Decision, and provides information on other issues in the U.S. program such as reconsideration of the final disposal standard and the growing inventory of spent fuel in storage

The geological basis and the representation of spatial variability in fractured media

International Nuclear Information System (INIS)

Mazurek, M.; Gautschi, A.; Zuidema, P.

1998-01-01

Spatial variability of features and parameters relevant for contaminant transport modelling occurs on all scales of interest for the quantification of processes that govern solute migration, typically decimeters to hundreds of meters. Two types of spatial variability are distinguished, namely the internal heterogeneity of each individual water-conducting feature (e.g. the complex architecture of a fault) and the larger-scale heterogeneity that results from the groundwater flow through different types of water-conducting features along the flow-path from the repository to the discharge areas. An up-scaling procedure is required to obtain hydraulic parameters and the properties of the overall flow-path, whereas the heterogeneity of many other geologic features (geometry of flow and matrix porosity, mineralogy, etc.) can be fed directly into coupled codes that quantify radionuclide transport. The procedures needed to derive conceptual models integrating geological and hydraulic field measurements and observations at a given site are illustrated by examples from both crystalline and sedimentary rock formations. (author)

Modeling heterogeneous unsaturated porous media flow at Yucca Mountain

International Nuclear Information System (INIS)

Robey, T.H.

1994-01-01

Geologic systems are inherently heterogeneous and this heterogeneity can have a significant impact on unsaturated flow through porous media. Most previous efforts to model groundwater flow through Yucca Mountain have used stratigraphic units with homogeneous properties. However, modeling heterogeneous porous and fractured tuff in a more realistic manner requires numerical methods for generating heterogeneous simulations of the media, scaling of material properties from core scale to computational scale, and flow modeling that allows channeling. The Yucca Mountain test case of the INTRAVAL project is used to test the numerical approaches. Geostatistics is used to generate more realistic representations of the stratigraphic units and heterogeneity within units is generated using sampling from property distributions. Scaling problems are reduced using an adaptive grid that minimizes heterogeneity within each flow element. A flow code based on the dual mixed-finite-element method that allows for heterogeneity and channeling is employed. In the Yucca Mountain test case, the simulated volumetric water contents matched the measured values at drill hole USW UZ-16 except in the nonwelded portion of Prow Pass

Applications of Micro-Fourier Transform Infrared Spectroscopy (FTIR) in the Geological Sciences—A Review

Science.gov (United States)

Chen, Yanyan; Zou, Caineng; Mastalerz, Maria; Hu, Suyun; Gasaway, Carley; Tao, Xiaowan

2015-01-01

Fourier transform infrared spectroscopy (FTIR) can provide crucial information on the molecular structure of organic and inorganic components and has been used extensively for chemical characterization of geological samples in the past few decades. In this paper, recent applications of FTIR in the geological sciences are reviewed. Particularly, its use in the characterization of geochemistry and thermal maturation of organic matter in coal and shale is addressed. These investigations demonstrate that the employment of high-resolution micro-FTIR imaging enables visualization and mapping of the distributions of organic matter and minerals on a micrometer scale in geological samples, and promotes an advanced understanding of heterogeneity of organic rich coal and shale. Additionally, micro-FTIR is particularly suitable for in situ, non-destructive characterization of minute microfossils, small fluid and melt inclusions within crystals, and volatiles in glasses and minerals. This technique can also assist in the chemotaxonomic classification of macrofossils such as plant fossils. These features, barely accessible with other analytical techniques, may provide fundamental information on paleoclimate, depositional environment, and the evolution of geological (e.g., volcanic and magmatic) systems. PMID:26694380

Research on geological disposal: R and D concept on geological disposal

International Nuclear Information System (INIS)

1993-01-01

The objective on geological disposal of high-level radioactive wastes are to ensure the long term radiological protection of the human and his environment in accordance with current internationally agreed radiation protection principles. The principle of geological disposal is to settle the high-level wastes in deep underground so as to isolate them from the human and his environment considering the existence of groundwater. Japan is currently in the stage of assessing technical feasibility of geological disposal to the extent practicable. In accordance with the AEC (Atomic Energy Commission) policy in 1989, PNC (Power Reactor and Nuclear Fuel Development Corporation) has conducted the research and development on geological disposal in three areas: 1) studies of geological environment, 2) research and development of disposal technology, and 3) performance assessment study. (author)

A safe, efficient and cost effective process for removing petroleum hydrocarbons from a highly heterogeneous and relatively inaccessible shoreline.

Science.gov (United States)

Guerin, Turlough F

2015-10-01

A rocky, intractable and highly heterogeneous, intertidal zone, was contaminated from a diesel fuel spill that occurred during refuelling of a grader used in road construction, on an operational mine's shiploading facility. A practical, cost-effective, and safer (to personnel by avoiding drilling and earthworks), and non-invasive sampling and remediation strategy was designed and implemented since the location and nature of the impacted geology (rock fill) and sediment, precluded conventional ex-situ and any in-situ treatment where drilling would be required. Enhanced biostimulation with surfactant, available N & P (which were highly constrained), and increased aeration, increased the degradation rate from no discernable change for 2 years post-spill, to 170 mg/kg/day; the maximum degradation rate after intervention. While natural attenuation was ineffective in this application, the low-cost, biostimulation intervention proved successful, allowing the site owner to meet their regulatory obligations. Petroleum hydrocarbons (aliphatic fraction) decreased from ∼20,000 mg/kg to <200 mg/kg at the completion of 180 weeks of treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

KAUST Repository

Gasda, S. E.; Nordbotten, J. M.; Celia, M. A.

2009-01-01

equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid

Probing the structure of heterogeneous diluted materials by diffraction tomography.

Science.gov (United States)

Bleuet, Pierre; Welcomme, Eléonore; Dooryhée, Eric; Susini, Jean; Hodeau, Jean-Louis; Walter, Philippe

2008-06-01

The advent of nanosciences calls for the development of local structural probes, in particular to characterize ill-ordered or heterogeneous materials. Furthermore, because materials properties are often related to their heterogeneity and the hierarchical arrangement of their structure, different structural probes covering a wide range of scales are required. X-ray diffraction is one of the prime structural methods but suffers from a relatively poor detection limit, whereas transmission electron analysis involves destructive sample preparation. Here we show the potential of coupling pencil-beam tomography with X-ray diffraction to examine unidentified phases in nanomaterials and polycrystalline materials. The demonstration is carried out on a high-pressure pellet containing several carbon phases and on a heterogeneous powder containing chalcedony and iron pigments. The present method enables a non-invasive structural refinement with a weight sensitivity of one part per thousand. It enables the extraction of the scattering patterns of amorphous and crystalline compounds with similar atomic densities and compositions. Furthermore, such a diffraction-tomography experiment can be carried out simultaneously with X-ray fluorescence, Compton and absorption tomographies, enabling a multimodal analysis of prime importance in materials science, chemistry, geology, environmental science, medical science, palaeontology and cultural heritage.

Deep geologic storage of high level radioactive wastes: conceptual generic designs

International Nuclear Information System (INIS)

1995-01-01

This report summarizes the studies on deep geologic storage of radioactive wastes and specially for the high-level radioactive wastes. The study is focussed to the geotechnical assessment and generic-conceptual designs. Methodology analysis, geotechnical feasibility, costs and operation are studied

A Corner-Point-Grid-Based Voxelization Method for Complex Geological Structure Model with Folds

Science.gov (United States)

Chen, Qiyu; Mariethoz, Gregoire; Liu, Gang

2017-04-01

3D voxelization is the foundation of geological property modeling, and is also an effective approach to realize the 3D visualization of the heterogeneous attributes in geological structures. The corner-point grid is a representative data model among all voxel models, and is a structured grid type that is widely applied at present. When carrying out subdivision for complex geological structure model with folds, we should fully consider its structural morphology and bedding features to make the generated voxels keep its original morphology. And on the basis of which, they can depict the detailed bedding features and the spatial heterogeneity of the internal attributes. In order to solve the shortage of the existing technologies, this work puts forward a corner-point-grid-based voxelization method for complex geological structure model with folds. We have realized the fast conversion from the 3D geological structure model to the fine voxel model according to the rule of isocline in Ramsay's fold classification. In addition, the voxel model conforms to the spatial features of folds, pinch-out and other complex geological structures, and the voxels of the laminas inside a fold accords with the result of geological sedimentation and tectonic movement. This will provide a carrier and model foundation for the subsequent attribute assignment as well as the quantitative analysis and evaluation based on the spatial voxels. Ultimately, we use examples and the contrastive analysis between the examples and the Ramsay's description of isoclines to discuss the effectiveness and advantages of the method proposed in this work when dealing with the voxelization of 3D geologic structural model with folds based on corner-point grids.

Geological Geophysical and structural studies in Mina Ratones (Pluton de Albala)

International Nuclear Information System (INIS)

Perez-Estaun, A.; Carbonell, R.; Marti, D.; Flecha, I.; Escuder Viruete, J.

2002-01-01

Mina Ratones environmental restoration project included petrological, structural,geophysical, hydrogeological and hydrogeochemical studies. The main objective of the geologic-structural and geophysical studies was the Albala granite structural characterization around the Mina Ratones uranium mine. The location of facies, fault zones (faults and dykes) as well as the distribution of some physical properties inside the rock massif was obtained for a granitic black of 900, 500, and 500 m. The geologic-structural and geophysical techniques applied to Mina Ratones provided a multidisciplinary approach for high resolution characterization of rock massif, and the structures potentially containing fluids,able to be applied to the hydrogeological modelling to a particular area. Geological studies included a detailed structural mapping of the area surrounding the mine (1:5,000 scale), the geometric, kinematics, and dynamics analysis of fractures of all scales, the petrology and geochemistry of fault rocks and altered areas surrounding fractures, and the microstructural studies of samples from surface and core lags. The construction of geostatistical models in two and three dimensions had helped to characterize the Mina Ratones rock massif showing the spatial distribution of fault zones, fracture intensity, granite composition heterogeneities, fluid-rock interaction zones, and physical properties. (Author)

Concept on groundwater flow and mass transport through heterogeneous porous media and application to in-situ test analysis

International Nuclear Information System (INIS)

Hatanaka, Koichiro; Umeki, Hiroyuki.

1995-01-01

Generally, geological media is modelled as porous or fractured media depending on their characteristics. Since the channels of groundwater flow and the transport paths are determined by the heterogeneity of the geological media, quantitative understanding of the heterogeneity is an important issue for modelling flow and transport processes through them. Therefore, it becomes popular way to develop statistical identification approaches of the heterogeneous field by using data from in-situ test and conduct validation studies of flow and transport models through the field by comparing with observed data. In this report, the theories of the identification approach and the concept on groundwater flow and mass transport are explained briefly and the application to tracer tests conducted at Grimsel test site, Switzerland, are described. (author)

Applications of Micro-Fourier Transform Infrared Spectroscopy (FTIR in the Geological Sciences—A Review

Directory of Open Access Journals (Sweden)

Yanyan Chen

2015-12-01

Full Text Available Fourier transform infrared spectroscopy (FTIR can provide crucial information on the molecular structure of organic and inorganic components and has been used extensively for chemical characterization of geological samples in the past few decades. In this paper, recent applications of FTIR in the geological sciences are reviewed. Particularly, its use in the characterization of geochemistry and thermal maturation of organic matter in coal and shale is addressed. These investigations demonstrate that the employment of high-resolution micro-FTIR imaging enables visualization and mapping of the distributions of organic matter and minerals on a micrometer scale in geological samples, and promotes an advanced understanding of heterogeneity of organic rich coal and shale. Additionally, micro-FTIR is particularly suitable for in situ, non-destructive characterization of minute microfossils, small fluid and melt inclusions within crystals, and volatiles in glasses and minerals. This technique can also assist in the chemotaxonomic classification of macrofossils such as plant fossils. These features, barely accessible with other analytical techniques, may provide fundamental information on paleoclimate, depositional environment, and the evolution of geological (e.g., volcanic and magmatic systems.

Tracing contaminant pathways in sandy heterogeneous glaciofluvial sediments using a sedimentary depositional model

International Nuclear Information System (INIS)

Webb, E.K.; Anderson, M.P.

1990-01-01

Heterogeneous sedimentary deposits present complications for tracking contaminant movement by causing a complex advective flow field. Connected areas of high conductivity produce so-called fast paths that control movement of solutes. Identifying potential fast paths and describing the variation in hydraulic properties was attempted through simulating the deposition of a glaciofluvial deposit (outwash). Glaciofluvial deposits usually consist of several depositional facies, each of which has different physical characteristics, depositional structures and hydraulic properties. Therefore, it is unlikely that the property of stationarity (a constant mean hydraulic conductivity and a mono-modal probability distribution) holds for an entire glaciofluvial sequence. However, the process of dividing an outwash sequence into geologic facies presumably identifies units of material with similar physical characteristics. It is proposed that patterns of geologic facies determined by field observation can be quantified by mathematical simulation of sediment deposition. Subsequently, the simulated sediment distributions can be used to define the distribution of hydrogeologic parameters and locate possible fast paths. To test this hypothesis, a hypothetical glacial outwash deposit based on geologic facies descriptions contained in the literature was simulated using a sedimentary depositional model, SEDSIM, to produce a three-dimensional description of sediment grain size distributions. Grain size distributions were then used to estimate the spatial distribution of hydraulic conductivity. Subsequently a finite-difference flow model and linked particle tracking algorithm were used to trace conservative transport pathways. This represents a first step in describing the spatial heterogeneity of hydrogeologic characteristics for glaciofluvial and other braided stream environments. (Author) (39 refs., 7 figs.)

A method for geological hazard extraction using high-resolution remote sensing

International Nuclear Information System (INIS)

Wang, Q J; Chen, Y; Bi, J T; Lin, Q Z; Li, M X

2014-01-01

Taking Yingxiu, the epicentre of the Wenchuan earthquake, as the study area, a method for geological disaster extraction using high-resolution remote sensing imagery was proposed in this study. A high-resolution Digital Elevation Model (DEM) was used to create mask imagery to remove interfering factors such as buildings and water at low altitudes. Then, the mask imagery was diced into several small parts to reduce the large images' inconsistency, and they were used as the sources to be classified. After that, vector conversion was done on the classified imagery in ArcGIS. Finally, to ensure accuracy, other interfering factors such as buildings at high altitudes, bare land, and land covered by little vegetation were removed manually. Because the method can extract geological hazards in a short time, it is of great importance for decision-makers and rescuers who need to know the degree of damage in the disaster area, especially within 72 hours after an earthquake. Therefore, the method will play an important role in decision making, rescue, and disaster response planning

Site selection factors for repositories of solid high-level and alpha-bearing wastes in geological formations

International Nuclear Information System (INIS)

1977-01-01

The purpose of this report is to provide guidelines for the selection and evaluation of suitable areas and sites for the disposal of solid high-level and alpha-bearing wastes into geological formations. This report is also intended to provide summary information on many types of geological formations underlying the land masses that might be considered as well as guidance on the geological and hydrological factors that should be investigated to demonstrate the suitability of the formations. In addition, other factors that should be considered in selecting a site for a radioactive waste repository are discussed briefly. The information, as presented, was developed to the extent of current technology for application to the evaluation of deep (greater than about 300 metres below ground level) geological formations in the selection of suitable areas for the disposal of solid or solidified high-level and alpha-bearing wastes. The extreme complexity of many geological environments and of the rock features that govern the presence and circulation of groundwater does not make it feasible to derive strict criteria for the selection of a site for a radioactive waste repository in a geological formation. Each potential repository location must be evaluated according to its own unique geological and hydrological setting. Therefore, only general guidance is offered, and this is done through discussion of the many factors that need to be considered in order to obtain the necessary assurances that the radionuclides will be confined in the geological repository over the required period of time

Site selection factors for repositories of solid high-level and alpha-bearing wastes in geological formations

Energy Technology Data Exchange (ETDEWEB)

1977-01-01

The purpose of this report is to provide guidelines for the selection and evaluation of suitable areas and sites for the disposal of solid high-level and alpha-bearing wastes into geological formations. This report is also intended to provide summary information on many types of geological formations underlying the land masses that might be considered as well as guidance on the geological and hydrological factors that should be investigated to demonstrate the suitability of the formations. In addition, other factors that should be considered in selecting a site for a radioactive waste repository are discussed briefly. The information, as presented, was developed to the extent of current technology for application to the evaluation of deep (greater than about 300 meters below ground level) geological formations in the selection of suitable areas for the disposal of solid or solidified high-level and alpha-bearing wastes. The extreme complexity of many geological environments and of the rock features that govern the presence and circulation of groundwater does not make it feasible to derive strict criteria for the selection of a site for a radioactive waste repository in a geological formation. Each potential repository location must be evaluated according to its own unique geological and hydrological setting. Therefore, only general guidance is offered, and this is done through discussion of the many factors that need to be considered in order to obtain the necessary assurances that the radionuclides will be confined in the geological repository over the required period of time.

Up-scaling of a two-phase flow model including gravity effect in geological heterogeneous media: application to CO2 sequestration

International Nuclear Information System (INIS)

Ngo, Tri-Dat

2016-01-01

This work deals with the mathematical modeling and the numerical simulation of the migration under gravity and capillarity effects of the supercritical CO 2 injected into a geological heterogeneous sequestration site. The simulations are performed with the code DuMux. Particularly, we consider the up-scaling, from the cell scale to the reservoir scale, of a two-phase (CO 2 -brine) flow model within a periodic stratified medium made up of horizontal low permeability barriers, continuous or discontinuous. The up-scaling is done by the two-scale asymptotic method. First, we consider perfectly layered media. An homogenized model is developed and validated by numerical simulation for different values of capillary number and the incident flux of CO 2 . The homogenization method is then applied to the case of a two-dimensional medium made up of discontinuous layers. Due to the gravity effect, the CO 2 accumulates under the low permeability layers, which leads to a non-standard local mathematical problem. This stratification is modeled using the gravity current approach. This approach is then extended to the case of semi-permeable strata taking into account the capillarity. The up-scaled model is compared with numerical simulations for different types of layers, with or without capillary pressure, and its limit of validity is discussed in each of these cases. The final part of this thesis is devoted to the study of the parallel computing performances of the code DuMux to simulate the injection and migration of CO 2 in three-dimensional heterogeneous media (layered periodic media, fluvial media and reservoir model SPE 10). (author) [fr

Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. An extra issue: background of the geological disposal

International Nuclear Information System (INIS)

1999-11-01

Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the geological disposal concept for high-level radioactive wastes (HLW) in Japan. The present document, an extra issue of the progress report, was prepared for the expected readers of the report to have background information on the geological disposal. Thus it gives information about (1) generation of high-level radioactive wastes, (2) history of plans proposed for HLW disposal in Japan, and (3) procedure until the geological disposal plan is finally adopted and basic future schedules. It further discusses on such problems in HLW treatment and disposal, as for example a problem of reliable safety for a very long period. (Ohno, S.)

Preliminary consideration for research on geological disposal of high-level radioactive waste in China in the period of 2000-2040

International Nuclear Information System (INIS)

Xu Guoqing

2004-01-01

Based on the overseas practical experiences with combination of domestic realistic conditions a preliminary consideration of a long-range plan is proposed for research on geological disposal of high-level radioactive waste in China in the period of 2000-2040. An overview of research on geological disposal of high-level radioactive waste in the overseas and mainland is presented shortly first in this paper. Then the discussion is centered on the preliminary consideration of a long-range plan for research on geological disposal of high-level radioactive waste in China. The partition of stages of research on geological disposal of high-level radioactive waste, the goal, task, research contents and time table for each research stage is stated in this preliminary consideration. The data mentioned above will probably be useful for making plan for geological disposal of high-level radioactive waste in the future in China. (author)

CIGeO geological disposal for high-level radioactive waste in France

International Nuclear Information System (INIS)

Ouzounian, Gerald; Bolia, Jelana

2014-01-01

Andra is the sole French organization responsible for the radioactive waste management in the country. Its work relies extensively on the legal basis provided by several major laws (Waste Act of 1991 and the Planning Act of 2006), which shaped the main principles of the waste management strategy and determined the corresponding implementation tools. Andra's industrial activities are essentially based around three of its national disposal facilities. Two of these operational facilities, by their design and comprehensive monitoring system, are considered worldwide as solid and proven reference solutions for the concerned types of radioactive waste. Andra is also charged with designing a future deep geological repository for intermediate-level long-lived and high-level waste and researching potential management and disposal solutions for the graphite and radium-bearing waste. The purpose of this article is to update the information to the readers about the Cigeo geological disposal project for high-level radioactive waste in France (authors)

Transitioning Groundwater from an Extractive Resource to a Managed Water Storage Resource: Geology and Recharge in Sedimentary Basins

Science.gov (United States)

Maples, S.; Fogg, G. E.; Maxwell, R. M.; Liu, Y.

2017-12-01

Civilizations have typically obtained water from natural and constructed surface-water resources throughout most of human history. Only during the last 50-70 years has a significant quantity of water for humans been obtained through pumping from wells. During this short time, alarming levels of groundwater depletion have been observed worldwide, especially in some semi-arid and arid regions that rely heavily on groundwater pumping from clastic sedimentary basins. In order to reverse the negative effects of over-exploitation of groundwater resources, we must transition from treating groundwater mainly as an extractive resource to one in which recharge and subsurface storage are pursued more aggressively. However, this remains a challenge because unlike surface-water reservoirs which are typically replenished over annual timescales, the complex geologic architecture of clastic sedimentary basins impedes natural groundwater recharge rates resulting in decadal or longer timescales for aquifer replenishment. In parts of California's Central Valley alluvial aquifer system, groundwater pumping has outpaced natural groundwater recharge for decades. Managed aquifer recharge (MAR) has been promoted to offset continued groundwater overdraft, but MAR to the confined aquifer system remains a challenge because multiple laterally-extensive silt and clay aquitards limit recharge rates in most locations. Here, we simulate the dynamics of MAR and identify potential recharge pathways in this system using a novel combination of (1) a high-resolution model of the subsurface geologic heterogeneity and (2) a physically-based model of variably-saturated, three-dimensional water flow. Unlike most groundwater models, which have coarse spatial resolution that obscures the detailed subsurface geologic architecture of these systems, our high-resolution model can pinpoint specific geologic features and locations that have the potential to `short-circuit' aquitards and provide orders

Hydraulic Parameter Generation Technique Using a Discrete Fracture Network with Bedrock Heterogeneity in Korea

Directory of Open Access Journals (Sweden)

Jae-Yeol Cheong

2017-12-01

Full Text Available In instances of damage to engineered barriers containing nuclear waste material, surrounding bedrock is a natural barrier that retards radionuclide movement by way of adsorption and delay due to groundwater flow through highly tortuous fractured rock pathways. At the Gyeongju nuclear waste disposal site, groundwater mainly flows through granitic and sedimentary rock fractures. Therefore, to understand the nuclide migration path, it is necessary to understand discrete fracture networks based on heterogeneous fracture orientations, densities, and size characteristics. In this study, detailed heterogeneous fracture distribution, including the density and orientation of the fractures, was considered for a region that has undergone long periods of change from various geological activities at and around the Gyeongju site. A site-scale discrete fracture network (DFN model was constructed taking into account: (i regional fracture heterogeneity constrained by a multiple linear regression analysis of fracture intensity on faults and electrical resistivity; and (ii the connectivity of conductive fractures having fracture hydraulic parameters, using transient flow simulation. Geometric and hydraulic heterogeneity of the DFN was upscaled into equivalent porous media for flow and transport simulation for a large-scale model.

The general situation of clay site for high-level waste geological disposal repository

International Nuclear Information System (INIS)

Wang Changxuan; Liu Xiaodong; Liu Pinghui

2008-01-01

Host medium is vitally important for safety of high-level radiaoactive waste (HLW) geological disposal. Clay, as host media of geological repository of HLW, has received greater attention for its inherent advantages. This paper summarizes IAEA and OECD/NEA's some safety guides on site selection and briefly introduces the process of the site selection, their studies and the characteristics of the clay formations in Switz-erland, France and Belgian. Based on these analyses, some suggestions are made to China's HLW repository clay site selection. (authors)

Geologic disposal as optimal solution of managing the spent nuclear fuel and high-level radioactive waste

International Nuclear Information System (INIS)

Ilie, P.; Didita, L.; Ionescu, A.; Deaconu, V.

2002-01-01

To date there exist three alternatives for the concept of geological disposal: 1. storing the high-level waste (HLW) and spent nuclear fuel (SNF) on ground repositories; 2. solutions implying advanced separation processes including partitioning and transmutation (P and T) and eventual disposal in outer space; 3. geological disposal in repositories excavated in rocks. Ground storing seems to be advantageous as it ensures a secure sustainable storing system over many centuries (about 300 years). On the other hand ground storing would be only a postponement in decision making and will be eventually followed by geological disposal. Research in the P and T field is expected to entail a significant reduction of the amount of long-lived radioactive waste although the long term geological disposal will be not eliminated. Having in view the high cost, as well as the diversity of conditions in the countries owning power reactors it appears as a reasonable regional solution of HLW disposal that of sharing a common geological disposal. In Romania legislation concerning of radioactive waste is based on the Law concerning Spent Nuclear Fuel and Radioactive Waste Management in View of Final Disposal. One admits at present that for Romania geological disposal is not yet a stressing issue and hence intermediate ground storing of SNF will allow time for finding a better final solution

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors

DEFF Research Database (Denmark)

Andersen, Thomas; Jensen, Robert; Christensen, M. K.

2012-01-01

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal...

Spatial Heterogeneity of Water Quality in a Highly Degraded Tropical Freshwater Ecosystem

Science.gov (United States)

Zambrano, Luis; Contreras, Victoria; Mazari-Hiriart, Marisa; Zarco-Arista, Alba E.

2009-02-01

Awareness of environmental heterogeneity in ecosystems is critical for management and conservation. We used the Xochimilco freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD = 0.4 ), warm (17°C, SD = 2.9), well oxygenated (5.0 mg l-1, SD = 3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO3-N = 15.9 mg l-1, SD=13.7; NH4-N = 2.88 mg l-1, SD = 4.24; and PO4-P = 8.3 mg l-1, SD = 2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.

Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. Part 3. Safety assessment for geological disposal systems

International Nuclear Information System (INIS)

1999-11-01

Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the geological disposal concept for high-level radioactive wastes (HLW) in Japan. The present document, the part 3 of the progress report, concerns safety assessment for geological disposal systems definitely introduced in part 1 and 2 of this series and consists of 9 chapters. Chapter I concerns the methodology for safety assessment while Chapter II deals with diversity and uncertainty about the scenario, the adequate model and the required data of the systems above. Chapter III summarizes the components of the geological disposal system. Chapter IV refers to the relationship between radioactive wastes and human life through groundwater, i.e. nuclide migration. In Chapter V is made a reference case which characterizes the geological environmental data using artificial barrier specifications. (Ohno. S.)

Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste

International Nuclear Information System (INIS)

Murphy, W.M.; Kovach, L.A.

1995-01-01

A workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste (HLW) was held in San Antonio, Texas, on July 22-25, 1991. It was sponsored by the US Nuclear Regulatory Commission (NRC) and the Center for Nuclear Waste Regulatory Analyses (CNWRA). Invitations to the workshop were extended to a large number of individuals with a variety of technical and professional interests related to geologic disposal of nuclear waste and natural analog studies. The objective of the workshop was to examine the role of natural analog studies in performance assessment, site characterization, and prioritization of research related to geologic disposal of HLW

Confabulation Based Real-time Anomaly Detection for Wide-area Surveillance Using Heterogeneous High Performance Computing Architecture

Science.gov (United States)

2015-06-01

CONFABULATION BASED REAL-TIME ANOMALY DETECTION FOR WIDE-AREA SURVEILLANCE USING HETEROGENEOUS HIGH PERFORMANCE COMPUTING ARCHITECTURE SYRACUSE...DETECTION FOR WIDE-AREA SURVEILLANCE USING HETEROGENEOUS HIGH PERFORMANCE COMPUTING ARCHITECTURE 5a. CONTRACT NUMBER FA8750-12-1-0251 5b. GRANT...processors including graphic processor units (GPUs) and Intel Xeon Phi processors. Experimental results showed significant speedups, which can enable

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

Science.gov (United States)

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

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

Energy Technology Data Exchange (ETDEWEB)

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.

Site characterization information needs for a high-level waste geologic repository

International Nuclear Information System (INIS)

Gupta, D.C.; Nataraja, M.S.; Justus, P.S.

1987-01-01

At each of the three candidate sites recommended for site characterization for High-Level Waste Geologic Repository development, the DOE has proposed to conduct both surface-based testing and in situ exploration and testing at the depths that wastes would be emplaced. The basic information needs and consequently the planned surface-based and in situ testing program will be governed to a large extent by the amount of credit taken for individual components of the geologic repository in meeting the performance objectives and siting criteria. Therefore, identified information to be acquired from site characterization activities should be commensurate with DOE's assigned performance goals for the repository system components on a site-specific basis. Because of the uncertainties that are likely to be associated with initial assignment of performance goals, the information needs should be both reasonably and conservatively identified

Present situation and perspective of China's geological disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Zhang, H.

2005-01-01

The theme of the conference, 'Political and Technical Progress of Geologic Repositories', has drawn world-wide attention and remains a challenging topic facing the nuclear industry. I am delighted to attend this important conference and have the opportunity to state our views. And I would like to express my gratitude to our host Sweden and IAEA. The development of nuclear science and technology and the peaceful uses of nuclear energy is one of the greatest achievements of the mankind in the 20. century. The development and progress of nuclear technology, from application of fission energy to the exploration of fusion energy, embodies the mankind's expectation to the future. It will be the major energy of final settlement of the issue of global sustainable development. The safe and effective treatment and disposal of nuclear waste are of vital importance to the peaceful uses of nuclear energy and technology. The most dangerous and long-lived waste has to be contained and isolated from the human living environment. Construction of geologic repository in appropriate geological formation for radioactive waste disposal is being accepted as a suitable solution and being studied widely. In the International Conference on Geological Repositories held in Denver, U.S.A., in November 1999, senior governmental representatives from more than 20 countries stated related policies and decisions of their respective countries, which caught world-wide attention. I am convinced that this conference, an event about geologic repository following the Denver conference, will produce positive results for the safe and effective disposal of nuclear waste. Now I would like to take this opportunity to brief you on China's current situation and perspectives of geologic disposal of high-level radioactive waste. (author)

Integration of crosswell seismic data for simulating porosity in a heterogeneous carbonate aquifer

Science.gov (United States)

Emery, Xavier; Parra, Jorge

2013-11-01

A challenge for the geostatistical simulation of subsurface properties in mining, petroleum and groundwater applications is the integration of well logs and seismic measurements, which can provide information on geological heterogeneities at a wide range of scales. This paper presents a case study conducted at the Port Mayaca aquifer, located in western Martin County, Florida, in which it is of interest to simulate porosity, based on porosity logs at two wells and high-resolution crosswell seismic measurements of P-wave impedance. To this end, porosity and impedance are transformed into cross-correlated Gaussian random fields, using local transformations. The model parameters (transformation functions, mean values and correlation structure of the transformed fields) are inferred and checked against the data. Multiple realizations of porosity can then be constructed conditionally to the impedance information in the interwell region, which allow identifying one low-porosity structure and two to three flow units that connect the two wells, mapping heterogeneities within these units and visually assessing fluid paths in the aquifer. In particular, the results suggest that the paths in the lower flow units, formed by a network of heterogeneous conduits, are not as smooth as in the upper flow unit.

Is high-resolution inverse characterization of heterogeneous river bed hydraulic conductivities needed and possible?

Directory of Open Access Journals (Sweden)

W. Kurtz

2013-10-01

Full Text Available River–aquifer exchange fluxes influence local and regional water balances and affect groundwater and river water quality and quantity. Unfortunately, river–aquifer exchange fluxes tend to be strongly spatially variable, and it is an open research question to which degree river bed heterogeneity has to be represented in a model in order to achieve reliable estimates of river–aquifer exchange fluxes. This research question is addressed in this paper with the help of synthetic simulation experiments, which mimic the Limmat aquifer in Zurich (Switzerland, where river–aquifer exchange fluxes and groundwater management activities play an important role. The solution of the unsaturated–saturated subsurface hydrological flow problem including river–aquifer interaction is calculated for ten different synthetic realities where the strongly heterogeneous river bed hydraulic conductivities (L are perfectly known. Hydraulic head data (100 in the default scenario are sampled from the synthetic realities. In subsequent data assimilation experiments, where L is unknown now, the hydraulic head data are used as conditioning information, with the help of the ensemble Kalman filter (EnKF. For each of the ten synthetic realities, four different ensembles of L are tested in the experiments with EnKF; one ensemble estimates high-resolution L fields with different L values for each element, and the other three ensembles estimate effective L values for 5, 3 or 2 zones. The calibration of higher-resolution L fields (i.e. fully heterogeneous or 5 zones gives better results than the calibration of L for only 3 or 2 zones in terms of reproduction of states, stream–aquifer exchange fluxes and parameters. Effective L for a limited number of zones cannot always reproduce the true states and fluxes well and results in biased estimates of net exchange fluxes between aquifer and stream. Also in case only 10 head data are used for conditioning, the high

Numerical investigation of high level nuclear waste disposal in deep anisotropic geologic repositories

KAUST Repository

Salama, Amgad; El Amin, Mohamed F.; Sun, Shuyu

2015-01-01

One of the techniques that have been proposed to dispose high level nuclear waste (HLW) has been to bury them in deep geologic formations, which offer relatively enough space to accommodate the large volume of HLW accumulated over the years since

Submarine fan reservoir architecture and heterogeneity influence on hard-to-recover reserves. Achimov Fm

International Nuclear Information System (INIS)

Kondratyev, A; Rukavishnikov, V; Maksyutin, K; Shakirzyanov, L

2015-01-01

Due to the fact that simulation model calculation is the basic method used for estimating the efficiency of a development strategy, it is necessary to design geological and simulation models within which reservoir properties and heterogeneity are defined. In addition, the estimation of the influence of various kinds of geological uncertainties on reservoir properties will allow defining a more effective development strategy. The Achimov formation of the Vingapur oil field was considered in the current study. The northern part of the field is now quite attractive for the development of this formation. The goal of this paper was the complex investigation of petrophysical properties to make a prognosis for the field and assess the effect of geologic uncertainties on production. The first step implied studying the western part of the field where core data are available, the next stage was developing an algorithm to make a prognosis for properties and the geologic and reservoir simulation models were eventually constructed to study the effect of geologic uncertainties in the northern part. As the result of the sedimentary analysis, a model of deposition was defined within which structural elements were also determined. On the basis of wireline and core data analysis, the petrophysical model of the reservoir was build where the method of Rock Types identification using specific cut-off values for wireline logs was applied for the evaluations. In addition to this, the Hydraulic Flow unit approach was employed, which allowed estimating the less extensively explored areas of the field where core had not been retrieved from. Also, this paper provides the results of the seismic attribute analysis and calculations in order to characterize uncertainty in cumulative oil production under the influence of petrophysical and geological heterogeneity

Groundwater flow and heterogeneous discharge into a seepage lake

DEFF Research Database (Denmark)

Kazmierczak, Jolanta; Müller, Sascha; Nilsson, B.

2016-01-01

with the lake remained under seemingly steady state conditions across seasons, a high spatial and temporal heterogeneity in the discharge to the lake was observed. The results showed that part of the groundwater flowing from the west passes beneath the lake and discharges at the eastern shore, where groundwater......Groundwater discharge into a seepage lake was investigated by combining flux measurements, hydrochemical tracers, geological information, and a telescopic modeling approach using first two-dimensional (2-D) regional then 2-D local flow and flow path models. Discharge measurements and hydrochemical...... tracers supplement each other. Discharge measurements yield flux estimates but rarely provide information about the origin and flow path of the water. Hydrochemical tracers may reveal the origin and flow path of the water but rarely provide any information about the flux. While aquifer interacting...

Rapidly reconfigurable high-fidelity optical arbitrary waveform generation in heterogeneous photonic integrated circuits.

Science.gov (United States)

Feng, Shaoqi; Qin, Chuan; Shang, Kuanping; Pathak, Shibnath; Lai, Weicheng; Guan, Binbin; Clements, Matthew; Su, Tiehui; Liu, Guangyao; Lu, Hongbo; Scott, Ryan P; Ben Yoo, S J

2017-04-17

This paper demonstrates rapidly reconfigurable, high-fidelity optical arbitrary waveform generation (OAWG) in a heterogeneous photonic integrated circuit (PIC). The heterogeneous PIC combines advantages of high-speed indium phosphide (InP) modulators and low-loss, high-contrast silicon nitride (Si3N4) arrayed waveguide gratings (AWGs) so that high-fidelity optical waveform syntheses with rapid waveform updates are possible. The generated optical waveforms spanned a 160 GHz spectral bandwidth starting from an optical frequency comb consisting of eight comb lines separated by 20 GHz channel spacing. The Error Vector Magnitude (EVM) values of the generated waveforms were approximately 16.4%. The OAWG module can rapidly and arbitrarily reconfigure waveforms upon every pulse arriving at 2 ns repetition time. The result of this work indicates the feasibility of truly dynamic optical arbitrary waveform generation where the reconfiguration rate or the modulator bandwidth must exceed the channel spacing of the AWG and the optical frequency comb.

Geological disposal of high-level radioactive wastes. Historical perspective and contemporary issues

International Nuclear Information System (INIS)

Ahn, Joonhong

2013-01-01

The contemporary concept on the geological disposal of radioactive wastes, the position of Japan in the world stream of geological disposal, and the ideal aspect of the Japanese geological disposal after the Fukushima accident are described. (M.H.)

Internal fracture heterogeneity in discrete fracture network modelling: Effect of correlation length and textures with connected and disconnected permeability field

Science.gov (United States)

Frampton, A.; Hyman, J.; Zou, L.

2017-12-01

Analysing flow and transport in sparsely fractured media is important for understanding how crystalline bedrock environments function as barriers to transport of contaminants, with important applications towards subsurface repositories for storage of spent nuclear fuel. Crystalline bedrocks are particularly favourable due to their geological stability, low advective flow and strong hydrogeochemical retention properties, which can delay transport of radionuclides, allowing decay to limit release to the biosphere. There are however many challenges involved in quantifying and modelling subsurface flow and transport in fractured media, largely due to geological complexity and heterogeneity, where the interplay between advective and dispersive flow strongly impacts both inert and reactive transport. A key to modelling transport in a Lagrangian framework involves quantifying pathway travel times and the hydrodynamic control of retention, and both these quantities strongly depend on heterogeneity of the fracture network at different scales. In this contribution, we present recent analysis of flow and transport considering fracture networks with single-fracture heterogeneity described by different multivariate normal distributions. A coherent triad of fields with identical correlation length and variance are created but which greatly differ in structure, corresponding to textures with well-connected low, medium and high permeability structures. Through numerical modelling of multiple scales in a stochastic setting we quantify the relative impact of texture type and correlation length against network topological measures, and identify key thresholds for cases where flow dispersion is controlled by single-fracture heterogeneity versus network-scale heterogeneity. This is achieved by using a recently developed novel numerical discrete fracture network model. Furthermore, we highlight enhanced flow channelling for cases where correlation structure continues across

Coupled Geomechanical-Flow Assessment of CO2 Leakage through Heterogeneous Caprock during CCS

Directory of Open Access Journals (Sweden)

Guan Woo Kim

2018-01-01

Full Text Available The viability of carbon capture sequestration (CCS is dependent on the secure storage of CO2 in subsurface geologic formations. Geomechanical failure of caprock is one of the main reasons of CO2 leakage from the storage formations. Through comprehensive assessment on the petrophysical and geomechanical heterogeneities of caprock, it is possible to predict the risk of unexpected caprock failure. To describe the fracture reactivation, the modified Barton–Bandis model is applied. In order to generate hydro-geomechanically heterogeneous fields, the negative correlation between porosity and Young’s modulus/Poisson’s ratio is applied. In comparison with the homogeneous model, effects of heterogeneity are examined in terms of vertical deformation and the amount of leaked CO2. To compare the effects of heterogeneity, heterogeneous models for both geomechanical and petrophysical properties in coupled simulation are designed. After 10-year injection with petrophysically heterogeneous and geomechanically homogeneous caprock, CO2 leakage is larger than that of the homogeneous model. In contrast, heterogeneity of geomechanical properties is shown to mitigate additional escape of CO2. Vertical displacement of every heterogeneous model is larger than homogeneous model. The model with compressive tectonic stress shows much more stable trapping with heterogeneous caprock, but there is possibility of rapid leakage after homogeneous caprock failure.

Mineralogical Diversity and Geology of Humboldt Crater Derived Using Moon Mineralogy Mapper Data

Science.gov (United States)

Martinot, M.; Besse, S.; Flahaut, J.; Quantin-Nataf, C.; Lozac'h, L.; van Westrenen, W.

2018-02-01

Moon Mineralogy Mapper (M3) spectroscopic data and high-resolution imagery data sets were used to study the mineralogy and geology of the 207 km diameter Humboldt crater. Analyses of M3 data, using a custom-made method for M3 spectra continuum removal and spectral parameters calculation, reveal multiple pure crystalline plagioclase detections within the Humboldt crater central peak complex, hinting at its crustal origin. However, olivine, spinel, and glass are observed in the crater walls and rims, suggesting these minerals derive from shallower levels than the plagioclase of the central peak complex. High-calcium pyroxenes are detected in association with volcanic deposits emplaced on the crater's floor. Geologic mapping was performed, and the age of Humboldt crater's units was estimated from crater counts. Results suggest that volcanic activity within this floor-fractured crater spanned over a billion years. The felsic mineralogy of the central peak complex region, which presumably excavated deeper material, and the shallow mafic minerals (olivine and spinel) detected in Humboldt crater walls and rim are not in accordance with the general view of the structure of the lunar crust. Our observations can be explained by the presence of a mafic pluton emplaced in the anorthositic crust prior to the Humboldt-forming impact event. Alternatively, the excavation of Australe basin ejecta could explain the observed mineralogical detections. This highlights the importance of detailed combined mineralogical and geological remote sensing studies to assess the heterogeneity of the lunar crust.

Mineralogical Diversity and Geology of Humboldt Crater Derived Using Moon Mineralogy Mapper Data.

Science.gov (United States)

Martinot, M; Besse, S; Flahaut, J; Quantin-Nataf, C; Lozac'h, L; van Westrenen, W

2018-02-01

Moon Mineralogy Mapper (M 3 ) spectroscopic data and high-resolution imagery data sets were used to study the mineralogy and geology of the 207 km diameter Humboldt crater. Analyses of M 3 data, using a custom-made method for M 3 spectra continuum removal and spectral parameters calculation, reveal multiple pure crystalline plagioclase detections within the Humboldt crater central peak complex, hinting at its crustal origin. However, olivine, spinel, and glass are observed in the crater walls and rims, suggesting these minerals derive from shallower levels than the plagioclase of the central peak complex. High-calcium pyroxenes are detected in association with volcanic deposits emplaced on the crater's floor. Geologic mapping was performed, and the age of Humboldt crater's units was estimated from crater counts. Results suggest that volcanic activity within this floor-fractured crater spanned over a billion years. The felsic mineralogy of the central peak complex region, which presumably excavated deeper material, and the shallow mafic minerals (olivine and spinel) detected in Humboldt crater walls and rim are not in accordance with the general view of the structure of the lunar crust. Our observations can be explained by the presence of a mafic pluton emplaced in the anorthositic crust prior to the Humboldt-forming impact event. Alternatively, the excavation of Australe basin ejecta could explain the observed mineralogical detections. This highlights the importance of detailed combined mineralogical and geological remote sensing studies to assess the heterogeneity of the lunar crust.

Practical considerations of reservoir heterogeneities on SAGD projects

Energy Technology Data Exchange (ETDEWEB)

Baker, R.; Fong, C.; Li, T. [Epic Consulting Services Ltd., Calgary, AB (Canada); Bowes, C.; Toews, M. [Calgary Univ., AB (Canada)

2008-10-15

Significant emphasis has been placed on developing cost-effective strategies for the production of large heavy oil and bitumen reserves located in western Canada and around the world. An effective method that has been proven to be effective in this regard is steam-assisted gravity drainage (SAGD). However, determining the optimum and cost-effective strategy is a challenge to any SAGD reservoir. Average rock quality and reservoir heterogeneities have a significant impact on steam chamber development and the overall volumetric sweep. As well, the approach to SAGD simulation varies as heterogeneity changes. This paper examined two well pairs with different degrees of heterogeneity in the Surmont pilot project. The paper also addressed potential geological risk through analogy and the amount of heterogeneity that must be accounted for when developing a representative simulation. The paper provided background information on the Surmont pilot project, which consists of three horizontal SAGD well pairs in the Athabasca oil sands of northeast Alberta. The reservoir simulation model was then described. Results and conclusions were offered. It was concluded that careful production controls and strategy must be applied particular to the reservoir to ensure that the SAGD well pairs were capable of draining the mobilized oil. 5 refs., 1 tab., 25 figs.

OneGeology-Europe: architecture, portal and web services to provide a European geological map

Science.gov (United States)

Tellez-Arenas, Agnès.; Serrano, Jean-Jacques; Tertre, François; Laxton, John

2010-05-01

OneGeology-Europe is a large ambitious project to make geological spatial data further known and accessible. The OneGeology-Europe project develops an integrated system of data to create and make accessible for the first time through the internet the geological map of the whole of Europe. The architecture implemented by the project is web services oriented, based on the OGC standards: the geological map is not a centralized database but is composed by several web services, each of them hosted by a European country involved in the project. Since geological data are elaborated differently from country to country, they are difficult to share. OneGeology-Europe, while providing more detailed and complete information, will foster even beyond the geological community an easier exchange of data within Europe and globally. This implies an important work regarding the harmonization of the data, both model and the content. OneGeology-Europe is characterised by the high technological capacity of the EU Member States, and has the final goal to achieve the harmonisation of European geological survey data according to common standards. As a direct consequence Europe will make a further step in terms of innovation and information dissemination, continuing to play a world leading role in the development of geosciences information. The scope of the common harmonized data model was defined primarily by the requirements of the geological map of Europe, but in addition users were consulted and the requirements of both INSPIRE and ‘high-resolution' geological maps were considered. The data model is based on GeoSciML, developed since 2006 by a group of Geological Surveys. The data providers involved in the project implemented a new component that allows the web services to deliver the geological map expressed into GeoSciML. In order to capture the information describing the geological units of the map of Europe the scope of the data model needs to include lithology; age; genesis and

Maximizing reservoir exposure with proactive well placement in high geological complexity field of Venezuelan Orinoco Belt

Energy Technology Data Exchange (ETDEWEB)

Castaneda, Luis; Leon, Maryesther; Meunier, Antoine [Schlumberger, Caracas (Venezuela); Lara, Manuel; Herrera, Yoanna; Granado, Miguel [Petrolera Indovenezolana S.A. (PIV), El Tigre (Venezuela)

2012-07-01

In 2010, Petrolera Indovenezolana S.A. (PIV), a joint venture between Corporacion Venezolana del Petroleo (CVP) and the Indian company ONGC Videsh Limited (OVL), started planning for two horizontal wells in the Norte Zuata (San Cristobal) field in the Orinoco belt of eastern Venezuela. The focus for this campaign was to evaluate the productivity of horizontal wells in thin sands and avoid areas of complex geology because of the high uncertainty in the structural behavior, applying technology that provided absolute control of the drilling process into the Oficina formation. Within the Oficina formation, thin sand reservoirs with variations in thickness and dip, geologically facies changes and sub seismic faults presented the main challenge to geosteering a horizontal well. Because the project faced high geological uncertainties, a pilot hole was drilled as the first stage in the first well to verify the structural levels and the continuity of the sand bodies. To achieve the above challenges, the combination of a rotary steerable system (RSS) 'point-the-bit' and a deep azimuthal electromagnetic resistivity tool (DAEMR) was used. The measurements provided accurate information to the well-placement engineers for proactive decisions in real time, mitigating the possible loss of the target by these geologic uncertainties. High-quality and valuable data for real time geological model update were the expected results obtained from the effort made by PIV in the Norte Zuata (San Cristobal) field, and the data showed the oil-producing potential of one of the main reservoir (Sand F,G). This application of high-tier technologies demonstrated that drilling and data measurements can be improved and optimized to yield added value for reservoir development and 100% net to gross (NTG) targets. This reduces operational cost, makes it possible to drill in the right place the first time, and pushes forward the limit of the achievable in terms of reservoir exposure. (author)

Laser-Induced Fluorescence Detection in High-Throughput Screening of Heterogeneous Catalysts and Single Cells Analysis

Energy Technology Data Exchange (ETDEWEB)

Su, Hui [Iowa State Univ., Ames, IA (United States)

2001-01-01

Laser-induced fluorescence detection is one of the most sensitive detection techniques and it has found enormous applications in various areas. The purpose of this research was to develop detection approaches based on laser-induced fluorescence detection in two different areas, heterogeneous catalysts screening and single cell study. First, we introduced laser-induced imaging (LIFI) as a high-throughput screening technique for heterogeneous catalysts to explore the use of this high-throughput screening technique in discovery and study of various heterogeneous catalyst systems. This scheme is based on the fact that the creation or the destruction of chemical bonds alters the fluorescence properties of suitably designed molecules. By irradiating the region immediately above the catalytic surface with a laser, the fluorescence intensity of a selected product or reactant can be imaged by a charge-coupled device (CCD) camera to follow the catalytic activity as a function of time and space. By screening the catalytic activity of vanadium pentoxide catalysts in oxidation of naphthalene, we demonstrated LIFI has good detection performance and the spatial and temporal resolution needed for high-throughput screening of heterogeneous catalysts. The sample packing density can reach up to 250 x 250 subunits/cm₂ for 40-μm wells. This experimental set-up also can screen solid catalysts via near infrared thermography detection.

