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Database for Regional Geology, Phase 1– a Tool for Informing Regional Evaluations of Alternative Geologic Media and Decision Making

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Database for Regional Geology, Phase 1– a Tool for Informing Regional Evaluations of Alternative Geologic Media and Decision Making Database for Regional Geology, Phase 1– A Tool for informing Regional Evaluations of Alternative Geologic Media and Decision Making Prepared for U.S. Department of Energy Used Fuel Disposition Campaign Frank V. Perry, Richard E. Kelley, Alexander B. Lugo, Suzanne M. Birdsell, Los Alamos National Laboratory Patrick Dobson, James E. Houseworth Lawrence Berkeley National Laboratory September 24, 2014 FCRD-UFD-2014-000067 Los Alamos Unlimited Release LA-UR-14-27389 DISCLAIMER This information was prepared as an account of work sponsored by an agency of the U.S. Government. Neither the U.S. Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness, of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. References herein to any specific commercial product, process, or service by trade name, trade mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the U.S. Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof. Database for Regional Geology, Phase 1 September 2014 iii EXECUTIVE SUMMARY Phase 1 and 2 Websites for the Regional Geology GIS Database An informational website was completed that allows users to visualize the information contained in the Regional Geology GIS Database. This information includes the distribution of crystalline rock (including basement depth), and salt and shale formations within the contiguous United States. The website provides visualizations of the relationships between geologic media and selected natural and cultural features pertaining to potential siting guidelines for repository siting. The development of this website was Phase 1 of an effort to create a fully interactive web-based mapping application (Phase 2) that will be competed in FY15. The data elements planned for the fully interactive mapping tools are described in this report. Terrane Maps of Crystalline Basement Rocks Siting of a deep borehole disposal or R&D facility requires information about the regional geologic setting and geology of the basement at the national, regional and local scale. We have identified and included a number of state to national-scale basement maps in the GIS database. These will serve as a first step in providing a regional geologic framework for understanding the geologic setting, history and overall lithology of different regions, as well as providing a useful aid in identifying and understanding data at the local scale that will be necessary for comparing specific candidate sites for the purposes of site selection. Inventory of Shale Formations in the US This section provides a summary of the distribution, thickness, and depth of selected shale formations found within many of the sedimentary basins in the contiguous US. Clay-rich shale formations have a number of properties, such as low permeability, high cation exchange potential, and the ability to self- seal, which make them candidates for a geologic repository for high-level radioactive waste. The United States has an abundance of thick shale deposits that span a wide range of geologic ages, mineralogic compositions, and geologic environments, some of which might be suitable for hosting repositories to safeguard radioactive waste. The objective of this report is to build upon previous compilations of shale formations within many of the major sedimentary basins in the US by developing GIS data delineating isopach and structural depth maps for many of these units. These data are being incorporated into the Los Alamos National Laboratory (LANL) digital GIS database being developed for determining host rock distribution and depth/thickness parameters consistent with repository design. Additional rock properties, such as total organic carbon (TOC) abundance and thermal maturity, are also included where available. Rock Properties and In-Situ Conditions for Shale Estimated from Sonic Velocity Measurements This section extends the development of methods to assess hydrological and geomechanical properties and conditions for shale formations based on sonic velocity measurements as reported in Dobson and Houseworth (2013). In that effort, publically available data sets were identified for shales under investigation for nuclear waste disposal in Europe and from shales of interest for oil exploration and production in the North Sea. These data were used in the development of several correlations which link properties to sonic compressional velocity. The advantage of using correlations based on sonic velocity is that properties can be estimated from geophysical logs. This information is often more readily available than direct property measurements on core that would otherwise be required. Furthermore, geophysical logs typically provide a continuous readout along wells that can be more readily used to characterize spatial variability in properties. In this report additional information is provided on the correlation between clay content and sonic velocity presented in Dobson and Houseworth (2013). Additional correlations are developed here between the sonic velocity and thermal properties, i.e., thermal conductivity and specific heat. Correlations between sonic velocity and the van Genuchten capillary Database for Regional Geology, Phase 1 iv September 2014 strength parameter and the van Genuchten pore-size-distribution index are also presented. These van Genuchten parameters can be used for the computation of two-phase capillary pressure and relative permeability parameter functions of saturation. The correlations developed were then used to assess properties and conditions in several shale formations of interest within the United States which have publically available data on sonic velocity. As in the previous study, some of the correlations were found to be weak or poorly defined, indicating that additional independent measurements are desirable to supplement such estimates. Further verification is also needed for many of the parameter estimates for the US shale formations analyzed; therefore, they should be viewed as initial estimates. Database for Regional Geology, Phase 1 September 2014 v CONTENTS EXECUTIVE SUMMARY ......................................................................................................................... iii ACRONYMS .............................................................................................................................................. xii 1. Introduction ........................................................................................................................................ 1 2. Implementation of an Informational Website for the GIS Database .................................................. 1 3. Implementation of an Interactive Web-Based Mapping Application ................................................. 8 4. Terrane Maps of Crystalline Basement Rocks ................................................................................. 11 5. Inventory of Shale Formations in the US ......................................................................................... 17 5.1 INTRODUCTION ................................................................................................................. 17 5.2 INVENTORY OF SHALE FORMATIONS IN THE US ..................................................... 17 5.2.1 INTRODUCTION .................................................................................................... 17 5.2.2 DATA SOURCES..................................................................................................... 17 5.2.3 ISOPACH AND STRUCTURE MAPS .................................................................... 19 5.2.4 TOTAL ORGANIC CARBON AND THERMAL MATURITY MAPS ................. 45 5.2.5 CONCLUSIONS OF SECTION 5 ............................................................................ 53 6. Rock Properties and In-Situ Conditions for Shale Estimated from Sonic Velocity Measurements ................................................................................................................................... 54 6.1 Introduction and Recap of Previous Work ............................................................................. 54 6.2 Estimating clay content .......................................................................................................... 55 6.3 Estimating thermal conductivity and specific heat capacity .................................................. 60 6.3.1 Thermal Conductivity ............................................................................................... 60 6.3.2 Specific Heat ............................................................................................................. 63 6.4 Estimating two-phase flow parameters .................................................................................. 65 6.4.1 Estimating van Genuchten ..................................................................................... 66 6.4.2 Estimating van Genuchten .................................................................................... 69 6.4.3 Estimating Residual Saturations휶 ............................................................................... 70 6.5 Application to US Shale Formations풎
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