Delta environments of the lower Chesterian (Mississippian) in Southern Illinois

Ope

Geographic Information System Approach for Play Portfolios to Improve Oil Production in the Illinois Basin

U.S. Department of Energy, DOE Award Number DE-FC26-02NT15132Ope

Subsurface structure and petroleum drilling in the Vincennes Quadrangle : Lawrence County, Illinios, and Knox Country Indiana

Ope

A Systems Approach to Identifying Exploration and Development Opportunities in the Illinois Basin: Digital Portifolio of Plays in Underexplored Lower Paleozoic Rocks

This study examined petroleum occurrence in Ordovician, Silurian and Devonian reservoirs in the Illinois Basin. Results from this project show that there is excellent potential for additional discovery of petroleum reservoirs in these formations. Numerous exploration targets and exploration strategies were identified that can be used to increase production from these underexplored strata. Some of the challenges to exploration of deeper strata include the lack of subsurface data, lack of understanding of regional facies changes, lack of understanding the role of diagenetic alteration in developing reservoir porosity and permeability, the shifting of structural closures with depth, overlooking potential producing horizons, and under utilization of 3D seismic techniques. This study has shown many areas are prospective for additional discoveries in lower Paleozoic strata in the Illinois Basin. This project implemented a systematic basin analysis approach that is expected to encourage exploration for petroleum in lower Paleozoic rocks of the Illinois Basin. The study has compiled and presented a broad base of information and knowledge needed by independent oil companies to pursue the development of exploration prospects in overlooked, deeper play horizons in the Illinois Basin. Available geologic data relevant for the exploration and development of petroleum reservoirs in the Illinois Basin was analyzed and assimilated into a coherent, easily accessible digital play portfolio. The primary focus of this project was on case studies of existing reservoirs in Devonian, Silurian, and Ordovician strata and the application of knowledge gained to future exploration and development in these underexplored strata of the Illinois Basin. In addition, a review of published reports and exploration in the New Albany Shale Group, a Devonian black shale source rock, in Illinois was completed due to the recent increased interest in Devonian black shales across the United States. The New Albany Shale is regarded as the source rock for petroleum in Silurian and younger strata in the Illinois Basin and has potential as a petroleum reservoir. Field studies of reservoirs in Devonian strata such as the Geneva Dolomite, Dutch Creek Sandstone and Grassy knob Chert suggest that there is much additional potential for expanding these plays beyond their current limits. These studies also suggest the potential for the discovery of additional plays using stratigraphic concepts to develop a subcrop play on the subkaskaskia unconformity boundary that separates lower Devonian strata from middle Devonian strata in portions of the basin. The lateral transition from Geneva Dolomite to Dutch Creek Sandstone also offers an avenue for developing exploration strategies in middle Devonian strata. Study of lower Devonian strata in the Sesser Oil Field and the region surrounding the field shows opportunities for development of a subcrop play where lower Devonian strata unconformably overlie Silurian strata. Field studies of Silurian reservoirs along the Sangamon Arch show that opportunities exist for overlooked pays in areas where wells do not penetrate deep enough to test all reservoir intervals in Niagaran rocks. Mapping of Silurian reservoirs in the Mt. Auburn trend along the Sangamon Arch shows that porous reservoir rock grades laterally to non-reservoir facies and several reservoir intervals may be encountered in the Silurian with numerous exploration wells testing only the uppermost reservoir intervals. Mapping of the Ordovician Trenton and shallower strata at Centralia Field show that the crest of the anticline shifted through geologic time. This study illustrates that the axes of anticlines may shift with depth and shallow structure maps may not accurately predict structurally favorable reservoir locations at depth

Geologic and engineering controls on Aux Vases sandstone reservoirs in Zeigler Field, Illinois : a comprehensive study of a well-managed oil field

"This report was prepared by the Illinois State Geological Survey as part of a project sponsored by the State of Illinois and the U.S. Department of Energy"--T.p. verso.Includes bibliographical references (p. 72-74)Co-funded by the USDOE and the State of Illinois, Department of Natural Resources. DE-FG22-89BC14250, AE-45Introduction -- Geologic setting -- Facies characteristics -- Regional setting for deposition of sand wave reservoirs -- Petrography and diagenesis -- Reservoir engineering

A core workshop and field trip guide book featuring the Aux Vases and Ste. Genevieve formations, April 4 and 5, 1986, SIU, Carbondale

Sponsored by Illinois Geological Society, Illinois State Geological Survey, and Southern Illinois University-CarbondaleOpe

Investigation of formation damage from mud cleanout acids and injection waters in Aux Vases sandstone reservoirs

Includes bibliographical references (p. 35-38)

The origin of prolific reservoirs in the Geneva Dolomite (Middle Devonian), West-Central Illinois Basin

Includes bibliographical references (p. 34-36)

Geochemical Interactions of Two Deep-Well Injected Wastes with Geological Formations: Long-Term Laboratory Studies

Two liquid hazardous wastes, an alkaline brinelike solution and a dilute acidic waste, were mixed with finely ground ??250 jlm) rock samples of three injection-related lithologies, sandstone, dolomite, and siltstone. The batch experiments were conducted for 155 to 230 days at 325??K and 10.8 MPa pressure. The pH and inorganic chemical composition of the alkaline waste were not significantly altered after 230 days of mixing. The acidic waste was neutralized by carbonate dissolution and transformed into a nonhazardous waste. Mixing the alkaline waste with the solid phases yielded several reaction products: brucite (Mg(OH)2)' calcite (CaC03), and possibly a sodium metasilicate. Claylike minerals formed in the sandstone; trace levels of hydrotalcite (M96AI2C03(OHh6'4H20) may have formed in the siltstone. Mixing the alkaline waste with a synthetic brine yielded brucite, calcite, and whewellite (CaC20 4??H20). The thermodynamic model PHROPITZ predicted that brucite and calcite would precipitate from solution in the dolomite and siltstone mixtures and in the alkaline waste-brine system. After 155 days of solid-liquid contact, the dilute acidic waste had not significantly altered the mineralogical composition of any of the three rock types. The model PHREEOE indicated that calcite was thermodynamically stable in the dolomite and siltstone mixtures, and it was detected in small quantities in the aged-solid samples. The sandstone-waste system appeared to equilibrate with amorphous silica, whereas silica equilibria may not have been attained in the dolomite and siltstone systems. Computer models like PHROPITZ and PHREEOE may be useful tools for estimating mineral equilibria in deep-well scenarios, but there is a need to expand the database used in these kinds of calculations. The predicted equilibria must be interpreted with caution.Illinois Hazardous Waste Research and Information Center; Project # HWRIC 88-066published or submitted for publicationis peer reviewe

Sedimentology and reservoir characterization of the Silurian carbonates in the Mt. Auburn Trend of the Sangamon Arch, West-Central Illinois

Ope