Laser-Induced Fluorescence Detection in High-Throughput Screening of Heterogeneous Catalysts and Single Cells Analysis

International Nuclear Information System (INIS)

Hui Su

2001-01-01

Laser-induced fluorescence detection is one of the most sensitive detection techniques and it has found enormous applications in various areas. The purpose of this research was to develop detection approaches based on laser-induced fluorescence detection in two different areas, heterogeneous catalysts screening and single cell study. First, we introduced laser-induced imaging (LIFI) as a high-throughput screening technique for heterogeneous catalysts to explore the use of this high-throughput screening technique in discovery and study of various heterogeneous catalyst systems. This scheme is based on the fact that the creation or the destruction of chemical bonds alters the fluorescence properties of suitably designed molecules. By irradiating the region immediately above the catalytic surface with a laser, the fluorescence intensity of a selected product or reactant can be imaged by a charge-coupled device (CCD) camera to follow the catalytic activity as a function of time and space. By screening the catalytic activity of vanadium pentoxide catalysts in oxidation of naphthalene, we demonstrated LIFI has good detection performance and the spatial and temporal resolution needed for high-throughput screening of heterogeneous catalysts. The sample packing density can reach up to 250 x 250 subunits/cm(sub 2) for 40-(micro)m wells. This experimental set-up also can screen solid catalysts via near infrared thermography detection

Geological hazard monitoring system in Georgia

Science.gov (United States)

Gaprindashvili, George

2017-04-01

Georgia belongs to one of world's most complex mountainous regions according to the scale and frequency of Geological processes and damage caused to population, farmlands, and Infrastructure facilities. Geological hazards (landslide, debrisflow/mudflow, rockfall, erosion and etc.) are affecting many populated areas, agricultural fields, roads, oil and gas pipes, high-voltage electric power transmission towers, hydraulic structures, and tourist complexes. Landslides occur almost in all geomorphological zones, resulting in wide differentiation in the failure types and mechanisms and in the size-frequency distribution. In Georgia, geological hazards triggered by: 1. Activation of highly intense earthquakes; 2. Meteorological events provoking the disaster processes on the background of global climatic change; 3. Large-scale Human impact on the environment. The prediction and monitoring of Geological Hazards is a very wide theme, which involves different researchers from different spheres. Geological hazard monitoring is essential to prevent and mitigate these hazards. In past years in Georgia several monitoring system, such as Ground-based geodetic techniques, Debrisflow Early Warning System (EWS) were installed on high sensitive landslide and debrisflow areas. This work presents description of Geological hazard monitoring system in Georgia.

High-density multicore fiber with heterogeneous core arrangement

DEFF Research Database (Denmark)

Amma, Y.; Sasaki, Y.; Takenaga, K.

2015-01-01

A 30-core fiber with heterogeneous cores that achieved large spatial multiplicity and low crosstalk of less than −40 dB at 100 km was demonstrated. The correlation lengths were estimated to be more than 1 m.......A 30-core fiber with heterogeneous cores that achieved large spatial multiplicity and low crosstalk of less than −40 dB at 100 km was demonstrated. The correlation lengths were estimated to be more than 1 m....

High-Efficient Parallel CAVLC Encoders on Heterogeneous Multicore Architectures

Directory of Open Access Journals (Sweden)

H. Y. Su

2012-04-01

Full Text Available This article presents two high-efficient parallel realizations of the context-based adaptive variable length coding (CAVLC based on heterogeneous multicore processors. By optimizing the architecture of the CAVLC encoder, three kinds of dependences are eliminated or weaken, including the context-based data dependence, the memory accessing dependence and the control dependence. The CAVLC pipeline is divided into three stages: two scans, coding, and lag packing, and be implemented on two typical heterogeneous multicore architectures. One is a block-based SIMD parallel CAVLC encoder on multicore stream processor STORM. The other is a component-oriented SIMT parallel encoder on massively parallel architecture GPU. Both of them exploited rich data-level parallelism. Experiments results show that compared with the CPU version, more than 70 times of speedup can be obtained for STORM and over 50 times for GPU. The implementation of encoder on STORM can make a real-time processing for 1080p @30fps and GPU-based version can satisfy the requirements for 720p real-time encoding. The throughput of the presented CAVLC encoders is more than 10 times higher than that of published software encoders on DSP and multicore platforms.

Albedo Neutron Dosimetry in a Deep Geological Disposal Repository for High-Level Nuclear Waste.

Science.gov (United States)

Pang, Bo; Becker, Frank

2017-04-28

Albedo neutron dosemeter is the German official personal neutron dosemeter in mixed radiation fields where neutrons contribute to personal dose. In deep geological repositories for high-level nuclear waste, where neutrons can dominate the radiation field, it is of interest to investigate the performance of albedo neutron dosemeter in such facilities. In this study, the deep geological repository is represented by a shielding cask loaded with spent nuclear fuel placed inside a rock salt emplacement drift. Due to the backscattering of neutrons in the drift, issues concerning calibration of the dosemeter arise. Field-specific calibration of the albedo neutron dosemeter was hence performed with Monte Carlo simulations. In order to assess the applicability of the albedo neutron dosemeter in a deep geological repository over a long time scale, spent nuclear fuel with different ages of 50, 100 and 500 years were investigated. It was found out, that the neutron radiation field in a deep geological repository can be assigned to the application area 'N1' of the albedo neutron dosemeter, which is typical in reactors and accelerators with heavy shielding. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Geological and geotechnical limitations of radioactive waste retrievability in geologic disposals

Energy Technology Data Exchange (ETDEWEB)

Stahlmann, Joachim; Leon-Vargas, Rocio; Mintzlaff, Volker; Treidler, Ann-Kathrin [TU Braunschweig (Germany). Inst. for Soil Mechanics and Foundation Engineering

2015-07-01

The capability of retrieving radioactive waste emplaced in deep geological formations is nowadays in discussion in many countries. Based on the storage of high-level radioactive waste (HAW) in deep geological repositories there is a number of possible scenarios for their retrieval. Measurements for an improved retrieving capability may impact on the geotechnical and geological barriers, e.g. keeping open the access drifts for a long period of time can result in a bigger evacuation damage zone (EDZ) in the host rock which implies potential flow paths for ground water. Nevertheless, to limit the possible scenarios associated to the retrieval implementation, it is necessary to take in consideration which criteria will be used for an efficient monitoring program, while clearly determining the performance reliability of the geotechnical barriers. In addition, the integrity of the host rock as geological barrier has to be verified. Therefore, it is important to evaluate different design solutions and the most appropriate measurement methods to improve the retrievability process of wastes from a geological repository. A short presentation of the host rocks is given is this paper.

Interfaces between transport and geological disposal systems for high level radioactive waste and spent nuclear fuel

International Nuclear Information System (INIS)

1994-09-01

This document is an IAEA publication which identifies and discusses the interfaces and the interface requirements between high level waste, the waste transport system used for carriage of the waste to the disposal facility, and the high level waste disposal facility. The development of this document was prompted in part by the initiatives in various Member States to select, characterize and design the facilities for potential high level waste geological repositories. These initiatives have progressed to the point where an international document would be useful in calling attention to the need for establishing, in a systematic way, interfaces and interface requirements between the transport systems to be used and the waste disposal packages and geological repository. Refs, figs and tabs

Spatial and temporal heterogeneity in high-grade serous ovarian cancer: a phylogenetic analysis.

Directory of Open Access Journals (Sweden)

Roland F Schwarz

2015-02-01

Full Text Available The major clinical challenge in the treatment of high-grade serous ovarian cancer (HGSOC is the development of progressive resistance to platinum-based chemotherapy. The objective of this study was to determine whether intra-tumour genetic heterogeneity resulting from clonal evolution and the emergence of subclonal tumour populations in HGSOC was associated with the development of resistant disease.Evolutionary inference and phylogenetic quantification of heterogeneity was performed using the MEDICC algorithm on high-resolution whole genome copy number profiles and selected genome-wide sequencing of 135 spatially and temporally separated samples from 14 patients with HGSOC who received platinum-based chemotherapy. Samples were obtained from the clinical CTCR-OV03/04 studies, and patients were enrolled between 20 July 2007 and 22 October 2009. Median follow-up of the cohort was 31 mo (interquartile range 22-46 mo, censored after 26 October 2013. Outcome measures were overall survival (OS and progression-free survival (PFS. There were marked differences in the degree of clonal expansion (CE between patients (median 0.74, interquartile range 0.66-1.15, and dichotimization by median CE showed worse survival in CE-high cases (PFS 12.7 versus 10.1 mo, p = 0.009; OS 42.6 versus 23.5 mo, p = 0.003. Bootstrap analysis with resampling showed that the 95% confidence intervals for the hazard ratios for PFS and OS in the CE-high group were greater than 1.0. These data support a relationship between heterogeneity and survival but do not precisely determine its effect size. Relapsed tissue was available for two patients in the CE-high group, and phylogenetic analysis showed that the prevalent clonal population at clinical recurrence arose from early divergence events. A subclonal population marked by a NF1 deletion showed a progressive increase in tumour allele fraction during chemotherapy.This study demonstrates that quantitative measures of intra

Retrievability of high-level nuclear waste from geologic repositories - Regulatory and rock mechanics/design considerations

International Nuclear Information System (INIS)

Tanious, N.S.; Nataraja, M.S.; Daemen, J.J.K.

1987-01-01

Retrievability of nuclear waste from high-level geologic repositories is one of the performance objectives identified in 10CFR60 (Code of Federal Regulations, 1985). 10CFR60.111 states that the geologic repository operations area shall be designed to preserve the option of waste retrieval. In designing the repository operations area, rock mechanics considerations play a major role especially in evaluating the feasibility of retrieval operations. This paper discusses generic considerations affecting retrievability as they relate to repository design, construction, and operation, with emphasis on regulatory and rock mechanics aspects

Engineering Geology | Alaska Division of Geological & Geophysical Surveys

Science.gov (United States)

Alaska's Mineral Industry Reports AKGeology.info Rare Earth Elements WebGeochem Engineering Geology Alaska content Engineering Geology Additional information Engineering Geology Posters and Presentations Alaska Alaska MAPTEACH Tsunami Inundation Mapping Engineering Geology Staff Projects The Engineering Geology

Field scale heterogeneity of redox conditions in till-upscaling to a catchment nitrate model

DEFF Research Database (Denmark)

Hansen, J.R.; Erntsen, V.; Refsgaard, J.C.

2008-01-01

Point scale studies in different settings of glacial geology show a large local variation of redox conditions. There is a need to develop an upscaling methodology for catchment scale models. This paper describes a study of field-scale heterogeneity of redox-interfaces in a till aquitard within an...

Thermal inertia and surface heterogeneity on Mars

Science.gov (United States)

Putzig, Nathaniel E.

Thermal inertia derived from temperature observations is critical for understanding surface geology and assessing potential landing sites on Mars. Derivation methods generally assume uniform surface properties for any given observation. Consequently, horizontal heterogeneity and near-surface layering may yield apparent thermal inertia that varies with time of day and season. To evaluate the effects of horizontal heterogeneity, I modeled the thermal behavior of surfaces containing idealized material mixtures (dust, sand, duricrust, and rocks) and differing slope facets. These surfaces exhibit diurnal and seasonal variability in apparent thermal inertia of several 100 tiu, 1 even for components with moderately contrasting thermal properties. To isolate surface effects on the derived thermal inertia of Mars, I mapped inter- annual and seasonal changes in albedo and atmospheric dust opacity, accounting for their effects in a modified derivation algorithm. Global analysis of three Mars years of MGS-TES 2 data reveals diurnal and seasonal variations of ~200 tiu in the mid-latitudes and 600 tiu or greater in the polar regions. Correlation of TES results and modeled apparent thermal inertia of heterogeneous surfaces indicates pervasive surface heterogeneity on Mars. At TES resolution, the near-surface thermal response is broadly dominated by layering and is consistent with the presence of duricrusts over fines in the mid-latitudes and dry soils over ground ice in the polar regions. Horizontal surface mixtures also play a role and may dominate at higher resolution. In general, thermal inertia obtained from single observations or annually averaged maps may misrepresent surface properties. In lieu of a robust heterogeneous- surface derivation technique, repeat coverage can be used together with forward-modeling results to constrain the near-surface heterogeneity of Mars. 1 tiu == J m -2 K -1 s - 2 Mars Global Surveyor Thermal Emission Spectrometer

Numerical investigation of high level nuclear waste disposal in deep anisotropic geologic repositories

KAUST Repository

Salama, Amgad

2015-11-01

One of the techniques that have been proposed to dispose high level nuclear waste (HLW) has been to bury them in deep geologic formations, which offer relatively enough space to accommodate the large volume of HLW accumulated over the years since the dawn of nuclear era. Albeit the relatively large number of research works that have been conducted to investigate temperature distribution surrounding waste canisters, they all abide to consider the host formations as homogeneous and isotropic. While this could be the case in some subsurface settings, in most cases, this is not true. In other words, subsurface formations are, in most cases, inherently anisotropic and heterogeneous. In this research, we show that even a slight difference in anisotropy of thermal conductivity of host rock with direction could have interesting effects on temperature fields. We investigate the effect of anisotropy angle (the angle the principal direction of anisotropy is making with the coordinate system) on the temperature field as well as on the maximum temperature attained in different barrier systems. This includes 0°, 30°, 45°, 60°, and 90°in addition to the isotropic case as a reference. We also consider the effect of anisotropy ratio (the ratio between the principal direction anisotropies) on the temperature fields and maximum temperature history. This includes ratios ranging between 1.5 and 4. Interesting patterns of temperature fields and profiles are obtained. It is found that the temperature contours are aligned more towards the principal direction of anisotropy. Furthermore the peak temperature in the buffer zone is found to be larger the smaller the anisotropy angle and vice versa. © 2015 Elsevier Ltd. All rights reserved.

Changing the scale of hydrogeophysical aquifer heterogeneity characterization

Science.gov (United States)

Paradis, Daniel; Tremblay, Laurie; Ruggeri, Paolo; Brunet, Patrick; Fabien-Ouellet, Gabriel; Gloaguen, Erwan; Holliger, Klaus; Irving, James; Molson, John; Lefebvre, Rene

2015-04-01

Contaminant remediation and management require the quantitative predictive capabilities of groundwater flow and mass transport numerical models. Such models have to encompass source zones and receptors, and thus typically cover several square kilometers. To predict the path and fate of contaminant plumes, these models have to represent the heterogeneous distribution of hydraulic conductivity (K). However, hydrogeophysics has generally been used to image relatively restricted areas of the subsurface (small fractions of km2), so there is a need for approaches defining heterogeneity at larger scales and providing data to constrain conceptual and numerical models of aquifer systems. This communication describes a workflow defining aquifer heterogeneity that was applied over a 12 km2 sub-watershed surrounding a decommissioned landfill emitting landfill leachate. The aquifer is a shallow, 10 to 20 m thick, highly heterogeneous and anisotropic assemblage of littoral sand and silt. Field work involved the acquisition of a broad range of data: geological, hydraulic, geophysical, and geochemical. The emphasis was put on high resolution and continuous hydrogeophysical data, the use of direct-push fully-screened wells and the acquisition of targeted high-resolution hydraulic data covering the range of observed aquifer materials. The main methods were: 1) surface geophysics (ground-penetrating radar and electrical resistivity); 2) direct-push operations with a geotechnical drilling rig (cone penetration tests with soil moisture resistivity CPT/SMR; full-screen well installation); and 3) borehole operations, including high-resolution hydraulic tests and geochemical sampling. New methods were developed to acquire high vertical resolution hydraulic data in direct-push wells, including both vertical and horizontal K (Kv and Kh). Various data integration approaches were used to represent aquifer properties in 1D, 2D and 3D. Using relevant vector machines (RVM), the mechanical and

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

Energy Technology Data Exchange (ETDEWEB)

Hamilton, D.S.; Raeuchle, S.K.; Holtz, M.H. [Bureau of Economic Geology, Austin, TX (United States)] [and others

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.

A constrained Delaunay discretization method for adaptively meshing highly discontinuous geological media

Science.gov (United States)

Wang, Yang; Ma, Guowei; Ren, Feng; Li, Tuo

2017-12-01

A constrained Delaunay discretization method is developed to generate high-quality doubly adaptive meshes of highly discontinuous geological media. Complex features such as three-dimensional discrete fracture networks (DFNs), tunnels, shafts, slopes, boreholes, water curtains, and drainage systems are taken into account in the mesh generation. The constrained Delaunay triangulation method is used to create adaptive triangular elements on planar fractures. Persson's algorithm (Persson, 2005), based on an analogy between triangular elements and spring networks, is enriched to automatically discretize a planar fracture into mesh points with varying density and smooth-quality gradient. The triangulated planar fractures are treated as planar straight-line graphs (PSLGs) to construct piecewise-linear complex (PLC) for constrained Delaunay tetrahedralization. This guarantees the doubly adaptive characteristic of the resulted mesh: the mesh is adaptive not only along fractures but also in space. The quality of elements is compared with the results from an existing method. It is verified that the present method can generate smoother elements and a better distribution of element aspect ratios. Two numerical simulations are implemented to demonstrate that the present method can be applied to various simulations of complex geological media that contain a large number of discontinuities.

Natural setting of Japanese islands and geologic disposal of high-level waste

International Nuclear Information System (INIS)

Koide, Hitoshi

1991-01-01

The Japanese islands are a combination of arcuate islands along boundaries between four major plates: Eurasia, North America, Pacific and Philippine Sea plates. The interaction among the four plates formed complex geological structures which are basically patchworks of small blocks of land and sea-floor sediments piled up by the subduction of oceanic plates along the margin of the Eurasia continent. Although frequent earthquakes and volcanic eruptions clearly indicate active crustal deformation, the distribution of active faults and volcanoes is localized regionally in the Japanese islands. Crustal displacement faster than 1 mm/year takes place only in restricted regions near plate boundaries or close to major active faults. Volcanic activity is absent in the region between the volcanic front and the subduction zone. The site selection is especially important in Japan. The scenarios for the long-term performance assessment of high-level waste disposal are discussed with special reference to the geological setting of Japan. The long-term prediction of tectonic disturbance, evaluation of faults and fractures in rocks and estimation of long-term water-rock interaction are key issues in the performance assessment of the high-level waste disposal in the Japanese islands. (author)

[Diagnostic imaging of high-grade astrocytoma: heterogeneity of clinical manifestation, image characteristics, and histopathological findings].

Science.gov (United States)

Okajima, Kaoru; Ohta, Yoshio

2012-10-01

Recent developments in diagnostic radiology, which have enabled accurate differential diagnoses of brain tumors, have been well described in the last three decades. MR and PET imaging can also provide information to predict histological grades and prognoses that might influence treatment strategies. However, high-grade astrocytomas consist of many different subtypes that are associated with different imaging and histological characteristics. Hemorrhage and necrosis results in a variety of imaging features, and infiltrative tumor growth entrapping normal neurons may cause different clinical manifestations. We reviewed patients with high-grade astrocytomas that showed various imaging characteristics, with special emphasis on initial symptoms and histological features. Clinicopathological characteristics of astrocytomas were also compared with other malignant tumors. Neurological deficits were not notable in patients with grade 3-4 astrocytomas when they showed infiltrative tumor growth, while brain metastases with compact cellular proliferation caused more neurological symptoms. Infiltrative tumors did not show any enhancing masses on MR imaging, but these tumors may show intratumor heterogeneity. Seizures were reported to be more frequent in low-grade glioma and in secondary glioblastoma. Tumor heterogeneity was also reported in molecular genetic profile, and investigators identified some subsets of astrocytomas. They investigated IHD1/2 mutation, EGFR amplification, TP53 mutation, Ki-67 index, etc. In summary, high-grade astrocytomas are not homogenous groups of tumors, and this is associated with the heterogeneity of clinical manifestation, image characteristics, and histopathological findings. Molecular studies may explain the tumor heterogeneity in the near future.

Constructing a Geology Ontology Using a Relational Database

Science.gov (United States)

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

Technical development for geological disposal of high-level radioactive wastes

International Nuclear Information System (INIS)

Asano, Hidekazu; Sugino, Hiroyuki; Kawakami, Susumu; Yamanaka, Yumiko

1997-01-01

Technical developments for geological disposal of high-level radioactive wastes materials research and design technique for engineered barriers (overpack and buffer material) were studied to evaluate more reliable disposal systems for high-level radioactive wastes. A lifetime prediction model for the maximum corrosion depth of carbon steel was developed. A preferable alloys evaluation method for crevice corrosion was established for titanium. Swelling pressure and water permeability of bentonite as a buffer material was measured, and coupled hydro-thermo-mechanical analysis code for bentonite was also studied. The CIP (cold isostatic pressing) method for monolithically formed buffer material was tested. A concept study on operation equipment for the disposal site was performed. Activities of microorganisms involved in underground performance were investigated. (author)

Synthesis of carbonate esters by carboxymethylation using NaAlO2 as a highly active heterogeneous catalyst

OpenAIRE

Ramesh, Sreerangappa; Indukuri, Kiran; Riant, Olivier; Debecker, Damien

2018-01-01

Sodium aluminate is presented as a highly active heterogeneous catalyst able to convert a range of alcohols into the corresponding mixed carbonate esters, in high yield and under green conditions. The reaction is carried out using dimethyl carbonate both as a reactant and solvent, at 90°C. Allylic, aliphatic and aromatic alcohols are converted in good yields. The solid catalyst is shown to be truly heterogeneous, resistant to leaching, and recyclable.

High-density biosynthetic fuels: the intersection of heterogeneous catalysis and metabolic engineering.

Science.gov (United States)

Harvey, Benjamin G; Meylemans, Heather A; Gough, Raina V; Quintana, Roxanne L; Garrison, Michael D; Bruno, Thomas J

2014-05-28

Biosynthetic valencene, premnaspirodiene, and natural caryophyllene were hydrogenated and evaluated as high performance fuels. The parent sesquiterpenes were then isomerized to complex mixtures of hydrocarbons with the heterogeneous acid catalyst Nafion SAC-13. High density fuels with net heats of combustion ranging from 133-141 000 Btu gal(-1), or up to 13% higher than commercial jet fuel could be generated by this approach. The products of caryophyllene isomerization were primarily tricyclic hydrocarbons which after hydrogenation increased the fuel density by 6%. The isomerization of valencene and premnaspirodiene also generated a variety of sesquiterpenes, but in both cases the dominant product was δ-selinene. Ab initio calculations were conducted to determine the total electronic energies for the reactants and products. In all cases the results were in excellent agreement with the experimental distribution of isomers. The cetane numbers for the sesquiterpane fuels ranged from 20-32 and were highly dependent on the isomer distribution. Specific distillation cuts may have the potential to act as high density diesel fuels, while use of these hydrocarbons as additives to jet fuel will increase the range and/or time of flight of aircraft. In addition to the ability to generate high performance renewable fuels, the powerful combination of metabolic engineering and heterogeneous catalysis will allow for the preparation of a variety of sesquiterpenes with potential for pharmaceutical, flavor, and fragrance applications.

Final Report: Optimal Model Complexity in Geological Carbon Sequestration: A Response Surface Uncertainty Analysis

Energy Technology Data Exchange (ETDEWEB)

Zhang, Ye [Univ. of Wyoming, Laramie, WY (United States)

2018-01-17

The critical component of a risk assessment study in evaluating GCS is an analysis of uncertainty in CO2 modeling. In such analyses, direct numerical simulation of CO2 flow and leakage requires many time-consuming model runs. Alternatively, analytical methods have been developed which allow fast and efficient estimation of CO2 storage and leakage, although restrictive assumptions on formation rock and fluid properties are employed. In this study, an intermediate approach is proposed based on the Design of Experiment and Response Surface methodology, which consists of using a limited number of numerical simulations to estimate a prediction outcome as a combination of the most influential uncertain site properties. The methodology can be implemented within a Monte Carlo framework to efficiently assess parameter and prediction uncertainty while honoring the accuracy of numerical simulations. The choice of the uncertain properties is flexible and can include geologic parameters that influence reservoir heterogeneity, engineering parameters that influence gas trapping and migration, and reactive parameters that influence the extent of fluid/rock reactions. The method was tested and verified on modeling long-term CO2 flow, non-isothermal heat transport, and CO2 dissolution storage by coupling two-phase flow with explicit miscibility calculation using an accurate equation of state that gives rise to convective mixing of formation brine variably saturated with CO2. All simulations were performed using three-dimensional high-resolution models including a target deep saline aquifer, overlying caprock, and a shallow aquifer. To evaluate the uncertainty in representing reservoir permeability, sediment hierarchy of a heterogeneous digital stratigraphy was mapped to create multiple irregularly shape stratigraphic models of decreasing geologic resolutions: heterogeneous (reference), lithofacies, depositional environment, and a (homogeneous) geologic formation. To ensure model

A state geological survey commitment to environmental geology - the Texas Bureau of Economic Geology

International Nuclear Information System (INIS)

Wermund, E.G.

1990-01-01

In several Texas environmental laws, the Bureau of Economic Geology is designated as a planning participant and review agency in the process of fulfilling environmental laws. Two examples are legislation on reclamation of surface mines and regulation of processing low level radioactive wastes. Also, the Bureau is the principal geological reviewer of all Environmental Assessments and Environmental Impact Statements which the Office of the Governor circulates for state review on all major developmental activities in Texas. The BEG continues its strong interest in environmental geology. In February 1988, it recommitted its Land Resources Laboratory, initiated in 1974, toward fulfilling needs of state, county, and city governments for consultation and research on environmental geologic problems. An editorial from another state geological survey would resemble the about description of texas work in environmental geology. State geological surveys have led federal agencies into many developments of environmental geology, complemented federal efforts in their evolution, and continued a strong commitment to the maintenance of a quality environment through innovative geologic studies

3D modeling of carbonates petro-acoustic heterogeneities

Science.gov (United States)

Baden, Dawin; Guglielmi, Yves; Saracco, Ginette; Marié, Lionel; Viseur, Sophie

2015-04-01

Characterizing carbonate reservoirs heterogeneity is a challenging issue for Oil & Gas Industry, CO2 sequestration and all kinds of fluid manipulations in natural reservoirs, due to the significant impact of heterogeneities on fluid flow and storage within the reservoir. Although large scale (> meter) heterogeneities such as layers petrophysical contrasts are well addressed by computing facies-based models, low scale (ultrasonic apparatus and using different sensors allowing acoustic characterization through a bandwidth varying from 50 to 500 kHz. Comprehensive measurements realized on each samples allowed statistical analyses of petro-acoustic properties such as attenuation, shear and longitudinal wave velocity. The cores properties (geological and acoustic facies) were modeled in 3D using photogrammetry and GOCAD geo-modeler. This method successfully allowed detecting and imaging in three dimensions differential diagenesis effects characterized by the occurrence of decimeter-scale diagenetic horizons in samples assumed to be homogeneous and/or different diagenetic sequences between shells filling and the packing matrix. We then discuss how small interfaces such as cracks, stylolithes and laminations which are also imaged may have guided these differential effects, considering that understanding the processes may be taken as an analogue to actual fluid drainage complexity in deep carbonate reservoir.

Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction

International Nuclear Information System (INIS)

R.A. Levich; J.S. Stuckless

2006-01-01

Yucca Mountain in Nevada represents the proposed solution to what has been a lengthy national effort to dispose of high-level radioactive waste, waste which must be isolated from the biosphere for tens of thousands of years. This chapter reviews the background of that national effort and includes some discussion of international work in order to provide a more complete framework for the problem of waste disposal. Other chapters provide the regional geologic setting, the geology of the Yucca Mountain site, the tectonics, and climate (past, present, and future). These last two chapters are integral to prediction of long-term waste isolation

Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction

Energy Technology Data Exchange (ETDEWEB)

R.A. Levich; J.S. Stuckless

2006-09-25

Yucca Mountain in Nevada represents the proposed solution to what has been a lengthy national effort to dispose of high-level radioactive waste, waste which must be isolated from the biosphere for tens of thousands of years. This chapter reviews the background of that national effort and includes some discussion of international work in order to provide a more complete framework for the problem of waste disposal. Other chapters provide the regional geologic setting, the geology of the Yucca Mountain site, the tectonics, and climate (past, present, and future). These last two chapters are integral to prediction of long-term waste isolation.

Destination: Geology?

Science.gov (United States)

Price, Louise

2016-04-01

"While we teach, we learn" (Roman philosopher Seneca) One of the most beneficial ways to remember a theory or concept is to explain it to someone else. The offer of fieldwork and visits to exciting destinations is arguably the easiest way to spark a students' interest in any subject. Geology at A-Level (age 16-18) in the United Kingdom incorporates significant elements of field studies into the curriculum with many students choosing the subject on this basis and it being a key factor in consolidating student knowledge and understanding. Geology maintains a healthy annual enrollment with interest in the subject increasing in recent years. However, it is important for educators not to loose sight of the importance of recruitment and retention of students. Recent flexibility in the subject content of the UK curriculum in secondary schools has provided an opportunity to teach the basic principles of the subject to our younger students and fieldwork provides a valuable opportunity to engage with these students in the promotion of the subject. Promotion of the subject is typically devolved to senior students at Hessle High School and Sixth Form College, drawing on their personal experiences to engage younger students. Prospective students are excited to learn from a guest speaker, so why not use our most senior students to engage and promote the subject rather than their normal subject teacher? A-Level geology students embarking on fieldwork abroad, understand their additional responsibility to promote the subject and share their understanding of the field visit. They will typically produce a series of lessons and activities for younger students using their newly acquired knowledge. Senior students also present to whole year groups in seminars, sharing knowledge of the location's geology and raising awareness of the exciting destinations offered by geology. Geology fieldwork is always planned, organised and led by the member of staff to keep costs low, with recent visits

HIGH TEMPERATURE, HIGH POWER HETEROGENEOUS NUCLEAR REACTOR

Science.gov (United States)

Hammond, R.P.; Wykoff, W.R.; Busey, H.M.

1960-06-14

A heterogeneous nuclear reactor is designed comprising a stationary housing and a rotatable annular core being supported for rotation about a vertical axis in the housing, the core containing a plurality of radial fuel- element supporting channels, the cylindrical empty space along the axis of the core providing a central plenum for the disposal of spent fuel elements, the core cross section outer periphery being vertically gradated in radius one end from the other to provide a coolant duct between the core and the housing, and means for inserting fresh fuel elements in the supporting channels under pressure and while the reactor is in operation.

Preliminary analysis on the disposal of high-level radioactive wastes in geological formations of Sao Paulo state, Brazil

International Nuclear Information System (INIS)

Mattos, Luis Antonio Terribile de

1981-01-01

Several studies show that deep geological formations are the most promising solution - technical and economical - for the safe disposal of the high-level radioactive wastes produced by the nuclear industry. In order to obtain the necessary information to assess on the use of geological sites in Brazil - for the disposal of high-level radioactive waste generated by the brazilian nuclear industry - a careful survey on the basalt and granite rocks of Sao Paulo State was made. The data obtained were evaluated according to guidelines established by the International Atomic Energy Agency. The favourable and unfavourable characteristics of the basalts, granites and their respective occurrence areas in the Sao Paulo state territory - as potential waste disposal sites - were analysed. This preliminary and regional characterization is not a conclusive study whether these two rocks types are definitively the most suitable geological formations for use as nuclear waste repository or not. It is the subsidy for a more detailed analysis. Other factors such as social, political and economical aspects, ecological effects, engineering geology, heat generation rate of the waste, type of radiation emitted and corrosive nature of the waste must also be taken into account. (author)

A note on variational multiscale methods for high-contrast heterogeneous porous media flows with rough source terms

KAUST Repository

Calo, Victor M.

2011-09-01

In this short note, we discuss variational multiscale methods for solving porous media flows in high-contrast heterogeneous media with rough source terms. Our objective is to separate, as much as possible, subgrid effects induced by the media properties from those due to heterogeneous source terms. For this reason, enriched coarse spaces designed for high-contrast multiscale problems are used to represent the effects of heterogeneities of the media. Furthermore, rough source terms are captured via auxiliary correction equations that appear in the formulation of variational multiscale methods [23]. These auxiliary equations are localized and one can use additive or multiplicative constructions for the subgrid corrections as discussed in the current paper. Our preliminary numerical results show that one can capture the effects due to both spatial heterogeneities in the coefficients (such as permeability field) and source terms (e.g., due to singular well terms) in one iteration. We test the cases for both smooth source terms and rough source terms and show that with the multiplicative correction, the numerical approximations are more accurate compared to the additive correction. © 2010 Elsevier Ltd.

Viewpoint of defining the groundwater chemistry for the performance assessment on geological disposal of high level radioactive waste

International Nuclear Information System (INIS)

Sasamoto, Hiroshi; Yui, Mikazu

2000-01-01

This report presents the viewpoint of defining the groundwater chemistry for performance assessment of the second progress report for research and development on geological disposal. Based on the results of statistical analysis (binary scatter plots) of the measured data in addition to the consideration of the first progress report, we defined the five hypothetically modeled groundwaters considering the general geological conditions and importance for performance assessment. In order to evaluate the priority of groundwater chemistries, we have analyzed the above five hypothetical groundwaters by considering the results of multivariate statistical analyses, data reliability, evidence for geochemical controls on groundwater chemistry and exclusion criteria for potential repository sites in Japan. As a result, the fresh reducing high pH (FRHP) type groundwater has been selected for the Reference Case analysis, and the saline reducing high pH (SRHP) type groundwater has been selected for the Alternative Geological Environmental Case analysis, respectively. (author)

Conceptual design of the Virtual Engineering System for High Level Radioactive Waste Geological Disposal

International Nuclear Information System (INIS)

1999-06-01

The Virtual Engineering System for the High Level Radioactive Waste Geological Disposal (hereafter the VE) adopts such computer science technologies as advanced numerical simulation technology with special emphasis upon computer graphics, massive parallel computing, high speed networking, knowledge engineering, database technology to virtually construct the natural and the part of social environment of disposal site in syberspace to realize the disposal OS as its final target. The principle of tile VE is to provide for a firm business standpoint after The 2000 Report by JNC and supply decision support system which promotes various evaluations needed to be done from the year of 2000 to the licensing application for disposal to the government. The VE conceptual design was performed in the year of 1998. The functions of the VE are derived from the analysis of work scope of implementing organization in each step of geological waste disposal: the VE functions need the safety performance assessment, individual process analysis, facility designing, cost evaluation, site surveillance, research and development, public acceptance. Then the above functions are materialized by integrating such individual system as geology database, groundwater database, safety performance assessment system, coupled phenomena analysis system, decision support system, cost evaluation system, and public acceptance system. The integration method of the systems was studied. The concept of the integration of simulators has also been studied from the view point of CAPASA program. Parallel computing, networking, and computer graphic for high speed massive scientific calculation were studied in detail as the element technology to achieve the VE. Based on studies stated above, the concept of the waste disposal project and subjects that arise from 1999 to licensing application are decided. (author)

Micrometer-scale magnetic imaging of geological samples using a quantum diamond microscope

Science.gov (United States)

Glenn, D. R.; Fu, R. R.; Kehayias, P.; Le Sage, D.; Lima, E. A.; Weiss, B. P.; Walsworth, R. L.

2017-08-01

Remanent magnetization in geological samples may record the past intensity and direction of planetary magnetic fields. Traditionally, this magnetization is analyzed through measurements of the net magnetic moment of bulk millimeter to centimeter sized samples. However, geological samples are often mineralogically and texturally heterogeneous at submillimeter scales, with only a fraction of the ferromagnetic grains carrying the remanent magnetization of interest. Therefore, characterizing this magnetization in such cases requires a technique capable of imaging magnetic fields at fine spatial scales and with high sensitivity. To address this challenge, we developed a new instrument, based on nitrogen-vacancy centers in diamond, which enables direct imaging of magnetic fields due to both remanent and induced magnetization, as well as optical imaging, of room-temperature geological samples with spatial resolution approaching the optical diffraction limit. We describe the operating principles of this device, which we call the quantum diamond microscope (QDM), and report its optimized image-area-normalized magnetic field sensitivity (20 µTṡµm/Hz1/2), spatial resolution (5 µm), and field of view (4 mm), as well as trade-offs between these parameters. We also perform an absolute magnetic field calibration for the device in different modes of operation, including three-axis (vector) and single-axis (projective) magnetic field imaging. Finally, we use the QDM to obtain magnetic images of several terrestrial and meteoritic rock samples, demonstrating its ability to resolve spatially distinct populations of ferromagnetic carriers.

Geological disposal: security and R and D. Security of 'second draft for R and D of geological disposal'

International Nuclear Information System (INIS)

Shiotsuki, Masao; Miyahara, Kaname

2003-01-01

The second draft for R and D of geological disposal (second draft) was arranged in 1999. The idea of security of geological disposal in the second draft is explained. The evaluation results of the uncertainty analysis and an example of evaluation of the effect of separation nuclear transmutation on the geological disposal are shown. The construction of strong engineered barrier is a basic idea of geological disposal system. Three processes such as isolation, engineering countermeasures and safety evaluation are carried out for the security of geological disposal. The security of geological environment for a long time of 12 sites in Japan was studied by data. Provability of production and enforcement of engineered barrier were confirmed by trial of over pack, tests and the present and future technologies developed. By using the conditions of reference case in the second draft, the evaluation results of dose effects in the two cases: 1) 90 to 99% Cs and Sr removed from HLW (High Level radioactive Waste) and 2) high stripping ratio of actinium series are explained. (S.Y.)

Mathematical modelling of heat production in deep geological repository of high-level nuclear waste

International Nuclear Information System (INIS)

Kovanda, O.

2017-01-01

Waste produced by nuclear industry requires special handling. Currently, there is a research taking place, focused at possibilities of nuclear waste storage in deep geological repositories, hosted in stable geological environment. The high-level nuclear waste produces significant amount of heat for a long time, which can affect either environment outside of or within the repository in a negative way. Therefore to reduce risks, it is desirable to know the principles of such heat production, which can be achieved using mathematical modeling. This thesis comes up with a general model of heat production-time dependency, dependable on initial composition of the waste. To be able to model real situations, output of this thesis needs to be utilized in an IT solution. (authors)

Quantifying geological processes on Mars - Results of the high resolution stereo camera (HRSC) on Mars express

NARCIS (Netherlands)

Jaumann, R.; Tirsch, D.; Hauber, E.; Ansan, V.; Di Achille, G.; Erkeling, G.; Fueten, F.; Head, J.; Kleinhans, M. G.; Mangold, N.; Michael, G. G.; Neukum, G.; Pacifici, A.; Platz, T.; Pondrelli, M.; Raack, J.; Reiss, D.; Williams, D. A.; Adeli, S.; Baratoux, D.; De Villiers, G.; Foing, B.; Gupta, S.; Gwinner, K.; Hiesinger, H.; Hoffmann, H.; Deit, L. Le; Marinangeli, L.; Matz, K. D.; Mertens, V.; Muller, J. P.; Pasckert, J. H.; Roatsch, T.; Rossi, A. P.; Scholten, F.; Sowe, M.; Voigt, J.; Warner, N.

2015-01-01

Abstract This review summarizes the use of High Resolution Stereo Camera (HRSC) data as an instrumental tool and its application in the analysis of geological processes and landforms on Mars during the last 10 years of operation. High-resolution digital elevations models on a local to regional scale

Bird diversity and environmental heterogeneity in North America: A test of the area-heterogeneity trade-off

Science.gov (United States)

Rachel Chocron; Curtis H. Flather; Ronen Kadmon

2015-01-01

Aim: Deterministic niche theory predicts that increasing environmental heterogeneity increases species richness. In contrast, a recent stochastic model suggests that heterogeneity has a unimodal effect on species richness since high levels of heterogeneity reduce the effective area available per species, thereby increasing the likelihood of stochastic...

High Intra- and Inter-Tumoral Heterogeneity of RAS Mutations in Colorectal Cancer

Directory of Open Access Journals (Sweden)

Marion Jeantet

2016-12-01

Full Text Available Approximately 30% of patients with wild type RAS metastatic colorectal cancer are non-responders to anti-epidermal growth factor receptor monoclonal antibodies (anti-EGFR mAbs, possibly due to undetected tumoral subclones harboring RAS mutations. The aim of this study was to analyze the distribution of RAS mutations in different areas of the primary tumor, metastatic lymph nodes and distant metastasis. A retrospective cohort of 18 patients with a colorectal cancer (CRC was included in the study. Multiregion analysis was performed in 60 spatially separated tumor areas according to the pathological tumor node metastasis (pTNM staging and KRAS, NRAS and BRAF mutations were tested using pyrosequencing. In primary tumors, intra-tumoral heterogeneity for RAS mutation was found in 33% of cases. Inter-tumoral heterogeneity for RAS mutation between primary tumors and metastatic lymph nodes or distant metastasis was found in 36% of cases. Moreover, 28% of tumors had multiple RAS mutated subclones in the same tumor. A high proportion of CRCs presented intra- and/or inter-tumoral heterogeneity, which has relevant clinical implications for anti-EGFR mAbs prescription. These results suggest the need for multiple RAS testing in different parts of the same tumor and/or more sensitive techniques.

Geology of the Yucca Mountain Region, Chapter in Stuckless, J.S., ED., Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste

International Nuclear Information System (INIS)

J.S. Stuckless; D. O'Leary

2006-01-01

Yucca Mountain has been proposed as the site for the Nation's first geologic repository for high-level radioactive waste. This chapter provides the geologic framework for the Yucca Mountain region. The regional geologic units range in age from late Precambrian through Holocene, and these are described briefly. Yucca Mountain is composed dominantly of pyroclastic units that range in age from 11.4 to 15.2 Ma. The proposed repository would be constructed within the Topopah Spring Tuff, which is the lower of two major zoned and welded ash-flow tuffs within the Paintbrush Group. The two welded tuffs are separated by the partly to nonwelded Pah Canyon Tuff and Yucca Mountain Tuff, which together figure prominently in the hydrology of the unsaturated zone. The Quaternary deposits are primarily alluvial sediments with minor basaltic cinder cones and flows. Both have been studied extensively because of their importance in predicting the long-term performance of the proposed repository. Basaltic volcanism began about 10 Ma and continued as recently as about 80 ka with the eruption of cones and flows at Lathrop Wells, approximately 10 km south-southwest of Yucca Mountain. Geologic structure in the Yucca Mountain region is complex. During the latest Paleozoic and Mesozoic, strong compressional forces caused tight folding and thrust faulting. The present regional setting is one of extension, and normal faulting has been active from the Miocene through to the present. There are three major local tectonic domains: (1) Basin and Range, (2) Walker Lane, and (3) Inyo-Mono. Each domain has an effect on the stability of Yucca Mountain

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

Science.gov (United States)

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. Copyright © 2015 Elsevier B.V. All rights reserved.

Structural Optimization of a High-Speed Press Considering Multi-Source Uncertainties Based on a New Heterogeneous TOPSIS

Directory of Open Access Journals (Sweden)

Jin Cheng

2018-01-01

Full Text Available In order to achieve high punching precision, good operational reliability and low manufacturing cost, the structural optimization of a high-speed press in the presence of a set of available alternatives comprises a heterogeneous multiple-attribute decision-making (HMADM problem involving deviation, fixation, cost and benefit attributes that can be described in various mathematical forms due to the existence of multi-source uncertainties. Such a HMADM problem cannot be easily resolved by existing methods. To overcome this difficulty, a new heterogeneous technique for order preference by similarity to an ideal solution (HTOPSIS is proposed. A new approach to normalization of heterogeneous attributes is proposed by integrating the possibility degree method, relative preference relation and the attribute transformation technique. Expressions for determining positive and negative ideal solutions corresponding to heterogeneous attributes are also developed. Finally, alternative structural configurations are ranked according to their relative closeness coefficients, and the optimal structural configuration can be determined. The validity and effectiveness of the proposed HTOPSIS are demonstrated by a numerical example. The proposed HTOPSIS can also be applied to structural optimization of other complex equipment, because there is no prerequisite of independency among various attributes for its application.

China's deep geological disposal program for high level radioactive waste, background and status 1998

International Nuclear Information System (INIS)

Ju Wang; Xu Guoqing; Guo Yonghai

2001-01-01

This paper presents the background and progress made in the study of China's high level radioactive waste, including site screening, site evaluation, the study on radionuclide migration, bentonite, natural analogue studies, and performance assessment, etc. The study on Beishan area, the potential area for China's geological repository, is also presented in this paper. (author)

Environmental remediation of high-level nuclear waste in geological repository. Modified computer code creates ultimate benchmark in natural systems

International Nuclear Information System (INIS)

Peter, Geoffrey J.

