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J.A. Rupp

Publications and source records attributed to J.A. Rupp.

6 recordsLinked to original sources
USGS2011

Effects of reduction in porosity and permeability with depth on storage capacity and injectivity in deep saline aquifers: A case study from the Mount Simon Sandstone aquifer

The Upper Cambrian Mount Simon Sandstone is recognized as a deep saline reservoir that has significant potential for geological sequestration in the Midwestern region of the United States. Porosity and permeability values collected from core analyses in rocks from this formation and its lateral equivalents in Indiana, Kentucky, Michigan, and Ohio indicate a predictable relationship with depth owing to a reduction in the pore structure due to the effects of compaction and/or cementation, primarily as quartz overgrowths. The regional trend of decreasing porosity with depth is described by the equation: ϕ ( d ) = 16.36 × e −0.00039* d , where ϕ is the porosity and d is the depth in m. The decrease of porosity with depth generally holds true on a basinwide scale. Bearing in mind local variations in lithologic and petrophysical character within the Mount Simon Sandstone, the source data that were used to predict porosity were utilized to estimate the pore volume available within the reservoir that could potentially serve as storage space for injected CO 2 . The potential storage capacity estimated for the Mount Simon Sandstone in the study area, using efficiency factors of 1%, 5%, 10%, and 15%, is 23,680, 118,418, 236,832, and 355,242 million metric tons of CO 2 , respectively.

Ohio, Illinois, Michigan, Kentucky, West Virginia,↗
USGS2011

Depositional and diagenetic variability within the Cambrian Mount Simon Sandstone: Implications for carbon dioxide sequestration

The Cambrian Mount Simon Sandstone is the major target reservoir for ongoing geologic carbon dioxide (CO 2 ) sequestration demonstrations throughout the midwest United States. The potential CO 2 reservoir capacity, reactivity, and ultimate fate of injected CO 2 depend on textural and compositional properties determined by depositional and diagenetic histories that vary vertically and laterally across the formation. Effective and efficient prediction and use of the available pore space requires detailed knowledge of the depositional and diagenetic textures and mineralogy, how these variables control the petrophysical character of the reservoir, and how they vary spatially. Here, we summarize the reservoir characteristics of the Mount Simon Sandstone based on examination of geophysical logs, cores, cuttings, and analysis of more than 150 thin sections. These samples represent different parts of the formation and depth ranges of more than 9000 ft ( 2743 m) across the Illinois Basin and surrounding areas. This work demonstrates that overall reservoir quality and, specifically, porosity do not exhibit a simple relationship with depth, but vary both laterally and with depth because of changes in the primary depositional facies, framework composition (i.e., feldspar concentration), and diverse diagenetic modifications. Diagenetic processes that have been significant in modifying the reservoir include formation of iron oxide grain coatings, chemical compaction, feldspar precipitation and dissolution, multiple generations of quartz overgrowth cementation, clay mineral precipitation, and iron oxide cementation. These variables provide important inputs for calculating CO 2 capacity potential, modeling reactivity, and are also an important baseline for comparisons after CO 2 injection.

Indiana↗
USGS2010

Variations in coal characteristics and their possible implications for CO2 sequestration: Tanquary injection site, southeastern Illinois, USA

As part of the U.S. Department of Energy's Regional Sequestration Partnership program, the potential for sequestering CO2 in the largest bituminous coal reserve in United States - the Illinois Basin - is being assessed at the Tanquary site in Wabash County, southeastern Illinois. To accomplish the main project objectives, which are to determine CO2 injection rates and storage capacity, we developed a detailed coal characterization program. The targeted Springfield Coal occurs at 274m (900ft) depth, is 2.1m (7ft) thick, and is of high volatile B bituminous rank, having an average vitrinite reflectance (Ro) of 0.63%. Desorbed Springfield Coal gas content in cores from four wells ~15 to ~30m (50 to 100ft) apart varies from 4.7-6.6cm3/g (150 to 210scf/ton, dmmf) and consists, generally, of >92% CH4 with lesser amounts of N2 and then CO2. Adsorption isotherms indicate that at least three molecules of CO2 can be stored for each displaced CH4 molecule. Whole seam petrographic composition, which affects sequestration potential, averages 76.5% vitrinite, 4.2% liptinite, 11.6% inertinite, and 7.7% mineral matter. Sulfur content averages 1.59%. Well-developed coal cleats with 1 to 2cm spacing contain partial calcite and/or kaolinite fillings that may decrease coal permeability. The shallow geophysical induction log curves show much higher resistivity in the lower part of the Springfield Coal than the medium or deep curves because of invasion by freshwater drilling fluid, possibly indicating higher permeability. Gamma-ray and bulk density vary, reflecting differences in maceral, ash, and pyrite content. Because coal properties vary across the basin, it is critical to characterize injection site coals to best predict the potential for CO2 injection and storage capacity. ?? 2010 Elsevier B.V.

International Journal of Coal Geology↗
USGS2005

Geometry and kinematics of Late Cretaceous inversion structures in the Jiuquan Basin, western China

Late Cretaceous inversion structures, which are significant for oil and gas accumulation, are widely distributed throughout the Jiuquan Basin. These structures are primarily made up of inverted faults and fault-related folds. Most of the axial planes of folds are parallel to inverted faults trending north-east, indicating that the principal stress direction was north-west - south-east in the Late Cretaceous. The average inversion ratios of faults in the four sags that were investigated are 0.39, 0.29, 0.38, 0.32. The average inversion ratio in the Jiuquan Basin is 0.34 and the degree of inversion is moderate to strong. As moderate inversion is suitable for forming excellent hydrocarbon traps, there is considered to be significant potential in the basin for the presence of structural traps. ?? 2005 Elsevier Ltd. All rights reserved.

Cretaceous Research↗
USGS1997

Seismic interpretation of the deep structure of the Wabash Valley Fault System

Interpretations of newly available seismic reflection profiles near the center of the Illinois Basin indicate that the Wabash Valley Fault System is rooted in a series of basement-penetrating faults. The fault system is composed predominantly of north-northeast-trending high-angle normal faults. The largest faults in the system bound the 22-km wide 40-km long Grayville Graben. Structure contour maps drawn on the base of the Mount Simon Sandstone (Cambrian System) and a deeper pre-Mount Simon horizon show dip-slip displacements totaling at least 600 meters across the New Harmony fault. In contrast to previous interpretations, the N-S extent of significant fault offsets is restricted to a region north of 38° latitude and south of 38.35° latitude. This suggests that the graben is not a NE extension of the structural complex composed of the Rough Creek Fault System and the Reelfoot Rift as previously interpreted. Structural complexity on the graben floor also decreases to the south. Structural trends north of 38° latitude are offset laterally across several large faults, indicating strike-slip motions of 2 to 4 km. Some of the major faults are interpreted to penetrate to depths of 7 km or more. Correlation of these faults with steep potential field gradients suggests that the fault positions are controlled by major lithologic contacts within the basement and that the faults may extend into the depth range where earthquakes are generated, revealing a potential link between specific faults and recently observed low-level seismicity in the area.

Illinois, Indiana, Kentucky↗