2011-01-01

Isolation of high-level nuclear waste in permanent geological repositories has been a major concern for over 30 years due to the migration of dissolved radio nuclides reaching the water table (10,000-year compliance period) as water moves through the repository and the surrounding area. Repositories based on mathematical models allow for long-term geological phenomena and involve many approximations; however, experimental verification of long-term processes is impossible. Countries must determine if geological disposal is adequate for permanent storage. Many countries have extensively studied different aspects of safely confining the highly radioactive waste in an underground repository based on the unique geological composition at their selected repository location. This paper discusses two computer codes developed by various countries to study the coupled thermal, mechanical, and chemical process in these environments, and the migration of radionuclide. Further, this paper presents the results of a case study of the Magma-hydrothermal (MH) computer code, modified by the author, applied to nuclear waste repository analysis. The MH code verified by simulating natural systems thus, creating the ultimate benchmark. This approach based on processes similar to those expected near waste repositories currently occurring in natural systems. (author)

High-Dimensional Adaptive Particle Swarm Optimization on Heterogeneous Systems

International Nuclear Information System (INIS)

Wachowiak, M P; Sarlo, B B; Foster, A E Lambe

2014-01-01

Much work has recently been reported in parallel GPU-based particle swarm optimization (PSO). Motivated by the encouraging results of these investigations, while also recognizing the limitations of GPU-based methods for big problems using a large amount of data, this paper explores the efficacy of employing other types of parallel hardware for PSO. Most commodity systems feature a variety of architectures whose high-performance capabilities can be exploited. In this paper, high-dimensional problems and those that employ a large amount of external data are explored within the context of heterogeneous systems. Large problems are decomposed into constituent components, and analyses are undertaken of which components would benefit from multi-core or GPU parallelism. The current study therefore provides another demonstration that ''supercomputing on a budget'' is possible when subtasks of large problems are run on hardware most suited to these tasks. Experimental results show that large speedups can be achieved on high dimensional, data-intensive problems. Cost functions must first be analysed for parallelization opportunities, and assigned hardware based on the particular task

Conceptual design of the virtual engineering system for high level radioactive waste geological disposal

International Nuclear Information System (INIS)

2000-02-01

The role of Virtual Engineering System for High Level Radioactive Waste Geological Disposal (hereafter the VES) is to accumulate and unify the results of research and development which JNC had been carried out for the completion of the second progress report on a computer system. The purpose and functions of VES with considering the long-term plan for geological disposal in Japan was studied. The analysis between geological environment assessment, safety performance assessment, and engineering technology had not been integrated mutually in the conventional study. The iterative analysis performed by VES makes it possible to analyze natural barrier and engineering barrier more quantitatively for obtaining safety margin and rationalization of the design of a waste repository. We have examined the system functions to achieve the above purpose of VES. Next, conceptual design for codes, databases, and utilities that consist of VES were performed by examining their purpose and functions. The conceptual design of geological environment assessment system, safety performance assessment system, waste repository element database, economical assessment system, investigation support system, quality assurance system, and visualization system are preformed. The whole system configuration, examination of suitable configuration of hardware and software, examination of system implementation, the confirmation of parallel calculation technology, the conceptual design of platform, the development of demonstration program of platform are performed. Based upon studies stated above, the VES development plan including prototype development during the period of selection of the site candidate was studied. The concept of VES was build based on the examination stated above. (author)

Geologic Framework Model (GFM2000)

International Nuclear Information System (INIS)

T. Vogt

2004-01-01

The purpose of this report is to document the geologic framework model, version GFM2000 with regard to input data, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, and the differences between GFM2000 and previous versions. The version number of this model reflects the year during which the model was constructed. This model supersedes the previous model version, documented in Geologic Framework Model (GFM 3.1) (CRWMS M and O 2000 [DIRS 138860]). The geologic framework model represents a three-dimensional interpretation of the geology surrounding the location of the monitored geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain. The geologic framework model encompasses and is limited to an area of 65 square miles (168 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the geologic framework model (shown in Figure 1-1) were chosen to encompass the exploratory boreholes and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The upper surface of the model is made up of the surface topography and the depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The geologic framework model was constructed from geologic map and borehole data. Additional information from measured stratigraphic sections, gravity profiles, and seismic profiles was also considered. The intended use of the geologic framework model is to provide a geologic framework over the area of interest consistent with the level of detailed needed for hydrologic flow and radionuclide transport modeling through the UZ and for repository design. The model is limited by the availability of data and relative amount of geologic complexity found in an area. The geologic framework model is inherently limited by scale and content. The grid spacing used in

Geologic Framework Model (GFM2000)

Energy Technology Data Exchange (ETDEWEB)

T. Vogt

2004-08-26

The purpose of this report is to document the geologic framework model, version GFM2000 with regard to input data, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, and the differences between GFM2000 and previous versions. The version number of this model reflects the year during which the model was constructed. This model supersedes the previous model version, documented in Geologic Framework Model (GFM 3.1) (CRWMS M&O 2000 [DIRS 138860]). The geologic framework model represents a three-dimensional interpretation of the geology surrounding the location of the monitored geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain. The geologic framework model encompasses and is limited to an area of 65 square miles (168 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the geologic framework model (shown in Figure 1-1) were chosen to encompass the exploratory boreholes and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The upper surface of the model is made up of the surface topography and the depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The geologic framework model was constructed from geologic map and borehole data. Additional information from measured stratigraphic sections, gravity profiles, and seismic profiles was also considered. The intended use of the geologic framework model is to provide a geologic framework over the area of interest consistent with the level of detailed needed for hydrologic flow and radionuclide transport modeling through the UZ and for repository design. The model is limited by the availability of data and relative amount of geologic complexity found in an area. The geologic framework model is inherently limited by scale and content. The grid spacing used in the

How to Shape a Successful Repository Program: Staged Development of Geologic Repositories for High-Level Waste

International Nuclear Information System (INIS)

Isaacs, T.

2004-01-01

Programs to manage and ultimately dispose of high-level radioactive wastes are unique from scientific and technological as well as socio-political aspects. From a scientific and technological perspective, high-level radioactive wastes remain potentially hazardous for geological time periods--many millennia--and scientific and technological programs must be put in place that result in a system that provides high confidence that the wastes will be isolated from the accessible environment for these many thousands of years. Of course, ''proof'' in the classical sense is not possible at the outset, since the performance of the system can only be known with assurance, if ever, after the waste has been emplaced for those geological time periods. Adding to this challenge, many uncertainties exist in both the natural and engineered systems that are intended to isolate the wastes, and some of the uncertainties will remain regardless of the time and expense in attempting to characterize the system and assess its performance

How to Shape a Successful Repository Program: Staged Development of Geologic Repositories for High-Level Waste

Energy Technology Data Exchange (ETDEWEB)

Isaacs, T.

2004-10-03

Programs to manage and ultimately dispose of high-level radioactive wastes are unique from scientific and technological as well as socio-political aspects. From a scientific and technological perspective, high-level radioactive wastes remain potentially hazardous for geological time periods--many millennia--and scientific and technological programs must be put in place that result in a system that provides high confidence that the wastes will be isolated from the accessible environment for these many thousands of years. Of course, ''proof'' in the classical sense is not possible at the outset, since the performance of the system can only be known with assurance, if ever, after the waste has been emplaced for those geological time periods. Adding to this challenge, many uncertainties exist in both the natural and engineered systems that are intended to isolate the wastes, and some of the uncertainties will remain regardless of the time and expense in attempting to characterize the system and assess its performance.

Using environmental heterogeneity to plan for sea-level rise.

Science.gov (United States)

Hunter, Elizabeth A; Nibbelink, Nathan P

2017-12-01

Environmental heterogeneity is increasingly being used to select conservation areas that will provide for future biodiversity under a variety of climate scenarios. This approach, termed conserving nature's stage (CNS), assumes environmental features respond to climate change more slowly than biological communities, but will CNS be effective if the stage were to change as rapidly as the climate? We tested the effectiveness of using CNS to select sites in salt marshes for conservation in coastal Georgia (U.S.A.), where environmental features will change rapidly as sea level rises. We calculated species diversity based on distributions of 7 bird species with a variety of niches in Georgia salt marshes. Environmental heterogeneity was assessed across six landscape gradients (e.g., elevation, salinity, and patch area). We used 2 approaches to select sites with high environmental heterogeneity: site complementarity (environmental diversity [ED]) and local environmental heterogeneity (environmental richness [ER]). Sites selected based on ER predicted present-day species diversity better than randomly selected sites (up to an 8.1% improvement), were resilient to areal loss from SLR (1.0% average areal loss by 2050 compared with 0.9% loss of randomly selected sites), and provided habitat to a threatened species (0.63 average occupancy compared with 0.6 average occupancy of randomly selected sites). Sites selected based on ED predicted species diversity no better or worse than random and were not resilient to SLR (2.9% average areal loss by 2050). Despite the discrepancy between the 2 approaches, CNS is a viable strategy for conservation site selection in salt marshes because the ER approach was successful. It has potential for application in other coastal areas where SLR will affect environmental features, but its performance may depend on the magnitude of geological changes caused by SLR. Our results indicate that conservation planners that had heretofore excluded low

Experiments and Simulations of Fluid Flow in Heterogeneous Reservoir Models - Emphasis on Impacts from Crossbeds and Fractures

Energy Technology Data Exchange (ETDEWEB)

Boerresen, Knut Arne

1996-12-31

Hydrocarbon recovery from subsurface reservoirs has become increasingly dependent on advanced recovery techniques that require improved understanding of the physics of fluid flow within and across geological units including small-scale heterogeneities and fractures. In this thesis, impacts from heterogeneities on local fluid flow are studied experimentally by means of imaging techniques to visualize fluid flow in two dimensions during flooding of larger reservoir models. Part 1 reflects the multi-disciplinary collaboration, by briefly introducing the relevant geology, the literature on experiments on fluid flow in bedded structures, and outlining the applied numerical simulator and imaging techniques applied to visualize fluid flow. The second part contains a synopsis of displacement experiments in naturally laminated sandstones and in crossbed laboratory models, and of the impact from incipient shear fractures on oil recovery. The detailed results obtained from the experiments and simulations are described in six papers, all included. 215 refs., 108 figs., 16 tabs.

Experiments and Simulations of Fluid Flow in Heterogeneous Reservoir Models - Emphasis on Impacts from Crossbeds and Fractures

Energy Technology Data Exchange (ETDEWEB)

Boerresen, Knut Arne

1997-12-31

Hydrocarbon recovery from subsurface reservoirs has become increasingly dependent on advanced recovery techniques that require improved understanding of the physics of fluid flow within and across geological units including small-scale heterogeneities and fractures. In this thesis, impacts from heterogeneities on local fluid flow are studied experimentally by means of imaging techniques to visualize fluid flow in two dimensions during flooding of larger reservoir models. Part 1 reflects the multi-disciplinary collaboration, by briefly introducing the relevant geology, the literature on experiments on fluid flow in bedded structures, and outlining the applied numerical simulator and imaging techniques applied to visualize fluid flow. The second part contains a synopsis of displacement experiments in naturally laminated sandstones and in crossbed laboratory models, and of the impact from incipient shear fractures on oil recovery. The detailed results obtained from the experiments and simulations are described in six papers, all included. 215 refs., 108 figs., 16 tabs.

Onshore/ Offshore Geologic Assessment for Carbon Storage in the Southeastern United States

Science.gov (United States)

Knapp, C. C.; Knapp, J. H.; Brantley, D.; Lakshmi, V.; Almutairi, K.; Almayahi, D.; Akintunde, O. M.; Ollmann, J.

2017-12-01

Eighty percent of the world's energy relies on fossil fuels and under increasingly stricter national and international regulations on greenhouse gas emissions storage of CO2 in geologic repositories seems to be not only a feasible, but also and vital solution for near/ mid-term reduction of carbon emissions. We have evaluated the feasibility of CO2 storage in saline formations of the Eastern North American Margin (ENAM) including (1) the Jurassic/Triassic (J/TR) sandstones of the buried South Georgia Rift (SGR) basin, and (2) the Mesozoic and Cenozoic geologic formations along the Mid- and South Atlantic seaboard. These analyses have included integration of subsurface geophysical data (2- and 3-D seismic surveys) with core samples, well logs as well as uses of geological databases and geospatial analysis leading to CO2 injection simulation models. ENAM is a complex and regionally extensive mature Mesozoic passive margin rift system encompassing: (1) a large volume and regional extent of related magmatism known as the Central Atlantic Magmatic Province (CAMP), (2) a complete stratigraphic column that records the post-rift evolution in several basins, (3) preserved lithospheric-scale pre-rift structures including Paleozoic sutures, and (4) a wide range of geological, geochemical, and geophysical studies both onshore and offshore. While the target reservoirs onshore show heterogeneity and a highly complex geologic evolution they also show promising conditions for significant safe CO2 storage away from the underground acquifers. Our offshore study (the Southeast Offshore Storage Resource Assessment - SOSRA) is focused on the outer continental shelf from North Carolina to the southern tip of Florida. Three old exploration wells are available to provide additional constraints on the seismic reflection profiles. Two of these wells (TRANSCO 1005-1 and COST GE-1) penetrate the pre-rift Paleozoic sedimentary formations while the EXXON 564-1 well penetrates the post

Spatial heterogeneity as a genetic mixing mechanism in highly philopatric colonial seabirds.

Science.gov (United States)

Cristofari, Robin; Trucchi, Emiliano; Whittington, Jason D; Vigetta, Stéphanie; Gachot-Neveu, Hélène; Stenseth, Nils Christian; Le Maho, Yvon; Le Bohec, Céline

2015-01-01

How genetic diversity is maintained in philopatric colonial systems remains unclear, and understanding the dynamic balance of philopatry and dispersal at all spatial scales is essential to the study of the evolution of coloniality. In the King penguin, Aptenodytes patagonicus, return rates of post-fledging chicks to their natal sub-colony are remarkably high. Empirical studies have shown that adults return year after year to their previous breeding territories within a radius of a few meters. Yet, little reliable data are available on intra- and inter-colonial dispersal in this species. Here, we present the first fine-scale study of the genetic structure in a king penguin colony in the Crozet Archipelago. Samples were collected from individual chicks and analysed at 8 microsatellite loci. Precise geolocation data of hatching sites and selective pressures associated with habitat features were recorded for all sampling locations. We found that despite strong natal and breeding site fidelity, king penguins retain a high degree of panmixia and genetic diversity. Yet, genetic structure appears markedly heterogeneous across the colony, with higher-than-expected inbreeding levels, and local inbreeding and relatedness hotspots that overlap predicted higher-quality nesting locations. This points towards heterogeneous population structure at the sub-colony level, in which fine-scale environmental features drive local philopatric behaviour, while lower-quality patches may act as genetic mixing mechanisms at the colony level. These findings show how a lack of global genetic structuring can emerge from small-scale heterogeneity in ecological parameters, as opposed to the classical model of homogeneous dispersal. Our results also emphasize the importance of sampling design for estimation of population parameters in colonial seabirds, as at high spatial resolution, basic genetic features are shown to be location-dependent. Finally, this study stresses the importance of

Spatial heterogeneity as a genetic mixing mechanism in highly philopatric colonial seabirds.

Directory of Open Access Journals (Sweden)

Robin Cristofari

Full Text Available How genetic diversity is maintained in philopatric colonial systems remains unclear, and understanding the dynamic balance of philopatry and dispersal at all spatial scales is essential to the study of the evolution of coloniality. In the King penguin, Aptenodytes patagonicus, return rates of post-fledging chicks to their natal sub-colony are remarkably high. Empirical studies have shown that adults return year after year to their previous breeding territories within a radius of a few meters. Yet, little reliable data are available on intra- and inter-colonial dispersal in this species. Here, we present the first fine-scale study of the genetic structure in a king penguin colony in the Crozet Archipelago. Samples were collected from individual chicks and analysed at 8 microsatellite loci. Precise geolocation data of hatching sites and selective pressures associated with habitat features were recorded for all sampling locations. We found that despite strong natal and breeding site fidelity, king penguins retain a high degree of panmixia and genetic diversity. Yet, genetic structure appears markedly heterogeneous across the colony, with higher-than-expected inbreeding levels, and local inbreeding and relatedness hotspots that overlap predicted higher-quality nesting locations. This points towards heterogeneous population structure at the sub-colony level, in which fine-scale environmental features drive local philopatric behaviour, while lower-quality patches may act as genetic mixing mechanisms at the colony level. These findings show how a lack of global genetic structuring can emerge from small-scale heterogeneity in ecological parameters, as opposed to the classical model of homogeneous dispersal. Our results also emphasize the importance of sampling design for estimation of population parameters in colonial seabirds, as at high spatial resolution, basic genetic features are shown to be location-dependent. Finally, this study stresses the

Digitizing rocks: Standardizing the process of geologic description with workstations

International Nuclear Information System (INIS)

Saunders, M.R.; Shields, J.A.; Taylor, M.R.

1995-01-01

In the drive to squeeze the most value from every dollar spent on exploration and development, increasing use is being made of stored data through methods that rely on the completeness and accuracy of the database for their usefulness. Although many types of engineering data are available to the process, geologic data, especially those collected at a sufficiently detailed level to show reservoir heterogeneity, are often unavailable to later workers in any useful form. Traditionally, most wellsite geologic data are recorded on worksheets or notebooks, from which summary data are often transferred to computers. The only changes in recent years have been related to the process by which computer-drafted lithology logs have superseded hand-drawn logs; in some exceptions, some of the plotting data may be held in a simple database. These descriptions and analyses, gathered at considerable cost and capable of showing significant petrological detail, are not available to the whole field-development process. The authors set out to tackle these problems of limited usefulness and development a system that would deliver quality geologic data deep into the field of play in a form that was easy to select and integrated with existing models

Laser-Induced Fluorescence Detection in High-Throughput Screening of Heterogeneous Catalysts and Single Cells Analysis

Energy Technology Data Exchange (ETDEWEB)

Su, Hui [Iowa State Univ., Ames, IA (United States)

2001-01-01

Laser-induced fluorescence detection is one of the most sensitive detection techniques and it has found enormous applications in various areas. The purpose of this research was to develop detection approaches based on laser-induced fluorescence detection in two different areas, heterogeneous catalysts screening and single cell study. First, the author introduced laser-induced imaging (LIFI) as a high-throughput screening technique for heterogeneous catalysts to explore the use of this high-throughput screening technique in discovery and study of various heterogeneous catalyst systems. This scheme is based on the fact that the creation or the destruction of chemical bonds alters the fluorescence properties of suitably designed molecules. By irradiating the region immediately above the catalytic surface with a laser, the fluorescence intensity of a selected product or reactant can be imaged by a charge-coupled device (CCD) camera to follow the catalytic activity as a function of time and space. By screening the catalytic activity of vanadium pentoxide catalysts in oxidation of naphthalene, they demonstrated LIFI has good detection performance and the spatial and temporal resolution needed for high-throughput screening of heterogeneous catalysts. The sample packing density can reach up to 250 x 250 subunits/cm² for 40-μm wells. This experimental set-up also can screen solid catalysts via near infrared thermography detection. In the second part of this dissertation, the author used laser-induced native fluorescence coupled with capillary electrophoresis (LINF-CE) and microscope imaging to study the single cell degranulation. On the basis of good temporal correlation with events observed through an optical microscope, they have identified individual peaks in the fluorescence electropherograms as serotonin released from the granular core on contact with the surrounding fluid.

Stability of faults with heterogeneous friction properties and effective normal stress

Science.gov (United States)

Luo, Yingdi; Ampuero, Jean-Paul

2018-05-01

Abundant geological, seismological and experimental evidence of the heterogeneous structure of natural faults motivates the theoretical and computational study of the mechanical behavior of heterogeneous frictional fault interfaces. Fault zones are composed of a mixture of materials with contrasting strength, which may affect the spatial variability of seismic coupling, the location of high-frequency radiation and the diversity of slip behavior observed in natural faults. To develop a quantitative understanding of the effect of strength heterogeneity on the mechanical behavior of faults, here we investigate a fault model with spatially variable frictional properties and pore pressure. Conceptually, this model may correspond to two rough surfaces in contact along discrete asperities, the space in between being filled by compressed gouge. The asperities have different permeability than the gouge matrix and may be hydraulically sealed, resulting in different pore pressure. We consider faults governed by rate-and-state friction, with mixtures of velocity-weakening and velocity-strengthening materials and contrasts of effective normal stress. We systematically study the diversity of slip behaviors generated by this model through multi-cycle simulations and linear stability analysis. The fault can be either stable without spontaneous slip transients, or unstable with spontaneous rupture. When the fault is unstable, slip can rupture either part or the entire fault. In some cases the fault alternates between these behaviors throughout multiple cycles. We determine how the fault behavior is controlled by the proportion of velocity-weakening and velocity-strengthening materials, their relative strength and other frictional properties. We also develop, through heuristic approximations, closed-form equations to predict the stability of slip on heterogeneous faults. Our study shows that a fault model with heterogeneous materials and pore pressure contrasts is a viable framework

in Heterogeneous Media

Directory of Open Access Journals (Sweden)

Saeed Balouchi

2013-01-01

Full Text Available Fractured reservoirs contain about 85 and 90 percent of oil and gas resources respectively in Iran. A comprehensive study and investigation of fractures as the main factor affecting fluid flow or perhaps barrier seems necessary for reservoir development studies. High degrees of heterogeneity and sparseness of data have incapacitated conventional deterministic methods in fracture network modeling. Recently, simulated annealing (SA has been applied to generate stochastic realizations of spatially correlated fracture networks by assuming that the elastic energy of fractures follows Boltzmann distribution. Although SA honors local variability, the objective function of geometrical fracture modeling is defined for homogeneous conditions. In this study, after the introduction of SA and the derivation of the energy function, a novel technique is presented to adjust the model with highly heterogeneous data for a fractured field from the southwest of Iran. To this end, the regular object-based model is combined with a grid-based technique to cover the heterogeneity of reservoir properties. The original SA algorithm is also modified by being constrained in different directions and weighting the energy function to make it appropriate for heterogeneous conditions. The simulation results of the presented approach are in good agreement with the observed field data.

Geology of the Yucca Mountain Region, Chapter in Stuckless, J.S., ED., Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste

Energy Technology Data Exchange (ETDEWEB)

J.S. Stuckless; D. O' Leary

2006-09-25

Yucca Mountain has been proposed as the site for the Nation's first geologic repository for high-level radioactive waste. This chapter provides the geologic framework for the Yucca Mountain region. The regional geologic units range in age from late Precambrian through Holocene, and these are described briefly. Yucca Mountain is composed dominantly of pyroclastic units that range in age from 11.4 to 15.2 Ma. The proposed repository would be constructed within the Topopah Spring Tuff, which is the lower of two major zoned and welded ash-flow tuffs within the Paintbrush Group. The two welded tuffs are separated by the partly to nonwelded Pah Canyon Tuff and Yucca Mountain Tuff, which together figure prominently in the hydrology of the unsaturated zone. The Quaternary deposits are primarily alluvial sediments with minor basaltic cinder cones and flows. Both have been studied extensively because of their importance in predicting the long-term performance of the proposed repository. Basaltic volcanism began about 10 Ma and continued as recently as about 80 ka with the eruption of cones and flows at Lathrop Wells, approximately 10 km south-southwest of Yucca Mountain. Geologic structure in the Yucca Mountain region is complex. During the latest Paleozoic and Mesozoic, strong compressional forces caused tight folding and thrust faulting. The present regional setting is one of extension, and normal faulting has been active from the Miocene through to the present. There are three major local tectonic domains: (1) Basin and Range, (2) Walker Lane, and (3) Inyo-Mono. Each domain has an effect on the stability of Yucca Mountain.

Heterogeneous gas core reactor

International Nuclear Information System (INIS)

Han, K.I.

1977-01-01

Preliminary investigations of a heterogeneous gas core reactor (HGCR) concept suggest that this potential power reactor offers distinct advantages over other existing or conceptual reactor power plants. One of the most favorable features of the HGCR is the flexibility of the power producing system which allows it to be efficiently designed to conform to a desired optimum condition without major conceptual changes. The arrangement of bundles of moderator/coolant channels in a fissionable gas or mixture of gases makes a truly heterogeneous nuclear reactor core. It is this full heterogeneity for a gas-fueled reactor core which accounts for the novelty of the heterogeneous gas core reactor concept and leads to noted significant advantages over previous gas core systems with respect to neutron and fuel economy, power density, and heat transfer characteristics. The purpose of this work is to provide an insight into the design, operating characteristics, and safety of a heterogeneous gas core reactor system. The studies consist mainly of neutronic, energetic and kinetic analyses of the power producing and conversion systems as a preliminary assessment of the heterogeneous gas core reactor concept and basic design. The results of the conducted research indicate a high potential for the heterogeneous gas core reactor system as an electrical power generating unit (either large or small), with an overall efficiency as high as 40 to 45%. The HGCR system is found to be stable and safe, under the conditions imposed upon the analyses conducted in this work, due to the inherent safety of ann expanding gaseous fuel and the intrinsic feedback effects of the gas and water coolant

Complex geologic characterization of the repository environment

Energy Technology Data Exchange (ETDEWEB)

Harper, T R [British Petroleum Research Center, Sunberry, England; Szymanski, J S

1982-01-01

The present basis for characterizing geological environments is identified in this paper, and the additional requirements imposed by the need to isolate high-level waste safely are discussed. Solutions to these additional requirements are proposed. The time scale of concern and the apparent complexity of the required multidisciplinary approach are identified. It is proposed that an increased use of the geologic record, together with a recognition that all geologic processes operate within an interdependent system, be a key feature in geologic characterization of deep repositories.

On Fluid and Thermal Dynamics in a Heterogeneous CO2 Plume Geothermal Reservoir

Directory of Open Access Journals (Sweden)

Tianfu Xu

2017-01-01

Full Text Available CO2 is now considered as a novel heat transmission fluid to extract geothermal energy. It can achieve both the energy exploitation and CO2 geological sequestration. The migration pathway and the process of fluid flow within the reservoirs affect significantly a CO2 plume geothermal (CPG system. In this study, we built three-dimensional wellbore-reservoir coupled models using geological and geothermal conditions of Qingshankou Formation in Songliao Basin, China. The performance of the CPG system is evaluated in terms of the temperature, CO2 plume distribution, flow rate of production fluid, heat extraction rate, and storage of CO2. For obtaining a deeper understanding of CO2-geothermal system under realistic conditions, heterogeneity of reservoir’s hydrological properties (in terms of permeability and porosity is taken into account. Due to the fortissimo mobility of CO2, as long as a highly permeable zone exists between the two wells, it is more likely to flow through the highly permeable zone to reach the production well, even though the flow path is longer. The preferential flow shortens circulation time and reduces heat-exchange area, probably leading to early thermal breakthrough, which makes the production fluid temperature decrease rapidly. The analyses of flow dynamics of CO2-water fluid and heat may be useful for future design of a CO2-based geothermal development system.

Catalysts and conditions for the highly efficient, selective and stable heterogeneous oligomerisation of ethylene

CSIR Research Space (South Africa)

Heveling, J

1998-10-11

Full Text Available The oligomerisation of ethylene into products in the C-4-C-20 range over heterogeneous nickel catalysts in a fixed-bed reactor at low temperature and high pressure (LT-HP) is reported. The catalysts were obtained by Ni (II) exchange or impregnation...

Effect of granulation of geological samples in neutron transport measurements

International Nuclear Information System (INIS)

Woznicka, Urszula; Drozdowicz, Krzysztof; Gabanska, Barbara; Krynicka, Ewa; Igielski, Andrzej

2001-01-01

The thermal neutron absorption cross section is one of the parameters describing the transport of thermal neutrons in a medium. Theoretical descriptions and experiments which determine the absorption cross section have a wide literature for homogeneous media. The situation comes true e.g. for fluids or amorphous solids. There are many other media which should be treated as heterogeneous. Among others - geological materials. The material heterogeneity for the thermal neutron transport in a considered volume is understood here as an existence of many small regions which differ significantly in their macroscopic neutron diffusion parameters (defined by the absorption and transport cross sections). The final difference, which influences the neutron transport, comes from a combination of the absolute differences between the parameters and of sizes of regions (related to the neutron mean free paths). A rock can be naturally heterogeneous in the above meaning. Besides, it can happen that a preparation of the rock sample for a neutron measurement can increase its natural heterogeneity. (For example, when the rock material is crushed and the measured sample consists of the obtained grains). The question is which granulation is allowed to treat the sample material as still homogeneous, and from which size of the rock grains we have to consider a two-component medium. It has been experimentally proved that the effective absorption of thermal neutrons in a heterogeneous two-component material can significantly differ from the absorption in a homogeneous one which consists of the same elements. The final effect is dependent on a few factors: the macroscopic absorption cross sections of the components, their total mass contributions, and the size of the grains. The ratio of the effective absorption cross section of the heterogeneous material to the cross section of the equivalent homogeneous, is a measure of the heterogeneity effect on the thermal neutron absorption

Quantifying high resolution transitional breaks in plant and mammal distributions at regional extent and their association with climate, topography and geology.

Science.gov (United States)

Di Virgilio, Giovanni; Laffan, Shawn W; Ebach, Malte C

2013-01-01

We quantify spatial turnover in communities of 1939 plant and 59 mammal species at 2.5 km resolution across a topographically heterogeneous region in south-eastern Australia to identify distributional breaks and low turnover zones where multiple species distributions overlap. Environmental turnover is measured to determine how climate, topography and geology influence biotic turnover differently across a variety of biogeographic breaks and overlaps. We identify the genera driving turnover and confirm the versatility of this approach across spatial scales and locations. Directional moving window analyses, rotated through 360°, were used to measure spatial turnover variation in different directions between gridded cells containing georeferenced plant and mammal occurrences and environmental variables. Generalised linear models were used to compare taxic turnover results with equivalent analyses for geology, regolith weathering, elevation, slope, solar radiation, annual precipitation and annual mean temperature, both uniformly across the entire study area and by stratifying it into zones of high and low turnover. Identified breaks and transitions were compared to a conservation bioregionalisation framework widely used in Australia. Detailed delineations of plant and mammal turnover zones with gradational boundaries denoted subtle variation in species assemblages. Turnover patterns often diverged from bioregion boundaries, though plant turnover adhered most closely. A prominent break zone contained either comparable or greater numbers of unique genera than adjacent overlaps, but these were concentrated in a small subsection relatively under-protected by conservation reserves. The environmental correlates of biotic turnover varied for different turnover zones in different subsections of the study area. Topography and temperature showed much stronger relationships with plant turnover in a topographically complex overlap, relative to a lowland overlap where weathering

Geology of high-level nuclear waste disposal: an introduction

International Nuclear Information System (INIS)

Roxbugh, I.S.

1987-01-01

Hazardous waste is produced by the nuclear fuel cycle from mining and milling of uranium ore, refinement and enrichment, reactor use, and during reprocessing of spent fuel. Waste can be classified according to origin, physical state, and levels of radioactivity and radiotoxicity. The method of the long-term waste disposal is based on the degree of the hazard and the length of time (1000 years to millions of years) for the waste to become safe. The International Atomic Energy Agency (IAEA) has classified radioactive waste into five categories (I-V) based on the amount of radioactivity and heat output of the waste. The text is concerned mainly with the two most hazardous categories (I and II). Disposal at various geological sites using proven mining, engineering, and deep drilling techniques has been proposed and studied. An ideal geological repository would have (1) minimum ground water movement, (2) geochemical and mineralogical properties to retard or immobilize the effects of the nuclear waste from reaching the biosphere, (3) thermochemical properties to allow for heat loading without damage, and (4) structural strength for the operational period. Types of geological environments (both undersea and on land) include evaporites, crystalline rocks, and argillaceous deposits. European and North American case histories are described, and there is a glossary and an extensive list of references in this concise review

Numerical Simulation of Hydraulic Fracturing in Low-/High-Permeability, Quasi-Brittle and Heterogeneous Rocks

Science.gov (United States)

Pakzad, R.; Wang, S. Y.; Sloan, S. W.

2018-04-01

In this study, an elastic-brittle-damage constitutive model was incorporated into the coupled fluid/solid analysis of ABAQUS to iteratively calculate the equilibrium effective stress of Biot's theory of consolidation. The Young's modulus, strength and permeability parameter of the material were randomly assigned to the representative volume elements of finite element models following the Weibull distribution function. The hydraulic conductivity of elements was associated with their hydrostatic effective stress and damage level. The steady-state permeability test results for sandstone specimens under different triaxial loading conditions were reproduced by employing the same set of material parameters in coupled transient flow/stress analyses of plane-strain models, thereby indicating the reliability of the numerical model. The influence of heterogeneity on the failure response and the absolute permeability was investigated, and the post-peak permeability was found to decrease with the heterogeneity level in the coupled analysis with transient flow. The proposed model was applied to the plane-strain simulation of the fluid pressurization of a cavity within a large-scale block under different conditions. Regardless of the heterogeneity level, the hydraulically driven fractures propagated perpendicular to the minimum principal far-field stress direction for high-permeability models under anisotropic far-field stress conditions. Scattered damage elements appeared in the models with higher degrees of heterogeneity. The partially saturated areas around propagating fractures were simulated by relating the saturation degree to the negative pore pressure in low-permeability blocks under high pressure. By replicating previously reported trends in the fracture initiation and breakdown pressure for different pressurization rates and hydraulic conductivities, the results showed that the proposed model for hydraulic fracture problems is reliable for a wide range of

Geology at Yucca Mountain

International Nuclear Information System (INIS)

Anon.

1993-01-01

Both advocates and critics disagree on the significance and interpretation of critical geological features which bear on the safety and suitability of Yucca Mountain as a site for the construction of a high-level radioactive waste repository. Critics believe that there is sufficient geological evidence to rule the site unsuitable for further investigation. Some advocates claim that there is insufficient data and that investigations are incomplete, while others claim that the site is free of major obstacles. We have expanded our efforts to include both the critical evaluations of existing geological and geochemical data and the collection of field data and samples for the purpose of preparing scientific papers for submittal to journals. Summaries of the critical reviews are presented in this paper

Office of Geologic Repositories quality assurance plan for high-level radioactive waste repositories

International Nuclear Information System (INIS)

1986-08-01

This document sets forth geologic repository program-wide quality assurance program requirements and defines management's quality assurance responsibilities for the Office of Geologic Repositories and its projects. (LM)

California Geological Survey Geologic Map Index

Data.gov (United States)

California Natural Resource Agency — All the individual maps from the Geologic Atlas of California and the Regional Geologic map series have been georeferenced for display in a GIS (and viewable online...

Geology Laxemar. Site descriptive modelling SDM-Site Laxemar

Energy Technology Data Exchange (ETDEWEB)

Wahlgren, Carl-Henric (Geological Survey of Sweden, Uppsala (Sweden)); Curtis, Philip; Hermanson, Jan; Forssberg, Ola; Oehman, Johan (Golder Associates AB (Sweden)); Fox, Aaron; La Pointe, Paul (Golder Associates Inc (United States)); Drake, Henrik (Dept. of Earth Sciences, Univ. of Goeteborg, Goeteborg (Sweden)); Triumf, Carl-Axel; Mattsson, Haakan; Thunehed, Hans (GeoVista AB, Luleaa (Sweden)); Juhlin, Christopher (Dept. of Earth Sciences, Uppsala Univ., Uppsala (Sweden))

2008-11-15

, kinematics of brittle deformation in drill cores and outcrops, as well as studies with particular focus on minor deformation zones (MDZ) in both drill cores and in the field. Complementary geochronological and other rock and fracture analytical data. High resolution airborne laser scanning (LIDAR) leading to a new digital elevation model (DEM) together with high-resolution ground magnetic and resistivity data providing the basis for further lineament interpretations. Further seismic refraction surveys and reprocessing and re-evaluation of seismic reflection data. The outputs of the deterministic modelling work are geometric models in RVS format for rock domains, deformation zones and fracture domains, including detailed property tables for rock domains and deformation zones and a description of fracture domains. The outputs of the geological DFN modelling process are recommended parameters or statistical distributions that describe fracture set orientations, sizes, volumetric intensities, spatial correlations and models, and other parameters (lithology and scaling corrections, termination matrices) that are necessary for building stochastic models. The regional scale ductile deformation zones strike NNE-SSW and NE-SW, are subvertical and are characterised by sinistral strike-slip displacements, while E-W oriented zones, though more strongly overprinted by brittle deformation, display moderate to steep dips to the south or north. The kinematics of the latter are not resolved at Laxemar, but E-W ductile shear zones in the Simpevarp subarea show complex kinematics, including both reverse and normal dip-slip as well as sinistral and dextral strike-slip displacements. It should be noted that the regional and local major deformation zones, although the majority have a ductile precursor, are mainly brittle in character. The focussed volume is transected by a series of smaller deformation zones with a variety of orientations and with dips varying from sub-vertical to sub

Intratumor and Intertumor Heterogeneity in Melanoma

Directory of Open Access Journals (Sweden)

Tomasz M. Grzywa

2017-12-01

Full Text Available Melanoma is a cancer that exhibits one of the most aggressive and heterogeneous features. The incidence rate escalates. A high number of clones harboring various mutations contribute to an exceptional level of intratumor heterogeneity of melanoma. It also refers to metastases which may originate from different subclones of primary lesion. Such component of the neoplasm biology is termed intertumor and intratumor heterogeneity. These levels of tumor heterogeneity hinder accurate diagnosis and effective treatment. The increasing number of research on the topic reflects the need for understanding limitation or failure of contemporary therapies. Majority of analyses concentrate on mutations in cancer-related genes. Novel high-throughput techniques reveal even higher degree of variations within a lesion. Consolidation of theories and researches indicates new routes for treatment options such as targets for immunotherapy. The demand for personalized approach in melanoma treatment requires extensive knowledge on intratumor and intertumor heterogeneity on the level of genome, transcriptome/proteome, and epigenome. Thus, achievements in exploration of melanoma variety are described in details. Particularly, the issue of tumor heterogeneity or homogeneity given BRAF mutations is discussed.

The Oligocene carbonate platform of the Zagros Basin, SW Iran: An assessment of highly-complex geological heritage

Science.gov (United States)

Habibi, Tahereh; Ruban, Dmitry A.

2017-05-01

North Africa and the Middle East possess rich geological heritage, but the latter is yet to be fully identified and described. The Oligocene carbonate platform of the Zagros Basin in southwest Iran, which corresponds to the lower part of the Asmari Formation, has significant potential for geoconservation and geotourism. The types of the geological heritage, their value, and the possible geosites have been assessed. The studied deposits are interesting because of lithology (carbonate rocks), fossils (larger foraminifera, other microfossils, diverse marine invertebrates, fish microremains, and trace fossils), biostratigraphical developments, facies (homoclinal carbonate ramp) and signature of global events (glacioeustatic fluctuations), and outstanding hydrocarbon resources. The five main geological heritage types are sedimentary, palaeontological, stratigraphical, palaeogeographical, and economical, from which the palaeontological, palaeogeographical, and economical types are of global rank. The Khollar and Kavar sections in the Fars Province of Iran are recommended as geosites suitable for research, education, and tourism. The high complexity of the geological heritage linked to the Oligocene carbonate platform of the Zagros Basin implies the phenomenon of geodiversity should be understood with regard to the relationships between types and their values.

Effect of temperature and density fluctuations on the spatially heterogeneous dynamics of glass-forming Van der Waals liquids under high pressure.

Science.gov (United States)

Koperwas, K; Grzybowski, A; Grzybowska, K; Wojnarowska, Z; Sokolov, A P; Paluch, M

2013-09-20

In this Letter, we show how temperature and density fluctuations affect the spatially heterogeneous dynamics at ambient and elevated pressures. By using high-pressure experimental data for van der Waals liquids, we examine contributions of the temperature and density fluctuations to the dynamics heterogeneity. We show that the dynamic heterogeneity decreases significantly with increasing pressure at a constant structural relaxation time (isochronal condition), while the broadening of the relaxation spectrum remains constant. This observation questions the relationship between spectral broadening and dynamic heterogeneity.

On ocean island geological repository - a second-generation option for disposal of spent fuel and high-level waste

International Nuclear Information System (INIS)

Forsberg, C.W.

1993-01-01

The concept of an ocean subseabed geological high-level waste repository with access via an ocean island is discussed. The technical advantages include, in addition to geologic waste isolation, geographical isolation, near-zero groundwater flow through the disposal site, and near-infinite ocean dilution as a backup in the event of a failure of the repository geological waste isolation system. The institutional advantages may include reduced siting problems and the potential of creating an international waste repository. Establishment of a repository accepting wastes from many countries would allow cost sharing, aid international nonproliferation goals, and ensure proper disposal of spent fuel from developing countries. Major uncertainties that are identified in this concept are the uncertainties in rock conditions at waste disposal depths, costs, and ill-defined institutional issues

Characterizing Structural and Stratigraphic Heterogeneities in a Faulted Aquifer Using Pump Tests with an Array of Westbay Multilevel Monitoring Wells

Science.gov (United States)

Johnson, B.; Zhurina, E. N.

2001-12-01

We are developing and assessing field testing and analysis methodologies for quantitative characterization of aquifer heterogenities using data measured in an array of multilevel monitoring wells (MLW) during pumping and recovery well tests. We have developed a unique field laboratory to determine the permeability field in a 20m by 40m by 70m volume in the fault partitioned, siliciclastic Hickory aquifer system in central Texas. The site incorporates both stratigraphic variations and a normal fault system that partially offsets the aquifer and impedes cross-fault flow. We constructed a high-resolution geologic model of the site based upon 1050 m of core and a suite of geophysical logs from eleven, closely spaced (3-10m), continuously cored boreholes to depths of 125 m. Westbay multilevel monitoring systems installed in eight holes provide 94 hydraulically isolated measurement zones and 25 injection zones. A good geologic model is critical to proper installation of the MLW. Packers are positioned at all significant fault piercements and selected, laterally extensive, clay-rich strata. Packers in adjacent MLW bracket selected hydrostratigraphic intervals. Pump tests utilized two, uncased, fully penetrating irrigation wells that straddle the fault system and are in close proximity (7 to 65 m) to the MLW. Pumping and recovery transient pressure histories were measured in 85 zones using pressure transducers with a resolution of 55 Pa (0.008 psi). The hydraulic response is that of an anisotropic, unconfined aquifer. The transient pressure histories vary significantly from zone to zone in a single MLW as well as between adjacent MLW. Derivative plots are especially useful for differentiating details of pressure histories. Based on the geologic model, the derivative curve of a zone reflects its absolute vertical position, vertical stratigraphic position, and proximity to either a fault or significant stratigraphic heterogeneity. Additional forward modeling is needed to

The effects of actinide separation on the radiological consequences of geologic disposal of high-level waste

International Nuclear Information System (INIS)

Hill, M.D.; White, I.F.; Fleishman, A.B.

1980-01-01

It has often been suggested that the potential hazard to man from the disposal of high-level radioactive waste could be reduced by removing a substantial fraction of the actinide elements. In this report the effects of actinide separation on the radiological consequences of one of the disposal options currently under consideration, that of burial in deep geologic formations, are examined. The results show that the potential radiological impact of geologic disposal of high-level waste arises from both long-lived fission products and actinides (and their daughter radionuclides). Neither class of radionuclides is of overriding importance and actinide separation would therefore reduce the radiological impact to only a limited extent and over limited periods. There might be a case for attempting to reduce doses from 237 Np. To achieve this it appears to be necessary to separate both neptunium and its precursor element americium. However, there are major uncertainties in the data needed to predict doses from 237 Np; further research is required to resolve these uncertainties. In addition, consideration should be given to alternative methods of reducing the radiological impact of geologic disposal. The conclusions of this assessment differ considerably from those of similar studies based on the concept of toxicity indices. Use of these indices can lead to incorrect allocation of research and development effort. (author)

A Rock Mechanics and Coupled Hydro mechanical Analysis of Geological Repository of High Level Nuclear Waste in Fractured Rocks

International Nuclear Information System (INIS)

Min, Kibok

2011-01-01

This paper introduces a few case studies on fractured hard rock based on geological data from Sweden, Korea is one of a few countries where crystalline rock is the most promising rock formation as a candidate site of geological repository of high level nuclear waste. Despite the progress made in the area of rock mechanics and coupled hydro mechanics, extensive site specific study on multiple candidate sites is essential in order to choose the optimal site. For many countries concerned about the safe isolation of nuclear wastes from the biosphere, disposal in a deep geological formation is considered an attractive option. In geological repository, thermal loading continuously disturbs the repository system in addition to disturbances a recent development in rock mechanics and coupled hydro mechanical study using DFN(Discrete Fracture Network) - DEM(Discrete Element Method) approach mainly applied in hard, crystalline rock containing numerous fracture which are main sources of deformation and groundwater flow

Monte Carlo simulation of radioactive contaminant transport in fractured geologic media: Disorder and long-range correlations

International Nuclear Information System (INIS)

Mukhopadhyay, S.; Cushman, J.H.

1997-01-01

The geologic media near Yucca mountain site consist of fractured welded tuffs along with less fractured unwelded tuff. Numerical simulation of flow and transport in such media poses a number of challenging problems, due mainly to the heterogeneities and disorder in the media. In addition, because of different dominant transport mechanisms in different regions of the media, investigations need to be carried out at different time-scales. Time-marching will pose a considerable problem in analyzing such multi-scale transient problems. The authors develop a field-scale network model of fractures and study transport of radionuclides through geologic media as a function of disorder and correlated fracture-permeabilities

Synthetic geology - Exploring the "what if?" in geology

Science.gov (United States)

Klump, J. F.; Robertson, J.

2015-12-01

The spatial and temporal extent of geological phenomena makes experiments in geology difficult to conduct, if not entirely impossible and collection of data is laborious and expensive - so expensive that most of the time we cannot test a hypothesis. The aim, in many cases, is to gather enough data to build a predictive geological model. Even in a mine, where data are abundant, a model remains incomplete because the information at the level of a blasting block is two orders of magnitude larger than the sample from a drill core, and we have to take measurement errors into account. So, what confidence can we have in a model based on sparse data, uncertainties and measurement error? Synthetic geology does not attempt to model the real world in terms of geological processes with all their uncertainties, rather it offers an artificial geological data source with fully known properties. On the basis of this artificial geology, we can simulate geological sampling by established or future technologies to study the resulting dataset. Conducting these experiments in silico removes the constraints of testing in the field or in production, and provides us with a known ground-truth against which the steps in a data analysis and integration workflow can be validated.Real-time simulation of data sources can be used to investigate crucial questions such as the potential information gain from future sensing capabilities, or from new sampling strategies, or the combination of both, and it enables us to test many "what if?" questions, both in geology and in data engineering. What would we be able to see if we could obtain data at higher resolution? How would real-time data analysis change sampling strategies? Does our data infrastructure handle many new real-time data streams? What feature engineering can be deducted for machine learning approaches? By providing a 'data sandbox' able to scale to realistic geological scenarios we hope to start answering some of these questions.

Stochastic models of solute transport in highly heterogeneous geologic media

Energy Technology Data Exchange (ETDEWEB)

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.

Gravity derived depth to basement in Santiago Basin, Chile: implications for its geological evolution, hydrogeology, low enthalpy geothermal, soil characterization and geo-hazards

OpenAIRE

Yáñez, Gonzalo; Muñoz, Mauricio; Flores-Aqueveque, Valentina; Bosch, Andrés

2015-01-01

A recording of 1,115 gravimetric stations, the review of 368 wells, and the petrophysics measurements of 106 samples from representative outcrops have been used for a comprehensive geological/geophysical study of Santiago Basin. 2.5D and 3D gravimetric modeling, constrained by regional geology, soil and bedrock densities, edge-basin outcrops, depth (minimum) to basement from wells, and detailed modeling of heterogeneous bedrock and midcrustal blocks, provided a well-constrained depth to basem...

Green heterogeneous wireless networks

CERN Document Server

Ismail, Muhammad; Nee, Hans-Peter; Qaraqe, Khalid A; Serpedin, Erchin

2016-01-01

This book focuses on the emerging research topic "green (energy efficient) wireless networks" which has drawn huge attention recently from both academia and industry. This topic is highly motivated due to important environmental, financial, and quality-of-experience (QoE) considerations. Specifically, the high energy consumption of the wireless networks manifests in approximately 2% of all CO2 emissions worldwide. This book presents the authors’ visions and solutions for deployment of energy efficient (green) heterogeneous wireless communication networks. The book consists of three major parts. The first part provides an introduction to the "green networks" concept, the second part targets the green multi-homing resource allocation problem, and the third chapter presents a novel deployment of device-to-device (D2D) communications and its successful integration in Heterogeneous Networks (HetNets). The book is novel in that it specifically targets green networking in a heterogeneous wireless medium, which re...

Intratumor and Intertumor Heterogeneity in Melanoma.

Science.gov (United States)

Grzywa, Tomasz M; Paskal, Wiktor; Włodarski, Paweł K

2017-12-01

Melanoma is a cancer that exhibits one of the most aggressive and heterogeneous features. The incidence rate escalates. A high number of clones harboring various mutations contribute to an exceptional level of intratumor heterogeneity of melanoma. It also refers to metastases which may originate from different subclones of primary lesion. Such component of the neoplasm biology is termed intertumor and intratumor heterogeneity. These levels of tumor heterogeneity hinder accurate diagnosis and effective treatment. The increasing number of research on the topic reflects the need for understanding limitation or failure of contemporary therapies. Majority of analyses concentrate on mutations in cancer-related genes. Novel high-throughput techniques reveal even higher degree of variations within a lesion. Consolidation of theories and researches indicates new routes for treatment options such as targets for immunotherapy. The demand for personalized approach in melanoma treatment requires extensive knowledge on intratumor and intertumor heterogeneity on the level of genome, transcriptome/proteome, and epigenome. Thus, achievements in exploration of melanoma variety are described in details. Particularly, the issue of tumor heterogeneity or homogeneity given BRAF mutations is discussed. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Geomass: geological modelling analysis and simulation software for the characterisation of fractured hard rock environments

International Nuclear Information System (INIS)

White, M.J.; Humm, J.P.; Todaka, N.; Takeuchi, S.

1998-01-01

This paper presents the development and functionality of a suite of applications which are being developed to support the geological investigations in the Tono URL. GEOMASS will include 3D geological modelling, 3D fluid flow and solute transport and 3D visualisation capabilities. The 3D geological modelling in GEOMASS will be undertaken using a commercially available 3D geological modelling system, EarthVision. EarthVision provides 3D mapping, interpolation, analysis and well planning software. It is being used in the GEOMASS system to provide the geological framework (structure of the tectonic faults and stratigraphic and lithological contacts) to the 3D flow code. It is also being used to gather the geological data into a standard format for use throughout the investigation programme. The 3D flow solver to be used in GEOMASS is called Frac-Affinity. Frac-Affinity models the 3D geometry of the flow system as a hybrid medium, in which the rock contains both permeable, intact rock and fractures. Frac-Affinity also performs interpolation of heterogeneous rock mass property data using a fractal based approach and the generation of stochastic fracture networks. The code solves for transient flow over a user defined sub-region of the geological framework supplied by EarthVision. The results from Frac-Affinity are passed back to EarthVision so that the flow simulation can be visualized alongside the geological structure. This work-flow allows rapid assessment of the role of geological features in controlling flow. This paper will present the concepts and approach of GEOMASS and illustrate the practical application of GEOMASS using data from Tono

Heat transfer analysis of the geologic disposal of spent fuel and high-level waste storage canisters

International Nuclear Information System (INIS)

Allen, G.K.

1980-08-01

Near-field temperatures resulting from the storage of high-level waste canisters and spent unreprocessed fuel assembly canisters in geologic formations were determined. Preliminary design of the repository was modeled for a heat transfer computer code, HEATING5, which used the Crank-Nicolson finite difference method to evaluate transient heat transfer. The heat transfer system was evaluated with several two- and three-dimensional models which transfer heat by a combination of conduction, natural convention, and radiation. Physical properties of the materials in the model were based upon experimental values for the various geologic formations. The effects of canister spacing, fuel age, and use of an overpack were studied for the analysis of the spent fuel canisters; salt, granite, and basalt were considered as the storage media for spent fuel canisters. The effects of canister diameter and use of an overpack were studied for the analysis of the high-level waste canisters; salt was considered as the only storage media for high-level waste canisters. Results of the studies on spent fuel assembly canisters showed that the canisters could be stored in salt formations with a maximum heat loading of 134 kw/acre without exceeding the temperature limits set for salt stability. The use of an overpack had little effect on the peak canister temperatures. When the total heat load per acre decreased, the peak temperatures reached in the geologic formations decreased; however, the time to reach the peak temperatures increased. Results of the studies on high-level waste canisters showed that an increased canister diameter will increase the canister interior temperatures considerably; at a constant areal heat loading, a 381 mm diameter canister reached almost a 50 0 C higher temperature than a 305 mm diameter canister. An overpacked canister caused almost a 30 0 C temperature rise in either case

Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. Introductory part and summaries

International Nuclear Information System (INIS)

1999-11-01

Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the geological disposal concept for high-level radioactive wastes (HLW) in Japan and comprises seven chapters. Chapter I briefly describes the importance of HLW management in promoting nuclear energy utilization. According to the long-term program, the HLW separated from spent fuels at reprocessing plants is to be vitrified and stored for a period of 30 to 50 years to allow cooling, then be disposed of in a deep geological formation. Chapter II mainly explains the concepts of geological disposal in Japan. Chapters III to V are devoted to discussions on three important technical elements (the geological environment of Japan, engineering technology and safety assessment of the geological disposal system) which are necessary for reliable realization of the geological disposal concept. Chapter VI demonstrates the technical ground for site selection and for setup of safety standards of the disposal. Chapter VII summarizes together with plans for future research and development. (Ohno, S.)

High Resolution Geological Site Characterization Utilizing Ground Motion Data

Science.gov (United States)

1992-06-26

rough near a service road, in low velocity, unsaturated, unconsolidated 7 sands. Other than native grass, there was no significant vegetation . Surface...literature, demonstrate slll kale field tests. Similar degrees of spatial variability in ground that these stochastic geologic effects pose a potentially

Medical Geology: a globally emerging discipline

Energy Technology Data Exchange (ETDEWEB)

Bunnell, J.E.; Finkelman, R.B.; Centeno, J.A.; Selinus, O. [Armed Forces Institute of Pathology, Washington, DC (United States)

2007-07-01

Medical Geology, the study of the impacts of geologic materials and processes on animal and human health, is a dynamic emerging discipline bringing together the geoscience, biomedical, and public health communities to solve a wide range of environmental health problems. Among the Medical Geology described in this review are examples of both deficiency and toxicity of trace element exposure. Goiter is a widespread and potentially serious health problem caused by deficiency of iodine. In many locations the deficiency is attributable to low concentrations of iodine in the bedrock. Similarly, deficiency of selenium in the soil has been cited as the principal cause of juvenile cardiomyopathy and muscular abnormalities. Overexposure to arsenic is one of the most widespread Medical Geology problems affecting more than one hundred million people in Bangladesh, India, China, Europe, Africa and North and South America. The arsenic exposure is primarily due to naturally high levels in groundwater but combustion of mineralized coal has also caused arsenic poisoning. Dental and skeletal fluorosis also impacts the health of millions of people around the world and, like arsenic, is due to naturally high concentrations in drinking water and, to a lesser extent, coal combustion. Other Medical Geology issues described include geophagia, the deliberate ingestion of soil, exposure to radon, and ingestion of high concentrations of organic compounds in drinking water. Geoscience and biomedical/public health researchers are teaming to help mitigate these health problems as well as various non-traditional issues for geoscientists such as vector-borne diseases.

How to Recharge a Confined Aquifer: An Exploration of Geologic Controls on Groundwater Storage.

Science.gov (United States)

Maples, S.; Fogg, G. E.; Maxwell, R. M.; Liu, Y.

2017-12-01

Decreased snowpack storage and groundwater overdraft in California has increased interest in managed aquifer recharge (MAR) of excess winter runoff to the Central Valley aquifer system, which has unused storage capacity that far exceeds the state's surface reservoirs. Recharge to the productive, confined aquifer system remains a challenge due to the presence of nearly-ubiquitous, multiple silt and clay confining units that limit recharge pathways. However, previous studies have identified interconnected networks of sand and gravel deposits that bypass the confining units and accommodate rapid, high-volume recharge to the confined aquifer system in select locations. We use the variably-saturated, fully-integrated groundwater/surface-water flow code, ParFlow, in combination with a high-resolution, transition probability Markov-chain geostatistical model of the subsurface geologic heterogeneity of the east side of the Sacramento Valley, CA, to characterize recharge potential across a landscape that includes these geologic features. Multiple 180-day MAR simulations show that recharge potential is highly dependent on subsurface geologic structure, with a several order-of-magnitude range of recharge rates and volumes across the landscape. Where there are recharge pathways to the productive confined-aquifer system, pressure propagation in the confined system is widespread and rapid, with multi-kilometer lateral pressure propagation. Although widespread pressure propagation occurs in the confined system, only a small fraction of recharge volume is accommodated there. Instead, the majority of recharge occurs by filling unsaturated pore spaces. Where they outcrop at land surface, high-K recharge pathways fill rapidly, accommodating the majority of recharge during early time. However, these features become saturated quickly, and somewhat counterintuitively, the low-K silt and clay facies accommodate the majority of recharge volume during most of the simulation. These findings

Heterogeneous Monolithic Integration of Single-Crystal Organic Materials.

Science.gov (United States)

Park, Kyung Sun; Baek, Jangmi; Park, Yoonkyung; Lee, Lynn; Hyon, Jinho; Koo Lee, Yong-Eun; Shrestha, Nabeen K; Kang, Youngjong; Sung, Myung Mo

2017-02-01

Manufacturing high-performance organic electronic circuits requires the effective heterogeneous integration of different nanoscale organic materials with uniform morphology and high crystallinity in a desired arrangement. In particular, the development of high-performance organic electronic and optoelectronic devices relies on high-quality single crystals that show optimal intrinsic charge-transport properties and electrical performance. Moreover, the heterogeneous integration of organic materials on a single substrate in a monolithic way is highly demanded for the production of fundamental organic electronic components as well as complex integrated circuits. Many of the various methods that have been designed to pattern multiple heterogeneous organic materials on a substrate and the heterogeneous integration of organic single crystals with their crystal growth are described here. Critical issues that have been encountered in the development of high-performance organic integrated electronics are also addressed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Energy Technology Data Exchange (ETDEWEB)

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

Quantification of oil recovery efficiency, CO 2 storage potential, and fluid-rock interactions by CWI in heterogeneous sandstone oil reservoirs

DEFF Research Database (Denmark)

Seyyedi, Mojtaba; Sohrabi, Mehran; Sisson, Adam

2017-01-01

Significant interest exists in improving recovery from oil reservoirs while addressing concerns about increasing CO2 concentrations in the atmosphere. The combination of Enhanced Oil Recovery (EOR) and safe geologic storage of CO2 in oil reservoirs is appealing and can be achieved by carbonated (CO...... for oil recovery and CO2 storage potential on heterogeneous cores. Since not all the oil reservoirs are homogenous, understanding the potential of CWI as an integrated EOR and CO2 storage scenario in heterogeneous oil reservoirs is essential....

Heterogeneous Single-Atom Catalyst for Visible-Light-Driven High-Turnover CO2 Reduction: The Role of Electron Transfer.

Science.gov (United States)

Gao, Chao; Chen, Shuangming; Wang, Ying; Wang, Jiawen; Zheng, Xusheng; Zhu, Junfa; Song, Li; Zhang, Wenkai; Xiong, Yujie

2018-03-01

Visible-light-driven conversion of CO 2 into chemical fuels is an intriguing approach to address the energy and environmental challenges. In principle, light harvesting and catalytic reactions can be both optimized by combining the merits of homogeneous and heterogeneous photocatalysts; however, the efficiency of charge transfer between light absorbers and catalytic sites is often too low to limit the overall photocatalytic performance. In this communication, it is reported that the single-atom Co sites coordinated on the partially oxidized graphene nanosheets can serve as a highly active and durable heterogeneous catalyst for CO 2 conversion, wherein the graphene bridges homogeneous light absorbers with single-atom catalytic sites for the efficient transfer of photoexcited electrons. As a result, the turnover number for CO production reaches a high value of 678 with an unprecedented turnover frequency of 3.77 min -1 , superior to those obtained with the state-of-the-art heterogeneous photocatalysts. This work provides fresh insights into the design of catalytic sites toward photocatalytic CO 2 conversion from the angle of single-atom catalysis and highlights the role of charge kinetics in bridging the gap between heterogeneous and homogeneous photocatalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Methodology of safety assessment and sensitivity analysis for geologic disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Kimura, Hideo; Takahashi, Tomoyuki; Shima, Shigeki; Matsuzuru, Hideo

1995-01-01

A deterministic safety assessment methodology has been developed to evaluate long-term radiological consequences associated with geologic disposal of high-level radioactive waste, and to demonstrate a generic feasibility of geologic disposal. An exposure scenario considered here is based on a normal evolution scenario which excludes events attributable to probabilistic alterations in the environment. A computer code system GSRW thus developed is based on a non site-specific model, and consists of a set of sub-modules for calculating the release of radionuclides from engineered barriers, the transport of radionuclides in and through the geosphere, the behavior of radionuclides in the biosphere, and radiation exposures of the public. In order to identify the important parameters of the assessment models, an automated procedure for sensitivity analysis based on the Differential Algebra method has been developed to apply to the GSRW. (author)

Quantitative aspects of highly emanating geologic materials and their role in creating high indoor radon. Final report, April 1, 1994--March 31, 1996

International Nuclear Information System (INIS)

Gundersen, L.C.S.; Schumann, R.R.; Gates, A.E.; Price, P.

1996-01-01

Indoor radon hot spots, areas where indoor radon commonly exceeds 20 pCi/L, are often caused by unusually highly emanating soils or rock and their interaction with ambient climatic conditions and a building's architecture. Highly emanating soils and rocks include glacial deposits; dry fractured clays; black shales; limestone-derived soils; karst and cave areas, fractured or sheared granitic crystalline rocks; mine tailings; uraniferous backfill; and most uranium deposits. The above list probably accounts for 90% of the Nation's indoor radon over 20 pCi/L. In several of these high indoor radon areas, there appears to be a link between the nature of the radon source in the ground, the architecture of the home, and the relative magnitude and ease of mitigation of the indoor air problem. Quantification of geologic materials in terms of their radon potential with respect to climatic and architectural considerations has never been accomplished. Recent studies have attempted semi-quantitative rankings but rigorous analysis has not been done. In this investigation the authors have attempted to develop the quantitative aspects of geologic materials for prediction of very high indoor radon at several scales of observation from national to census tract

Impacts of new developments in partitioning and transmutation on the disposal of high-level nuclear waste in a mined geologic repository

International Nuclear Information System (INIS)

Ramspott, L.D.; Jor-Shan Choi; Halsey, W.; Pasternak, A.; Cotton, T.; Burns, J.; McCabe, A.; Colglazier, W.; Lee, W.W.L.

1992-03-01

During the 1970s, the United States and other countries thoroughly evaluated the options for the safe and final disposal of high-level radioactive wastes (HLW). The worldwide scientific community concluded that deep geologic disposal was clearly the most technically feasible alternative. They also ranked the partitioning and transmutation (P-T) of radionuclides among the least favored options. A 1982 report by the International Atomic Energy Agency summarized the key reasons for that ranking: ''Since the long-term hazards are already low, there is little incentive to reduce them further by P-T. Indeed the incremental costs of introducing P-T appear to be unduly high in relation to the prospective benefits.'' Recently, the delays encountered by the US geologic disposal program for HLW, along with advanced in the development of P-T concepts, have led some to propose P-T as a means of reducing the long-term risks from the radioactive wastes that require disposal and thus making it easier to site, license, and build a geologic repository. This study examines and evaluates the effects that introducing P-T would have on the US geologic disposal program

Foliation: Geological background, rock mechanics significance, and preliminary investigations at Olkiluoto

International Nuclear Information System (INIS)

Milnes, A.G.; Hudson, J.; Wikstroem, L.; Aaltonen, I.

2006-01-01

A well developed, pervasive foliation is a characteristic feature of the migmatites and gneisses in the Olkiluoto bedrock, and is expected to have a significant influence on the underground construction, the design and layout and the groundwater flow regime of a deep spent nuclear fuel repository. This Working Report reviews the geological background and rock mechanics significance of foliation, and develops a methodology for the systematic acquisition of foliation data in cored boreholes and in tunnels at the Olkiluoto site, to provide the necessary basis for future geological, rock mechanics and hydrogeological modelling. The first part of the methodology concerns foliation characterisation, and develops a characterisation scheme based on two variables: the foliation type (G = gneissic, B = banded, S = schistose), which is a function of mineral composition and degree of smallscale heterogeneity, and the foliation intensity (1 = low, 2 = intermediate, 3 = high), which is a function of the type and intensity of the deformation by which it was produced (under high-grade metamorphic conditions in the core of the Svecofennian orogenic belt). At the suggested reference scales (1 m length of core, 10 m 2 area of tunnel wall), the most representative foliation type and intensity is assessed using a standard set of core photographs, which are included as an Appendix at the end of the report, providing a systematic description in terms of 9 descriptive types (G1, G2, G3, B1, B2, B3, S1, S2, S3). As a further step, the rock mechanics significance of these types is assessed and a rock mechanics foliation (RMF) number is assigned (RMF 0 = no significance, RMF 1, RMF 2 and RMF 3 = low, intermediate and high significance, respectively). The second part of the methodology concerns the orientations of the foliation within the same 1 m core lengths or 10 m2 wall areas, which have been characterised as above. This combined analysis of foliation character and foliation orientation

Recharge heterogeneity and high intensity rainfall events increase contamination risk for Mediterranean groundwater resources

Science.gov (United States)

Hartmann, Andreas; Jasechko, Scott; Gleeson, Tom; Wada, Yoshihide; Andreo, Bartolomé; Barberá, Juan Antonio; Brielmann, Heike; Charlier, Jean-Baptiste; Darling, George; Filippini, Maria; Garvelmann, Jakob; Goldscheider, Nico; Kralik, Martin; Kunstmann, Harald; Ladouche, Bernard; Lange, Jens; Mudarra, Matías; Francisco Martín, José; Rimmer, Alon; Sanchez, Damián; Stumpp, Christine; Wagener, Thorsten

2017-04-01

Karst develops through the dissolution of carbonate rock and results in pronounced spatiotemporal heterogeneity of hydrological processes. Karst groundwater in Europe is a major source of fresh water contributing up to half of the total drinking water supply in some countries like Austria or Slovenia. Previous work showed that karstic recharge processes enhance and alter the sensitivity of recharge to climate variability. The enhanced preferential flow from the surface to the aquifer may be followed by enhanced risk of groundwater contamination. In this study we assess the contamination risk of karst aquifers over Europe and the Mediterranean using simulated transit time distributions. Using a new type of semi-distributed model that considers the spatial heterogeneity of karst hydraulic properties, we were able to simulate karstic groundwater recharge including its heterogeneous spatiotemporal dynamics. The model is driven by gridded daily climate data from the Global Land Data Assimilation System (GLDAS). Transit time distributions are calculated using virtual tracer experiments. We evaluated our simulations by independent information on transit times derived from observed time series of water isotopes of >70 karst springs over Europe. The simulations indicate that, compared to humid, mountain and desert regions, the Mediterranean region shows a stronger risk of contamination in Europe because preferential flow processes are most pronounced given thin soil layers and the seasonal abundance of high intensity rainfall events in autumn and winter. Our modelling approach includes strong simplifications and its results cannot easily be generalized but it still highlights that the combined effects of variable climate and heterogeneous catchment properties constitute a strong risk on water quality.

High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

Directory of Open Access Journals (Sweden)

R. Wagner

2010-08-01

Full Text Available The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario

High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

Science.gov (United States)

Wagner, R.; Möhler, O.; Saathoff, H.; Schnaiter, M.; Leisner, T.

2010-08-01

The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers

The basic concept for the geological surveys

International Nuclear Information System (INIS)

Deguchi, Akira; Takahashi, Yoshiaki

1998-01-01

Before the construction of high level radioactive waste repository, the implementing entity will go through three siting stages for the repository. In each of those three stages, the implementing entity will carry out geological surveys. In this report, the concept for the geological surveys is described, on the basic of 'The policies for the high level radioactive waste disposal (a tentative draft)' issued by the Atomic Energy Commission in July, 1997. (author)

Geological Geophysical and structural studies in Mina Ratones (Pluton de Albala); Estudios geologico-estructurales y geofisicos en Mina Ratones (Pluton de Albala)

Energy Technology Data Exchange (ETDEWEB)

Perez-Estaun, A; Carbonell, R; Marti, D; Flecha, I [Instituto de Ciencias de la Tierra Jaume Almera. Barcelona (Spain); Escuder Viruete, J [Universidad complutense de Madrid. Madrid (Spain)

2002-07-01

Mina Ratones environmental restoration project included petrological, structural,geophysical, hydrogeological and hydrogeochemical studies. The main objective of the geologic-structural and geophysical studies was the Albala granite structural characterization around the Mina Ratones uranium mine. The location of facies, fault zones (faults and dykes) as well as the distribution of some physical properties inside the rock massif was obtained for a granitic black of 900, 500, and 500 m. The geologic-structural and geophysical techniques applied to Mina Ratones provided a multidisciplinary approach for high resolution characterization of rock massif, and the structures potentially containing fluids,able to be applied to the hydrogeological modelling to a particular area. Geological studies included a detailed structural mapping of the area surrounding the mine (1:5,000 scale), the geometric, kinematics, and dynamics analysis of fractures of all scales, the petrology and geochemistry of fault rocks and altered areas surrounding fractures, and the microstructural studies of samples from surface and core lags. The construction of geostatistical models in two and three dimensions had helped to characterize the Mina Ratones rock massif showing the spatial distribution of fault zones, fracture intensity, granite composition heterogeneities, fluid-rock interaction zones, and physical properties. (Author)

Geologic isolation of nuclear waste at high latitudes: the role of ice sheets

Science.gov (United States)

Person, M.; McIntosh, J.; Iverson, N.; Neuzil, C.E.; Bense, V.

2012-01-01

Geologic isolation of high-level nuclear waste from the biosphere requires special consideration in countries at high latitudes (>40°N) owing to the possibility of future episodes of continental glaciation (Talbot 1999). It is now widely recognized that Pleistocene continental glaciations have had a profound effect on rates of sediment erosion (Cuffey & Paterson 2010) and deformation including tectonic thrusting (Pedersen 2005) as well as groundwater flow (Person et al. 2007; Lemieux et al. 2008a,b,c). In addition, glacial mechanical loads may have generated anomalous, or fossil, pore pressures within certain clay-rich confining units (e.g. Vinard et al. 2001). Because high-level nuclear wastes must be isolated from the biosphere as long as 1 million years (McMurry et al. 2003), the likelihood of one or more continental ice sheets overrunning high-latitude sites must be considered.

Siting, design and construction of a deep geological repository for the disposal of high level and alpha bearing wastes

International Nuclear Information System (INIS)

1990-06-01

The main objective of this document is to summarize the basic principles and approaches to siting, design and construction of a deep geological repository for disposal of high level and alpha bearing radioactive wastes, as commonly agreed upon by Member States. This report is addressed to decision makers and technical managers as well as to specialists planning for siting, design and construction of geological repositories for disposal of high level and alpha bearing wastes. This document is intended to provide Member States of the IAEA with a summary outline for the responsible implementing organizations to use for siting, designing and constructing confinement systems for high level and alpha bearing radioactive waste in accordance with the protection objectives set by national regulating authorities or derived from safety fundamentals and standards of the IAEA. The protection objectives will be achieved by the isolation of the radionuclides from the environment by a repository system, which consists of a series of man made and natural safety barriers. Engineered barriers are used to enhance natural geological containment in a variety of ways. They must complement the natural barriers to provide adequate safety and necessary redundancy to the barrier system to ensure that safety standards are met. Because of the long timescales involved and the important role of the natural barrier formed by the host rock, the site selection process is a key activity in the repository design and development programme. The choice of the site, the investigation of its geological setting, the exploration of the regional hydrogeological setting and the primary underground excavations are all considered to be part of the siting process. 16 refs

Bridging nuclear safety, security and safeguards at geological disposl of high level radioactive waste and spent nuclear fuel

International Nuclear Information System (INIS)

Niemeyer, Irmgard; Deissmann, Guido; Bosbach, Dirk

2016-01-01

Findings and recommendations: • Further R&D needed to identify concepts, methods and technologies that would be best suited for the holistic consideration of safety, security and safeguards provisions of geological disposal. • 3S ‘toolbox’, including concepts, methods and technologies for: ■ material accountancy, ■ measurement techniques for spent fuel verification, ■ containment and surveillance, ■ analysis of open source information, ■ environmental sampling and monitoring, ■ continuity of knowledge, ■ design implications. •: Bridging safety, security and safeguards in research funding and research activities related to geological disposal of high-level radioactive waste and spent nuclear fuel.

Deep geological disposal research in Argentina

International Nuclear Information System (INIS)

Ninci Martinez, Carlos A.; Ferreyra, Raul E.; Vullien, Alicia R.; Elena, Oscar; Lopez, Luis E.; Maloberti, Alejandro; Nievas, Humberto O.; Reyes, Nancy C.; Zarco, Juan J.; Bevilacqua, Arturo M.; Maset, Elvira R.; Jolivet, Luis A.

2001-01-01

Argentina shall require a deep geological repository for the final disposal of radioactive wastes, mainly high-level waste (HLW) and spent nuclear fuel produced at two nuclear power plants and two research reactors. In the period 1980-1990 the first part of feasibility studies and a basic engineering project for a radioactive high level waste repository were performed. From the geological point of view it was based on the study of granitic rocks. The area of Sierra del Medio, Province of Chubut, was selected to carry out detailed geological, geophysical and hydrogeological studies. Nevertheless, by the end of the eighties the project was socially rejected and CNEA decided to stop it at the beginning of the nineties. That decision was strongly linked with the little attention paid to social communication issues. Government authorities were under a strong pressure from social groups which demanded the interruption of the project, due to lack of information and the fear it generated. The lesson learned was: social communication activities shall be carried out very carefully in order to advance in the final disposal of HLW at deep geological repositories (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

Spatial heterogeneity in liquid–liquid phase transition

International Nuclear Information System (INIS)

Duan Yun-Rui; Li Tao; Wu Wei-Kang; Li Jie; Zhou Xu-Yan; Liu Si-Da; Li Hui

2017-01-01

Molecular dynamics simulations are performed to investigate the liquid–liquid phase transition (LLPT) and the spatial heterogeneity in Al–Pb monotectic alloys. The results reveal that homogeneous liquid Al–Pb alloy undergoes an LLPT, separating into Al-rich and Pb-rich domains, which is quite different from the isocompositional liquid water with a transition between low-density liquid (LDL) and high-density liquid (HDL). With spatial heterogeneity becoming large, LLPT takes place correspondingly. The relationship between the cooling rate, relaxation temperature and percentage of Al and the spatial heterogeneity is also reported. This study may throw light on the relationship between the structure heterogeneity and LLPT, which provides novel strategies to control the microstructures in the fabrication of the material with high performance. (paper)

Characterizing the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada: hydrology and geochemistry

Science.gov (United States)

Stuckless, John S.; Levich, Robert A.

2012-01-01

This hydrology and geochemistry volume is a companion volume to the 2007 Geological Society of America Memoir 199, The Geology and Climatology of Yucca Mountain and Vicinity, Southern Nevada and California, edited by Stuckless and Levich. The work in both volumes was originally reported in the U.S. Department of Energy regulatory document Yucca Mountain Site Description, for the site characterization study of Yucca Mountain, Nevada, as the proposed U.S. geologic repository for high-level radioactive waste. The selection of Yucca Mountain resulted from a nationwide search and numerous committee studies during a period of more than 40 yr. The waste, largely from commercial nuclear power reactors and the government's nuclear weapons programs, is characterized by intense penetrating radiation and high heat production, and, therefore, it must be isolated from the biosphere for tens of thousands of years. The extensive, unique, and often innovative geoscience investigations conducted at Yucca Mountain for more than 20 yr make it one of the most thoroughly studied geologic features on Earth. The results of these investigations contribute extensive knowledge to the hydrologic and geochemical aspects of radioactive waste disposal in the unsaturated zone. The science, analyses, and interpretations are important not only to Yucca Mountain, but also to the assessment of other sites or alternative processes that may be considered for waste disposal in the future. Groundwater conditions, processes, and geochemistry, especially in combination with the heat from radionuclide decay, are integral to the ability of a repository to isolate waste. Hydrology and geochemistry are discussed here in chapters on unsaturated zone hydrology, saturated zone hydrology, paleohydrology, hydrochemistry, radionuclide transport, and thermally driven coupled processes affecting long-term waste isolation. This introductory chapter reviews some of the reasons for choosing to study Yucca Mountain as a

Characterizing the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada--hydrology and geochemistry

Science.gov (United States)

Stuckless, John S.; Levich, Robert A.

2012-01-01

This hydrology and geochemistry volume is a companion volume to the 2007 Geological Society of America Memoir 199, The Geology and Climatology of Yucca Mountain and Vicinity, Southern Nevada and California, edited by Stuckless and Levich. The work in both volumes was originally reported in the U.S. Department of Energy regulatory document Yucca Mountain Site Description, for the site characterization study of Yucca Mountain, Nevada, as the proposed U.S. geologic repository for high-level radioactive waste. The selection of Yucca Mountain resulted from a nationwide search and numerous committee studies during a period of more than 40 yr. The waste, largely from commercial nuclear power reactors and the government's nuclear weapons programs, is characterized by intense penetrating radiation and high heat production, and, therefore, it must be isolated from the biosphere for tens of thousands of years. The extensive, unique, and often innovative geoscience investigations conducted at Yucca Mountain for more than 20 yr make it one of the most thoroughly studied geologic features on Earth. The results of these investigations contribute extensive knowledge to the hydrologic and geochemical aspects of radioactive waste disposal in the unsaturated zone. The science, analyses, and interpretations are important not only to Yucca Mountain, but also to the assessment of other sites or alternative processes that may be considered for waste disposal in the future. Groundwater conditions, processes, and geochemistry, especially in combination with the heat from radionuclide decay, are integral to the ability of a repository to isolate waste. Hydrology and geochemistry are discussed here in chapters on unsaturated zone hydrology, saturated zone hydrology, paleohydrology, hydrochemistry, radionuclide transport, and thermally driven coupled processes affecting long-term waste isolation. This introductory chapter reviews some of the reasons for choosing to study Yucca Mountain as a

Coquina of the Lagoa Feia formation, Campos Basin: development geology evolution; Coquinas da formacao Lagoa Feia, Bacia de Campos: evolucao da geologia de desenvolvimento

Energy Technology Data Exchange (ETDEWEB)

Baumgarten, Cleyton S; Dultra, Artur J.C.; Silva Scuta, Maximiano da; Figueiredo, Marcus V.L. de; Sequeira, Maria F.P.B. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

1988-01-01

The evolution of Lagoa Feia coquinas is analysed in its several stages, beginning with the exploratory phase. Special emphasis is devoted to the elements which contribute to improvement in geologic mapping. Development of the reservoir geology, interpretation of the factors that had influence in the reservoir pressure, communications between the fields, causing the low pressure, are discussed. The low transmissibility resultant from the heterogeneity created by the calcite and silica cementation are also reported. 11 figs., 7 refs

Nagra technical report 14-02, geological basics - Dossier III - Long-term geological developments

International Nuclear Information System (INIS)

Schnellmann, M.; Madritsch, H.

2014-01-01

This dossier is the third of a series of eight reports concerning the safety and technical aspects of locations for the disposal of radioactive wastes in Switzerland. Dossier III takes a look at long-term geological developments. Developments in the topography and river networks of northern Switzerland over the past five million years are looked at. Data and information derived from high-resolution models and compilations of gravel deposition, glacier developments and moraines are reviewed. Tectonic developments, seismological aspects and erosion are discussed. Their consequences for the long-term geological developments in the proposed depository areas are looked at

Spectral-element simulation of two-dimensional elastic wave propagation in fully heterogeneous media on a GPU cluster

Science.gov (United States)

Rudianto, Indra; Sudarmaji

2018-04-01

We present an implementation of the spectral-element method for simulation of two-dimensional elastic wave propagation in fully heterogeneous media. We have incorporated most of realistic geological features in the model, including surface topography, curved layer interfaces, and 2-D wave-speed heterogeneity. To accommodate such complexity, we use an unstructured quadrilateral meshing technique. Simulation was performed on a GPU cluster, which consists of 24 core processors Intel Xeon CPU and 4 NVIDIA Quadro graphics cards using CUDA and MPI implementation. We speed up the computation by a factor of about 5 compared to MPI only, and by a factor of about 40 compared to Serial implementation.

Are we there yet? An NSF-CAREER sponsored field program as a vehicle for engaging high school students in geology

Science.gov (United States)

Frank, T. D.

2011-12-01

Many students graduate from high school having never been exposed to the geosciences. The idea of a career in the geosciences is therefore often not on the radar when students embark on university studies. History on the Rocks, a field-based summer program developed as part of a NSF-CAREER grant and offered annually since 2008, is designed to expose high school students to geology through hands-on experiences. The program focuses on interpreting the sedimentary rock record, the major archive of Earth history. Following a day of introductory exercises in the lab, participants travel to world-class geologic sites around Nebraska and collect evidence that allows them to interpret environment and climate at the time of deposition. They use their data to consider how climate change, sea level, and catastrophic events leave their imprints on the rock record and to reconstruct Nebraska's geologic history. In 2008, 12 high school science teachers from districts across Nebraska, incuding the Santee Nation district, enrolled in the program. Teachers developed a set of lesson plans related to their field experience. They posted the plans online and now routinely use them in their home schools, thereby exposing their students to geology. Subsequent programs have been held for groups of high school students drawn from rural and urban regions throughout the state. Working with students raised some unforeseen issues related to accident liability and parental concern about students working in remote areas. These problems were solved by offering the program through existing, well-known entities, including Girls Inc., a nonprofit organization that empowers girls from low-income families in urban settings (i.e., Omaha), and the 4H Youth Development Extension Office at the University of Nebraska-Lincoln (UNL). Both groups are eager to provide students with the opportunity to visit a university and explore careers. Convincing inner-city students, who generally came to the program with

The geological attitude

International Nuclear Information System (INIS)

Fuller, J.G.C.M.

1992-01-01

This paper discusses geological activity which takes place mainly in response to industrial and social pressures. Past geological reaction to these pressures profoundly altered popular conceptions of time, the Church, man, and the balance of nature. The present-day circumstances of geology are not essentially different from those of the past. Petroleum geology in North American illustrates the role of technology in determining the style and scope of geological work. Peaks of activity cluster obviously on the introduction from time to time of new instrumental capabilities (geophysical apparatus, for example), although not infrequently such activity is testing concepts or relationships perceived long before. Organic metamorphism and continental drift provide two examples. The petroleum industry now faces the dilemma of satisfying predicted demands for fuel, without doing irreparable injury to its environment of operation. Awareness of man's place in nature, which is a fundamental perception of geology, governs the geological attitude

Preliminary assessment of the radiological protection aspects of disposal of high-level waste in geologic formations

International Nuclear Information System (INIS)

Hill, M.D; Grimwood, P.D.

1978-01-01

The purpose of this study is to carry out a preliminary assessment of the potential radiological consequences of disposing of vitrified high-level radioactive waste in geologic formations. The events which could lead to the release of radioactivity from a geologic repository are reviewed and ingress of ground-water is identified as the principal mechanism by which radioactivity may be transported back to the biosphere. A mathematical model of radionuclide migration with ground-water is used to predict possible rates of release of radioactivity into fresh water from a hypothetical repository containing all the high-level waste which may be generated in the UK up to the year 2000. The individual and collective doses which could be received as a result of man's use of contaminated fresh water are evaluated. The numerical results of the study depend very much on the assumptions made and cannot be used to draw any detailed conclusions. The main result is the identification of areas where further studies are required in order to carry out a full evaluation of this disposal option. (author)

Geological and production characteristics of strandplain/barrier island reservoirs in the United States

Energy Technology Data Exchange (ETDEWEB)

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.

Quantitative geological modeling based on probabilistic integration of geological and geophysical data

DEFF Research Database (Denmark)

Gulbrandsen, Mats Lundh

In order to obtain an adequate geological model of any kind, proper integration of geophysical data, borehole logs and geological expert knowledge is important. Geophysical data provide indirect information about geology, borehole logs provide sparse point wise direct information about geology...... entitled Smart Interpretation is developed. This semi-automatic method learns the relation between a set of data attributes extracted from deterministically inverted airborne electromagnetic data and a set of interpretations of a geological layer that is manually picked by a geological expert...

Geology of Venus

International Nuclear Information System (INIS)

Basilevsky, A.T.; Head, J.W. III.

1988-01-01

This paper summarizes the emerging picture of the surface of Venus provided by high-resolution earth-based radar telescopes and orbital radar altimetry and imaging systems. The nature and significance of the geological processes operating there are considered. The types of information needed to complete the picture are addressed. 71 references

Biofouling patterns in spacer filled channels: High resolution imaging for characterization of heterogeneous biofilms

KAUST Repository

Staal, Marc

2017-08-15

Biofilms develop in heterogeneous patterns at a µm scale up to a cm scale, and patterns become more pronounced when biofilms develop under complex hydrodynamic flow regimes. Spatially heterogeneous biofilms are especially known in spiral wound reverse osmosis (RO) and nanofiltration (NF) membrane filtration systems used for desalination and wastewater reuse to produce high quality (drinking) water. These spiral wound membrane modules contain mesh-like spacer structures used to create an intermembrane space and improve water mixing. Spacers create inhomogeneous water flow patterns resulting in zones favouring biofilm growth, possibly leading to biofouling thus hampering water production. Oxygen sensing planar optodes were used to visualize variations in oxygen decrease rates (ODR). ODR is an indication of biofilm activity. In this study, ODR images of multiple repetitive spacer areas in a membrane fouling simulator were averaged to produce high resolution, low noise ODR images. Averaging 40 individual spacer areas improved the ODR distribution image significantly and allowed comparison of biofilm patterning over a spacer structure at different positions in an RO filter. This method clearly showed that most active biofilm accumulated on and in direct vicinity of the spacer. The averaging method was also used to calculate the deviation of ODR patterning from individual spacer areas to the average ODR pattern, proposing a new approach to determine biofilm spatial heterogeneity. This study showed that the averaging method can be applied and that the improved, averaged ODR images can be used as an analytical, in-situ, non-destructive method to assess and quantify the effect of membrane installation operational parameters or different spacer geometries on biofilm development in spiral wound membrane systems characterized by complex hydrodynamic conditions.

Biosphere modeling for safety assessment to high-level radioactive waste geological disposal. Application of reference biosphere methodology to safety assesment of geological disposal

International Nuclear Information System (INIS)

Baba, Tomoko; Ishihara, Yoshinao; Ishiguro, Katsuhiko; Suzuki, Yuji; Naito, Morimasa

2000-01-01

In the safety assessment of a high-level radioactive waste disposal system, it is required to estimate future radiological impacts on human beings. Consideration of living habits and the human environment in the future involves a large degree of uncertainty. To avoid endless speculation aimed at reducing such uncertainty, an approach is applied for identifying and justifying a 'reference biosphere' for use in safety assessment in Japan. considering a wide range of Japanese geological environments, saline specific reference biospheres' were developed using an approach consistent with the BIOMOVS II reference biosphere methodology. (author)

Effects of heat from high-level waste on performance of deep geological repository components

International Nuclear Information System (INIS)

1984-11-01

This report discusses the effects of heat on the deep geological repository systems and its different components. The report is focussed specifically on effects due to thermal energy release solely from high-level waste or spent fuel. It reviews the experimental data and theoretical models of the effects of heat both on the behaviour of engineered and natural barriers. A summary of the current status of research and repository development including underground test facilities is presented

Shock interactions with heterogeneous energetic materials

Science.gov (United States)

Yarrington, Cole D.; Wixom, Ryan R.; Damm, David L.

2018-03-01

The complex physical phenomenon of shock wave interaction with material heterogeneities has significant importance and nevertheless remains little understood. In many materials, the observed macroscale response to shock loading is governed by characteristics of the microstructure. Yet, the majority of computational studies aimed at predicting phenomena affected by these processes, such as the initiation and propagation of detonation waves in explosives or shock propagation in geological materials, employ continuum material and reactive burn model treatment. In an effort to highlight the grain-scale processes that underlie the observable effects in an energetic system, a grain-scale model for hexanitrostilbene (HNS) has been developed. The measured microstructures were used to produce synthetic computational representations of the pore structure, and a density functional theory molecular dynamics derived equation of state (EOS) was used for the fully dense HNS matrix. The explicit inclusion of the microstructure along with a fully dense EOS resulted in close agreement with historical shock compression experiments. More recent experiments on the dynamic reaction threshold were also reproduced by inclusion of a global kinetics model. The complete model was shown to reproduce accurately the expected response of this heterogeneous material to shock loading. Mesoscale simulations were shown to provide a clear insight into the nature of threshold behavior and are a way to understand complex physical phenomena.

Spatial heterogeneities and variability of karst hydro-system : insights from geophysics

Science.gov (United States)

Champollion, C.; Fores, B.; Lesparre, N.; Frederic, N.

2017-12-01

Heterogeneous systems such as karsts or fractured hydro-systems are challenging for both scientist and groundwater resources management. Karsts heterogeneities prevent the comparison and moreover the combination of data representative of different scales: borehole water level can generally not be used directly to interpret spring flow dynamic for example. The spatial heterogeneity has also an impact on the temporal variability of groundwater transfer and storage. Karst hydro-systems have characteristic non linear relation between precipitation amount and discharge at the outlets with threshold effects and a large variability of groundwater transit times In the presentation, geophysical field experiments conducted in karst hydro-system in the south of France are used to investigate groundwater transfer and storage variability at a scale of a few hundred meters. We focus on the added value of both geophysical time-lapse gravity experiments and 2D ERT imaging of the subsurface heterogeneities. Both gravity and ERT results can only be interpreted with large ambiguity or some strong a priori: the relation between resistivity and water content is not unique; almost no information about the processes can be inferred from the groundwater stock variations. The present study demonstrate how the ERT and gravity field experiments can be interpreted together in a coherent scheme with less ambiguity. First the geological and hydro-meteorological context is presented. Then the ERT field experiment including the processing and the results are detailed in the section about geophysical imaging of the heterogeneities. The gravity double difference (S2D) time-lapse experiment is described in the section about geophysical monitoring of the temporal variability. The following discussion demonstrate the impact of both experiments on the interpretation in terms of processes and heterogeneities.

Status of technology for isolating high-level radioactive wastes in geologic repositories

International Nuclear Information System (INIS)

Klingsberg, C.; Duguid, J.

1980-10-01

This report attempts to summarize the status of scientific and technological knowledge relevant to long-term isolation of high-level and transuranic wastes in a mined geologic repository. It also identifies and evaluates needed information and identifies topics in which work is under way or needed to reduce uncertainties. The major findings and conclusions on the following topics are presented: importance of the systems approach; prospects for successful isolation of wastes; need for site-specific investigations; human activities in the future; importance of modelling; disposal of transuranic wastes; status of technology of isolation barriers, performance assessment, site selection and characterization, and potential host rocks

Designing shafts for handling high-level radioactive wastes in mined geologic repositories

International Nuclear Information System (INIS)

Hambley, D.F.; Morris, J.R.

1988-01-01

Waste package conceptual designs developed in the United States by the U.S. Department of Energy's Office of Civilian Radioactive Waste Management are the basis for specifying the dimensions and weights of the waste package and transfer cask combinations to be hoisted in the waste handling shafts in mined geologic repositories for high-level radioactive waste. The hoist, conveyance, counterweight, and hoist ropes are then sized. Also taken into consideration are overwind and underwind arrestors and safety features required by the U.S. Nuclear Regulatory Commission. Other design features such as braking systems, chairing system design, and hoisting speed are considered in specifying waste hoisting system parameters for example repository sites

Terrestrial analogs, planetary geology, and the nature of geological reasoning

Science.gov (United States)

Baker, Victor R.

2014-05-01

Analogical reasoning is critical to planetary geology, but its role can be misconstrued by those unfamiliar with the practice of that science. The methodological importance of analogy to geology lies in the formulation of genetic hypotheses, an absolutely essential component of geological reasoning that was either ignored or denigrated by most 20th century philosophers of science, who took the theoretical/ experimental methodology of physics to be the sole model for all of scientific inquiry. Following the seminal 19th century work of Grove Karl Gilbert, an early pioneer of planetary geology, it has long been recognized that broad experience with and understanding of terrestrial geological phenomena provide geologists with their most effective resource for the invention of potentially fruitful, working hypotheses. The actions of (1) forming such hypotheses, (2) following their consequences, and (3) testing those consequences comprise integral parts of effective geological practice in regard to the understanding of planetary surfaces. Nevertheless, the logical terminology and philosophical bases for such practice will be unfamiliar to most planetary scientists, both geologists and nongeologists. The invention of geological hypotheses involves both inductive inferences of the type Gilbert termed “empiric classification” and abductive inferences of a logical form made famous by the 19th century American logician Charles Sanders Peirce. The testing and corroboration of geological hypotheses relies less on the correspondence logic of theoretical/ experimental sciences, like physics, and more on the logic of consistency, coherence, and consilience that characterizes the investigative and historical sciences of interpretation exemplified by geology.

Health benefits of geologic materials and geologic processes

Science.gov (United States)

Finkelman, R.B.

2006-01-01

The reemerging field of Medical Geology is concerned with the impacts of geologic materials and geologic processes on animal and human health. Most medical geology research has been focused on health problems caused by excess or deficiency of trace elements, exposure to ambient dust, and on other geologically related health problems or health problems for which geoscience tools, techniques, or databases could be applied. Little, if any, attention has been focused on the beneficial health effects of rocks, minerals, and geologic processes. These beneficial effects may have been recognized as long as two million years ago and include emotional, mental, and physical health benefits. Some of the earliest known medicines were derived from rocks and minerals. For thousands of years various clays have been used as an antidote for poisons. "Terra sigillata," still in use today, may have been the first patented medicine. Many trace elements, rocks, and minerals are used today in a wide variety of pharmaceuticals and health care products. There is also a segment of society that believes in the curative and preventative properties of crystals (talismans and amulets). Metals and trace elements are being used in some of today's most sophisticated medical applications. Other recent examples of beneficial effects of geologic materials and processes include epidemiological studies in Japan that have identified a wide range of health problems (such as muscle and joint pain, hemorrhoids, burns, gout, etc.) that may be treated by one or more of nine chemically distinct types of hot springs, and a study in China indicating that residential coal combustion may be mobilizing sufficient iodine to prevent iodine deficiency disease. ?? 2006 MDPI. All rights reserved.

Data Fusion: A decision analysis tool that quantifies geological and parametric uncertainty

International Nuclear Information System (INIS)

Porter, D.W.

1995-01-01

Engineering projects such as siting waste facilities and performing remediation are often driven by geological and hydrogeological uncertainties. Geological understanding and hydrogeological parameters such as hydraulic conductivity are needed to achieve reliable engineering design. Information form non-invasive and minimal invasive data sets offers potential for reduction in uncertainty, but a single data type does not usually meet all needs. Data Fusion uses Bayesian statistics to update prior knowledge with information from diverse data sets as the data is acquired. Prior knowledge takes the form of first principles models (e.g., groundwater flow) and spatial continuity models for heterogeneous properties. The variability of heterogeneous properties is modeled in a form motivated by statistical physics as a Markov random field. A computer reconstruction of targets of interest is produced within a quantified statistical uncertainty. The computed uncertainty provides a rational basis for identifying data gaps for assessing data worth to optimize data acquisition. Further, the computed uncertainty provides a way to determine the confidence of achieving adequate safety, margins in engineering design. Beyond design, Data Fusion provides the basis for real time computer monitoring of remediation. Working with the DOE Office of Technology (OTD), the authors have developed and patented a Data Fusion Workstation system that has been used on jobs at the Hanford, Savannah River, Pantex and Fernald DOE sites. Further, applications include an army depot at Letterkenney, PA and commercial industrial sites

Data Fusion: A decision analysis tool that quantifies geological and parametric uncertainty

International Nuclear Information System (INIS)

Porter, D.W.

1996-01-01

Engineering projects such as siting waste facilities and performing remediation are often driven by geological and hydrogeological uncertainties. Geological understanding and hydrogeological parameters such as hydraulic conductivity are needed to achieve reliable engineering design. Information from non-invasive and minimally invasive data sets offers potential for reduction in uncertainty, but a single data type does not usually meet all needs. Data Fusion uses Bayesian statistics to update prior knowledge with information from diverse data sets as the data is acquired. Prior knowledge takes the form of first principles models (e.g., groundwater flow) and spatial continuity models for heterogeneous properties. The variability of heterogeneous properties is modeled in a form motivated by statistical physics as a Markov random field. A computer reconstruction of targets of interest is produced within a quantified statistical uncertainty. The computed uncertainty provides a rational basis for identifying data gaps for assessing data worth to optimize data acquisition. Further, the computed uncertainty provides a way to determine the confidence of achieving adequate safety margins in engineering design. Beyond design, Data Fusion provides the basis for real time computer monitoring of remediation. Working with the DOE Office of Technology (OTD), the author has developed and patented a Data Fusion Workstation system that has been used on jobs at the Hanford, Savannah River, Pantex and Fernald DOE sites. Further applications include an army depot at Letterkenney, PA and commercial industrial sites

Using geologic conditions and multiattribute decision analysis to determine the relative favorability of selected areas for siting a high-level radioactive waste repository

International Nuclear Information System (INIS)

Harrison, W.; Edgar, D.E.; Baker, C.H.

1988-05-01

A method is presented for determining the relative favorability of geologically complex areas for isolating high-level radioactive wastes. In applying the method to the northeastern region of the United States, seismicity and tectonic activity were the screening criteria used to divide the region into three areas of increasing seismotectonic risk. Criteria were then used to subdivide the area of lowest seismotectonic risk into six geologically distinct subareas including characteristics, surface-water and groundwater hydrology, potential human intrusion, site geometry, surface characteristics, and tectonic environment. Decision analysis was then used to identify the subareas most favorable from a geologic standpoint for further investigation, with a view to selecting a site for a repository. Three subareas (parts of northeastern Vermont, northern New Hampshire, and western Maine) were found to be the most favorable, using this method and existing data. However, because this study assessed relative geologic favorability, no conclusions should be drawn concerning the absolute suitability of individual subareas for high-level radioactive waste isolation. 34 refs., 7 figs., 20 tabs

The First USGS Global Geologic Map of Europa

Science.gov (United States)

Leonard, E. J.; Patthoff, D. A.; Senske, D.; Collins, G. C.

2017-12-01

Understanding the global scale geology of Europa is paramount to gaining insight into the potential habitability of this icy world. To this end, work is ongoing to complete a global geological map at the scale of 1:15 million that incorporates data at all resolutions collected by the Voyager and Galileo missions. The results of this work will aid the Europa Clipper mission, now in formulation, by providing a framework for collaborative and synergistic science investigations. To understand global geologic and tectonic relations, a total of 10 geologic units have been defined. These include: Low Albedo Ridge Material (lam)—low albedo material that irregularly surrounds large (>20 km) ridge structures; Ridged plains (pr)—distributed over all latitudes and characterized by subparallel to cross-cutting ridges and troughs visible at high resolution (material (b)—linear to curvilinear zones with a distinct, abrupt albedo change from the surrounding region; Crater material (c), Continuous Crater Ejecta (ce) and Discontinuous Crater Ejecta (dce)—features associated with impact craters including the site of the impact, crater material, and the fall-out debris respectively; Low Albedo Chaos (chl), Mottled Albedo Chaos (chm) and High Albedo Chaos (chh)—disrupted terrain with a relatively uniform low albedo, patchy/variegated albedo, and uniform high albedo appearance respectively; Knobby Chaos (chk) - disrupted terrain with rough and blocky texture occurring in the high latitudes. In addition to the geologic units, our mapping also includes structural features—Ridges, Cycloids, Undifferentiated Linea, Crater Rims, Depression Margins, Dome Margins and Troughs. We also introduce a point feature (at the global scale), Microchaos, to denote small (material. The completed map will constrain the distribution of different Europa terrains and provide a general stratigraphic framework to assess the geologic history of Europa from the regional to the global scale. Here, we

Identification, Attribution, and Quantification of Highly Heterogeneous Methane Sources Using a Mobile Stable Isotope Analyzer

Science.gov (United States)

Crosson, E.; Rella, C.; Cunningham, K.

2012-04-01

Despite methane's importance as a potent greenhouse gas second only to carbon dioxide in the magnitude of its contribution to global warming, natural contributions to the overall methane budget are only poorly understood. A big contributor to this gap in knowledge is the highly spatially and temporally heterogeneous nature of most natural (and for that matter anthropogenic) methane sources. This high degree of heterogeneity, where the methane emission rates can vary over many orders of magnitude on a spatial scale of meters or even centimeters, and over a temporal scale of minutes or even seconds, means that traditional methods of emissions flux estimation, such as flux chambers or eddy-covariance, are difficult or impossible to apply. In this paper we present new measurement methods that are capable of detecting, attributing, and quantifying emissions from highly heterogeneous sources. These methods take full advantage of the new class of methane concentration and stable isotope analyzers that are capable of laboratory-quality analysis from a mobile field platform in real time. In this paper we present field measurements demonstrating the real-time detection of methane 'hot spots,' attribution of the methane to a source process via real-time stable isotope analysis, and quantification of the emissions flux using mobile concentration measurements of the horizontal and vertical atmospheric dispersion, combined with atmospheric transport calculations. Although these techniques are applicable to both anthropogenic and natural methane sources, in this initial work we focus primarily on landfills and fugitive emissions from natural gas distribution, as these sources are better characterized, and because they provide a more reliable and stable source of methane for quantifying the measurement uncertainty inherent in the different methods. Implications of these new technologies and techniques are explored for the quantification of natural methane sources in a variety of

A fully-coupled discontinuous Galerkin spectral element method for two-phase flow in petroleum reservoirs

Science.gov (United States)

Taneja, Ankur; Higdon, Jonathan

2018-01-01

A high-order spectral element discontinuous Galerkin method is presented for simulating immiscible two-phase flow in petroleum reservoirs. The governing equations involve a coupled system of strongly nonlinear partial differential equations for the pressure and fluid saturation in the reservoir. A fully implicit method is used with a high-order accurate time integration using an implicit Rosenbrock method. Numerical tests give the first demonstration of high order hp spatial convergence results for multiphase flow in petroleum reservoirs with industry standard relative permeability models. High order convergence is shown formally for spectral elements with up to 8th order polynomials for both homogeneous and heterogeneous permeability fields. Numerical results are presented for multiphase fluid flow in heterogeneous reservoirs with complex geometric or geologic features using up to 11th order polynomials. Robust, stable simulations are presented for heterogeneous geologic features, including globally heterogeneous permeability fields, anisotropic permeability tensors, broad regions of low-permeability, high-permeability channels, thin shale barriers and thin high-permeability fractures. A major result of this paper is the demonstration that the resolution of the high order spectral element method may be exploited to achieve accurate results utilizing a simple cartesian mesh for non-conforming geological features. Eliminating the need to mesh to the boundaries of geological features greatly simplifies the workflow for petroleum engineers testing multiple scenarios in the face of uncertainty in the subsurface geology.

Simulation of geothermal water extraction in heterogeneous reservoirs using dynamic unstructured mesh optimisation

Science.gov (United States)

Salinas, P.; Pavlidis, D.; Jacquemyn, C.; Lei, Q.; Xie, Z.; Pain, C.; Jackson, M.

2017-12-01

It is well known that the pressure gradient into a production well increases with decreasing distance to the well. To properly capture the local pressure drawdown into the well a high grid or mesh resolution is required; moreover, the location of the well must be captured accurately. In conventional simulation models, the user must interact with the model to modify grid resolution around wells of interest, and the well location is approximated on a grid defined early in the modelling process.We report a new approach for improved simulation of near wellbore flow in reservoir scale models through the use of dynamic mesh optimisation and the recently presented double control volume finite element method. Time is discretized using an adaptive, implicit approach. Heterogeneous geologic features are represented as volumes bounded by surfaces. Within these volumes, termed geologic domains, the material properties are constant. Up-, cross- or down-scaling of material properties during dynamic mesh optimization is not required, as the properties are uniform within each geologic domain. A given model typically contains numerous such geologic domains. Wells are implicitly coupled with the domain, and the fluid flows is modelled inside the wells. The method is novel for two reasons. First, a fully unstructured tetrahedral mesh is used to discretize space, and the spatial location of the well is specified via a line vector, ensuring its location even if the mesh is modified during the simulation. The well location is therefore accurately captured, the approach allows complex well trajectories and wells with many laterals to be modelled. Second, computational efficiency is increased by use of dynamic mesh optimization, in which an unstructured mesh adapts in space and time to key solution fields (preserving the geometry of the geologic domains), such as pressure, velocity or temperature, this also increases the quality of the solutions by placing higher resolution where required

Scaling impacts on environmental controls and spatial heterogeneity of soil organic carbon stocks

Science.gov (United States)

Mishra, U.; Riley, W. J.

2015-07-01

The spatial heterogeneity of land surfaces affects energy, moisture, and greenhouse gas exchanges with the atmosphere. However, representing the heterogeneity of terrestrial hydrological and biogeochemical processes in Earth system models (ESMs) remains a critical scientific challenge. We report the impact of spatial scaling on environmental controls, spatial structure, and statistical properties of soil organic carbon (SOC) stocks across the US state of Alaska. We used soil profile observations and environmental factors such as topography, climate, land cover types, and surficial geology to predict the SOC stocks at a 50 m spatial scale. These spatially heterogeneous estimates provide a data set with reasonable fidelity to the observations at a sufficiently high resolution to examine the environmental controls on the spatial structure of SOC stocks. We upscaled both the predicted SOC stocks and environmental variables from finer to coarser spatial scales (s = 100, 200, and 500 m and 1, 2, 5, and 10 km) and generated various statistical properties of SOC stock estimates. We found different environmental factors to be statistically significant predictors at different spatial scales. Only elevation, temperature, potential evapotranspiration, and scrub land cover types were significant predictors at all scales. The strengths of control (the median value of geographically weighted regression coefficients) of these four environmental variables on SOC stocks decreased with increasing scale and were accurately represented using mathematical functions (R2 = 0.83-0.97). The spatial structure of SOC stocks across Alaska changed with spatial scale. Although the variance (sill) and unstructured variability (nugget) of the calculated variograms of SOC stocks decreased exponentially with scale, the correlation length (range) remained relatively constant across scale. The variance of predicted SOC stocks decreased with spatial scale over the range of 50 m to ~ 500 m, and remained

An open, object-based modeling approach for simulating subsurface heterogeneity

Science.gov (United States)

Bennett, J.; Ross, M.; Haslauer, C. P.; Cirpka, O. A.

2017-12-01

Characterization of subsurface heterogeneity with respect to hydraulic and geochemical properties is critical in hydrogeology as their spatial distribution controls groundwater flow and solute transport. Many approaches of characterizing subsurface heterogeneity do not account for well-established geological concepts about the deposition of the aquifer materials; those that do (i.e. process-based methods) often require forcing parameters that are difficult to derive from site observations. We have developed a new method for simulating subsurface heterogeneity that honors concepts of sequence stratigraphy, resolves fine-scale heterogeneity and anisotropy of distributed parameters, and resembles observed sedimentary deposits. The method implements a multi-scale hierarchical facies modeling framework based on architectural element analysis, with larger features composed of smaller sub-units. The Hydrogeological Virtual Reality simulator (HYVR) simulates distributed parameter models using an object-based approach. Input parameters are derived from observations of stratigraphic morphology in sequence type-sections. Simulation outputs can be used for generic simulations of groundwater flow and solute transport, and for the generation of three-dimensional training images needed in applications of multiple-point geostatistics. The HYVR algorithm is flexible and easy to customize. The algorithm was written in the open-source programming language Python, and is intended to form a code base for hydrogeological researchers, as well as a platform that can be further developed to suit investigators' individual needs. This presentation will encompass the conceptual background and computational methods of the HYVR algorithm, the derivation of input parameters from site characterization, and the results of groundwater flow and solute transport simulations in different depositional settings.

The application of quadtree algorithm for information integration in the high-level radioactive waste geological disposal

International Nuclear Information System (INIS)

Gao Min; Zhong Xia; Huang Shutao

2008-01-01

A multi-source database for high-level radioactive waste geological disposal, aims to promote the information process of the geological of HLW. In the periods of the multi-dimensional and multi-source and the integration of information and applications, it also relates to computer software and hardware, the paper preliminary analysises the data resources Beishan area, Gansu Province. The paper introduces a theory based on GIS technology and methods and open source code GDAL application, at the same time, it discusses the technical methods how to finish the application of the Quadtree algorithm in the area of information resources management system, fully sharing, rapid retrieval and so on. A more detailed description of the characteristics of existing data resources, space-related data retrieval algorithm theory, programming design and implementation of ideas are showed in the paper. (authors)

Southeastern Regional Geologic Characterization Report. Executive summary. Final report

International Nuclear Information System (INIS)

1985-08-01

This Executive Summary of the final Southeastern Regional Geologic Characterization Report (RGCR) is issued primarily for public information purposes, and provides a general overview of the report. The complete RGCR presents available regional geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in central Maryland; noncoastal Virginia, North Carolina, and South Carolina; and northern Georgia. For each of the states within the Southeastern Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening

Assessment of uncertainties associated with characterization of geological environment in the Tono area. Japanese fiscal year, 2006 (Contract research)

International Nuclear Information System (INIS)

Toida, Masaru; Suyama, Yasuhiro; Seno, Shoji; Atsumi, Hiroyuki; Ogata, Nobuhisa

2008-03-01

'Geoscientific research' performed at the Tono Geoscience Center is developing site investigation, characterization and assessment techniques for understanding of geological environment. Their important themes are to establish a methodology for analyzing uncertainties in heterogeneous geological environment, and to develop investigation techniques for reducing the uncertainties efficiently. This study proposes a new approach where all the possible options in the models and data-sets that cannot be excluded in the light of the evidence available, are identified. This approach enables uncertainties associated with the understanding at a given stage of the site characterization to be made explicitly using an uncertainty analysis technique based on Fuzzy geostatistics. This, in turn, supports the design of the following investigation stage to reduce the uncertainties efficiently. In the study, current knowledge had been compiled, and the technique had been advanced through geological modeling and groundwater analyses in the Tono area. This report systematized the uncertainty analysis methodology associated with the characterization of the geological environment, and organized the procedure of the methodology with the application examples in the study. This report also dealt with investigation techniques for reducing the uncertainties efficiently, and underground facility design options for handling geological uncertainties based on the characterization of the geological environment. (author)

Probabilistic modelling of the damage of geological barriers of the nuclear waste deep storage - ENDOSTON project, final report

International Nuclear Information System (INIS)

2010-01-01

As the corrosion of metallic casings of radioactive waste storage packages releases hydrogen under pressure, and as the overpressure disturbs the stress fields, the authors report the development of methodologies and numerical simulation tools aimed at a better understanding of the mechanisms of development and propagation of crack networks in the geological barrier due to this overpressure. They present a probabilistic model of the formation of crack networks in rocks, with the probabilistic post-processing of a finite element calculation. They describe the modelling of crack propagation and damage in quasi-brittle materials. They present the ENDO-HETEROGENE model for the formation and propagation of cracks in heterogeneous media, describe the integration of the model into the Aster code, and report the model validation (calculation of the stress intensity factor, grid dependence). They finally report a test case of the ENDO-HETEROGENE model

The Simple, Effective Synthesis of Highly Dispersed Pd/C and CoPd/C Heterogeneous Catalysts via Charge-Enhanced Dry Impregnation

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Lawrence D’Souza

2016-05-01

Full Text Available Pd/C and CoPd/C heterogeneous catalysts have been synthesized by adopting Charge Enhanced Dry Impregnation (CEDI. The particles size distribution, their high metal surface-to-bulk ratios, and synthesis feasibility are unmatchable to any known noble metal bimetallic heterogeneous catalyst preparation techniques. Next generation Fuel Cells and Fischer-Tropsch catalytic processes economy will be benefited from the proposed methodology.

Risk-Based Management of Contaminated Groundwater: The Role of Geologic Heterogeneity, Exposure and Cancer Risk in Determining the Performance of Aquifer Remediation

International Nuclear Information System (INIS)

Maxwell, R.M.; Carle, S.F.; Tompson, A.F.B.

2000-01-01

The effectiveness of aquifer remediation is typically expressed in terms of a reduction in contaminant concentrations relative to a regulated maximum contaminant level (MCL), and is usually confined by sparse monitoring data and/or simple model calculations. Here, the effectiveness of remediation is examined from a risk-based perspective that goes beyond the traditional MCL concept. A methodology is employed to evaluate the health risk to individuals exposed to contaminated household water that is produced from groundwater. This approach explicitly accounts for differences in risk arising from variability in individual physiology and water use, the uncertainty in estimating chemical carcinogenesis for different individuals, and the uncertainties and variability in contaminant concentrations within groundwater. A hypothetical contamination scenario is developed as a case study in a saturated, alluvial aquifer underlying a real Superfund site. A baseline (unremediated) human exposure and health risk scenario, as induced by contaminated groundwater pumped from this site, is predicted and compared with a similar estimate based upon pump-and-treat exposure intervention. The predicted reduction in risk in the remediation scenario is not an equitable one-that is, it is not uniform to all individuals within a population and varies according to the level of uncertainty in prediction. The importance of understanding the detailed hydrogeologic connections that are established in the heterogeneous geologic regime between the contaminated source, municipal receptors, and remediation wells, and its relationship to this uncertainty is demonstrated. Using two alternative pumping rates, we develop cost-benefit curves based upon reduced exposure and risk to different individuals within the population, under the presence of uncertainty

Field verification of advanced transport models of radionuclides in heterogeneous soils

International Nuclear Information System (INIS)

Visser, W.; Meurs, G.A.M.; Weststrate, F.A.

1991-01-01

This report deals with a verification study of advanced transport models of radionuclides in heterogeneous soils. The study reported here is the third phase of a research program carried out by Delft Geotechnics concerning the influence of soil heterogeneities on the migration of radionuclides in the soil and soil-water system. Phases 1 and 2 have been reported earlier in the EC Nuclear Science and technology series (EUR 12111 EN, 1989). The verification study involves the predictive modelling of a field tracer experiment carried out by the British Geological Survey (BGS) at Drigg, Cumbria (UK). Conservative (I 131 , Cl-, H 3 ) as well as non-conservative (Co-EDTA) tracers were used. The inverse modelling shows that micro dispersion may be considered as a soil constant related to grainsize. Micro dispersion shows a slow increase with distance from the source. This increase is caused by mass transfer between adjacent layers of different permeability. Macro dispersion is observed when sampling over a larger interval then permitted by the detail with which the heterogeneity is described in the model. The prediction of the migration of radionuclides through heterogeneous soils is possible. The advection dispersion equation seems to be an adequate description of the migration of conservative tracers. The models based on this equation give comparable results on a small field test scale (3.5 m). The prediction of the migration of adsorbing species is more difficult. The mathematical descriptions seem appropriate, but the heterogeneity in soils seems to create a higher order of uncertainty which can not be described as yet with calculation strategies available at this moment

The Treatment of Geological Time & the History of Life on Earth in High School Biology Textbooks

Science.gov (United States)

Summers, Gerald; Decker, Todd; Barrow, Lloyd

2007-01-01

In spite of the importance of geological time in evolutionary biology, misconceptions about historical events in the history of life on Earth are common. Glenn (1990) has documented a decline from 1960 to 1989 in the amount of space devoted to the history of life in high school earth science textbooks, but we are aware of no similar study in…

Intensive evaporation and boiling of a heterogeneous liquid droplet with an explosive disintegration in high-temperature gas area

Directory of Open Access Journals (Sweden)

Piskunov Maxim V.

2016-01-01

Full Text Available The using of the high-speed (not less than 105 frames per second video recording tools (“Phantom” and the software package ("TEMA Automotive" allowed carrying out an experimental research of laws of intensive vaporization with an explosive disintegration of heterogeneous (with a single solid nontransparent inclusion liquid droplet (by the example of water in high-temperature (500-800 K gases (combustion products. Times of the processes under consideration and stages (liquid heat-up, evaporation from an external surface, bubble boiling at internal interfaces, growth of bubble sizes, explosive droplet breakup were established. Necessary conditions of an explosive vaporization of a heterogeneous droplet were found out. Mechanisms of this process and an influence of properties of liquid and inclusion material on them were determined.

Geology and bedrock engineering

International Nuclear Information System (INIS)

1985-11-01

This book deals with geology of Korea which includes summary, geology in central part and southern part in Korea and characteristic of geology structure, limestone like geology property of limestone, engineered property of limestone, and design and construction case in limestone area. It also introduces engineered property of the cenozoic, clay rock and shale, geologic and engineered property of phyllite and stratum.

China organic-rich shale geologic features and special shale gas production issues

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Yiwen Ju

2014-06-01

Full Text Available The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, and lithology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM proposes a new topic: whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary production issues of shale gas in China were discussed with suggestions.

The U.S. Geological Survey Geologic Collections Management System (GCMS)—A master catalog and collections management plan for U.S. Geological Survey geologic samples and sample collections

Science.gov (United States)

,

2015-01-01

The U.S. Geological Survey (USGS) is widely recognized in the earth science community as possessing extensive collections of earth materials collected by research personnel over the course of its history. In 2006, a Geologic Collections Inventory was conducted within the USGS Geology Discipline to determine the extent and nature of its sample collections, and in 2008, a working group was convened by the USGS National Geologic and Geophysical Data Preservation Program to examine ways in which these collections could be coordinated, cataloged, and made available to researchers both inside and outside the USGS. The charge to this working group was to evaluate the proposition of creating a Geologic Collections Management System (GCMS), a centralized database that would (1) identify all existing USGS geologic collections, regardless of size, (2) create a virtual link among the collections, and (3) provide a way for scientists and other researchers to obtain access to the samples and data in which they are interested. Additionally, the group was instructed to develop criteria for evaluating current collections and to establish an operating plan and set of standard practices for handling, identifying, and managing future sample collections. Policies and procedures promoted by the GCMS would be based on extant best practices established by the National Science Foundation and the Smithsonian Institution. The resulting report—USGS Circular 1410, “The U.S. Geological Survey Geologic Collections Management System (GCMS): A Master Catalog and Collections Management Plan for U.S. Geological Survey Geologic Samples and Sample Collections”—has been developed for sample repositories to be a guide to establishing common practices in the collection, retention, and disposal of geologic research materials throughout the USGS.

Analysis of the Coupled Influence of Hydraulic Conductivity and Porosity Heterogeneity on Probabilistic Risk Analysis

Science.gov (United States)

Libera, A.; Henri, C.; de Barros, F.

2017-12-01

Heterogeneities in natural porous formations, mainly manifested through the hydraulic conductivity (K) and, to a lesser degree, the porosity (Φ), largely control subsurface flow and solute transport. The influence of the heterogeneous structure of K on flow and solute transport processes has been widely studied, whereas less attention is dedicated to the joint heterogeneity of conductivity and porosity fields. Our study employs computational tools to investigate the joint effect of the spatial variabilities of K and Φ on the transport behavior of a solute plume. We explore multiple scenarios, characterized by different levels of heterogeneity of the geological system, and compare the computational results from the joint K and Φ heterogeneous system with the results originating from the generally adopted constant porosity case. In our work, we assume that the heterogeneous porosity is positively correlated to hydraulic conductivity. We perform numerical Monte Carlo simulations of conservative and reactive contaminant transport in a 3D aquifer. Contaminant mass and plume arrival times at multiple control planes and/or pumping wells operating under different extraction rates are analyzed. We employ different probabilistic metrics to quantify the risk at the monitoring locations, e.g., increased lifetime cancer risk and exceedance of Maximum Contaminant Levels (MCLs), under multiple transport scenarios (i.e., different levels of heterogeneity, conservative or reactive solutes and different contaminant species). Results show that early and late arrival times of the solute mass at the selected sensitive locations (i.e. control planes/pumping wells) as well as risk metrics are strongly influenced by the spatial variability of the Φ field.

New non-linear model of groundwater recharge: Inclusion of memory, heterogeneity and visco-elasticity

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Spannenberg Jescica

2017-09-01

Full Text Available Fractional differentiation has adequate use for investigating real world scenarios related to geological formations associated with elasticity, heterogeneity, viscoelasticity, and the memory effect. Since groundwater systems exist in these geological formations, modelling groundwater recharge as a real world scenario is a challenging task to do because existing recharge estimation methods are governed by linear equations which make use of constant field parameters. This is inadequate because in reality these parameters are a function of both space and time. This study therefore concentrates on modifying the recharge equation governing the EARTH model, by application of the Eton approach. Accordingly, this paper presents a modified equation which is non-linear, and accounts for parameters in a way that it is a function of both space and time. To be more specific, herein, recharge and drainage resistance which are parameters within the equation, became a function of both space and time. Additionally, the study entailed solving the non-linear equation using an iterative method as well as numerical solutions by means of the Crank-Nicolson scheme. The numerical solutions were used alongside the Riemann-Liouville, Caputo-Fabrizio, and Atangana-Baleanu derivatives, so that account was taken for elasticity, heterogeneity, viscoelasticity, and the memory effect. In essence, this paper presents a more adequate model for recharge estimation.

U.S. Geological Survey flies high for now

Science.gov (United States)

Clinton is asking Congress to keep the U.S. Geological Survey (USGS) alive and well in FY 1996. With a proposed 2.6% increase to $586 million, the Clinton request flies in the face of the Republican Contract with America that calls for abolishing the survey.Indeed, Clinton has made it clear that the onus will be on Congress if it wants to make major cuts at USGS. As Secretary of the Interior Bruce Babbitt puts it: “Good science is essential to good management.”

Heterogeneous Gpu&Cpu Cluster For High Performance Computing In Cryptography

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Michał Marks

2012-01-01

Full Text Available This paper addresses issues associated with distributed computing systems andthe application of mixed GPU&CPU technology to data encryption and decryptionalgorithms. We describe a heterogenous cluster HGCC formed by twotypes of nodes: Intel processor with NVIDIA graphics processing unit and AMDprocessor with AMD graphics processing unit (formerly ATI, and a novel softwareframework that hides the heterogeneity of our cluster and provides toolsfor solving complex scientific and engineering problems. Finally, we present theresults of numerical experiments. The considered case study is concerned withparallel implementations of selected cryptanalysis algorithms. The main goal ofthe paper is to show the wide applicability of the GPU&CPU technology tolarge scale computation and data processing.

Key radionuclides and parameters that determine performance of geologic repositories for high-level radioactive wastes

International Nuclear Information System (INIS)

Joonhong Ahn; Atsuyuki Suzuki

1993-01-01

This paper presents results of a mathematical analysis for performance of the engineered barriers of high-level radioactive waste repositories. The main body of the mathematical model developed in this study is mass transport of actinides in a bentonite region. In an analysis of actinide transport, radioactive decay chain and effects of low solubilities must be taken into account. In many previous models for mass transport in engineered barriers including radioactive decay chain, however, boundary conditions at the interface between the waste form and the bentonite region cannot be determined flexibly. In some models, solubility-limited boundary condition is assumed for all the members in a chain. In order to investigate what are key radionuclides and parameters that control performance of engineered barriers of a geologic repository, we must evaluate mass transport with the source boundary condition determined by a detailed analysis on mass transfer at the boundary. In this study, we developed a mathematical model, which can determine whether the inner boundary condition is solubility-limited or congruent release, based on a mathematical analysis for mass transfer at the glass dissolution location, and how long the solubility-limited boundary condition applies. Based on the mathematical model, we point out radionuclides and parameters that have primary influences on the performance of a repository, and investigate a reasonable strategy for coupling geologic disposal and partitioning of those key radionuclides from the standpoint of reducing hazard of geologic disposal. (authors). 4 tabs., 2 figs., 8 refs

Geostatistical Simulation of Hydrofacies Heterogeneity of the West Thessaly Aquifer Systems in Greece

International Nuclear Information System (INIS)

Modis, K.; Sideri, D.

2013-01-01

Integrating geological properties, such as relative positions and proportions of different hydrofacies, is of highest importance in order to render realistic geological patterns. Sequential indicator simulation (SIS) and Plurigaussian simulation (PS) are alternative methods for conceptual and deterministic modeling for the characterization of hydrofacies distribution. In this work, we studied the spatial differentiation of hydrofacies in the alluvial aquifer system of West Thessaly basin in Greece. For this, we applied both SIS and PS techniques to an extensive set of borehole data from that basin. Histograms of model versus experimental hydrofacies proportions and indicative cross sections were plotted in order to validate the results. The PS technique was shown to be more effective in reproducing the spatial characteristics of the different hydrofacies and their distribution across the study area. In addition, the permeability differentiations reflected in the PS model are in accordance to known heterogeneities of the aquifer capacity.

Geostatistical Simulation of Hydrofacies Heterogeneity of the West Thessaly Aquifer Systems in Greece

Energy Technology Data Exchange (ETDEWEB)

Modis, K., E-mail: kmodis@mail.ntua.gr; Sideri, D. [National Technical University of Athens, School of Mining and Metallurgical Engineering (Greece)

2013-06-15

Integrating geological properties, such as relative positions and proportions of different hydrofacies, is of highest importance in order to render realistic geological patterns. Sequential indicator simulation (SIS) and Plurigaussian simulation (PS) are alternative methods for conceptual and deterministic modeling for the characterization of hydrofacies distribution. In this work, we studied the spatial differentiation of hydrofacies in the alluvial aquifer system of West Thessaly basin in Greece. For this, we applied both SIS and PS techniques to an extensive set of borehole data from that basin. Histograms of model versus experimental hydrofacies proportions and indicative cross sections were plotted in order to validate the results. The PS technique was shown to be more effective in reproducing the spatial characteristics of the different hydrofacies and their distribution across the study area. In addition, the permeability differentiations reflected in the PS model are in accordance to known heterogeneities of the aquifer capacity.

Application of Ga-Al discrimination plots in identification of high strength granitic host rocks for deep geological repository of high level radioactive waste

International Nuclear Information System (INIS)

Bajpai, R.K.; Narayan, P.K.; Trivedi, R.K.; Purohit, M.K.

2010-01-01

The permanent disposal of vitrified high level wastes and in some cases even spent fuel, is being planned in specifically designed and built deep geological repository located in the depth range of 500-600m in appropriate host rock at carefully selected sites. Such facilities are expected to provide very long term isolation and confinement to the disposed waste by means of long term mechanical stability of such structures that results from very high strength and homogeneity of the chosen rock, geochemical compatible environment around the disposed waste and general lack of groundwater. In Indian geological repository development programme, granites have been selected as target host rock and large scale characterization studies have been undertaken to develop database of mineralogy, petrology, geochemistry and rock mechanical characteristics. The paper proposes a new approach for demarcation of high strength homogeneous granite rocks from within an area of about 100 square kilometres wherein a cocktail of granites of different origins with varying rock mass characteristics co exists. The study area is characterised by the presence of A, S and I type granites toughly intermixed. The S type granites are derived from sedimentary parent material and therefore carry relics of parent fabric and at times undigested material with resultant reduction in their strength and increased inhomogeneity. On the other hand I type varieties are derived from igneous parents and are more homogeneous with sufficient strength. The A type granites are emplaced as molten mass in a complete non-tectonic setting with resultant homogeneous compositions, absence of tectonic fabric and very high strength. Besides they are silica rich with less vulnerability to alterations with time. Thus A type granites are most suited for construction of Deep Geological Repository. For developing a geochemical approach for establishing relation between chemical compositions and rock strength parameters, a

Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. Part 2. Engineering technology for geological disposal

International Nuclear Information System (INIS)

1999-11-01

Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the deep geological disposal concept for high-level radioactive wastes (HLW) in Japan. The present document, part 2 of the progress report, concerns engineering aspect with reference to Japanese geological disposal plan, according to which the vitrified HLW will be disposed of into a deep, stable rock mass with thick containers and surrounding buffer materials at the depth of several hundred meters. It discusses on multi-barrier systems consisting of a series of engineered and natural barriers that will isolate radioactive nuclides effectively and retard their migrations to the biosphere environment. Performance of repository components, including specifications of containers for vitrified HLW and their overpacks under design as well as buffer material such as Japanese bentonite to be placed in between are described referring also to such possible problems as corrosion arising from the supposed system. It also presents plans and designs for underground disposal facilities, and the presumed management of the underground facilities. (Ohno, S.)

Proposals of geological sites for L/ILW and HLW repositories. Geological background. Text volume

International Nuclear Information System (INIS)

2008-01-01

On April 2008, the Swiss Federal Council approved the conceptual part of the Sectoral Plan for Deep Geological Repositories. The Plan sets out the details of the site selection procedure for geological repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). It specifies that selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages, the first one (the subject of this report) being the definition of geological siting regions within which the repository projects will be elaborated in more detail in the later stages of the Sectoral Plan. The geoscientific background is based on the one hand on an evaluation of the geological investigations previously carried out by Nagra on deep geological disposal of HLW and L/ILW in Switzerland (investigation programmes in the crystalline basement and Opalinus Clay in Northern Switzerland, investigations of L/ILW sites in the Alps, research in rock laboratories in crystalline rock and clay); on the other hand, new geoscientific studies have also been carried out in connection with the site selection process. Formulation of the siting proposals is conducted in five steps: A) In a first step, the waste inventory is allocated to the L/ILW and HLW repositories; B) The second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability, reliability of geological findings and engineering suitability; C) In the third step, the large-scale geological-tectonic situation is assessed and large-scale areas that remain under consideration are defined. For the L

Heterogeneous inflation expectations, learning, and market outcomes

OpenAIRE

Madeira, Carlos; Zafar, Basit

2012-01-01

Using the panel component of the Michigan Survey of Consumers, we show that individuals, in particular women and ethnic minorities, are highly heterogeneous in their expectations of inflation. We estimate a model of inflation expectations based on learning from experience that also allows for heterogeneity in both private information and updating. Our model vastly outperforms existing models of inflation expectations in explaining the heterogeneity in the data. We find that women, ethnic mino...

High Precision Positioning at Field Camp: Using GNSS as the primary data source to answer geologic questions

Science.gov (United States)

Crosby, B. T.; Lauer, I. H.; Pratt-Sitaula, B.

2017-12-01

Thanks to the availability and accessibility of GPS/GNSS enabled consumer grade positioning devices, GNSS are nearly ubiquitous in both geologic field research and education. Though the devices offer sufficient precision to geotag images, digital field book entries or measurements, positions themselves are not precise enough to accomplish independent geodetic analysis. As a consequence, most students learn about GNSS at a tool that aids other forms of geologic data acquisition rather serving as the primary source itself. To resolve this, we developed and tested a three-unit teaching module within the GETSI - SERC curriculum framework that reinforces high precision positioning as a primary source of geologic data. Units focus on three core topics: GNSS Fundamentals, Kinematic GNSS and Static GNSS Methods. Module goals enable students to (a) design and conduct a GNSS survey to answer a geologic question, (b) justify why their GNSS technique is appropriate to their question and (c) to articulate how answering their question benefits society. Skill building is via quantitative and qualitative analysis, concept sketches, and both field and office based data acquisition and interrogation. Exercises are site-independent and include example datasets for those unable to travel. In the summer of 2017, we tested the module with 20 undergraduate students over two days at the ISU field geology course. Located in the Lost River Range of Idaho, positioned among active normal faults, we not only explored the use of static GNSS data for active tectonics but visited a station in person. For a summative assessment, we focused on kinematic GNSS, using RTK rovers to reoccupy leveling monuments spanning the active Lost River fault that ruptured in 1983 (M 7.0). The data collected by our class quantified aseismic deformation occurring in the 30+ years since that event. Displacements were significantly larger than the instrumental uncertainty, confirming that RTK was an appropriate tool

Study on geology and geological structure based on literature studies

International Nuclear Information System (INIS)

Funaki, Hironori; Ishii, Eiichi; Yasue, Ken-ichi; Takahashi, Kazuharu

2005-03-01

Japan Nuclear Cycle Development Institute (JNC) is proceeding with underground research laboratory (URL) project for the sedimentary rock in Horonobe, Hokkaido. This project is an investigation project which is planned over 20 years. Surface-based investigations (Phase 1) have been conducted for the present. The purposes of the Phase 1 are to construct the geological environment model (geological-structural, hydrogeological, and hydrochemical models) and to confirm the applicability of investigation technologies for the geological environment. The geological-structural model comprises the base for the hydrogeological and hydrochemical models. We constructed the geological-structural model by mainly using data obtained from literature studies. Particulars regarding which data the model is based on and who has performed the interpretation are also saved for traceability. As a result, we explain the understanding of degree and the need of information on stratigraphy and discontinuous structure. (author)

Hydrogeological Properties of Geological Elements in Geological Model around KURT

Energy Technology Data Exchange (ETDEWEB)

Park, Kyung Woo; Kim, Kyung Soo; Koh, Yong Kwon; Choi, Jong Won [Korea Atomic Energy Institue, Daejeon (Korea, Republic of)

2012-09-15

To develop site characterization technologies for a radioactive waste disposal research in KAERI, the geological and hydrogeological investigations have been carried out since 1997. In 2006, the KURT (KAERI Underground Research Tunnel) was constructed to study a solute migration, a microbiology and an engineered barrier system as well as deeply to understand geological environments in in-situ condition. This study is performed as one of the site characterization works around KURT. Several investigations such as a lineament analysis, a borehole/tunnel survey, a geophyscial survey and logging in borehole, were used to construct the geological model. As a result, the geological model is constructed, which includes the lithological model and geo-structural model in this study. Moreover, from the results of the in-situ hydraulic tests, the hydrogeological properties of elements in geological model were evaluated.

Hydrogeological Properties of Geological Elements in Geological Model around KURT

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Soo; Koh, Yong Kwon; Choi, Jong Won

2012-01-01

To develop site characterization technologies for a radioactive waste disposal research in KAERI, the geological and hydrogeological investigations have been carried out since 1997. In 2006, the KURT (KAERI Underground Research Tunnel) was constructed to study a solute migration, a microbiology and an engineered barrier system as well as deeply to understand geological environments in in-situ condition. This study is performed as one of the site characterization works around KURT. Several investigations such as a lineament analysis, a borehole/tunnel survey, a geophyscial survey and logging in borehole, were used to construct the geological model. As a result, the geological model is constructed, which includes the lithological model and geo-structural model in this study. Moreover, from the results of the in-situ hydraulic tests, the hydrogeological properties of elements in geological model were evaluated.

How many geologic repositories will be needed

International Nuclear Information System (INIS)

Evans, T.J.; Halstead, R.J.

1987-01-01

DOE's postponement of site-specific work on the second repository program had rekindled debate over the number of geologic repositories needed for disposal of high level radioactive waste. The multiple repository approach grew out of the March, 1979 IRG report, which recommended co-disposal of civilian and defense HLW in a system of regional repositories. The multiple repository approach was adopted by DOE, and incorporated in the Nuclear Waste Policy Act passed by Congress in December, 1982. Since the late 1970's, the slower than anticipated growth of the nuclear power industry has substantially reduced earlier estimates of the amount of civilian spent fuel which will require geologic disposal. Reactors currently in operation (78.5 GWe) and reactors in the construction pipeline (28 GWe) are expected to discharge about 103,200 MTU of spent fuel by the year 2036, assuming no increase in fuel burnup rate. By the year 2020, defense high level radioactive wastes equivalent to as much as 27,000 MTU could require geologic disposal. Small amounts of high level waste from other sources will also require geologic disposal. Total disposal requirements appear to be less than 140,000 MTU. The five sites nominated for the first repository, as well as hypothetical sites in granite, the host rock under primary consideration for the second repository, all appear capable of accommodating up to 140,000 MTU

The Biot coefficient for a low permeability heterogeneous limestone

Science.gov (United States)

Selvadurai, A. P. S.

2018-04-01

This paper presents the experimental and theoretical developments used to estimate the Biot coefficient for the heterogeneous Cobourg Limestone, which is characterized by its very low permeability. The coefficient forms an important component of the Biot poroelastic model that is used to examine coupled hydro-mechanical and thermo-hydro-mechanical processes in the fluid-saturated Cobourg Limestone. The constraints imposed by both the heterogeneous fabric and its extremely low intact permeability [K \\in (10^{-23},10^{-20}) m2 ] require the development of alternative approaches to estimate the Biot coefficient. Large specimen bench-scale triaxial tests (150 mm diameter and 300 mm long) that account for the scale of the heterogeneous fabric are complemented by results for the volume fraction-based mineralogical composition derived from XRD measurements. The compressibility of the solid phase is based on theoretical developments proposed in the mechanics of multi-phasic elastic materials. An appeal to the theory of multi-phasic elastic solids is the only feasible approach for examining the compressibility of the solid phase. The presence of a number of mineral species necessitates the use of the theories of Voigt, Reuss and Hill along with the theories proposed by Hashin and Shtrikman for developing bounds for the compressibility of the multi-phasic geologic material composing the skeletal fabric. The analytical estimates for the Biot coefficient for the Cobourg Limestone are compared with results for similar low permeability rocks reported in the literature.

Radon soil gas measurements in a geological versatile region as basis to improve the prediction of areas with a high radon potential

International Nuclear Information System (INIS)

Kabrt, Franz; Rechberger, Fabian; Schuff, Michael; Seidel, Claudia; Baumgartner, Andreas; Friedmann, Harry; Maringer, Franz Josef

2014-01-01

With the aim to predict the radon potential by geological data, radon soil gas measurements were made in a selected region in Styria, Austria. This region is characterised by mean indoor radon potentials of 130-280 Bq m -3 and a high geological diversity. The distribution of the individual measuring sites was selected on the basis of geological aspects and the distribution of area settlements. In this work, the radon soil gas activity concentration and the soil permeability were measured at 100 sites, each with three single measurements. Furthermore, the local dose rate was determined and soil samples were taken at each site to determine the activity concentration of natural radionuclides. During two investigation periods, long-term soil gas radon measurements were made to study the time dependency of the radon activity concentration. All the results will be compared and investigated for correlation among each other to improve the prediction of areas with high radon potential. (authors)

Evaluation of geologic and geophysical techniques for surface-to-subsurface projections of geologic characteristics in crystalline rock

International Nuclear Information System (INIS)

1985-07-01

Granitic and gneissic rock complexes are being considered for their potential to contain and permanently isolate high-level nuclear waste in a deep geologic repository. The use of surface geologic and geophysical techniques has several advantages over drilling and testing methods for geologic site characterization in that the techniques are typically less costly, provide data over a wider area, and do not jeopardize the physical integrity of a potential repository. For this reason, an extensive literature review was conducted to identify appropriate surface geologic and geophysical techniques that can be used to characterize geologic conditions in crystalline rock at proposed repository depths of 460 to 1,220 m. Characterization parameters such as rock quality; fracture orientation, spacing; and aperture; depths to anomalies; degree of saturation; rock body dimensions; and petrology are considered to be of primary importance. Techniques reviewed include remote sensing, geologic mapping, petrographic analysis, structural analysis, gravity and magnetic methods, electrical methods, and seismic methods. Each technique was reviewed with regard to its theoretical basis and field application; geologic parameters that can be evaluated; advantages and limitations, and, where available, case history applications in crystalline rock. Available information indicates that individual techniques provide reliable information on characteristics at the surface, but have limited success in projections to depths greater that approximately 100 m. A combination of integrated techniques combines with data from a limited number of boreholes would significantly improve the reliability and confidence of early characterization studies to provide qualitative rock body characteristics for region-to-area and area-to-site selection evaluations. 458 refs., 32 figs., 14 tabs

High resolution SPECT imaging for visualization of intratumoral heterogeneity using a SPECT/CT scanner dedicated for small animal imaging

International Nuclear Information System (INIS)

Umeda, Izumi O.; Tani, Kotaro; Tsuda, Keisuke

2012-01-01

Tumor interiors are never homogeneous and in vivo visualization of intratumoral heterogeneity would be an innovation that contributes to improved cancer therapy. But, conventional nuclear medicine tests have failed to visualize heterogeneity in vivo because of limited spatial resolution. Recently developed single photon emission computed tomographic (SPECT) scanners dedicated for small animal imaging are of interest due to their excellent spatial resolution of 111 In and simulations of actual small animal imaging. The optimal conditions obtained were validated by in vivo imaging of sarcoma 180-bearing mice. Larger number of counts must be obtained within limited acquisition time to visualize tumor heterogeneity in vivo in animal imaging, compared to cases that simply detect tumors. At an acquisition time of 30 min, better image quality was obtained with pinhole apertures diameter of 1.4 mm than of 1.0 mm. The obtained best spatial resolution was 1.3 mm, it was acceptable for our purpose, though a little worse than the best possible performance of the scanner (1.0 mm). Additionally, the reconstruction parameters, such as noise suppression, voxel size, and iteration/subset number, needed to be optimized under the limited conditions and were different from those found under the ideal condition. The minimal radioactivity concentration for visualization of heterogeneous tumor interiors was estimated to be as high as 0.2-0.5 MBq/mL. Liposomes containing 111 In met this requirement and were administered to tumor-bearing mice. SPECT imaging successfully showed heterogeneous 111 In distribution within the tumors in vivo with good spatial resolution. A threshold of 0.2 MBq/g for clear visualization of tumor heterogeneity was validated. Autoradiograms obtained ex vivo of excised tumors confirmed that the in vivo SPECT images accurately depicted the heterogeneous intratumoral accumulation of liposomes. Intratumoral heterogeneity was successfully visualized under the optimized

Northeastern Regional Geologic Characterization Report: executive summary. Final report

International Nuclear Information System (INIS)

1985-08-01

This Executive Summary of the final Northeastern Regional Geologic Characterization Report (RGCR) is issued primarily for public information purposes and provides a general overview of the report. The complete RGCR presents available regional geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. For each of the states within the Northeastern Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. 5 refs., 3 figs

Heterogeneous High Throughput Scientific Computing with APM X-Gene and Intel Xeon Phi

CERN Document Server

Abdurachmanov, David; Elmer, Peter; Eulisse, Giulio; Knight, Robert; Muzaffar, Shahzad

2014-01-01

Electrical power requirements will be a constraint on the future growth of Distributed High Throughput Computing (DHTC) as used by High Energy Physics. Performance-per-watt is a critical metric for the evaluation of computer architectures for cost- efficient computing. Additionally, future performance growth will come from heterogeneous, many-core, and high computing density platforms with specialized processors. In this paper, we examine the Intel Xeon Phi Many Integrated Cores (MIC) co-processor and Applied Micro X-Gene ARMv8 64-bit low-power server system-on-a-chip (SoC) solutions for scientific computing applications. We report our experience on software porting, performance and energy efficiency and evaluate the potential for use of such technologies in the context of distributed computing systems such as the Worldwide LHC Computing Grid (WLCG).

Heterogeneous High Throughput Scientific Computing with APM X-Gene and Intel Xeon Phi

Science.gov (United States)

Abdurachmanov, David; Bockelman, Brian; Elmer, Peter; Eulisse, Giulio; Knight, Robert; Muzaffar, Shahzad

2015-05-01

Electrical power requirements will be a constraint on the future growth of Distributed High Throughput Computing (DHTC) as used by High Energy Physics. Performance-per-watt is a critical metric for the evaluation of computer architectures for cost- efficient computing. Additionally, future performance growth will come from heterogeneous, many-core, and high computing density platforms with specialized processors. In this paper, we examine the Intel Xeon Phi Many Integrated Cores (MIC) co-processor and Applied Micro X-Gene ARMv8 64-bit low-power server system-on-a-chip (SoC) solutions for scientific computing applications. We report our experience on software porting, performance and energy efficiency and evaluate the potential for use of such technologies in the context of distributed computing systems such as the Worldwide LHC Computing Grid (WLCG).

Heterogeneous High Throughput Scientific Computing with APM X-Gene and Intel Xeon Phi

International Nuclear Information System (INIS)

Abdurachmanov, David; Bockelman, Brian; Elmer, Peter; Eulisse, Giulio; Muzaffar, Shahzad; Knight, Robert

2015-01-01

Electrical power requirements will be a constraint on the future growth of Distributed High Throughput Computing (DHTC) as used by High Energy Physics. Performance-per-watt is a critical metric for the evaluation of computer architectures for cost- efficient computing. Additionally, future performance growth will come from heterogeneous, many-core, and high computing density platforms with specialized processors. In this paper, we examine the Intel Xeon Phi Many Integrated Cores (MIC) co-processor and Applied Micro X-Gene ARMv8 64-bit low-power server system-on-a-chip (SoC) solutions for scientific computing applications. We report our experience on software porting, performance and energy efficiency and evaluate the potential for use of such technologies in the context of distributed computing systems such as the Worldwide LHC Computing Grid (WLCG). (paper)

Theory of Pulsed Neutron Experiments in Highly Heterogeneous Multiplying Media

International Nuclear Information System (INIS)

Corno, S.E.

1965-01-01

In this work we investigate the time and space dependence of the neutron flux within a highly heterogeneous assembly, in which pulsed or sinusoidally modulated neutrons are injected. We consider, for the sake of simplicity, a device consisting of a cylindrical block of heavy moderator, along the axis of which a line-shaped region of fissionable material is located. The driving neutron source is assumed to be located on one of the end faces of the cylinder. The extent of the fissionable region allows us to deal with it as with an absorbing and multiplying singularity of the neutron field. As our attention is mostly concentrated on space and time variation of the neutron flux, rather crude approximations are assumed as far as the energy dependence of the neutron population is concerned. Within the limits of the age-diffusion theory, the response of the device to any neutron excitation may be found in closed form. For a sinusoidally modulated source of given frequency, it may easily be shown that, if the axial singularity were a purely absorbing one, the neutron waves being propagated along the device would possess a phase shift; a wavelength and an attenuation constant depending on the absorbing properties of the singularity. This picture becomes more and more complicated when neutron multiplication occurs. For this general case the solution derived in our paper obviously turns out to be dependent on both absorption and multiplication properties of the singularity. This circumstance suggests, among others, the idea of using a device of the type described above for testing fuel elements of heterogeneous reactors. (author) [fr

When high achievers and low achievers work in the same group: the roles of group heterogeneity and processes in project-based learning.

Science.gov (United States)

Cheng, Rebecca Wing-yi; Lam, Shui-fong; Chan, Joanne Chung-yan

2008-06-01

There has been an ongoing debate about the inconsistent effects of heterogeneous ability grouping on students in small group work such as project-based learning. The present research investigated the roles of group heterogeneity and processes in project-based learning. At the student level, we examined the interaction effect between students' within-group achievement and group processes on their self- and collective efficacy. At the group level, we examined how group heterogeneity was associated with the average self- and collective efficacy reported by the groups. The participants were 1,921 Hong Kong secondary students in 367 project-based learning groups. Student achievement was determined by school examination marks. Group processes, self-efficacy and collective efficacy were measured by a student-report questionnaire. Hierarchical linear modelling was used to analyse the nested data. When individual students in each group were taken as the unit of analysis, results indicated an interaction effect of group processes and students' within-group achievement on the discrepancy between collective- and self-efficacy. When compared with low achievers, high achievers reported lower collective efficacy than self-efficacy when group processes were of low quality. However, both low and high achievers reported higher collective efficacy than self-efficacy when group processes were of high quality. With 367 groups taken as the unit of analysis, the results showed that group heterogeneity, group gender composition and group size were not related to the discrepancy between collective- and self-efficacy reported by the students. Group heterogeneity was not a determinant factor in students' learning efficacy. Instead, the quality of group processes played a pivotal role because both high and low achievers were able to benefit when group processes were of high quality.

Clonal heterogeneity and chromosomal instability at disease presentation in high hyperdiploid acute lymphoblastic leukemia.

Science.gov (United States)

Talamo, Anna; Chalandon, Yves; Marazzi, Alfio; Jotterand, Martine

2010-12-01

Although aneuploidy has many possible causes, it often results from underlying chromosomal instability (CIN) leading to an unstable karyotype with cell-to-cell variation and multiple subclones. To test for the presence of CIN in high hyperdiploid acute lymphoblastic leukemia (HeH ALL) at diagnosis, we investigated 20 patients (10 HeH ALL and 10 non-HeH ALL), using automated four-color interphase fluorescence in situ hybridization (I-FISH) with centromeric probes for chromosomes 4, 6, 10, and 17. In HeH ALL, the proportion of abnormal cells ranged from 36.3% to 92.4%, and a variety of aneuploid populations were identified. Compared with conventional cytogenetics, I-FISH revealed numerous additional clones, some of them very small. To investigate the nature and origin of this clonal heterogeneity, we determined average numerical CIN values for all four chromosomes together and for each chromosome and patient group. The CIN values in HeH ALL were relatively high (range, 22.2-44.7%), compared with those in non-HeH ALL (3.2-6.4%), thus accounting for the presence of numerical CIN in HeH ALL at diagnosis. We conclude that numerical CIN may be at the origin of the high level of clonal heterogeneity revealed by I-FISH in HeH ALL at presentation, which would corroborate the potential role of CIN in tumor pathogenesis. Copyright © 2010 Elsevier Inc. All rights reserved.

Geographical distribution patterns of iodine in drinking-water and its associations with geological factors in Shandong Province, China.

Science.gov (United States)

Gao, Jie; Zhang, Zhijie; Hu, Yi; Bian, Jianchao; Jiang, Wen; Wang, Xiaoming; Sun, Liqian; Jiang, Qingwu

2014-05-19

County-based spatial distribution characteristics and the related geological factors for iodine in drinking-water were studied in Shandong Province (China). Spatial autocorrelation analysis and spatial scan statistic were applied to analyze the spatial characteristics. Generalized linear models (GLMs) and geographically weighted regression (GWR) studies were conducted to explore the relationship between water iodine level and its related geological factors. The spatial distribution of iodine in drinking-water was significantly heterogeneous in Shandong Province (Moran's I = 0.52, Z = 7.4, p water were identified in the south-western and north-western parts of Shandong Province by the purely spatial scan statistic approach. Both GLMs and GWR indicated a significantly global association between iodine in drinking-water and geological factors. Furthermore, GWR showed obviously spatial variability across the study region. Soil type and distance to Yellow River were statistically significant at most areas of Shandong Province, confirming the hypothesis that the Yellow River causes iodine deposits in Shandong Province. Our results suggested that the more effective regional monitoring plan and water improvement strategies should be strengthened targeting at the cluster areas based on the characteristics of geological factors and the spatial variability of local relationships between iodine in drinking-water and geological factors.

Geoethics and Forensic Geology

Science.gov (United States)

Donnelly, Laurance

2017-04-01

The International Union of Geological Sciences (IUGS), Initiative on Forensic Geology (IFG) was set up in 2011 to promote and develop the applications of geology to policing and law enforcement throughout the world. This includes the provision of crime scene examinations, searches to locate graves or items of interest that have been buried beneath the ground surface as part of a criminal act and geological trace analysis and evidence. Forensic geologists may assist the police and law enforcement in a range of ways including for example; homicide, sexual assaults, counter terrorism, kidnapping, humanitarian incidents, environmental crimes, precious minerals theft, fakes and fraudulent crimes. The objective of this paper is to consider the geoethical aspects of forensic geology. This includes both delivery to research and teaching, and contribution to the practical applications of forensic geology in case work. The case examples cited are based on the personal experiences of the authors. Often, the technical and scientific aspect of forensic geology investigation may be the most straightforward, after all, this is what the forensic geologist has been trained to do. The associated geoethical issues can be the most challenging and complex to manage. Generally, forensic geologists are driven to carry-out their research or case work with integrity, honesty and in a manner that is law abiding, professional, socially acceptable and highly responsible. This is necessary in advising law enforcement organisations, society and the scientific community that they represent. As the science of forensic geology begins to advance around the world it is desirable to establish a standard set of principles, values and to provide an agreed ethical a framework. But what are these core values? Who is responsible for producing these? How may these become enforced? What happens when geoethical standards are breached? This paper does not attempt to provide all of the answers, as further work

Integrated reservoir characterization: Improvement in heterogeneities stochastic modelling by integration of additional external constraints

Energy Technology Data Exchange (ETDEWEB)

Doligez, B.; Eschard, R. [Institut Francais du Petrole, Rueil Malmaison (France); Geffroy, F. [Centre de Geostatistique, Fontainebleau (France)] [and others

1997-08-01

The classical approach to construct reservoir models is to start with a fine scale geological model which is informed with petrophysical properties. Then scaling-up techniques allow to obtain a reservoir model which is compatible with the fluid flow simulators. Geostatistical modelling techniques are widely used to build the geological models before scaling-up. These methods provide equiprobable images of the area under investigation, which honor the well data, and which variability is the same than the variability computed from the data. At an appraisal phase, when few data are available, or when the wells are insufficient to describe all the heterogeneities and the behavior of the field, additional constraints are needed to obtain a more realistic geological model. For example, seismic data or stratigraphic models can provide average reservoir information with an excellent areal coverage, but with a poor vertical resolution. New advances in modelisation techniques allow now to integrate this type of additional external information in order to constrain the simulations. In particular, 2D or 3D seismic derived information grids, or sand-shale ratios maps coming from stratigraphic models can be used as external drifts to compute the geological image of the reservoir at the fine scale. Examples are presented to illustrate the use of these new tools, their impact on the final reservoir model, and their sensitivity to some key parameters.

Large epidemic thresholds emerge in heterogeneous networks of heterogeneous nodes

Science.gov (United States)

Yang, Hui; Tang, Ming; Gross, Thilo

2015-08-01

One of the famous results of network science states that networks with heterogeneous connectivity are more susceptible to epidemic spreading than their more homogeneous counterparts. In particular, in networks of identical nodes it has been shown that network heterogeneity, i.e. a broad degree distribution, can lower the epidemic threshold at which epidemics can invade the system. Network heterogeneity can thus allow diseases with lower transmission probabilities to persist and spread. However, it has been pointed out that networks in which the properties of nodes are intrinsically heterogeneous can be very resilient to disease spreading. Heterogeneity in structure can enhance or diminish the resilience of networks with heterogeneous nodes, depending on the correlations between the topological and intrinsic properties. Here, we consider a plausible scenario where people have intrinsic differences in susceptibility and adapt their social network structure to the presence of the disease. We show that the resilience of networks with heterogeneous connectivity can surpass those of networks with homogeneous connectivity. For epidemiology, this implies that network heterogeneity should not be studied in isolation, it is instead the heterogeneity of infection risk that determines the likelihood of outbreaks.

Large epidemic thresholds emerge in heterogeneous networks of heterogeneous nodes.

Science.gov (United States)

Yang, Hui; Tang, Ming; Gross, Thilo

2015-08-21

One of the famous results of network science states that networks with heterogeneous connectivity are more susceptible to epidemic spreading than their more homogeneous counterparts. In particular, in networks of identical nodes it has been shown that network heterogeneity, i.e. a broad degree distribution, can lower the epidemic threshold at which epidemics can invade the system. Network heterogeneity can thus allow diseases with lower transmission probabilities to persist and spread. However, it has been pointed out that networks in which the properties of nodes are intrinsically heterogeneous can be very resilient to disease spreading. Heterogeneity in structure can enhance or diminish the resilience of networks with heterogeneous nodes, depending on the correlations between the topological and intrinsic properties. Here, we consider a plausible scenario where people have intrinsic differences in susceptibility and adapt their social network structure to the presence of the disease. We show that the resilience of networks with heterogeneous connectivity can surpass those of networks with homogeneous connectivity. For epidemiology, this implies that network heterogeneity should not be studied in isolation, it is instead the heterogeneity of infection risk that determines the likelihood of outbreaks.

Field Geology/Processes

Science.gov (United States)

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.

The development of safeguards for geological repositories

International Nuclear Information System (INIS)

Van der Meer, K.

2009-01-01

Traditionally, research and development on geological repositories for High Level Waste (HLW) focuses on the short- and long-term safety aspects of the repository. If the repository will also be used for the disposal of spent fuel, safeguards aspects have to be taken into account. Safety and safeguards requirements may be contradictory; the safety of a geological repository is based on the non-intrusion of the geological containment, while safeguards require regular inspections of position and amount of the spent fuel. Examples to reconcile these contradictory requirements are the use of information required for the safety assessment of the geological repository for safeguards purposes and the adaptation of the safeguards approach to use non-intrusive inspection techniques. The principles of an inspection approach for a geological repository are now generally accepted within the IAEA. The practical applicability of the envisaged inspection techniques is still subject to investigation. It is specifically important for the Belgian situation that an inspection technique can be used in clay, the geological medium in which Belgium intends to dispose its HLW and spent fuel. The work reported in this chapter is the result of an international cooperation in the framework of the IAEA, in which SCK-CEN participates

Geology Laxemar. Site descriptive modelling SDM-Site Laxemar

International Nuclear Information System (INIS)

Wahlgren, Carl-Henric; Curtis, Philip; Hermanson, Jan; Forssberg, Ola; Oehman, Johan; Fox, Aaron; La Pointe, Paul; Drake, Henrik; Triumf, Carl-Axel; Mattsson, Haakan; Thunehed, Hans; Juhlin, Christopher

2008-11-01

, kinematics of brittle deformation in drill cores and outcrops, as well as studies with particular focus on minor deformation zones (MDZ) in both drill cores and in the field. Complementary geochronological and other rock and fracture analytical data. High resolution airborne laser scanning (LIDAR) leading to a new digital elevation model (DEM) together with high-resolution ground magnetic and resistivity data providing the basis for further lineament interpretations. Further seismic refraction surveys and reprocessing and re-evaluation of seismic reflection data. The outputs of the deterministic modelling work are geometric models in RVS format for rock domains, deformation zones and fracture domains, including detailed property tables for rock domains and deformation zones and a description of fracture domains. The outputs of the geological DFN modelling process are recommended parameters or statistical distributions that describe fracture set orientations, sizes, volumetric intensities, spatial correlations and models, and other parameters (lithology and scaling corrections, termination matrices) that are necessary for building stochastic models. The regional scale ductile deformation zones strike NNE-SSW and NE-SW, are subvertical and are characterised by sinistral strike-slip displacements, while E-W oriented zones, though more strongly overprinted by brittle deformation, display moderate to steep dips to the south or north. The kinematics of the latter are not resolved at Laxemar, but E-W ductile shear zones in the Simpevarp subarea show complex kinematics, including both reverse and normal dip-slip as well as sinistral and dextral strike-slip displacements. It should be noted that the regional and local major deformation zones, although the majority have a ductile precursor, are mainly brittle in character. The focussed volume is transected by a series of smaller deformation zones with a variety of orientations and with dips varying from sub-vertical to sub

Rapid analysis of heterogeneously methylated DNA using digital methylation-sensitive high resolution melting: application to the CDKN2B (p15) gene

DEFF Research Database (Denmark)

Candiloro, Ida Lm; Mikeska, Thomas; Hokland, Peter

2008-01-01

ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (dMS-HRM) t......ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (d......MS-HRM) that involves the amplification of single templates after limiting dilution to quantify and to determine the degree of methylation. We used this approach to study methylation of the CDKN2B (p15) cell cycle progression inhibitor gene which is inactivated by DNA methylation in haematological malignancies...... the methylated alleles and assess the degree of methylation. Direct sequencing of selected dMS-HRM products was used to determine the exact DNA methylation pattern and confirmed the degree of methylation estimated by dMS-HRM. CONCLUSION: dMS-HRM is a powerful technique for the analysis of methylation in CDKN2B...

Bedrock geology Forsmark. Modelling stage 2.3. Implications for and verification of the deterministic geological models based on complementary data

Energy Technology Data Exchange (ETDEWEB)

Stephens, Michael B. (Geological Survey of Sweden, Uppsala (Sweden)); Simeonov, Assen (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Isaksson, Hans (GeoVista AB, Luleaa (Sweden))

2008-12-15

The Swedish Nuclear Fuel and Waste Management Company is in the process of completing site descriptive modelling at two locations in Sweden, with the objective to site a deep geological repository for spent nuclear fuel. At Forsmark, the results of the stage 2.2 geological modelling formed the input for downstream users. Since complementary ground and borehole geological and geophysical data, acquired after model stage 2.2, were not planned to be included in the deterministic rock domain, fracture domain and deformation zone models supplied to the users, it was deemed necessary to evaluate the implications of these stage 2.3 data for the stage 2.2 deterministic geological models and, if possible, to make use of these data to verify the models. This report presents the results of the analysis of the complementary stage 2.3 geological and geophysical data. Model verification from borehole data has been implemented in the form of a prediction-outcome test. The stage 2.3 geological and geophysical data at Forsmark mostly provide information on the bedrock outside the target volume. Additional high-resolution ground magnetic data and the data from the boreholes KFM02B, KFM11A, KFM12A and HFM33 to HFM37 can be included in this category. Other data complement older information of identical character, both inside and outside this volume. These include the character and kinematics of deformation zones and fracture mineralogy. In general terms, it can be stated that all these new data either confirm the geological modelling work completed during stage 2.2 or are in good agreement with the data that were used in this work. In particular, although the new high-resolution ground magnetic data modify slightly the position and trace length of some stage 2.2 deformation zones at the ground surface, no new or modified deformation zones with a trace length longer than 3,000 m at the ground surface have emerged. It is also apparent that the revision of fracture orientation data

Bedrock geology Forsmark. Modelling stage 2.3. Implications for and verification of the deterministic geological models based on complementary data

International Nuclear Information System (INIS)

Stephens, Michael B.; Simeonov, Assen; Isaksson, Hans

2008-12-01

The Swedish Nuclear Fuel and Waste Management Company is in the process of completing site descriptive modelling at two locations in Sweden, with the objective to site a deep geological repository for spent nuclear fuel. At Forsmark, the results of the stage 2.2 geological modelling formed the input for downstream users. Since complementary ground and borehole geological and geophysical data, acquired after model stage 2.2, were not planned to be included in the deterministic rock domain, fracture domain and deformation zone models supplied to the users, it was deemed necessary to evaluate the implications of these stage 2.3 data for the stage 2.2 deterministic geological models and, if possible, to make use of these data to verify the models. This report presents the results of the analysis of the complementary stage 2.3 geological and geophysical data. Model verification from borehole data has been implemented in the form of a prediction-outcome test. The stage 2.3 geological and geophysical data at Forsmark mostly provide information on the bedrock outside the target volume. Additional high-resolution ground magnetic data and the data from the boreholes KFM02B, KFM11A, KFM12A and HFM33 to HFM37 can be included in this category. Other data complement older information of identical character, both inside and outside this volume. These include the character and kinematics of deformation zones and fracture mineralogy. In general terms, it can be stated that all these new data either confirm the geological modelling work completed during stage 2.2 or are in good agreement with the data that were used in this work. In particular, although the new high-resolution ground magnetic data modify slightly the position and trace length of some stage 2.2 deformation zones at the ground surface, no new or modified deformation zones with a trace length longer than 3,000 m at the ground surface have emerged. It is also apparent that the revision of fracture orientation data

Global Journal of Geological Sciences

African Journals Online (AJOL)

Global Journal of Geological Sciences is aimed at promoting research in all areas of Geological Sciences including geochemistry, geophysics, engineering geology, hydrogeology, petrology, mineralogy, geochronology, tectonics, mining, structural geology, marine geology, space science etc. Visit the Global Journal Series ...

Modeling Transport of Cesium in Grimsel Granodiorite With Micrometer Scale Heterogeneities and Dynamic Update of Kd

Science.gov (United States)

Voutilainen, Mikko; Kekäläinen, Pekka; Siitari-Kauppi, Marja; Sardini, Paul; Muuri, Eveliina; Timonen, Jussi; Martin, Andrew

2017-11-01

Transport and retardation of cesium in Grimsel granodiorite taking into account heterogeneity of mineral and pore structure was studied using rock samples overcored from an in situ diffusion test at the Grimsel Test Site. The field test was part of the Long-Term Diffusion (LTD) project designed to characterize retardation properties (diffusion and distribution coefficients) under in situ conditions. Results of the LTD experiment for cesium showed that in-diffusion profiles and spatial concentration distributions were strongly influenced by the heterogeneous pore structure and mineral distribution. In order to study the effect of heterogeneity on the in-diffusion profile and spatial concentration distribution, a Time Domain Random Walk (TDRW) method was applied along with a feature for modeling chemical sorption in geological materials. A heterogeneous mineral structure of Grimsel granodiorite was constructed using X-ray microcomputed tomography (X-μCT) and the map was linked to previous results for mineral specific porosities and distribution coefficients (Kd) that were determined using C-14-PMMA autoradiography and batch sorption experiments, respectively. After this the heterogeneous structure contains information on local porosity and Kd in 3-D. It was found that the heterogeneity of the mineral structure on the micrometer scale affects significantly the diffusion and sorption of cesium in Grimsel granodiorite at the centimeter scale. Furthermore, the modeled in-diffusion profiles and spatial concentration distributions show similar shape and pattern to those from the LTD experiment. It was concluded that the use of detailed structure characterization and quantitative data on heterogeneity can significantly improve the interpretation and evaluation of transport experiments.

Use of the ion microprobe in geological dating

International Nuclear Information System (INIS)

Compston, W.; Williams, I.S.; Black, L.P.

1983-01-01

SHRIMP, the Sensitive High Resolution Ion Microprobe with computerised control and data acquisition system, has recently been commissioned. It is used within the Research School of Earth Sciences, Australian National University, for the isotopic analysis of geological samples. Principles of operation and geological applications are outlined. One example described is the application to Pb-U dating of zircon

The JAERI program for development of safety assessment models and acquisition of data needed for assessment of geological disposal of high-level radioactive wastes

International Nuclear Information System (INIS)

Matsuzuru, H.

1991-01-01

The JAERI is conducting R and D program for the development of safety assessment methodologies and the acquisition of data needed for the assessment of geologic disposal of high-level radioactive wastes, aiming at the elucidation of feasibility of geologic disposal in Japan. The paper describes current R and D activities to develop interim versions of both a deterministic and a probabilistic methodologies based on a normal evolution scenario, to collect data concerning engineered barriers and geologic media through field and laboratory experiments, and to validate the models used in the methodologies. 2 figs., 2 refs

On the validity of effective formulations for transport through heterogeneous porous media

Science.gov (United States)

de Dreuzy, Jean-Raynald; Carrera, Jesus

2016-04-01

Geological heterogeneity enhances spreading of solutes and causes transport to be anomalous (i.e., non-Fickian), with much less mixing than suggested by dispersion. This implies that modeling transport requires adopting either stochastic approaches that model heterogeneity explicitly or effective transport formulations that acknowledge the effects of heterogeneity. A number of such formulations have been developed and tested as upscaled representations of enhanced spreading. However, their ability to represent mixing has not been formally tested, which is required for proper reproduction of chemical reactions and which motivates our work. We propose that, for an effective transport formulation to be considered a valid representation of transport through heterogeneous porous media (HPM), it should honor mean advection, mixing and spreading. It should also be flexible enough to be applicable to real problems. We test the capacity of the multi-rate mass transfer (MRMT) model to reproduce mixing observed in HPM, as represented by the classical multi-Gaussian log-permeability field with a Gaussian correlation pattern. Non-dispersive mixing comes from heterogeneity structures in the concentration fields that are not captured by macrodispersion. These fine structures limit mixing initially, but eventually enhance it. Numerical results show that, relative to HPM, MRMT models display a much stronger memory of initial conditions on mixing than on dispersion because of the sensitivity of the mixing state to the actual values of concentration. Because MRMT does not restitute the local concentration structures, it induces smaller non-dispersive mixing than HPM. However long-lived trapping in the immobile zones may sustain the deviation from dispersive mixing over much longer times. While spreading can be well captured by MRMT models, in general non-dispersive mixing cannot.

Introductory Geology From the Liberal Arts Approach: A Geology-Sociology Linked Course

Science.gov (United States)

Walsh, E. O.; Davis, E.

2008-12-01

Geology can be a hard sell to college students, especially to college students attending small, liberal arts institutions in localities that lack exaggerated topography. At these schools, Geology departments that wish to grow must work diligently to attract students to the major; professors must be able to convince a wider audience of students that geology is relevant to their everyday lives. Toward this end, a Physical Geology course was linked with an introductory Sociology course through the common theme of Consumption. The same students took the two courses in sequence, beginning with the Sociology course and ending with Physical Geology; thus, students began by discussing the role of consumption in society and ended by learning about the geological processes and implications of consumption. Students were able to ascertain the importance of geology in their daily lives by connecting Earth processes to specific products they consume, such as cell phones and bottled water. Students were also able to see the connection between seemingly disparate fields of study, which is a major goal of the liberal arts. As a theme, Consumption worked well to grab the attention of students interested in diverse issues, such as environmental science or social justice. A one-hour lecture illustrating the link between sociology and geology was developed for presentation to incoming freshmen and their parents to advertise the course. Initial response has been positive, showing an increase in awareness of geological processes among students with a wide range of interests.

North Central Regional Geologic Characterization Report. Executive summary. Final report

International Nuclear Information System (INIS)

1985-08-01

This Executive Summary of the final North Central Regional Geologic Characterization Report (RGCR) is issued primarily for public information purposes and provides a general overview of the report. The complete RGCR presents available regional geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening

Temperature dependent heterogeneous rotational correlation in lipids.

Science.gov (United States)

Dadashvand, Neda; Othon, Christina M

2016-11-15

Lipid structures exhibit complex and highly dynamic lateral structure; and changes in lipid density and fluidity are believed to play an essential role in membrane targeting and function. The dynamic structure of liquids on the molecular scale can exhibit complex transient density fluctuations. Here the lateral heterogeneity of lipid dynamics is explored in free standing lipid monolayers. As the temperature is lowered the probes exhibit increasingly broad and heterogeneous rotational correlation. This increase in heterogeneity appears to exhibit a critical onset, similar to those observed for glass forming fluids. We explore heterogeneous relaxation in in a single constituent lipid monolayer of 1, 2-dimyristoyl-sn-glycero-3-phosphocholine  by measuring the rotational diffusion of a fluorescent probe (1-palmitoyl-2-[1]-sn-glycero-3-phosphocholine), which is embedded in the lipid monolayer at low labeling density. Dynamic distributions are measured using wide-field time-resolved fluorescence anisotropy. The observed relaxation exhibits a narrow, liquid-like distribution at high temperatures (τ ∼ 2.4 ns), consistent with previous experimental measures (Dadashvand et al 2014 Struct. Dyn. 1 054701, Loura and Ramalho 2007 Biochim. Biophys. Acta 1768 467-478). However, as the temperature is quenched, the distribution broadens, and we observe the appearance of a long relaxation population (τ ∼ 16.5 ns). This supports the heterogeneity observed for lipids at high packing densities, and demonstrates that the nanoscale diffusion and reorganization in lipid structures can be significantly complex, even in the simplest amorphous architectures. Dynamical heterogeneity of this form can have a significant impact on the organization, permeability and energetics of lipid membrane structures.

Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste: Proceedings

International Nuclear Information System (INIS)

Kovach, L.A.; Murphy, W.M.

1995-09-01

A Workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste was held in San Antonio, Texas on July 22--25, 1991. The proceedings comprise seventeen papers submitted by participants at the workshop. A series of papers addresses the relation of natural analog studies to the regulation, performance assessment, and licensing of a geologic repository. Applications of reasoning by analogy are illustrated in papers on the role of natural analogs in studies of earthquakes, petroleum, and mineral exploration. A summary is provided of a recently completed, internationally coordinated natural analog study at Pocos de Caldas, Brazil. Papers also cover problems and applications of natural analog studies in four technical areas of nuclear waste management-. waste form and waste package, near-field processes and environment, far-field processes and environment, and volcanism and tectonics. Summaries of working group deliberations in these four technical areas provide reviews and proposals for natural analog applications. Individual papers have been cataloged separately

Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste: Proceedings

Energy Technology Data Exchange (ETDEWEB)

Kovach, L.A. [ed.] [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications; Murphy, W.M. [ed.] [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

1995-09-01

A Workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste was held in San Antonio, Texas on July 22--25, 1991. The proceedings comprise seventeen papers submitted by participants at the workshop. A series of papers addresses the relation of natural analog studies to the regulation, performance assessment, and licensing of a geologic repository. Applications of reasoning by analogy are illustrated in papers on the role of natural analogs in studies of earthquakes, petroleum, and mineral exploration. A summary is provided of a recently completed, internationally coordinated natural analog study at Pocos de Caldas, Brazil. Papers also cover problems and applications of natural analog studies in four technical areas of nuclear waste management-. waste form and waste package, near-field processes and environment, far-field processes and environment, and volcanism and tectonics. Summaries of working group deliberations in these four technical areas provide reviews and proposals for natural analog applications. Individual papers have been cataloged separately.

Corrosion behaviour of container materials for geological disposal of high level radioactive waste

International Nuclear Information System (INIS)

Accary, A.

1985-01-01

The disposal of high level radioactive waste in geological formations, based on the multibarrier concept, may include the use of a container as one of the engineered barriers. In this report the requirements imposed on this container and the possible degradation processes are reviewed. Further on an overview is given of the research being carried out by various research centres in the European Community on the assessment of the corrosion behaviour of candidate container materials. The results obtained on a number of materials under various testing conditions are summarized and evaluated. As a result, three promising materials have been selected for a detailed joint testing programme. It concerns two highly corrosion resistant alloys, resp. Ti-Pd (0.2 Pd%) and Hastelloy C4 and one consumable material namely a low carbon steel. Finally the possibilities of modelling the corrosion phenomena are discussed

Digital Geologic Mapping and Integration with the Geoweb: The Death Knell for Exclusively Paper Geologic Maps

Science.gov (United States)

House, P. K.

2008-12-01

The combination of traditional methods of geologic mapping with rapidly developing web-based geospatial applications ('the geoweb') and the various collaborative opportunities of web 2.0 have the potential to change the nature, value, and relevance of geologic maps and related field studies. Parallel advances in basic GPS technology, digital photography, and related integrative applications provide practicing geologic mappers with greatly enhanced methods for collecting, visualizing, interpreting, and disseminating geologic information. Even a cursory application of available tools can make field and office work more enriching and efficient; whereas more advanced and systematic applications provide new avenues for collaboration, outreach, and public education. Moreover, they ensure a much broader audience among an immense number of internet savvy end-users with very specific expectations for geospatial data availability. Perplexingly, the geologic community as a whole is not fully exploring this opportunity despite the inevitable revolution in portends. The slow acceptance follows a broad generational trend wherein seasoned professionals are lagging behind geology students and recent graduates in their grasp of and interest in the capabilities of the geoweb and web 2.0 types of applications. Possible explanations for this include: fear of the unknown, fear of learning curve, lack of interest, lack of academic/professional incentive, and (hopefully not) reluctance toward open collaboration. Although some aspects of the expanding geoweb are cloaked in arcane computer code, others are extremely simple to understand and use. A particularly obvious and simple application to enhance any field study is photo geotagging, the digital documentation of the locations of key outcrops, illustrative vistas, and particularly complicated geologic field relations. Viewing geotagged photos in their appropriate context on a virtual globe with high-resolution imagery can be an

Highly Dispersed Pseudo-Homogeneous and Heterogeneous Catalysts Synthesized via Inverse Micelle Solutions for the Liquefaction of Coal

Energy Technology Data Exchange (ETDEWEB)

Hampden-Smith, M.; Kawola, J.S.; Martino, A.; Sault, A.G.; Yamanaka, S.A.

1999-01-05

The mission of this project was to use inverse micelle solutions to synthesize nanometer sized metal particles and test the particles as catalysts in the liquefaction of coal and other related reactions. The initial focus of the project was the synthesis of iron based materials in pseudo-homogeneous form. The frost three chapters discuss the synthesis, characterization, and catalyst testing in coal liquefaction and model coal liquefaction reactions of iron based pseudo-homogeneous materials. Later, we became interested in highly dispersed catalysts for coprocessing of coal and plastic waste. Bifunctional catalysts . to hydrogenate the coal and depolymerize the plastic waste are ideal. We began studying, based on our previously devised synthesis strategies, the synthesis of heterogeneous catalysts with a bifunctional nature. In chapter 4, we discuss the fundamental principles in heterogeneous catalysis synthesis with inverse micelle solutions. In chapter 5, we extend the synthesis of chapter 4 to practical systems and use the materials in catalyst testing. Finally in chapter 6, we return to iron and coal liquefaction now studied with the heterogeneous catalysts.

Geological, geochemical, and geophysical studies by the U.S. Geological Survey in Big Bend National Park, Texas

Science.gov (United States)

Page, W.R.; Turner, K.J.; Bohannon, R.G.; Berry, M.E.; Williams, V.S.; Miggins, D.P.; Ren, M.; Anthony, E.Y.; Morgan, L.A.; Shanks, P.W.C.; Gray, J. E.; Theodorakos, P.M.; Krabbenhoft, D. P.; Manning, A.H.; Gemery-Hill, P. A.; Hellgren, E.C.; Stricker, C.A.; Onorato, D.P.; Finn, C.A.; Anderson, E.; Gray, J. E.; Page, W.R.

2008-01-01

Big Bend National Park (BBNP), Tex., covers 801,163 acres (3,242 km2) and was established in 1944 through a transfer of land from the State of Texas to the United States. The park is located along a 118-mile (190-km) stretch of the Rio Grande at the United States-Mexico border. The park is in the Chihuahuan Desert, an ecosystem with high mountain ranges and basin environments containing a wide variety of native plants and animals, including more than 1,200 species of plants, more than 450 species of birds, 56 species of reptiles, and 75 species of mammals. In addition, the geology of BBNP, which varies widely from high mountains to broad open lowland basins, also enhances the beauty of the park. For example, the park contains the Chisos Mountains, which are dominantly composed of thick outcrops of Tertiary extrusive and intrusive igneous rocks that reach an altitude of 7,832 ft (2,387 m) and are considered the southernmost mountain range in the United States. Geologic features in BBNP provide opportunities to study the formation of mineral deposits and their environmental effects; the origin and formation of sedimentary and igneous rocks; Paleozoic, Mesozoic, and Cenozoic fossils; and surface and ground water resources. Mineral deposits in and around BBNP contain commodities such as mercury (Hg), uranium (U), and fluorine (F), but of these, the only significant mining has been for Hg. Because of the biological and geological diversity of BBNP, more than 350,000 tourists visit the park each year. The U.S. Geological Survey (USGS) has been investigating a number of broad and diverse geologic, geochemical, and geophysical topics in BBNP to provide fundamental information needed by the National Park Service (NPS) to address resource management goals in this park. Scientists from the USGS Mineral Resources and National Cooperative Geologic Mapping Programs have been working cooperatively with the NPS and several universities on several research studies within BBNP

Functional Heterogeneity and Senior Management Team Effectiveness

Science.gov (United States)

Benoliel, Pascale; Somech, Anit

2016-01-01

Purpose: There has been an increasing trend toward the creation of senior management teams (SMTs) which are characterized by a high degree of functional heterogeneity. Although such teams may create better linkages to information, along with the benefits of functional heterogeneity comes the potential for conflicts that stem from the value…

Detection of admittivity anomaly on high-contrast heterogeneous backgrounds using frequency difference EIT.

Science.gov (United States)

Jang, J; Seo, J K

2015-06-01

This paper describes a multiple background subtraction method in frequency difference electrical impedance tomography (fdEIT) to detect an admittivity anomaly from a high-contrast background conductivity distribution. The proposed method expands the use of the conventional weighted frequency difference EIT method, which has been used limitedly to detect admittivity anomalies in a roughly homogeneous background. The proposed method can be viewed as multiple weighted difference imaging in fdEIT. Although the spatial resolutions of the output images by fdEIT are very low due to the inherent ill-posedness, numerical simulations and phantom experiments of the proposed method demonstrate its feasibility to detect anomalies. It has potential application in stroke detection in a head model, which is highly heterogeneous due to the skull.

Exploring heterogeneous market hypothesis using realized volatility

Science.gov (United States)

Chin, Wen Cheong; Isa, Zaidi; Mohd Nor, Abu Hassan Shaari

2013-04-01

This study investigates the heterogeneous market hypothesis using high frequency data. The cascaded heterogeneous trading activities with different time durations are modelled by the heterogeneous autoregressive framework. The empirical study indicated the presence of long memory behaviour and predictability elements in the financial time series which supported heterogeneous market hypothesis. Besides the common sum-of-square intraday realized volatility, we also advocated two power variation realized volatilities in forecast evaluation and risk measurement in order to overcome the possible abrupt jumps during the credit crisis. Finally, the empirical results are used in determining the market risk using the value-at-risk approach. The findings of this study have implications for informationally market efficiency analysis, portfolio strategies and risk managements.

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

DEFF Research Database (Denmark)

Milosevic, Nemanja; Thomsen, Nanna Isbak; Juhler, R.K.

2012-01-01

Contaminants 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 hydrogeol...... 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....

Neurobiological heterogeneity in ADHD

NARCIS (Netherlands)

de Zeeuw, P.

2011-01-01

Attention-Deficit/Hyperactivity Disorder (ADHD) is a highly heterogeneous disorder clinically. Symptoms take many forms, from subtle but pervasive attention problems or dreaminess up to disruptive and unpredictable behavior. Interestingly, early neuroscientific work on ADHD assumed either a

Geological aspects of the nuclear waste disposal problem

International Nuclear Information System (INIS)

Laverov, N.P.; Omelianenko, B.L.; Velichkin, V.I.

1994-06-01

For the successful solution of the high-level waste (HLW) problem in Russia one must take into account such factors as the existence of the great volume of accumulated HLW, the large size and variety of geological conditions in the country, and the difficult economic conditions. The most efficient method of HLW disposal consists in the maximum use of protective capacities of the geological environment and in using inexpensive natural minerals for engineered barrier construction. In this paper, the principal trends of geological investigation directed toward the solution of HLW disposal are considered. One urgent practical aim is the selection of sites in deep wells in regions where the HLW is now held in temporary storage. The aim of long-term investigations into HLW disposal is to evaluate geological prerequisites for regional HLW repositories

A preliminary study on the regional fracture systems for deep geological disposal of high level radioactive waste in Korea

Energy Technology Data Exchange (ETDEWEB)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Young Kown; Park, Byoung Yoon [Korea Atomic Energy Research Institute, Taejeon (Korea)

2000-03-01

For the deep geological disposal of high-level radioactive waste, it is essential to characterize the fracture system in rock mass which has a potential pathways of nuclide. Currently, none of research results are in classification and detailed properties for the fracture system in Korea. This study aims to classify and describe the regional fracture system in lithological and geotectonical point of view using literature review, shaded relief map, and aeromagnetic survey data. This report contains the following: - Theoretical review of the fracture development mechanism. - Overall fault and fracture map. - Geological description on the distributional characteristics of faults and fractures(zone) in terms of lithological domain and tectonical province. 122 refs., 22 figs., 4 tabs. (Author)

Synthetic Study on the Geological and Hydrogeological Model around KURT

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Su; Koh, Yong Kwon; Choi, Jong Won

2011-01-01

To characterize the site specific properties of a study area for high-level radioactive waste disposal research in KAERI, the several geological investigations such as surface geological surveys and borehole drillings were carried out since 1997. Especially, KURT (KAERI Underground Research Tunnel) was constructed to understand the further study of geological environments in 2006. As a result, the first geological model of a study area was constructed by using the results of geological investigation. The objective of this research is to construct a hydrogeological model around KURT area on the basis of the geological model. Hydrogeological data which were obtained from in-situ hydraulic tests in the 9 boreholes were estimated to accomplish the objective. And, the hydrogeological properties of the 4 geological elements in the geological model, which were the subsurface weathering zone, the log angle fracture zone, the fracture zones and the bedrock were suggested. The hydrogeological model suggested in this study will be used as input parameters to carry out the groundwater flow modeling as a next step of the site characterization around KURT area

Geological exploration of Angola from Sumbe to Namibe: A review at the frontier between geology, natural resources and the history of geology

Science.gov (United States)

Masse, Pierre; Laurent, Olivier

2016-01-01

This paper provides a review of the Geological exploration of the Angola Coast (from Sumbe to Namibe) from pioneer's first geological descriptions and mining inventory to the most recent publications supported by the oil industry. We focus our attention on the following periods: 1875-1890 (Paul Choffat's work, mainly), 1910-1949 (first maps at country scale), 1949-1974 (detailed mapping of the Kwanza-Namibe coastal series), 1975-2000, with the editing of the last version of the Angola geological map at 1:1 million scale and the progressive completion of previous works. Since 2000, there is a renewal in geological fieldwork publications on the area mainly due to the work of university teams. This review paper thus stands at the frontier between geology, natural resources and the history of geology. It shows how geological knowledge has progressed in time, fueled by economic and scientific reasons.

Measuring the effects of heterogeneity on distributed systems

Science.gov (United States)

El-Toweissy, Mohamed; Zeineldine, Osman; Mukkamala, Ravi

1991-01-01

Distributed computer systems in daily use are becoming more and more heterogeneous. Currently, much of the design and analysis studies of such systems assume homogeneity. This assumption of homogeneity has been mainly driven by the resulting simplicity in modeling and analysis. A simulation study is presented which investigated the effects of heterogeneity on scheduling algorithms for hard real time distributed systems. In contrast to previous results which indicate that random scheduling may be as good as a more complex scheduler, this algorithm is shown to be consistently better than a random scheduler. This conclusion is more prevalent at high workloads as well as at high levels of heterogeneity.

Quantifying uncertainty of geological 3D layer models, constructed with a-priori geological expertise

NARCIS (Netherlands)

Gunnink, J.J.; Maljers, D.; Hummelman, J.

2010-01-01

Uncertainty quantification of geological models that are constructed with additional geological expert-knowledge is not straightforward. To construct sound geological 3D layer models we use a lot of additional knowledge, with an uncertainty that is hard to quantify. Examples of geological expert

High-resolution observations of combustion in heterogeneous surface fuels

Science.gov (United States)

E. Louise Loudermilk; Gary L. Achtemeier; Joseph J. O' Brien; J. Kevin Hiers; Benjamin S. Hornsby

2014-01-01

In ecosystems with frequent surface fires, fire and fuel heterogeneity at relevant scales have been largely ignored. This could be because complete burns give an impression of homogeneity, or due to the difficulty in capturing fine-scale variation in fuel characteristics and fire behaviour. Fire movement between patches of fuel can have implications for modelling fire...

Does geology help in the final disposal of radioactive wastes?

International Nuclear Information System (INIS)

Schaer, U.

1987-01-01

High-level radioactive wastes have to be stored safely for thousands of years in deep geological formations. The question discussed is whether or not a geological prognosis over this span of time is possible. The main problem is groundwater

Organizational heterogeneity of vertebrate genomes.

Science.gov (United States)

Frenkel, Svetlana; Kirzhner, Valery; Korol, Abraham

2012-01-01

Genomes of higher eukaryotes are mosaics of segments with various structural, functional, and evolutionary properties. The availability of whole-genome sequences allows the investigation of their structure as "texts" using different statistical and computational methods. One such method, referred to as Compositional Spectra (CS) analysis, is based on scoring the occurrences of fixed-length oligonucleotides (k-mers) in the target DNA sequence. CS analysis allows generating species- or region-specific characteristics of the genome, regardless of their length and the presence of coding DNA. In this study, we consider the heterogeneity of vertebrate genomes as a joint effect of regional variation in sequence organization superimposed on the differences in nucleotide composition. We estimated compositional and organizational heterogeneity of genome and chromosome sequences separately and found that both heterogeneity types vary widely among genomes as well as among chromosomes in all investigated taxonomic groups. The high correspondence of heterogeneity scores obtained on three genome fractions, coding, repetitive, and the remaining part of the noncoding DNA (the genome dark matter--GDM) allows the assumption that CS-heterogeneity may have functional relevance to genome regulation. Of special interest for such interpretation is the fact that natural GDM sequences display the highest deviation from the corresponding reshuffled sequences.

Organizational heterogeneity of vertebrate genomes.

Directory of Open Access Journals (Sweden)

Svetlana Frenkel

Full Text Available Genomes of higher eukaryotes are mosaics of segments with various structural, functional, and evolutionary properties. The availability of whole-genome sequences allows the investigation of their structure as "texts" using different statistical and computational methods. One such method, referred to as Compositional Spectra (CS analysis, is based on scoring the occurrences of fixed-length oligonucleotides (k-mers in the target DNA sequence. CS analysis allows generating species- or region-specific characteristics of the genome, regardless of their length and the presence of coding DNA. In this study, we consider the heterogeneity of vertebrate genomes as a joint effect of regional variation in sequence organization superimposed on the differences in nucleotide composition. We estimated compositional and organizational heterogeneity of genome and chromosome sequences separately and found that both heterogeneity types vary widely among genomes as well as among chromosomes in all investigated taxonomic groups. The high correspondence of heterogeneity scores obtained on three genome fractions, coding, repetitive, and the remaining part of the noncoding DNA (the genome dark matter--GDM allows the assumption that CS-heterogeneity may have functional relevance to genome regulation. Of special interest for such interpretation is the fact that natural GDM sequences display the highest deviation from the corresponding reshuffled sequences.

Dynamics of spatial heterogeneity of stomatal closure in Tradescantia virginiana altered by growth at high relative air humidity

NARCIS (Netherlands)

Rezaei Nejad, A.; Harbinson, J.; Meeteren, van U.

2006-01-01

The spatial heterogeneity of stomatal closure in response to rapid desiccation of excised well-watered Tradescantia virginiana leaves grown at moderate (55%) or high (90%) relative air humidity (RH) was studied using a chlorophyll fluorescence imaging system under non-photorespiratory conditions.

Deterministic geologic processes and stochastic modeling

International Nuclear Information System (INIS)

Rautman, C.A.; Flint, A.L.

1992-01-01

This paper reports that recent outcrop sampling at Yucca Mountain, Nevada, has produced significant new information regarding the distribution of physical properties at the site of a potential high-level nuclear waste repository. consideration of the spatial variability indicates that her are a number of widespread deterministic geologic features at the site that have important implications for numerical modeling of such performance aspects as ground water flow and radionuclide transport. Because the geologic processes responsible for formation of Yucca Mountain are relatively well understood and operate on a more-or-less regional scale, understanding of these processes can be used in modeling the physical properties and performance of the site. Information reflecting these deterministic geologic processes may be incorporated into the modeling program explicitly using geostatistical concepts such as soft information, or implicitly, through the adoption of a particular approach to modeling

Geologic Map of the Thaumasia Region, Mars

Science.gov (United States)

Dohm, Janes M.; Tanaka, Kenneth L.; Hare, Trent M.

2001-01-01

The geology of the Thaumasia region (fig. 1, sheet 3) includes a wide array of rock materials, depositional and erosional landforms, and tectonic structures. The region is dominated by the Thaumasia plateau, which includes central high lava plains ringed by highly deformed highlands; the plateau may comprise the ancestral center of Tharsis tectonism (Frey, 1979; Plescia and Saunders, 1982). The extensive structural deformation of the map region, which is without parallel on Mars in both complexity and diversity, occurred largely throughout the Noachian and Hesperian periods (Tanaka and Davis, 1988; Scott and Dohm, 1990a). The deformation produced small and large extensional and contractional structures (fig. 2, sheet 3) that resulted from stresses related to the formation of Tharsis (Frey, 1979; Wise and others, 1979; Plescia and Saunders, 1982; Banerdt and others, 1982, 1992; Watters and Maxwell, 1986; Tanaka and Davis, 1988; Francis, 1988; Watters, 1993; Schultz and Tanaka, 1994), from magmatic-driven uplifts, such as at Syria Planum (Tanaka and Davis, 1988; Dohm and others, 1998; Dohm and Tanaka, 1999) and central Valles Marineris (Dohm and others, 1998, Dohm and Tanaka, 1999), and from the Argyre impact (Wilhelms, 1973; Scott and Tanaka, 1986). In addition, volcanic, eolian, and fluvial processes have highly modified older surfaces in the map region. Local volcanic and tectonic activity often accompanied episodes of valley formation. Our mapping depicts and describes the diverse terrains and complex geologic history of this unique ancient tectonic region of Mars. The geologic (sheet 1), paleotectonic (sheet 2), and paleoerosional (sheet 3) maps of the Thaumasia region were compiled on a Viking 1:5,000,000-scale digital photomosaic base. The base is a combination of four quadrangles: the southeast part of Phoenicis Lacus (MC–17), most of the southern half of Coprates (MC–18), a large part of Thaumasia (MC–25), and the northwest margin of Argyre (MC–26

Characterisation of the heterogeneity of karst using electrical geophysics - applications in SW China

Science.gov (United States)

Binley, A. M.; Cheng, Q.; Tao, M.; Chen, X.

2017-12-01

The southwest China karst region is one of the largest globally continuous karst areas. The great (structural, hydrological and geochemical) complexity of karstic environments and their rapidly evolving nature make them extremely vulnerable to natural and anthropogenic processes/activities. Characterising the location and properties of structures within the karst critical zone, and understanding how the landform is evolving is essential for the mitigation and adaption to locally- and globally-driven changes. Because of the specific nature of karst geology and geomorphology in the humid tropics and subtropics, spatial heterogeneity is high, evidenced by specific landforms features. Such heterogeneity leads to a high dynamic variability of hydrological processes in space and time, along with a complex exchange of surface water and groundwater. Investigating karst hydrogeological features is extremely challenging because of the three-dimensional nature of the system. Observations from boreholes can vary significantly over several metres, making conventional aquifer investigative methods limited. Geophysical methods have emerged as potentially powerful tools for hydrogeological investigations. Geophysical surveys can help to obtain more insight into the complex conduit networks and depth of weathering, both of which can provide quantitative information about the hydrological and hydrochemical dynamics of the system, in addition to providing a better understanding of how critical zone structures have been established and how the landscape is evolving. We present here results from recent geophysical field campaigns in SW China. We illustrate the effectiveness of electrical methods for mapping soil infil in epikarst and report results from field-based investigations along hillslope and valley transects. Our results reveal distinct zones of relatively high electrical conductivity to depths of tens of metres, which we attribute to localised increased fracture density. We

Construction of the Geological Model around KURT area based on the surface investigations

International Nuclear Information System (INIS)

Park, Kyung Woo; Koh, Yong Kwon; Kim, Kyung Su; Choi, Jong Won

2009-01-01

To characterize the geological features in the study area for high-level radioactive waste disposal research, KAERI (Korea Atomic Energy Research Institute) has been performing several geological investigations such as geophysical surveys and borehole drillings since 1997. Especially, the KURT (KAERI Underground Research Tunnel) constructed to understand the deep geological environments in 2006. Recently, the deep boreholes, which have 500 m depth inside the left research module of the KURT and 1,000 m depth outside the KURT, were drilled to confirm and validate the results from a geological model. The objective of this research was to investigate hydrogeological conditions using a 3-D geological model around the KURT. The geological analysis from the surface and borehole investigations determined four important geological elements including subsurface weathered zone, low-angled fractures zone, fracture zones and bedrock for the geological model. In addition, the geometries of these elements were also calculated for the three-dimensional model. The results from 3-D geological model in this study will be beneficial to understand hydrogeological environment in the study area as an important part of high-level radioactive waste disposal technology.

Status and development of deep geological repository in Slovak republic from geological point of view

Directory of Open Access Journals (Sweden)

Jozef Franzen

2007-01-01

Full Text Available During the operation of Slovak NPPs, production of approximately 2,300 metric tons of spent fuel expressed as heavy metal (18,654 spent fuel assemblies is expected. In addition, about 5000 metric tons of radioactive waste unfit for near surface repository at Mochovce and destined for a deep geological disposal. The safe and long-term solution of back-end fuel cycle is so highly required.One of the most favorable solutions is Deep Geological Repository (DGR. The site for a DGR, along with repository design and the engineered barrier system must ensure long-term safety of the disposal system.A preliminary set of site-selection criteria for a DGR was proposed in Slovakia, based on worldwide experience and consistent with IAEA recommendations. Main groups of criteria are: 1 geological and tectonic stability of prospective sites; 2 appropriate characteristics of host rock (lithological homogeneity, suitable hydrogeological and geochemical conditions, favourable geotechnical setting, absence of mineral resources, etc.; 3 conflict of interests (natural resources, natural and cultural heritage, protected resources of thermal waters, etc..Based on the previous geological investigations, three distinct areas (five localities were determined as the most prospective sites for construction of a DGR so far. Three of them are built by granitoids rock (Tribeč Mts., Veporske vrchy Mts. and Stolicke vrchy Mts., other consist of sedimentary rock formations (Cerova vrchovina Upland and Rimavska kotlina Basin. Objective for the next investigation stage is to perform more detailed geological characterization of the prospective sites.

Comments on a letter by George D. DeBuchananne (US Geological Survey) regarding the use of salt domes for high-level waste disposal

International Nuclear Information System (INIS)

1984-08-01

The US Geological Survey (USGS) concluded in a letter to the US Department of Energy, dated March 7, 1981, that subsurface geologic conditions in bedded salt are more predictable and less complex than those in domal salt. This predictability is equated with the relative suitability of bedded and domal salt as repository host media. This report comments on the USGS letter. The key points made are as follows: Complexities which may exist in the geologic setting of a salt dome (or other potential host medium) should not a priori preclude the dome from being an acceptable host medium for a high-level waste (HLW) repository. Predictability, as used by the USGS, focused on the spatial extrapolation of information on geologic conditions and should not be confused with predicting the performance of a repository. Notwithstanding the general characteristics of bedded and domal salt, there are salt domes whose individual characteristics should make them as acceptable as potential bedded salt areas for HLW repository sites. Complexities which may occur in the geologic setting of a salt dome can be explored and characterized with sufficient accuracy by available techniques

Numerical Simulations of the Lunar Penetrating Radar and Investigations of the Geological Structures of the Lunar Regolith Layer at the Chang’E 3 Landing Site

Directory of Open Access Journals (Sweden)

Chunyu Ding

2017-01-01

Full Text Available In the process of lunar exploration, and specifically when studying lunar surface structure and thickness, the established lunar regolith model is usually a uniform and ideal structural model, which is not well-suited to describe the real structure of the lunar regolith layer. The present study aims to explain the geological structural information contained in the channel 2 LPR (lunar penetrating radar data. In this paper, the random medium theory and Apollo drilling core data are used to construct a modeling method based on discrete heterogeneous random media, and the simulation data are processed and collected by the electromagnetic numerical method FDTD (finite-difference time domain. When comparing the LPR data with the simulated data, the heterogeneous random medium model is more consistent with the actual distribution of the media in the lunar regolith layer. It is indicated that the interior structure of the lunar regolith layer at the landing site is not a pure lunar regolith medium but rather a regolith-rock mixture, with rocks of different sizes and shapes. Finally, several reasons are given to explain the formation of the geological structures of the lunar regolith layer at the Chang’E 3 landing site, as well as the possible geological stratification structure.

Study of heat diffusion in a granitic geologic formation of high level radioactive wastes

International Nuclear Information System (INIS)

Goldstein, S.; Juignet, N.

1980-06-01

Thermal study of granitic underground storage of vitrified high level radioactive wastes in a regular network of shafts and galleries. The aim is to show influence on temperature rise of the geologic formation of main parameters to define the storage zone and to determine the network dimension in function of the rock properties. Two models were studied allowing a rapid variation of geometrical and physical parameters. A numerical method using finite element method or Green functions were used for calculations. Temperatures are determined either for the whole storage site or a unit cell of the lattice [fr

High-resolution reservoir characterization by seismic inversion with geological constraints

NARCIS (Netherlands)

Tetyukhina, D.

2010-01-01

Fluvio-deltaic sedimentary systems are of great interest for explorationists because they can form prolific hydrocarbon plays. However, they are also among the most complex and heterogeneous ones encountered in the subsurface. Reservoirs in clinoform systems are difficult to characterize because

Cloning of transgenic tobacco BY-2 cells; an efficient method to analyse and reduce high natural heterogeneity of transgene expression.

Science.gov (United States)

Nocarova, Eva; Fischer, Lukas

2009-04-22

Phenotypic characterization of transgenic cell lines, frequently used in plant biology studies, is complicated because transgene expression in individual cells is often heterogeneous and unstable. To identify the sources and to reduce this heterogeneity, we transformed tobacco (Nicotiana tabacum L.) BY-2 cells with a gene encoding green fluorescent protein (GFP) using Agrobacterium tumefaciens, and then introduced a simple cloning procedure to generate cell lines derived from the individual transformed cells. Expression of the transgene was monitored by analysing GFP fluorescence in the cloned lines and also in lines obtained directly after transformation. The majority ( approximately 90%) of suspension culture lines derived from calli that were obtained directly from transformation consisted of cells with various levels of GFP fluorescence. In contrast, nearly 50% of lines generated by cloning cells from the primary heterogeneous suspensions consisted of cells with homogenous GFP fluorescence. The rest of the lines exhibited "permanent heterogeneity" that could not be resolved by cloning. The extent of fluorescence heterogeneity often varied, even among genetically identical clones derived from the primary transformed lines. In contrast, the offspring of subsequent cloning of the cloned lines was uniform, showing GFP fluorescence intensity and heterogeneity that corresponded to the original clone. The results demonstrate that, besides genetic heterogeneity detected in some lines, the primary lines often contained a mixture of epigenetically different cells that could be separated by cloning. This indicates that a single integration event frequently results in various heritable expression patterns, which are probably accidental and become stabilized in the offspring of the primary transformed cells early after the integration event. Because heterogeneity in transgene expression has proven to be a serious problem, it is highly advisable to use transgenes tagged with

Submarine geologic disposal of nuclear waste

International Nuclear Information System (INIS)

Hollister, C.D.; Corliss, B.H.; Anderson, D.R.

1980-01-01

Site suitability characteristics of submarine geological formations for the disposal of radioactive wastes include the distribution coefficient of the host medium, permeability, viscoelastic nature of the sediments, influence of organic material on remobilization, and effects of thermal stress. The submarine geological formation that appears to best satisfy these criteria is abyssal ''red'' clay. Regions in the ocean that have coarse-grained deposits, high or variable thermal conductivity, high organic carbon content, and sediment thickness of less than 50 m are not being considered at this time. The optimum geological environment should be tranquil and have environmental predictability over a minimum of 10 5 years. Site selection activities for the North Atlantic and North Pacific are reviewed and future activities which include international cooperation are discussed. A paleoenvironmental model for Cenozoic sedimentation in the central North Pacific is presented based on studies of a long core from the Mid-Plate Gyre MPG-1 area, and is an example of the type of study that will be carried out in other seabed study areas. The data show that the MPG-1 region has been an area of slow, continuous accumulation during the past 65 million years. (author)

The geological heritage of the Kurkur-Dungul area in southern Egypt

Science.gov (United States)

Sallam, Emad S.; Ponedelnik, Alena A.; Tiess, Günter; Yashalova, Natalia N.; Ruban, Dmitry A.

2018-01-01

The inventory of the geological heritage of Egypt is important for its efficient conservation and usage for the purposes of science, education, and tourism. The field investigations in the Kurkur-Dungul area in southern Egypt have permitted to identify several unique geological features. Their type, rank, relative abundance, and intrinsic diversity, as well as importance of the entire geological heritage of the study area are investigated. Seven geological heritage types are distinguished, namely stratigraphical, sedimentary, palaeogeographical, mineralogical, structural, geomorphological, and economical types. The rank of the features belonging to the listed types ranges from local to global, and the relative abundance and the intrinsic diversity range from low to high. The global rank is established for the sedimentary type, which is determined by the wide distribution of palaeospring tufa deposits. The high relative abundance and intrinsic diversity are established for the geomorphological type. The entire geological heritage of the Kurkur-Dungul area can be employed for diversification of the existing tourism programs offered at the tourist destination of Aswan, as well as for geotourism development. A geopark can be created in the Kurkur-Dungul area for the better exploitation of its geological heritage. The combined development of geological and industrial tourism seems to be possible.

Geological data acquisition for site characterisation at Olkiluoto: a framework for the phase of underground investigations

International Nuclear Information System (INIS)

Milnes, A.G.; Aaltonen, I.; Kemppainen, K.; Mattila, J.; Wikstroem, L.; Front, K.; Kaerki, A.; Gehoer, S.; Paulamaeki, S.; Paananen, M.; Ahokas, T.

2007-05-01

, have already provided a broad basis of experience for detailed site characterisation. In addition to the lithological data acquisition, other areas of geological data acquisition are also treated here in more detail, particularly with respect to classification schemes, parameterization, and qualitative characterisation for increasing geological site understanding. Important areas which are discussed in detail include: systematic characterisation of foliation and related small-scale heterogeneities, according to type, orientation and degree of development, including the assessment of their rock mechanics significance; identification and description of hydrothermal and other rock alteration phenomena; identification and parameterisation of deformation zone intersections, and their classification in terms of the scientifically established Sibson-Scholz fault zone model (brittle, semi-brittle, low-grade ductile and high-grade ductile deformation zone types); detailed consideration of brittle deformation zone architecture, with particular focus on the characterisation of the core and damage zones, and kinematic parameters; classification and parameterisation of individual fractures, as a background for systematic geological studies as well as systematic data acquisition for rock quality estimation (Q-system) and Discrete Fracture Network modelling (orig.)

Capturing spatial heterogeneity of soil organic carbon under changing climate

Science.gov (United States)

Mishra, U.; Fan, Z.; Jastrow, J. D.; Matamala, R.; Vitharana, U.

2015-12-01

The spatial heterogeneity of the land surface affects water, energy, and greenhouse gas exchanges with the atmosphere. Designing observation networks that capture land surface spatial heterogeneity is a critical scientific challenge. Here, we present a geospatial approach to capture the existing spatial heterogeneity of soil organic carbon (SOC) stocks across Alaska, USA. We used the standard deviation of 556 georeferenced SOC profiles previously compiled in Mishra and Riley (2015, Biogeosciences, 12:3993-4004) to calculate the number of observations that would be needed to reliably estimate Alaskan SOC stocks. This analysis indicated that 906 randomly distributed observation sites would be needed to quantify the mean value of SOC stocks across Alaska at a confidence interval of ± 5 kg m-2. We then used soil-forming factors (climate, topography, land cover types, surficial geology) to identify the locations of appropriately distributed observation sites by using the conditioned Latin hypercube sampling approach. Spatial correlation and variogram analyses demonstrated that the spatial structures of soil-forming factors were adequately represented by these 906 sites. Using the spatial correlation length of existing SOC observations, we identified 484 new observation sites would be needed to provide the best estimate of the present status of SOC stocks in Alaska. We then used average decadal projections (2020-2099) of precipitation, temperature, and length of growing season for three representative concentration pathway (RCP 4.5, 6.0, and 8.5) scenarios of the Intergovernmental Panel on Climate Change to investigate whether the location of identified observation sites will shift/change under future climate. Our results showed 12-41 additional observation sites (depending on emission scenarios) will be required to capture the impact of projected climatic conditions by 2100 on the spatial heterogeneity of Alaskan SOC stocks. Our results represent an ideal distribution

Geological heritage of Morocco

International Nuclear Information System (INIS)

Elhadi, H.; Tahiri, A.

2012-01-01

Full text: The soil and subsoil of Morocco are rich in geological phenomena that bear the imprint of a history that goes back in time more than 2000 million years. Very many sites geologically remarkable exposed in accessible outcrops, with good quality remain unknown to the general public and therefore deserve to be vulgarized. It is a memory to acquaint to the present generations but also to preserve for future generations. In total, a rich geological heritage in many ways: Varied landscapes, international stratotypes, various geological structures, varied rocks, mineral associations, a huge procession of fossiles, remnants of oceanic crust (ophiolites) among oldests ones in the world (800my), etc... For this geological heritage, an approach of an overall inventory is needed, both regionally and nationally, taking into account all the skills of the earth sciences. This will put the item on the natural (geological) potentialities as a lever for sustainable regional development. For this, it is necessary to implement a strategy of ''geoconservation'' for the preservation and assessment of the geological heritage.

Robust Synchronization in an E/I Network with Medium Synaptic Delay and High Level of Heterogeneity

International Nuclear Information System (INIS)

Han Fang; Wang Zhi-Jie; Gong Tao; Fan Hong

2015-01-01

It is known that both excitatory and inhibitory neuronal networks can achieve robust synchronization only under certain conditions, such as long synaptic delay or low level of heterogeneity. In this work, robust synchronization can be found in an excitatory/inhibitory (E/I) neuronal network with medium synaptic delay and high level of heterogeneity, which often occurs in real neuronal networks. Two effects of post-synaptic potentials (PSP) to network synchronization are presented, and the synaptic contribution of excitatory and inhibitory neurons to robust synchronization in this E/I network is investigated. It is found that both excitatory and inhibitory neurons may contribute to robust synchronization in E/I networks, especially the excitatory PSP has a more positive effect on synchronization in E/I networks than that in excitatory networks. This may explain the strong robustness of synchronization in E/I neuronal networks. (paper)

Effects of reservoir heterogeneity on scaling of effective mass transfer coefficient for solute transport

Science.gov (United States)

Leung, Juliana Y.; Srinivasan, Sanjay

2016-09-01

Modeling transport process at large scale requires proper scale-up of subsurface heterogeneity and an understanding of its interaction with the underlying transport mechanisms. A technique based on volume averaging is applied to quantitatively assess the scaling characteristics of effective mass transfer coefficient in heterogeneous reservoir models. The effective mass transfer coefficient represents the combined contribution from diffusion and dispersion to the transport of non-reactive solute particles within a fluid phase. Although treatment of transport problems with the volume averaging technique has been published in the past, application to geological systems exhibiting realistic spatial variability remains a challenge. Previously, the authors developed a new procedure where results from a fine-scale numerical flow simulation reflecting the full physics of the transport process albeit over a sub-volume of the reservoir are integrated with the volume averaging technique to provide effective description of transport properties. The procedure is extended such that spatial averaging is performed at the local-heterogeneity scale. In this paper, the transport of a passive (non-reactive) solute is simulated on multiple reservoir models exhibiting different patterns of heterogeneities, and the scaling behavior of effective mass transfer coefficient (Keff) is examined and compared. One such set of models exhibit power-law (fractal) characteristics, and the variability of dispersion and Keff with scale is in good agreement with analytical expressions described in the literature. This work offers an insight into the impacts of heterogeneity on the scaling of effective transport parameters. A key finding is that spatial heterogeneity models with similar univariate and bivariate statistics may exhibit different scaling characteristics because of the influence of higher order statistics. More mixing is observed in the channelized models with higher-order continuity. It

Multiscale Lattice Boltzmann method for flow simulations in highly heterogenous porous media

KAUST Repository

Li, Jun

2013-01-01

A lattice Boltzmann method (LBM) for flow simulations in highly heterogeneous porous media at both pore and Darcy scales is proposed in the paper. In the pore scale simulations, flow of two phases (e.g., oil and gas) or two immiscible fluids (e.g., water and oil) are modeled using cohesive or repulsive forces, respectively. The relative permeability can be computed using pore-scale simulations and seamlessly applied for intermediate and Darcy-scale simulations. A multiscale LBM that can reduce the computational complexity of existing LBM and transfer the information between different scales is implemented. The results of coarse-grid, reduced-order, simulations agree very well with the averaged results obtained using fine grid.

Determining probabilities of geologic events and processes

International Nuclear Information System (INIS)

Hunter, R.L.; Mann, C.J.; Cranwell, R.M.

1985-01-01

The Environmental Protection Agency has recently published a probabilistic standard for releases of high-level radioactive waste from a mined geologic repository. The standard sets limits for contaminant releases with more than one chance in 100 of occurring within 10,000 years, and less strict limits for releases of lower probability. The standard offers no methods for determining probabilities of geologic events and processes, and no consensus exists in the waste-management community on how to do this. Sandia National Laboratories is developing a general method for determining probabilities of a given set of geologic events and processes. In addition, we will develop a repeatable method for dealing with events and processes whose probability cannot be determined. 22 refs., 4 figs

Development of geological disposal system for spent fuels and high-level radioactive wastes in Korea

International Nuclear Information System (INIS)

Choi, Heui Joo; Lee, Jong Youl; Choi, Jong Won

2013-01-01

Two different kinds of nuclear power plants produce a substantial amount of spent fuel annually in Korea. According to the current projection, it is expected that around 60,000 MtU of spent fuel will be produced from 36 PWR and APR reactors and 4 CANDU reactors by the end of 2089. In 2006, KAERI proposed a conceptual design of a geological disposal system (called KRS, Korean Reference disposal System for spent fuel) for PWR and CANDU spent fuel, as a product of a 4-year research project from 2003 to 2006. The major result of the research was that it was feasible to construct a direct disposal system for 20,000 MtU of PWR spent fuels and 16,000 MtU of CANDU spent fuel in the Korean peninsula. Recently, KAERI and MEST launched a project to develop an advanced fuel cycle based on the pyroprocessing of PWR spent fuel to reduce the amount of HLW and reuse the valuable fissile material in PWR spent fuel. Thus, KAERI has developed a geological disposal system for high-level waste from the pyroprocessing of PWR spent fuel since 2007. However, since no decision was made for the CANDU spent fuel, KAERI improved the disposal density of KRS by introducing several improved concepts for the disposal canister. In this paper, the geological disposal systems developed so far are briefly outlined. The amount and characteristics of spent fuel and HLW, 4 kinds of disposal canisters, the characteristics of a buffer with domestic Ca-bentonite, and the results of a thermal design of deposition holes and disposal tunnels are described. The different disposal systems are compared in terms of their disposal density.

Low probability natural phenomena and crustal movement on high level radioactive waste geological disposal

International Nuclear Information System (INIS)

Kusunose, Kinichiro; Sato, Takashi; Cho, Akio; Togashi, Shigeko; Matsumoto, Akikazu; Kanai, Yutaka; Okumura, Koji; Shimokawa, Koichi; Mizuno, Kiyohide

1998-01-01

On subtheme ''development of long-term estimate method of crystal movement'', a control method has been developed under the conditions of 500 MPa confining pressure at 300degC. The method was tested under the conditions of 100 MPa confining pressure at room temperature and the rock fracture experiment was succeeded. On subtheme ''estimation method on the effect of volcanic activity'', in order to evaluate the effects of tephra fall on environment, pollen analysis of sample on outcrop in Sakaida and the topographic and geological survey of river terrace along Nyu-river in Yamagata prefecture were carried out. These results showed number of pollen was decreased immediately after AT tephra fall originated in Kyushu, so that effect of ash on forest was proved. However, the effect of AT tephra fall on ecological system was not so large as changing forest compositing species. On establishment of accurate geologic time measurement of pyroclastic materials, uranium and thorium were chemically separated from various kinds of mineral concentrated materials separated from pyroclastic materials. Iso chron of them was obtained by alpha count. Moreover, a direct geologic time measurement method for distal tephra was developed by pottasium-argon method. It makes possible direct measurement of geological time of young pyroclastic flow sediment. (S.Y.)

Geological Services Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Researchers use computed tomography (CT) scanners at NETL’s Geological Services Laboratory in Morgantown, WV, to peer into geologic core samples to determine how...

Geology of Mars

International Nuclear Information System (INIS)

Soderblom, L.A.

1988-01-01

The geology of Mars and the results of the Mariner 4, 6/7, and 9 missions and the Viking mission are reviewed. The Mars chronology and geologic modification are examined, including chronological models for the inactive planet, the active planet, and crater flux. The importance of surface materials is discussed and a multispectral map of Mars is presented. Suggestions are given for further studies of the geology of Mars using the Viking data. 5 references

[Geognosy versus Geology: National Modes of Thought and Cultural Practices Concerning Space and Time in Competition].

Science.gov (United States)

Klemun, Marianne

2015-09-01

Natural science investigators at the end of the eighteenth century made use of conflicting labels to position their respective preferred fields of activity in the Earth sciences. This mania for labelling marked their break with natural science and the umbrella term 'mineralogy'. In this conflict situation of specialist classifications and explanations, two terms in particular were established: geognosy and geology, which covered the very promising project of research in the areas of the 'origin of the Earth' and the 'formation of the Earth'. These and the associated research goals were subsequently accorded a dazzling career. Proceeding from the conceptual core-meaning in the formation of terms und its semantic spectrum and conceptual shifts in a time of change, my study will look at the identity and heterogeneity functions of geology and geognosy. For whereas in French and English speaking countries the term geology came to be used exclusively (geology, géologie), this was avoided in German, particularly because the term geognosy was preferred. These national differences may be explained with reference to the different cultural and national styles of science: for example the social embedding of geology in the culture of the English gentleman or the French museum culture, and the close connection of 'German' geognosy to mining. A further starting point in the analysis of the double use of both geology and geognosy in German speaking countries until 1840 is provided by the different references to temporalization and spatialization of the two terms. And we should also include the practical implications and the epistemic requirements that were bound up with the defence of geognosy in the German speaking world.

History of geological disposal concept (3). Implementation phase of geological disposal (2000 upward)

International Nuclear Information System (INIS)

Masuda, Sumio; Sakuma, Hideki; Umeki, Hiroyuki

2015-01-01

Important standards and concept about geological disposal have been arranged as an international common base and are being generalized. The authors overview the concept of geological disposal, and would like this paper to help arouse broad discussions for promoting the implementation plan of geological disposal projects in the future. In recent years, the scientific and technological rationality of geological disposal has been recognized internationally. With the addition of discussions from social viewpoints such as ethics, economy, etc., geological disposal projects are in the stage of starting after establishment of social consensus. As an international common base, the following consolidated and systematized items have been presented as indispensable elements in promoting business projects: (1) step-by-step approach, (2) safety case, (3) reversibility and recovery potential, and (4) trust building and communications. This paper outlines the contents of the following cases, where international common base was reflected on the geological disposal projects in Japan: (1) final disposal method and safety regulations, and (2) impact of the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Station accident on geological disposal plan. (A.O.)

Conduct of Geologic Field Work During Planetary Exploration: Why Geology Matters

Science.gov (United States)

Eppler, Dean B.

2010-01-01

The science of field geology is the investigative process of determining the distribution of rock units and structures on a planet fs surface, and it is the first-order data set that informs all subsequent studies of a planet, such as geochemistry, geochronology, geophysics, or remote sensing. For future missions to the Moon and Mars, the surface systems deployed must support the conduct of field geology if these endeavors are to be scientifically useful. This lecture discussed what field geology is all about.why it is important, how it is done, how conducting field geology informs many other sciences, and how it affects the design of surface systems and the implementation of operations in the future.

Geology's Impact on Culture

Science.gov (United States)

Pizzorusso, Ann

2017-04-01

Most people consider geology boring, static and difficult. The fields of astronomy and physics have "rebranded" themselves with exciting programs formatted so as to be readily understandable to the general public. The same thing can be done for geology. My research on geology's influence on other disciplines has resulted in a book, Tweeting da Vinci, in which I was able to show how geology affected Italy's art, architecture, medicine, religion, literature, engineering and just about everything else. The reaction to the book and my lectures by both students and the general public has been very positive, including four gold medals, with reviews and comments indicating that they never knew geology could be so exciting. The book is very user friendly, packed with facts, full-color photos, paintings, sketches and illustrations. Complex aspects of geology are presented in an easily understandable style. Widely diverse topics—such as gemology, folk remedies, grottoes, painting, literature, physics and religion—are stitched together using geology as a thread. Quoting everyone from Pliny the Elder to NASA physicist Friedemann Freund, the work is solidly backed scholarship that reads as easily as a summer novel. The book can be used in classes such as physics, chemistry, literature, art history, medicine, Classical Studies, Latin, Greek and Italian. By incorporating a "geologic perspective" in these courses, it can be perceived as a more "all encompassing" discipline and encourage more students to study it. The lectures I have given on college campuses have resulted in students seeing their own majors from a different perspective and some have even signed up for introductory geology courses. One college organized summer course to the Bay of Naples based on the book. We followed the geology as well as the culture of the area and the students were profoundly moved. To encourage dialog, the book is linked to Facebook, Twitter and Instagram. This has enabled followers from

Development of grouting technologies for geological disposal of high level waste in Japan (1). Overall program and application of developed technologies

International Nuclear Information System (INIS)

Fujita, Tomoo; Sasamoto, Hiroshi; Sugita, Yutaka; Matsui, Hiroya

2013-01-01

The Japan Atomic Energy Agency started a grout project for geological disposal of high-level radioactive waste (HLW) in 2007. The aim of the project was to develop new grouting technologies and grout materials and also to develop models for performance assessments, prediction of the long-term radionuclide migration and identify detrimental changes in the host rock by the grout material leachate. This study presents the overall program and the application of key engineering technologies to the construction and operation of an underground facility for the geological disposal of HLW, with particular emphasis on the long-term effects of grout materials. (author)

Environmental geology and hydrology

Science.gov (United States)

Nakić, Zoran; Mileusnić, Marta; Pavlić, Krešimir; Kovač, Zoran

2017-10-01

Environmental geology is scientific discipline dealing with the interactions between humans and the geologic environment. Many natural hazards, which have great impact on humans and their environment, are caused by geological settings. On the other hand, human activities have great impact on the physical environment, especially in the last decades due to dramatic human population growth. Natural disasters often hit densely populated areas causing tremendous death toll and material damage. Demand for resources enhanced remarkably, as well as waste production. Exploitation of mineral resources deteriorate huge areas of land, produce enormous mine waste and pollute soil, water and air. Environmental geology is a broad discipline and only selected themes will be presented in the following subchapters: (1) floods as natural hazard, (2) water as geological resource and (3) the mining and mineral processing as types of human activities dealing with geological materials that affect the environment and human health.

Geologic map of Big Bend National Park, Texas

Science.gov (United States)

Turner, Kenzie J.; Berry, Margaret E.; Page, William R.; Lehman, Thomas M.; Bohannon, Robert G.; Scott, Robert B.; Miggins, Daniel P.; Budahn, James R.; Cooper, Roger W.; Drenth, Benjamin J.; Anderson, Eric D.; Williams, Van S.

2011-01-01

The purpose of this map is to provide the National Park Service and the public with an updated digital geologic map of Big Bend National Park (BBNP). The geologic map report of Maxwell and others (1967) provides a fully comprehensive account of the important volcanic, structural, geomorphological, and paleontological features that define BBNP. However, the map is on a geographically distorted planimetric base and lacks topography, which has caused difficulty in conducting GIS-based data analyses and georeferencing the many geologic features investigated and depicted on the map. In addition, the map is outdated, excluding significant data from numerous studies that have been carried out since its publication more than 40 years ago. This report includes a modern digital geologic map that can be utilized with standard GIS applications to aid BBNP researchers in geologic data analysis, natural resource and ecosystem management, monitoring, assessment, inventory activities, and educational and recreational uses. The digital map incorporates new data, many revisions, and greater detail than the original map. Although some geologic issues remain unresolved for BBNP, the updated map serves as a foundation for addressing those issues. Funding for the Big Bend National Park geologic map was provided by the United States Geological Survey (USGS) National Cooperative Geologic Mapping Program and the National Park Service. The Big Bend mapping project was administered by staff in the USGS Geology and Environmental Change Science Center, Denver, Colo. Members of the USGS Mineral and Environmental Resources Science Center completed investigations in parallel with the geologic mapping project. Results of these investigations addressed some significant current issues in BBNP and the U.S.-Mexico border region, including contaminants and human health, ecosystems, and water resources. Funding for the high-resolution aeromagnetic survey in BBNP, and associated data analyses and

Geologic Time.

Science.gov (United States)

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.…

Geological field study for science education on Elementary and Junior high school student, in Shimane prefecture, Japan

Science.gov (United States)

Matsumoto, I.

2011-12-01

The importance of learning at field has been increasing in the elementary and the junior high school in Japan. And, an environmental education is one of the important subjects even in the school education, too. It was important, as for science education, understanding with actual feeling and learning were specified as for the Teaching outlines (the Japanese Ministry of Education, Culture, Sports, Science and Technology) of the new science textbook of the elementary and the junior high school as well. However, It is a little actual situation that there is in an opportunity for the field learning enforced in the school lesson by the investigation of JST (Japan Science and Tecnology Agency). This tendency is strong as much as school of the city and that circumference. I have this cause think that there are a few suitable places for learning to observe geological and biological field near school. In addition, below two is pointed out as a big problem to obstruct the execution of field learning. 1) A natural experience isn't being done sufficient as much as a teacher can teach to the student. 2) It doesn't have the confidence that a teacher teaches a student geology and biology at the field. I introduce the practical example of geological field learning at the public elementary school of the Shimane prefecture by this research. Though it is the place where nature is comparatively rich even in Japan, it can't be said that field learning is popular in Shimane prefecture. A school teacher has to learning experience at field, and he must settle confidence to guide a student at the field. A specialist in the university and the museum must support continuous learning for that to the school teacher.

High Content Analysis of Compositional Heterogeneities to Study GPCR Oligomerization

DEFF Research Database (Denmark)

Walsh, Samuel McEwen

In this thesis I demonstrate how the natural compositional heterogeneities of synthetic and living cell model systems can be used to quantitate the mechanics of G-protein coupled receptor (GPCR) oligomerization with Förster resonance energy transfer (FRET). The thesis is structured around three a...

Japanese issues on the future behavior of the geological environment

International Nuclear Information System (INIS)

Aoki, Kaz; Nakatsuka, Noboru; Ishimaru, Tsuneari

1994-01-01

Comprehending and predicting the future states of the geological environment is very important in ensuring a safe geological disposal of high level radioactive wastes (HLW). This paper is one in a series of studies required to ascertain the existence of a geologically stable area in Japan over the long term. In particular, interest is focussed on the aspect of accumulating data on behavior patterns of selected natural phenomena which will enable predictions of future behavior of geological processes and finding of areas of long term stability. While this paper limits itself to the second and part of the third step, the overall flow-chart of study on natural processes and events which may perturb the geological environment entails three major steps. They include: (i) identification of natural processes and events relevant to long term stability of geological environment to be evaluated; (ii) characterization of the identified natural processes and events; and (iii) prediction of the probability of occurrence, magnitude and influence of the natural processes and events which may perturb the geological environment. (J.P.N)

Overview of medium heterogeneity and transport processes

International Nuclear Information System (INIS)

Tsang, Y.; Tsang, C.F.

1993-11-01

Medium heterogeneity can have significant impact on the behavior of solute transport. Tracer breakthrough curves from transport in a heterogeneous medium are distinctly different from that in a homogeneous porous medium. Usually the shape of the breakthrough curves are highly non-symmetrical with a fast rise at early times and very long tail at late times, and often, they consist of multiple peaks. Moreover, unlike transport in a homogeneous medium where the same transport parameters describe the entire medium, transport through heterogeneous media gives rise to breakthrough curves which have strong spatial dependence. These inherent characteristics of transport in heterogeneous medium present special challenge to the performance assessment of a potential high level nuclear waste repository with respect to the possible release of radio nuclides to the accessible environment. Since an inherently desirable site characteristic for a waste repository is that flow and transport should be slow, then transport measurements in site characterization efforts will necessarily be spatially small and temporally short compare to the scales which are of relevance to performance assessment predictions. In this paper we discuss the role of medium heterogeneity in site characterization and performance assessment. Our discussion will be based on a specific example of a 3D heterogeneous stochastic model of a site generally similar to, the Aespoe Island, the site of the Hard Rock Laboratory in Southern Sweden. For our study, alternative 3D stochastic fields of hydraulic conductivities conditioned on ''point'' measurements shall be generated. Results of stochastic flow and transport simulations would be used to address the issues of (1) the relationship of tracer breakthrough with the structure of heterogeneity, and (2) the inference from small scale testing results to large scale and long term predictions

State-of-the-art in Heterogeneous Computing

Directory of Open Access Journals (Sweden)

Andre R. Brodtkorb

2010-01-01

Full Text Available Node level heterogeneous architectures have become attractive during the last decade for several reasons: compared to traditional symmetric CPUs, they offer high peak performance and are energy and/or cost efficient. With the increase of fine-grained parallelism in high-performance computing, as well as the introduction of parallelism in workstations, there is an acute need for a good overview and understanding of these architectures. We give an overview of the state-of-the-art in heterogeneous computing, focusing on three commonly found architectures: the Cell Broadband Engine Architecture, graphics processing units (GPUs, and field programmable gate arrays (FPGAs. We present a review of hardware, available software tools, and an overview of state-of-the-art techniques and algorithms. Furthermore, we present a qualitative and quantitative comparison of the architectures, and give our view on the future of heterogeneous computing.

The French geological disposal project CIGEO

Energy Technology Data Exchange (ETDEWEB)

Ouzounian, G. [ANDRA, Chatenay-Malabry cedex (France)

2015-07-01

This paper discusses the major management options for high level waste in France. Safety of the population and protection of the environment is the first priority. Reprocessing of used fuel and reuse of valuable material is considered. Reversible geological disposal (Cigéo Project) is the reference solution for the high-level waste.

Geological disposal of nuclear waste

International Nuclear Information System (INIS)

1979-01-01

Fourteen papers dealing with disposal of high-level radioactive wastes are presented. These cover disposal in salt deposits, geologic deposits and marine disposal. Also included are papers on nuclear waste characterization, transport, waste processing technology, and safety analysis. All of these papers have been abstracted and indexed

Use of high-resolution satellite images for detection of geological structures related to Calerias geothermal field, Chile

Science.gov (United States)

Arellano-Baeza, A. A.; Urzua, L.

2011-12-01

Chile has enormous potential to use the geothermal resources for electric energy generation. The main geothermal fields are located in the Central Andean Volcanic Chain in the North, between the Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the LANDSAT and ASTER satellites have been used to delineate the geological structures related to the Calerias geothermal field located at the northern end of the Southern Volcanic Zone of Chile. It was done by applying the lineament extraction technique developed by authors. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament density increases in the areas of the major heat flux indicating that the lineament analysis could be a power tool for the detection of faults and joint zones associated to the geothermal fields.

Geologic mapping of Kentucky; a history and evaluation of the Kentucky Geological Survey--U.S. Geological Survey Mapping Program, 1960-1978

Science.gov (United States)

Cressman, Earle Rupert; Noger, Martin C.

1981-01-01

In 1960, the U.S. Geological Survey and the Kentucky Geological Survey began a program to map the State geologically at a scale of 1:24,000 and to publish the maps as 707 U.S. Geological Survey Geologic Quadrangle Maps. Fieldwork was completed by the spring of 1977, and all maps were published by December 1978. Geologic mapping of the State was proposed by the Kentucky Society of Professional Engineers in 1959. Wallace W. Hagan, Director and State Geologist of the Kentucky Geological Survey, and Preston McGrain, Assistant State Geologist, promoted support for the proposal among organizations such as Chambers of Commerce, industrial associations, professional societies, and among members of the State government. It was also arranged for the U.S. Geological Survey to supply mapping personnel and to publish the maps; the cost would be shared equally by the two organizations. Members of the U.S. Geological Survey assigned to the program were organized as the Branch of Kentucky Geology. Branch headquarters, including an editorial staff, was at Lexington, Ky., but actual mapping was conducted from 18 field offices distributed throughout the State. The Publications Division of the U.S. Geological Survey established a cartographic office at Lexington to prepare the maps for publication. About 260 people, including more than 200 professionals, were assigned to the Branch of Kentucky Geology by the U.S. Geological Survey at one time or another. The most geologists assigned any one year was 61. To complete the mapping and ancillary studies, 661 professional man-years were required, compared with an original estimate of 600 man-years. A wide variety of field methods were used, but most geologists relied on the surveying altimeter to obtain elevations. Surface data were supplemented by drill-hole records, and several dozen shallow diamond-drill holes were drilled to aid the mapping. Geologists generally scribed their own maps, with a consequent saving of publication costs

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

Science.gov (United States)

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.

Radioactive waste disposal in geological formations

International Nuclear Information System (INIS)

Gera, F.

1977-01-01

The nuclear energy controversy, now raging in several countries, is based on two main issues: the safety of nuclear plants and the possibility to dispose safely of the long-lived radioactive wastes. Consideration of the evolution of the hazard potential of waste in function of decay time leads to a somewhat conservative reference containment time in the order of one hundred thousand years. Several concepts have been proposed for the disposal of long-lived wastes. At the present time, emplacement into suitable geological formations under land areas can be considered the most promising disposal option. It is practically impossible to define detailed criteria to be followed in selecting suitable sites for disposal of long-lived wastes. Basically there is a single criterion, namely; that the geological environment must be able to contain the wastes for at least a hundred thousand years. However, due to the extreme variability of geological settings, it is conceivable that this basic capability could be provided by a great variety of different conditions. The predominant natural mechanism by which waste radionuclides could be moved from a sealed repository in a deep geological formation into the biosphere is leaching and transfer by ground water. Hence the greatest challenge is to give a satisfactory demonstration that isolation from ground water will persist over the required containment time. Since geological predictions are necessarily affected by fairly high levels of uncertainty, the only practical approach is not a straight-forward forecast of future geological events, but a careful assessment of the upper limits of geologic changes that could take place in the repository area over the next hundred thousand years. If waste containment were to survive these extreme geological changes the disposal site could be considered acceptable. If some release of activity were to take place in consequence of the hypothetical events the disposal solution might still be

New tools, technology and techniques applied in geological sciences: current situation and future perspectives

International Nuclear Information System (INIS)

Ulloa, Andres

2014-01-01

Technological tools and work methodologies most used in the area of geological sciences are reviewed and described. The various electronic devices such as laptops, palmtops or PDA (personal digital assistant), tablets and smartphones have allowed to take field geological data and store them efficiently. Tablets and smartphones have been convenient for data collection of scientific data by the diversity of sensors that present, portability, autonomy and the possibility to install specific applications. High precision GPS in conjunction with LIDAR technology and sonar technology have been more accessible and used for geological research, generating high resolution three-dimensional models to complement geological studies. Remote sensing techniques such as high penetration radar are used to perform models of the ice thickness and topography in Antarctic. Modern three-dimensional scanning and printing techniques are used in geological science research and teaching. Currently, the advance in the computer technology has allowed to handle three-dimensional models on personal computers efficiently way and with different display options. Some, of the new areas of geology, emerged recently, are mentioned to generate a broad panorama toward where can direct geological researches in the next years [es

Development of JNC geological disposal technical information integration system for geological environment field

International Nuclear Information System (INIS)

Tsuchiya, Makoto; Ueta, Shinzo; Ohashi, Toyo

2004-02-01

Enormous data on geology, geological structure, hydrology, geochemistry and rock properties should be obtained by various investigation/study in the geological disposal study. Therefore, 'JNC Geological Disposal Technical Information Integration System for Geological Environment Field' was developed in order to manage these data systematically and to support/promote the use of these data for the investigators concerned. The system is equipped with data base to store the information of the works and the background information of the assumptions built up in the works on each stage of data flow ('instigative', → 'data sampling' → interpretation' → conceptualization/modeling/simulation' → 'output') in the geological disposal study. In this system the data flow is shown as 'plan' composed of task' and 'work' to be done in the geological disposal study. It is possible to input the data to the database and to refer data from the database by using GUI that shows the data flow as 'plan'. The system was installed to the server computer possessed by JNC and the system utilities were checked on both the server computer and client computer also possessed by JNC. (author)

Geologic Resource Evaluation of Pu'ukohola Heiau National Historic Site, Hawai'i: Part I, Geology and Coastal Landforms

Science.gov (United States)

Richmond, Bruce M.; Cochran, Susan A.; Gibbs, Ann E.

2008-01-01

Geologic resource inventories of lands managed by the National Park Service (NPS) are important products for the parks and are designed to provide scientific information to better manage park resources. Park-specific geologic reports are used to identify geologic features and processes that are relevant to park ecosystems, evaluate the impact of human activities on geologic features and processes, identify geologic research and monitoring needs, and enhance opportunities for education and interpretation. These geologic reports are planned to provide a brief geologic history of the park and address specific geologic issues forming a link between the park geology and the resource manager. The Kona coast National Parks of the Island of Hawai'i are intended to preserve the natural beauty of the Kona coast and protect significant ancient structures and artifacts of the native Hawaiians. Pu'ukohola Heiau National Historic Site (PUHE), Kaloko-Honokohau National Historical Park (KAHO), and Pu'uhonua O Honaunau National Historical Park (PUHO) are three Kona parks studied by the U.S. Geological Survey (USGS) Coastal and Marine Geology Team in cooperation with the National Park Service. This report is one of six related reports designed to provide geologic and benthic-habitat information for the three Kona parks. Each geology and coastal-landform report describes the regional geologic setting of the Hawaiian Islands, gives a general description of the geology of the Kona coast, and presents the geologic setting and issues for one of the parks. The related benthic-habitat mapping reports discuss the marine data and habitat classification scheme, and present results of the mapping program. Pu'ukohola Heiau National Historic Site (PUHE) is the smallest (~86 acres) of three National Parks located on the leeward Kona coast of the Island of Hawai'i. The main structure at PUHE, Pu'ukohola Heiau, is an important historical temple that was built during 1790-91 by King Kamehameha I

Role of waste packages in the safety of a high level waste repository in a deep geological formation

International Nuclear Information System (INIS)

Bretheau, F.; Lewi, J.

1990-06-01

The safety of a radioactive waste disposal facility lays on the three following barriers placed between the radioactive materials and the biosphere: the waste package; the engineered barriers; the geological barrier. The function assigned to each of these barriers in the performance assessment is an option taken by the organization responsible for waste disposal management (ANDRA in France), which must show that: expected performances of each barrier (confinement ability, life-time, etc.) are at least equal to those required to fulfill the assigned function; radiation protection requirements are met in all situations considered as credible, whether they be the normal situation or random event situations. The French waste management strategy is based upon two types of disposal depending on the nature and activity of waste packages: - surface disposal intended for low and medium level wastes having half-lives of about 30 years or less and alpha activity less than 3.7 MBq/kg (0.1 Ci/t), for individual packages and less than 0.37 MBq/kg (0.01 Ci/t) in the average. Deep geological disposal intended for TRU and high level wastes. The conditions of acceptance of packages in a surface disposal site are subject to the two fundamental safety rules no. I.2 and III.2.e. The present paper is only dealing with deep geological disposal. For deep geological repositories, three stages are involved: stage preceding definitive disposal (intermediate storage, transportation, handling, setting up in the disposal cavities); stage subsequent to definitive sealing of the disposal cavities but prior to the end of operation of the repository; stage subsequent to closure of the repository. The role of the geological barrier has been determined as the essential part of long term radioactivity confinement, by a working group, set up by the French safety authorities. Essential technical criteria relating to the choice of a site so defined by this group, are the following: very low permeability

Regional and site geological frameworks : proposed Deep Geologic Repository, Bruce County, Ontario

Energy Technology Data Exchange (ETDEWEB)

Raven, K.; Sterling, S.; Gaines, S.; Wigston, A. [Intera Engineering Ltd., Ottawa, ON (Canada); Frizzell, R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

2009-07-01

The Nuclear Waste Management Organization is conducting geoscientific studies on behalf of Ontario Power Generation into the proposed development of a Deep Geologic Repository (DGR) for low and intermediate level radioactive waste (L and ILW) at the Bruce site, near Tiverton, Ontario. This paper presented a regional geological framework for the site that was based on a review of regional drilling; structural geology; paleozoic stratigraphy and sedimentology; a 3D geological framework model; a DGR geological site characterization model; bedrock stratigraphy and marker beds; natural fracture frequency data; and formation predictability. The studies have shown that the depth, thickness, orientation and rock quality of the 34 rock formations, members or units that comprise the 840 m thick Paleozoic bedrock sequence at the Bruce site are very uniform and predictable over distances of several kilometres. The proposed DGR will be constructed as an engineered facility comprising a series of underground emplacement rooms at a depth of 680 metres below ground within argillaceous limestones. The geoscientific studies are meant to provide a basis for the development of descriptive geological, hydrogeological and geomechanical models of the DGR site that will facilitate environmental and safety assessments. 11 refs., 3 tabs., 9 figs.

DEVELOPMENT OF GEOLOGICAL DISPOSAL SYSTEMS FOR SPENT FUELS AND HIGH-LEVEL RADIOACTIVE WASTES IN KOREA

Directory of Open Access Journals (Sweden)

HEUI-JOO CHOI

2013-02-01

Full Text Available Two different kinds of nuclear power plants produce a substantial amount of spent fuel annually in Korea. According to the current projection, it is expected that around 60,000 MtU of spent fuel will be produced from 36 PWR and APR reactors and 4 CANDU reactors by the end of 2089. In 2006, KAERI proposed a conceptual design of a geological disposal system (called KRS, Korean Reference disposal System for spent fuel for PWR and CANDU spent fuel, as a product of a 4-year research project from 2003 to 2006. The major result of the research was that it was feasible to construct a direct disposal system for 20,000 MtU of PWR spent fuels and 16,000 MtU of CANDU spent fuel in the Korean peninsula. Recently, KAERI and MEST launched a project to develop an advanced fuel cycle based on the pyroprocessing of PWR spent fuel to reduce the amount of HLW and reuse the valuable fissile material in PWR spent fuel. Thus, KAERI has developed a geological disposal system for high-level waste from the pyroprocessing of PWR spent fuel since 2007. However, since no decision was made for the CANDU spent fuel, KAERI improved the disposal density of KRS by introducing several improved concepts for the disposal canister. In this paper, the geological disposal systems developed so far are briefly outlined. The amount and characteristics of spent fuel and HLW, 4 kinds of disposal canisters, the characteristics of a buffer with domestic Ca-bentonite, and the results of a thermal design of deposition holes and disposal tunnels are described. The different disposal systems are compared in terms of their disposal density.

Japan's Siting Process for the Geological Disposal of High-level Radioactive Waste - An International Peer Review

International Nuclear Information System (INIS)

Brassinnes, Stephane; Fabbri, Olivier; Rubenstone, James; Seppaelae, Timo; Siemann, Michael; ); Kwong, Gloria; )

2016-01-01

The Nuclear Energy Agency carried out an independent peer review of Japan's siting process and criteria for the geological disposal of high-level radioactive waste in May 2016. The review concluded that Japan's site screening process is generally in accordance with international practices. As the goal of the siting process is to locate a site - that is both appropriate and accepted by the community - to host a geological disposal facility for high-level radioactive waste, the international review team emphasises in this report the importance of maintaining an open dialogue and interaction between the regulator, the implementer and the public. Dialogue should begin in the early phases and continue throughout the siting process. The international review team also underlines the importance of taking into account feasibility aspects when selecting a site for preliminary investigations, but suggests that it would be inappropriate to set detailed scientific criteria for nationwide screening at this stage. The team has provided extensive advisory remarks in the report as opportunities for improvement, including the recommendation to use clear and consistent terminology in defining the site screening criteria as it is a critical factor in a successful siting process. (authors)

Titanium Dioxide as a Catalyst Support in Heterogeneous Catalysis

Science.gov (United States)

Bagheri, Samira; Muhd Julkapli, Nurhidayatullaili; Bee Abd Hamid, Sharifah

2014-01-01

The lack of stability is a challenge for most heterogeneous catalysts. During operations, the agglomeration of particles may block the active sites of the catalyst, which is believed to contribute to its instability. Recently, titanium oxide (TiO2) was introduced as an alternative support material for heterogeneous catalyst due to the effect of its high surface area stabilizing the catalysts in its mesoporous structure. TiO2 supported metal catalysts have attracted interest due to TiO2 nanoparticles high activity for various reduction and oxidation reactions at low pressures and temperatures. Furthermore, TiO2 was found to be a good metal oxide catalyst support due to the strong metal support interaction, chemical stability, and acid-base property. The aforementioned properties make heterogeneous TiO2 supported catalysts show a high potential in photocatalyst-related applications, electrodes for wet solar cells, synthesis of fine chemicals, and others. This review focuses on TiO2 as a support material for heterogeneous catalysts and its potential applications. PMID:25383380

AEGIS geologic simulation model

International Nuclear Information System (INIS)

Foley, M.G.

1982-01-01

The Geologic Simulation Model (GSM) is used by the AEGIS (Assessment of Effectiveness of Geologic Isolation Systems) program at the Pacific Northwest Laboratory to simulate the dynamic geology and hydrology of a geologic nuclear waste repository site over a million-year period following repository closure. The GSM helps to organize geologic/hydrologic data; to focus attention on active natural processes by requiring their simulation; and, through interactive simulation and calibration, to reduce subjective evaluations of the geologic system. During each computer run, the GSM produces a million-year geologic history that is possible for the region and the repository site. In addition, the GSM records in permanent history files everything that occurred during that time span. Statistical analyses of data in the history files of several hundred simulations are used to classify typical evolutionary paths, to establish the probabilities associated with deviations from the typical paths, and to determine which types of perturbations of the geologic/hydrologic system, if any, are most likely to occur. These simulations will be evaluated by geologists familiar with the repository region to determine validity of the results. Perturbed systems that are determined to be the most realistic, within whatever probability limits are established, will be used for the analyses that involve radionuclide transport and dose models. The GSM is designed to be continuously refined and updated. Simulation models are site specific, and, although the submodels may have limited general applicability, the input data equirements necessitate detailed characterization of each site before application

Geologic influence on indoor radon concentrations and gamma radiation levels in Norwegian dwellings

Energy Technology Data Exchange (ETDEWEB)

Sundal, Aud Venche

2003-09-01

Indoor radon levels in 1618 Norwegian dwellings located in different geological settings were compared with geological information in order to determine potential correlations between geological factors and indoor radon concentrations in Norway and to establish whether geological information is useful in radon risk analysis. In two geographically limited areas, Kinsarvik and Fen, detailed geological and geochemical investigations were carried out in order to explain their elevated natural radiation environment. Significant correlations between geology and indoor radon concentrations in Norway are found when the properties of both the bedrock and the overburden are taken into account. Areas of high radon risk in Norway include 1) exposed bedrock with elevated levels of radium (mainly alum shale and granites) and b) highly permeable unconsolidated sediments derived from all rock types (mainly glaciofluvial and fluvial deposits) and moderately permeable sediments containing radium rich rock fragments (mainly basal till). More than 20 % of Norwegian dwellings located in the high-risk areas can be expected to contain radon levels exceeding 200 Bq/m3. The elevated radon risk related to penneable building grounds is illustrated in Kinsarvik where the highly permeable sediments and the large vadose zone underlying the Huse residential area enable the transport of radon from large volumes into the dwellings resulting in enhanced indoor radon concentrations. Subterranean air flows caused by temperature/pressure differences between soil air and atmospheric air and elevations differences within the Huse area are shown to strongly affect the annual variations in indoor radon concentrations. The marked contrasts in radon risk potential between different types of building grounds are clearly illustrated in the Fen area where outcrops of the radium rich Fen carbonatites represent areas of high radon risk while only low levels of both indoor radon concentrations and indoor gamma

A new method for the homogeneous precipitative separation of trace level lanthanides as oxalates: application to different types of geological samples

International Nuclear Information System (INIS)

Premadas, A.; Cyriac, Bincy; Kesavan, V.S.

2013-01-01

Oxalate precipitation of lanthanides in acidic medium is a widely used selective group separation method at percentage to trace level in different types of geological samples. Most of the procedures are based on the heterogeneous oxalate precipitation of lanthanides using calcium as carrier. In the heterogeneous precipitation, the co-precipitated impurities from the matrix elements are more, besides if the pH at the time of precipitation is not monitored carefully there is a chance of losing some of the lanthanides. In this report, we present a new homogeneous oxalate precipitation of trace level lanthanides from different types of geological samples using calcium as carrier. In the present method pH is getting adjusted (pH ∼1) on its own, after the hydrolysis of urea added to the sample solution. This acidic pH is essential for the complete precipitation of the lanthanides. Therefore, no critical parameter adjustment for the precipitation is involved in the proposed method. The oxalate precipitate obtained was in crystalline nature which facilitates the fast settlement, easy filtration; besides the co-precipitated matrix elements are very less as compared to normal heterogeneous oxalate precipitation of lanthanides. Another advantage is more quantity of the sample can be taken for the separation of lanthanides which is a limitation for other separation methods reported. Accuracy of the method was checked by analyzing nine international reference materials comprising different types of geological samples obtained from Canadian Certified Reference Project Materials such as syenite samples SY-2, SY-3 and SY-4; gabro sample MRG-1; soil samples SO-1 and SO-2; iron formation sample FeR-2; lake sediments LKSD-2 and LKSD-4. The values of the lanthanides obtained for these reference materials are comparable with recommended values, indicating that the method is accurate. The reproducibility is characterized by a relative standard deviation (RSD) of 1 to 6% (n=4). (author)

JAEA thermodynamic database for performance assessment of geological disposal of high-level and TRU wastes. Refinement of thermodynamic data for trivalent actinoids and samarium

International Nuclear Information System (INIS)

Kitamura, Akira; Fujiwara, Kenso; Yui, Mikazu

2010-01-01

Within the scope of the JAEA thermodynamic database project for performance assessment of geological disposal of high-level radioactive and TRU wastes, the refinement of the thermodynamic data for the inorganic compounds and complexes of trivalent actinoids (actinium(III), plutonium(III), americium(III) and curium(III)) and samarium(III) was carried out. Refinement of thermodynamic data for these elements was based on the thermodynamic database for americium published by the Nuclear Energy Agency in the Organisation for Economic Co-operation and Development (OECD/NEA). Based on the similarity of chemical properties among trivalent actinoids and samarium, complementary thermodynamic data for their species expected under the geological disposal conditions were selected to complete the thermodynamic data set for the performance assessment of geological disposal of radioactive wastes. (author)

Geological status of NWTS repository siting activities in the paradox basin

International Nuclear Information System (INIS)

Frazier, N.A.; Conwell, F.R.

1981-01-01

Emplacement of waste packages in mined geological repositories is one method being evaluated for isolating high-level nuclear wastes. Granite, dome salt, tuff, basalt and bedded salt are among the rock types being investigated. Described in this paper is the status of geological activities in the Paradox Basin of Utah and Colorado, one region being explored as a part of the National Waste Terminal Storage (NWTS) program to site a geological repository in bedded salt

Solving radiative transfer problems in highly heterogeneous media via domain decomposition and convergence acceleration techniques

International Nuclear Information System (INIS)

Previti, Alberto; Furfaro, Roberto; Picca, Paolo; Ganapol, Barry D.; Mostacci, Domiziano

2011-01-01

This paper deals with finding accurate solutions for photon transport problems in highly heterogeneous media fastly, efficiently and with modest memory resources. We propose an extended version of the analytical discrete ordinates method, coupled with domain decomposition-derived algorithms and non-linear convergence acceleration techniques. Numerical performances are evaluated using a challenging case study available in the literature. A study of accuracy versus computational time and memory requirements is reported for transport calculations that are relevant for remote sensing applications.

Crustal structure under the central High Atlas Mountains (Morocco) from geological and gravity data

Science.gov (United States)

Ayarza, P.; Alvarez-Lobato, F.; Teixell, A.; Arboleya, M. L.; Tesón, E.; Julivert, M.; Charroud, M.

2005-05-01

Seismic wide angle and receiver function results together with geological data have been used as constraints to build a gravity-based crustal model of the central High Atlas of Morocco. Integration of a newly acquired set of gravity values with public data allowed us to undertake 2-2.5D gravity modelling along two profiles that cross the entire mountain chain. Modelling suggests moderate crustal thickening, and a general state of Airy isostatic undercompensation. Localized thickening appears restricted to the vicinity of a north-dipping crustal-scale thrust fault, that offsets the Moho discontinuity and defines a small crustal root which accounts for the minimum Bouguer gravity anomaly values. Gravity modelling indicates that this root has a northeasterly strike, slightly oblique to the ENE general orientation of the High Atlas belt. A consequence of the obliquity between the High Atlas borders and its internal and deep structure is the lack of correlation between Bouguer gravity anomaly values and topography. Active buckling affecting the crust, a highly elevated asthenosphere, or a combination of both are addressed as side mechanisms that help to maintain the high elevations of the Atlas mountains.

A high performance image processing platform based on CPU-GPU heterogeneous cluster with parallel image reconstroctions for micro-CT

International Nuclear Information System (INIS)

Ding Yu; Qi Yujin; Zhang Xuezhu; Zhao Cuilan

2011-01-01

In this paper, we report the development of a high-performance image processing platform, which is based on CPU-GPU heterogeneous cluster. Currently, it consists of a Dell Precision T7500 and HP XW8600 workstations with parallel programming and runtime environment, using the message-passing interface (MPI) and CUDA (Compute Unified Device Architecture). We succeeded in developing parallel image processing techniques for 3D image reconstruction of X-ray micro-CT imaging. The results show that a GPU provides a computing efficiency of about 194 times faster than a single CPU, and the CPU-GPU clusters provides a computing efficiency of about 46 times faster than the CPU clusters. These meet the requirements of rapid 3D image reconstruction and real time image display. In conclusion, the use of CPU-GPU heterogeneous cluster is an effective way to build high-performance image processing platform. (authors)

Numerical calculations on heterogeneity of groundwater flow

International Nuclear Information System (INIS)

Follin, S.

1992-01-01

The upscaling of model parameters is a key issue in many research fields concerned with parameter heterogeneity. The upscaling process allows for fewer model blocks and relaxes the numerical problems caused by high contrasts in the hydraulic conductivity. The trade-offs are dependent on the object but the general drawback is an increasing uncertainty about the representativeness. The present study deals with numerical calculations of heterogeneity of groundwater flow and solute transport in hypothetical blocks of fractured hard rock in a '3m scale' and addresses both conceptual and practical problems in numerical simulation. Evidence that the hydraulic conductivity (K) of the rock mass between major fracture zones is highly heterogeneous in a 3m scale is provided by a large number of field investigations. The present uses the documented heterogeneity and investigates flow and transport in a two-dimensional stochastic continuum characterized by a variance in Y = In(K) of σ y 2 = 16, corresponding to about 12 log 10 cycles in K. The study considers anisotropy, channelling, non-Fickian and Fickian transport, and conditional simulation. The major conclusions are: * heterogeneity gives rise to anisotropy in the upscaling process, * the choice of support scale is crucial for the modelling of solute transport. As a consequence of the obtained results, a two-dimensional stochastic discontinuum model is presented, which provides a tool for linking stochastic continuum models to discrete fracture network models. (au) (14 figs., 136 refs.)

Assessment of Deep Geological Environmental Condition for HLW Disposal in Korea

International Nuclear Information System (INIS)

Koh, Yong Kweon; Bae, Dae Seok; Kim, Kyung Su

2010-04-01

The research developed methods to study and evaluate geological factors and items to select radioactive waste disposal site, which should meet the safety requirements for radioactive waste disposal repositories according to the guidelines recommended by IAEA. A basic concept of site evaluation and selection for high level radioactive waste disposal and develop systematic geological data management with geological data system which will be used for site selection in future are provided. We selected 36 volcanic rock sites and 26 gneissic sites as the alternative host rocks for high level radioactive waste disposal and the geochemical characteristics of groundwaters of the four representative sites were statistically analyzed. From the hydrogeological and geochemical investigation, the spatial distribution characteristics were provided for the disposal system development and preliminary safety assessment. Finally, the technology and scientific methods were developed to obtain accurate data on the hydrogeological and geochemical characteristics of the deep geological environments

Dynamic effective properties of heterogeneous geological formations with spherical inclusions under periodic time variations

Science.gov (United States)

Rabinovich, A.; Dagan, G.; Miloh, T.

2013-04-01

In unsteady groundwater flow (or similar processes of heat/electrical conduction), the heterogeneous medium structure is characterized by two random properties, the conductivity K and the specific storativity S. The average head field ⟨H ⟩and the associated effective properties Kef, Sef are determined for a layer with a periodic head drop between boundaries, such that H is periodic in time, and a medium made up of a matrix with a dilute concentration of spherical inclusions. In the common quasi-steady approximation, Kef is equal to the classical steady solution while Sef = SA, the arithmetic mean. We derive expressions for the frequency dependent Kef, Sef, which are generally complex, i.e., dynamic. The main result is the delineation of the ranges of the parameters: dimensionless frequency (ω) and contrasts of conductivity (κ) and storativity (s) between the matrix and the inclusions, for which dynamic effects are significant.

Homogeneous, heterogeneous and enzymatic catalysis for transesterification of high free fatty acid oil (waste cooking oil) to biodiesel: a review.

Science.gov (United States)

Lam, Man Kee; Lee, Keat Teong; Mohamed, Abdul Rahman

2010-01-01

In the last few years, biodiesel has emerged as one of the most potential renewable energy to replace current petrol-derived diesel. It is a renewable, biodegradable and non-toxic fuel which can be easily produced through transesterification reaction. However, current commercial usage of refined vegetable oils for biodiesel production is impractical and uneconomical due to high feedstock cost and priority as food resources. Low-grade oil, typically waste cooking oil can be a better alternative; however, the high free fatty acids (FFA) content in waste cooking oil has become the main drawback for this potential feedstock. Therefore, this review paper is aimed to give an overview on the current status of biodiesel production and the potential of waste cooking oil as an alternative feedstock. Advantages and limitations of using homogeneous, heterogeneous and enzymatic transesterification on oil with high FFA (mostly waste cooking oil) are discussed in detail. It was found that using heterogeneous acid catalyst and enzyme are the best option to produce biodiesel from oil with high FFA as compared to the current commercial homogeneous base-catalyzed process. However, these heterogeneous acid and enzyme catalyze system still suffers from serious mass transfer limitation problems and therefore are not favorable for industrial application. Nevertheless, towards the end of this review paper, a few latest technological developments that have the potential to overcome the mass transfer limitation problem such as oscillatory flow reactor (OFR), ultrasonication, microwave reactor and co-solvent are reviewed. With proper research focus and development, waste cooking oil can indeed become the next ideal feedstock for biodiesel.

Global Journal of Geological Sciences: Editorial Policies

African Journals Online (AJOL)

Focus and Scope. Global Journal of Geological Sciences is aimed at promoting research in all areas of geological Sciences including Petrology, Mineralogy, geophysics, hydrogeology, Engineering geology, Petroleum geology, Palaeontology, environmental geology, Economic geology, etc.

Contaminant transport in fracture networks with heterogeneous rock matrices. The Picnic code

International Nuclear Information System (INIS)

Barten, Werner; Robinson, Peter C.

2001-02-01

these geometries relies chiefly on the verification for one-dimensional matrix diffusion, on qualitative estimates and on different self-consistency tests. The steady-state release for a single nuclide is additionally verified quantitatively. PICNIC has been verified as far as possible at present to allow application with confidence in performance assessment and in modelling of transport experiments. It is shown that structural geological information on small-scale heterogeneity can be entered easily into PICNIC. It is explained, e.g. that considering two-dimensional matrix diffusion into the layer of altered wall rock adjacent to open channels in the cataclastic zone can strongly increase the performance of the geosphere for migrating radionuclides, depending however on the properties of the nuclides and the rock. Considering the effects of matrix diffusion into a second rock layer can also be highly beneficial. (author)

Contaminant transport in fracture networks with heterogeneous rock matrices. The Picnic code

Energy Technology Data Exchange (ETDEWEB)

Barten, Werner [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Robinson, Peter C. [QuantiSci Limited, Henley-on-Thames (United Kingdom)

2001-02-01

verification for these geometries relies chiefly on the verification for one-dimensional matrix diffusion, on qualitative estimates and on different self-consistency tests. The steady-state release for a single nuclide is additionally verified quantitatively. PICNIC has been verified as far as possible at present to allow application with confidence in performance assessment and in modelling of transport experiments. It is shown that structural geological information on small-scale heterogeneity can be entered easily into PICNIC. It is explained, e.g. that considering two-dimensional matrix diffusion into the layer of altered wall rock adjacent to open channels in the cataclastic zone can strongly increase the performance of the geosphere for migrating radionuclides, depending however on the properties of the nuclides and the rock. Considering the effects of matrix diffusion into a second rock layer can also be highly beneficial. (author)

PROCESS FOR LICENSE APPLICATION DEVELOPMENT FOR THE GEOLOGIC REPOSITORY

International Nuclear Information System (INIS)

DOUGLAS M. FRANKS AND NORMAN C. HENDERSON

1997-01-01

The Department of Energy (DOE), specifically the Office of Civilian Radioactive Waste Management (OCRWM) has been charged by the U.S. Congress, through the Nuclear Waste Policy Act (NWPA), with the responsibility for obtaining a license to develop a geologic repository. The NRC is the licensing authority for geologic disposal, and its regulations pertinent to construction authorization and license application are specified in 10 CFR Part 60, Disposal of High-Level Radioactive Wastes in Geologic Repositories, (section)60.21ff and (section)60.31ff. This paper discusses the process the Yucca Mountain Site Site Characterization Project (YMP) will use to identify and apply regulatory and industry guidance to development of the license application (LA) for a geologic repository at Yucca Mountain, Nevada. This guidance will be implemented by the ''Technical Guidance Document for Preparation of the License Application'' (TGD), currently in development

Process for license application development for the geologic repository

International Nuclear Information System (INIS)

Franks, D.M.; Henderson, N.C.

1998-01-01

The Department of Energy (DOE), specifically the Office of Civilian Radioactive Waste Management (OCRWM) has been charged by the US Congress, through the Nuclear Waste Policy Act (NWPA), with the responsibility for obtaining a license to develop a geologic repository. The NRC is the licensing authority for geologic disposal, and its regulations pertinent to construction authorization and license application are specified in 10 CFR Part 60, Disposal of High-Level Radioactive Wastes in Geologic Repositories, section 60.21ff and section 60.31ff. This paper discusses the process the Yucca Mountain Site Characterization Project (YMP) will use to identify and apply regulatory and industry guidance to development of the license application (LA) for a geologic repository at Yucca Mountain, Nevada. This guidance will be implemented by the Technical Guidance Document for Preparation of the License Application (TGD), currently in development

Heterogeneous all-solid multicore fiber based multipath Michelson interferometer for high temperature sensing.

Science.gov (United States)

Duan, Li; Zhang, Peng; Tang, Ming; Wang, Ruoxu; Zhao, Zhiyong; Fu, Songnian; Gan, Lin; Zhu, Benpeng; Tong, Weijun; Liu, Deming; Shum, Perry Ping

2016-09-05

A compact high temperature sensor utilizing a multipath Michelson interferometer (MI) structure based on weak coupling multicore fiber (MCF) is proposed and experimentally demonstrated. The device is fabricated by program-controlled tapering the spliced region between single mode fiber (SMF) and a segment of MCF. After that, a spherical reflective structure is formed by arc-fusion splicing the end face of MCF. Theoretical analysis has been implemented for this specific multipath MI structure; beam propagation method based simulation and corresponding experiments were performed to investigate the effect of taper and spherical end face on system's performance. Benefiting from the multipath interferences and heterogeneous structure between the center core and surrounding cores of the all-solid MCF, an enhanced temperature sensitivity of 165 pm/°C up to 900°C and a high-quality interference spectrum with 25 dB fringe visibility were achieved.

Nano-catalysts: Bridging the gap between homogeneous and heterogeneous catalysis

Science.gov (United States)

Functionalized nanoparticles have emerged as sustainable alternatives to conventional materials, as robust, high-surface-area heterogeneous catalyst supports. We envisioned a catalyst system, which can bridge the homogenous and heterogeneous system. Postsynthetic surface modifica...

USC Undergraduate Team Research, Geological Field Experience and Outdoor Education in the Tuolumne Batholith and Kings Canyon, High Sierra Nevada

Science.gov (United States)

Culbert, K. N.; Anderson, J. L.; Cao, W.; Chang, J.; Ehret, P.; Enriquez, M.; Gross, M. B.; Gelbach, L. B.; Hardy, J.; Paterson, S. R.; Ianno, A.; Iannone, M.; Memeti, V.; Morris, M.; Lodewyk, J.; Davis, J.; Stanley, R.; van Guilder, E.; Whitesides, A. S.; Zhang, T.

2009-12-01

Within four years, USC’s College of Letters, Arts and Sciences and Earth Science department have successfully launched the revolutionary undergraduate team research (UTR) program “Geologic Wonders of Yosemite at Two Miles High”. A diverse group of professors, graduate students and undergraduates spent two weeks mapping the Boyden Cave in Kings Canyon National Park, the Iron Mountain pendants south of Yosemite, the Western Metamorphic belt along the Merced River, and the Tuolumne Batholith (TB) in June and August 2009. During their experience in the field, the undergraduates learned geologic field techniques from their peers, professors, and experienced graduate students and developed ideas that will form the basis of the independent and group research projects. Apart from teaching undergraduates about the geology of the TB and Kings Canyon, the two weeks in the field were also rigorous exercise in critical thinking and communication. Every day spent in the field required complete cooperation between mentors and undergraduates in order to successfully gather and interpret the day’s data. Undergraduates were to execute the next day’s schedule and divide mapping duties among themselves. The two-week field experience was also the ideal setting in which to learn about the environmental impacts of their work and the actions of others. The UTR groups quickly adapted to the demanding conditions of the High Sierra—snow, grizzly bears, tourists, and all. For many of the undergraduates, the two weeks spent in the field was their first experience with field geology. The vast differences in geological experience among the undergraduates proved to be advantageous to the ‘team-teaching’ focus of the program: more experienced undergraduates were able to assist less experienced undergraduates while cementing their own previously gained knowledge about geology. Over the rest of the academic year, undergraduates will learn about the research process and scientific

Information Extraction of Tourist Geological Resources Based on 3d Visualization Remote Sensing Image

Science.gov (United States)

Wang, X.

2018-04-01

Tourism geological resources are of high value in admiration, scientific research and universal education, which need to be protected and rationally utilized. In the past, most of the remote sensing investigations of tourism geological resources used two-dimensional remote sensing interpretation method, which made it difficult for some geological heritages to be interpreted and led to the omission of some information. This aim of this paper is to assess the value of a method using the three-dimensional visual remote sensing image to extract information of geological heritages. skyline software system is applied to fuse the 0.36 m aerial images and 5m interval DEM to establish the digital earth model. Based on the three-dimensional shape, color tone, shadow, texture and other image features, the distribution of tourism geological resources in Shandong Province and the location of geological heritage sites were obtained, such as geological structure, DaiGu landform, granite landform, Volcanic landform, sandy landform, Waterscapes, etc. The results show that using this method for remote sensing interpretation is highly recognizable, making the interpretation more accurate and comprehensive.

Mercury compositional units inferred by MDIS. A comparison with the geology in support to the BepiColombo mission

Science.gov (United States)

Zambon, Francesca; Carli, Cristian; Galluzzi, Valentina; Capaccioni, Fabrizio; Filacchione, Gianrico; Giacomini, Lorenza; Massirioni, Matteo; Palumbo, Pasquale

2016-04-01

Mercury has been explored by two spatial missions. Mariner 10 acquired 45% of the surface during three Hermean flybys in 1974, giving a first close view of the planet. The recent MESSENGER mission globally mapped the planet and contributed to understand many unsolved issues about Mercury (Solomon et al., 2007). Nevertheless, even after MESSENGER, Mercury surface composition remains still unclear, and the correlation between morphology and compositional heterogeneity is not yet well understood. Thanks to the Mercury Dual Imaging System (MDIS), onboard MESSENGER, a global coverage of Mercury surface with variable spatial resolution has been done. MDIS is equipped with a Narrow Angle Camera (NAC), dedicated to the high-resolution study of the surface morphology and a Wide Angle Camera (WAC) with 12 filters useful to investigate the surface composition (Hawkins et al., 2007). Several works were focused on the different terrains present on Mercury, in particular, Denevi et al. (2013) observes that ~27% of Hermean surface is covered by volcanic origin smooth plains. These plains show differences in composition associated to spectral slope variation. High-reflectance red plains (HRP), with spectral slope greater than the average and low-reflectance blue plains (LBP), with spectral slope lesser than the average has been identified. This spectral variations could be correlated with different chemical composition. The X-Ray Spectrometer (XRS) data show that HRP-type areas are associated with a low-Fe basalt-like composition, while the LBP are also Fe poor but are rich in Mg/Si and Ca/Si and with lower Al/Si and are interpreted as more ultramafic (Nittler et al., 2011; Weider et al., 2012; Denevi at al., 2013, Weider et al., 2014). In these work we produce high resolution multicolor mosaic to found a possible link between morphology and composition. The spectral properties have been used to define the principal units of Mercury's surface or to characterize other globally

High temporal resolution mapping of seismic noise sources using heterogeneous supercomputers

Science.gov (United States)

Gokhberg, Alexey; Ermert, Laura; Paitz, Patrick; Fichtner, Andreas

2017-04-01

Time- and space-dependent distribution of seismic noise sources is becoming a key ingredient of modern real-time monitoring of various geo-systems. Significant interest in seismic noise source maps with high temporal resolution (days) is expected to come from a number of domains, including natural resources exploration, analysis of active earthquake fault zones and volcanoes, as well as geothermal and hydrocarbon reservoir monitoring. Currently, knowledge of noise sources is insufficient for high-resolution subsurface monitoring applications. Near-real-time seismic data, as well as advanced imaging methods to constrain seismic noise sources have recently become available. These methods are based on the massive cross-correlation of seismic noise records from all available seismic stations in the region of interest and are therefore very computationally intensive. Heterogeneous massively parallel supercomputing systems introduced in the recent years combine conventional multi-core CPU with GPU accelerators and provide an opportunity for manifold increase and computing performance. Therefore, these systems represent an efficient platform for implementation of a noise source mapping solution. We present the first results of an ongoing research project conducted in collaboration with the Swiss National Supercomputing Centre (CSCS). The project aims at building a service that provides seismic noise source maps for Central Europe with high temporal resolution (days to few weeks depending on frequency and data availability). The service is hosted on the CSCS computing infrastructure; all computationally intensive processing is performed on the massively parallel heterogeneous supercomputer "Piz Daint". The solution architecture is based on the Application-as-a-Service concept in order to provide the interested external researchers the regular access to the noise source maps. The solution architecture includes the following sub-systems: (1) data acquisition responsible for

Image-based computational quantification and visualization of genetic alterations and tumour heterogeneity.

Science.gov (United States)

Zhong, Qing; Rüschoff, Jan H; Guo, Tiannan; Gabrani, Maria; Schüffler, Peter J; Rechsteiner, Markus; Liu, Yansheng; Fuchs, Thomas J; Rupp, Niels J; Fankhauser, Christian; Buhmann, Joachim M; Perner, Sven; Poyet, Cédric; Blattner, Miriam; Soldini, Davide; Moch, Holger; Rubin, Mark A; Noske, Aurelia; Rüschoff, Josef; Haffner, Michael C; Jochum, Wolfram; Wild, Peter J

2016-04-07

Recent large-scale genome analyses of human tissue samples have uncovered a high degree of genetic alterations and tumour heterogeneity in most tumour entities, independent of morphological phenotypes and histopathological characteristics. Assessment of genetic copy-number variation (CNV) and tumour heterogeneity by fluorescence in situ hybridization (ISH) provides additional tissue morphology at single-cell resolution, but it is labour intensive with limited throughput and high inter-observer variability. We present an integrative method combining bright-field dual-colour chromogenic and silver ISH assays with an image-based computational workflow (ISHProfiler), for accurate detection of molecular signals, high-throughput evaluation of CNV, expressive visualization of multi-level heterogeneity (cellular, inter- and intra-tumour heterogeneity), and objective quantification of heterogeneous genetic deletions (PTEN) and amplifications (19q12, HER2) in diverse human tumours (prostate, endometrial, ovarian and gastric), using various tissue sizes and different scanners, with unprecedented throughput and reproducibility.

NRC regulations for disposal of high-level radioactive wastes in geologic repositories: technical criteria

International Nuclear Information System (INIS)

Martin, J.B.; Bell, M.J.; Regnier, E.P.

1983-01-01

The Nuclear Regulatory Commission is promulgating regulations specifying the technical criteria fo disposal of high-level radioactive wastes in geologic repositories. The proposed rule was published for public comment in July 1981. Public comments have been received and considered by the Commission staff. The Commission will soon approve and publish a revised final rule. While the final rule being considered by the Commission is fundamentally the same as the proposed rule, provisions have been added to permit flexibility in the application of numerical criteria, some detailed design requirements have been deleted, and other changes have been made in response to comments. The rule is consistent with the recently enacted Nuclear Waste Policy Act of 1982

Deep earth fluids and huge metallogenetic belt and fatal geological disaster: 60th anniversary of Professor Du Le-tian engaging in geology

International Nuclear Information System (INIS)

Ou Guangxi; Tao Shizhen; Liu Yinhe

2012-01-01

Professor Du Le-tian has been researching for a long time on scientific relationship between deep earth fluids and hydrocarbon accumulation and metallogenesis, as well as gestation and prediction of disasters. He has contributed greatly to the development of that scientific field. From 6 to 8, July, 2012, 'Workshop on Deep Earth Fluids and Huge Metallogenetic Belt, Fatal Geological Disaster, as well as 60 th Anniversary of Professor Du Le-tian Engaging in Geology' was successfully convened in Beijing, totally with 76 delegates present who were experts, scholars or students from USA, Hong Kong, or various institutes, colleges or universities of China. In the workshop, the scientific presentations discussed were counted up to 49, on aspects of geological processes of deep earth fluids, relationship between earth degassing and hydrocarbon accumulation or metallogenesis, gestating mechanism of volcanic eruptions and strong earthquakes as well as their relations with mine gas outburst, high-temperature and high-pressure experimental earth science, etc.. (authors)

Proceedings of the 39. Brazilian congress on geology. v. 6

International Nuclear Information System (INIS)

1996-01-01

The book presents the 39. Brazilian Congress on Geology works, occurred in Salvador, Bahia, during the period of September 1 to 6, 1996. The meeting main subject - geology and society - reflects the current change epoch. The symposiums revealed the more important actions about geosciences applications to the society in the country. The round tables, structured for the polemical subject debates that involve the geosciences and the mineral sector crisis aspects, were achieved by several invited participants completely embraced with the subject. During the congress activities development there were some courses, technical excursions and external actions in Salvador, aiming to show the geosciences role to the social welfare. This volume focuses papers about geology and metallogenesis from high degree metamorphic terrain and isotope applications in geology

Chloride Transport in Heterogeneous Formation

Science.gov (United States)

Mukherjee, A.; Holt, R. M.

2017-12-01

The chloride mass balance (CMB) is a commonly-used method for estimating groundwater recharge. Observations of the vertical distribution of pore-water chloride are related to the groundwater infiltration rates (i.e. recharge rates). In CMB method, the chloride distribution is attributed mainly to the assumption of one dimensional piston flow. In many places, however, the vertical distribution of chloride will be influenced by heterogeneity, leading to horizontal movement of infiltrating waters. The impact of heterogeneity will be particularly important when recharge is locally focused. When recharge is focused in an area, horizontal movement of chloride-bearing waters, coupled with upward movement driven by evapotranspiration, may lead to chloride bulges that could be misinterpreted if the CMB method is used to estimate recharge. We numerically simulate chloride transport and evaluate the validity of the CMB method in highly heterogeneous systems. This simulation is conducted for the unsaturated zone of Ogallala, Antlers, and Gatuna (OAG) formations in Andrews County, Texas. A two dimensional finite element model will show the movement of chloride through heterogeneous systems. We expect to see chloride bulges not only close to the surface but also at depths characterized by horizontal or upward movement. A comparative study of focused recharge estimates in this study with available recharge data will be presented.

Admissible thermal loading in geological formations. Consequences on radioactive waste disposal methods

International Nuclear Information System (INIS)

1982-01-01

Every granite formation possesses, the following main characteristics: presence of fissures; physico-chemical alterability; presence of internal or peripheral heterogeneities. From samples at ambient temperature, sound granite is found to have the properties of a hard, elastic rock with a relatively low thermal conductivity. Its natural permeability is low or very low, and most of the percolating water passes through fissures affecting the rock mass. In this report are examined: effects of heat on cavity stability, mechanical interaction between conditioned wastes and the geological environment, effects on the stability of infilling materials, heat effects on the host rock and underground water, assessment of the permissible thermal load and design of the storage facility

Assessment of effectiveness of geologic isolation systems: the AEGIS geologic simulation model

International Nuclear Information System (INIS)

Foley, M.G.; Petrie, G.M.

1981-02-01

Assessment of the post-closure performance of a nuclear waste repository has two basic components: the identification and analysis of potentially disruptive sequences and the pattern of geologic events and processes causing each sequence, and the identification and analysis of the environmental consequences of radionuclide transport and interactions subsequent to disruption of a repository. The AEGIS Scenario Analysis Task is charged with identifying and analyzing potenially disruptive sequences of geologic events and processes. The Geologic Simulation Model (GSM) was developed to evaluate the geologic/hydrologic system surrounding an underground repository, and describe the phenomena that alone, or in concert, could perturb the system and possibly cause a loss of repository integrity. The AEGIS approach is described in this report. It uses an integrated series of models for repository performance analysis; the GSM for a low-resolution, long-term, comprehensive evaluation of the geologic/hydrologic system, followed by more detailed hydrogeologic, radionuclide transport, and dose models to more accurately assess the consequences of disruptive sequences selected from the GSM analyses. This approach is felt to be more cost-effective than an integrated one because the GSM can be used to estimate the likelihoods of different potentially disruptive future evolutionary developments within the geologic/hydrologic system. The more costly consequence models can then be focused on a few disruptive sequences chosen for their representativeness and effective probabilities

Challenges in conditioning a stochastic geological model of a heterogeneous glacial aquifer to a comprehensive soft data set

DEFF Research Database (Denmark)

Koch, Julian; He, Xin; Jensen, Karsten Høgh

2014-01-01

In traditional hydrogeological investigations, one geological model is often used based on subjective interpretations and sparse data availability. This deterministic approach usually does not account for any uncertainties. Stochastic simulation methods address this problem and can capture......TEM data set are derived from a histogram probability matching method, where resistivity is paired with the corresponding lithology from the categorized borehole data. This study integrates two distinct data sources into the stochastic modeling process that represent two extremes of the conditioning...

Geological studies in Alaska by the U.S. Geological Survey, 1999

Science.gov (United States)

Gough, Larry P.; Wilson, Frederic H.

2001-01-01

The collection of nine papers that follow continue the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. The series presents new and sometimes preliminary findings that are of interest to earth scientists in academia, government, and industry; to land and resource managers; and to the general public. Reports presented in Geologic Studies in Alaska cover a broad spectrum of topics from various parts of the State (fig. 1), serving to emphasize the diversity of USGS efforts to meet the Nation's needs for earth-science information in Alaska.

Reconstructing mantle heterogeneity with data assimilation based on the back-and-forth nudging method: Implications for mantle-dynamic fitting of past plate motions

Science.gov (United States)

Glišović, Petar; Forte, Alessandro

2016-04-01

The paleo-distribution of density variations throughout the mantle is unknown. To address this question, we reconstruct 3-D mantle structure over the Cenozoic era using a data assimilation method that implements a new back-and-forth nudging algorithm. For this purpose, we employ convection models for a compressible and self-gravitating mantle that employ 3-D mantle structure derived from joint seismic-geodynamic tomography as a starting condition. These convection models are then integrated backwards in time and are required to match geologic estimates of past plate motions derived from marine magnetic data. Our implementation of the nudging algorithm limits the difference between a reconstruction (backward-in-time solution) and a prediction (forward-in-time solution) on over a sequence of 5-million-year time windows that span the Cenozoic. We find that forward integration of reconstructed mantle heterogeneity that is constrained to match past plate motions delivers relatively poor fits to the seismic-tomographic inference of present-day mantle heterogeneity in the upper mantle. We suggest that uncertainties in the past plate motions, related for example to plate reorganization episodes, could partly contribute to the poor match between predicted and observed present-day heterogeneity. We propose that convection models that allow tectonic plates to evolve freely in accord with the buoyancy forces and rheological structure in the mantle could provide additional constraints on geologic estimates of paleo-configurations of the major tectonic plates.

A conceptual sedimentological-geostatistical model of aquifer heterogeneity based on outcrop studies

International Nuclear Information System (INIS)

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

A conceptual sedimentological-geostatistical model of aquifer heterogeneity based on outcrop studies

Energy Technology Data Exchange (ETDEWEB)

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.

Visual Analytics for Heterogeneous Geoscience Data

Science.gov (United States)

Pan, Y.; Yu, L.; Zhu, F.; Rilee, M. L.; Kuo, K. S.; Jiang, H.; Yu, H.

2017-12-01

Geoscience data obtained from diverse sources have been routinely leveraged by scientists to study various phenomena. The principal data sources include observations and model simulation outputs. These data are characterized by spatiotemporal heterogeneity originated from different instrument design specifications and/or computational model requirements used in data generation processes. Such inherent heterogeneity poses several challenges in exploring and analyzing geoscience data. First, scientists often wish to identify features or patterns co-located among multiple data sources to derive and validate certain hypotheses. Heterogeneous data make it a tedious task to search such features in dissimilar datasets. Second, features of geoscience data are typically multivariate. It is challenging to tackle the high dimensionality of geoscience data and explore the relations among multiple variables in a scalable fashion. Third, there is a lack of transparency in traditional automated approaches, such as feature detection or clustering, in that scientists cannot intuitively interact with their analysis processes and interpret results. To address these issues, we present a new scalable approach that can assist scientists in analyzing voluminous and diverse geoscience data. We expose a high-level query interface that allows users to easily express their customized queries to search features of interest across multiple heterogeneous datasets. For identified features, we develop a visualization interface that enables interactive exploration and analytics in a linked-view manner. Specific visualization techniques such as scatter plots to parallel coordinates are employed in each view to allow users to explore various aspects of features. Different views are linked and refreshed according to user interactions in any individual view. In such a manner, a user can interactively and iteratively gain understanding into the data through a variety of visual analytics operations. We

Annotated bibliography for the design of waste packages for geologic disposal of spent fuel and high-level waste

International Nuclear Information System (INIS)

Wurm, K.J.; Miller, N.E.

1982-11-01

This bibliography identifies documents that are pertinent to the design of waste packages for geologic disposal of nuclear waste. The bibliography is divided into fourteen subject categories so that anyone wishing to review the subject of leaching, for example, can turn to the leaching section and review the abstracts of reports which are concerned primarily with leaching. Abstracts are also cross referenced according to secondary subject matter so that one can get a complete list of abstracts for any of the fourteen subject categories. All documents which by their title alone appear to deal with the design of waste packages for the geologic disposal of spent fuel or high-level waste were obtained and reviewed. Only those documents which truly appear to be of interest to a waste package designer were abstracted. The documents not abstracted are listed in a separate section. There was no beginning date for consideration of a document for review. About 1100 documents were reviewed and about 450 documents were abstracted

Engineering-Geological Data Model - The First Step to Build National Polish Standard for Multilevel Information Management

Science.gov (United States)

Ryżyński, Grzegorz; Nałęcz, Tomasz

2016-10-01

The efficient geological data management in Poland is necessary to support multilevel decision processes for government and local authorities in case of spatial planning, mineral resources and groundwater supply and the rational use of subsurface. Vast amount of geological information gathered in the digital archives and databases of Polish Geological Survey (PGS) is a basic resource for multi-scale national subsurface management. Data integration is the key factor to allow development of GIS and web tools for decision makers, however the main barrier for efficient geological information management is the heterogeneity of data in the resources of the Polish Geological Survey. Engineering-geological database is the first PGS thematic domain applied in the whole data integration plan. The solutions developed within this area will facilitate creation of procedures and standards for multilevel data management in PGS. Twenty years of experience in delivering digital engineering-geological mapping in 1:10 000 scale and archival geotechnical reports acquisition and digitisation allowed gathering of more than 300 thousands engineering-geological boreholes database as well as set of 10 thematic spatial layers (including foundation conditions map, depth to the first groundwater level, bedrock level, geohazards). Historically, the desktop approach was the source form of the geological-engineering data storage, resulting in multiple non-correlated interbase datasets. The need for creation of domain data model emerged and an object-oriented modelling (UML) scheme has been developed. The aim of the aforementioned development was to merge all datasets in one centralised Oracle server and prepare the unified spatial data structure for efficient web presentation and applications development. The presented approach will be the milestone toward creation of the Polish national standard for engineering-geological information management. The paper presents the approach and methodology

Heterogeneous network architectures

DEFF Research Database (Denmark)

Christiansen, Henrik Lehrmann

2006-01-01

is flexibility. This thesis investigates such heterogeneous network architectures and how to make them flexible. A survey of algorithms for network design is presented, and it is described how using heuristics can increase the speed. A hierarchical, MPLS based network architecture is described......Future networks will be heterogeneous! Due to the sheer size of networks (e.g., the Internet) upgrades cannot be instantaneous and thus heterogeneity appears. This means that instead of trying to find the olution, networks hould be designed as being heterogeneous. One of the key equirements here...... and it is discussed that it is advantageous to heterogeneous networks and illustrated by a number of examples. Modeling and simulation is a well-known way of doing performance evaluation. An approach to event-driven simulation of communication networks is presented and mixed complexity modeling, which can simplify...

Thermal loading effects on geological disposal

International Nuclear Information System (INIS)

Come, B.; Venet, P.

1984-01-01

A joint study on the thermal loading effects on geological disposal was carried out within the European Community Programme on Management and Storage of Radioactive Waste by several laboratories in Belgium, France and the Federal Republic of Germany. The purpose of the work was to review the thermal effects induced by the geological disposal of high-level wastes and to assess their consequences on the 'admissible thermal loading' and on waste management in general. Three parallel studies dealt separately with the three geological media being considered for HLW disposal within the CEC programme: granite (leadership: Commissariat a l'energie atomique (CEA), France), salt (leadership: Gesellschaft fuer Strahlen- und Umweltforschung (GSF), Federal Republic of Germany), and clay (leadership: Centre d'etude de l'energie nucleaire (CEN/SCK), Belgium). The studies were based on the following items: only vitrified high-level radioactive waste was considered; the multi-barrier confinement concept was assumed (waste glass, container (with or without overpack), buffer material, rock formation); the disposal was foreseen in a deep mined repository, in an 'in-land' geological formation; only normal situations and processes were covered, no 'accident' scenario being taken into account. Although reasonably representative of a wide variety of situations, the data collected and the results obtained are generic for granite, formation-specific for salt (i.e. related to the north German Zechstein salt formation), and site-specific for clay (i.e. concentrated on the Boom clay layer at the Mol site, Belgium). For each rock type, realistic temperature limits were set, taking into account heat propagation, thermo-mechanical effects inside the rock formations, induced or modified groundwater or brine movement, effects on the buffer material as well as effects on the waste glass and canister, and finally, nuclide transport

Dynamic Pore-Scale Imaging of Reactive Transport in Heterogeneous Carbonates at Reservoir Conditions Across Multiple Dissolution Regimes

Science.gov (United States)

Menke, H. P.; Bijeljic, B.; Andrew, M. G.; Blunt, M. J.

2014-12-01

Sequestering carbon in deep geologic formations is one way of reducing anthropogenic CO2 emissions. When supercritical CO2 mixes with brine in a reservoir, the acid generated has the potential to dissolve the surrounding pore structure. However, the magnitude and type of dissolution are condition dependent. Understanding how small changes in the pore structure, chemistry, and flow properties affect dissolution is paramount for successful predictive modelling. Both 'Pink Beam' synchrotron radiation and a Micro-CT lab source are used in dynamic X-ray microtomography to investigate the pore structure changes during supercritical CO2 injection in carbonate rocks of varying heterogeneity at high temperatures and pressures and various flow-rates. Three carbonate rock types were studied, one with a homogeneous pore structure and two heterogeneous carbonates. All samples are practically pure calcium carbonate, but have widely varying rock structures. Flow-rate was varied in three successive experiments by over an order of magnitude whlie keeping all other experimental conditions constant. A 4-mm carbonate core was injected with CO2-saturated brine at 10 MPa and 50oC. Tomographic images were taken at 30-second to 20-minute time-resolutions during a 2 to 4-hour injection period. A pore network was extracted using a topological analysis of the pore space and pore-scale flow modelling was performed directly on the binarized images with connected pathways and used to track the altering velocity distributions. Significant differences in dissolution type and magnitude were found for each rock type and flowrate. At the highest flow-rates, the homogeneous carbonate was seen to have predominately uniform dissolution with minor dissolution rate differences between the pores and pore throats. Alternatively, the heterogeneous carbonates which formed wormholes at high flow rates. At low flow rates the homogeneous rock developed wormholes, while the heterogeneous samples showed evidence

Study on the Geological Structure around KURT Using a Deep Borehole Investigation

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Su; Koh, Yong Kwon; Choi, Jong Won

2010-01-01

To characterize geological features in study area for high-level radioactive waste disposal research, KAERI (Korea Atomic Energy Research Institute) has been performing the several geological investigations such as geophysical surveys and borehole drilling since 1997. Especially, the KURT (KAERI Underground Research Tunnel) constructed to understand the deep geological environments in 2006. Recently, the deep borehole of 500 m depths was drilled to confirm and validate the geological model at the left research module of the KURT. The objective of this research was to identify the geological structures around KURT using the data obtained from the deep borehole investigation. To achieve the purpose, several geological investigations such as geophysical and borehole fracture surveys were carried out simultaneously. As a result, 7 fracture zones were identified in deep borehole located in the KURT. As one of important parts of site characterization on KURT area, the results will be used to revise the geological model of the study area

Field implementation of geological steering techniques optimizes drilling in highly-deviated and horizontal wells

Energy Technology Data Exchange (ETDEWEB)

Jackson, C. E.; Illfelder, H. M. J.; Pineda, G.

1998-12-31

Field implementation of an integrated wellsite geological steering service is described. The service provides timely, useful feedback from real-time logging-while-drilling (LWD) measurements for making immediate course corrections. Interactive multi-dimensional displays of both the geological and petrophysical properties of the formation being penetrated by the wellbore are a prominent feature of the service; the optimization of the drilling is the result of the visualization afforded by the displays. The paper reviews forward modelling techniques, provides a detailed explanation of the principles underlying this new application, and illustrates the application by examples from the field. 5 refs., 1 tab., 8 figs.