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Title: Petroleum potential of the Upper Ordovician Maquoketa Group in Illinois: A coordinated geological and geochemical study

Petroleum potential of the Upper Ordovician Maquoketa Group in Illinois: A coordinated geological and geochemical study The Ordovician Maquoketa Group in Illinois, predominantly composed of shale, calcareous shale, and carbonates, has long been considered a potential source for Illinois basin hydrocarbons. Methods used to better define the petroleum potential of the Maquoketa in the Illinois basin were lithostratigraphic study, Rock-Eval (pyrolysis) analyses, comparison of molecular markers from whole-rock extracts and produced oil, and construction of burial history models. Organic-rich submature Maquoketa potential source rocks are present in western Illinois at shallow depths on the basin flank. Deeper in the basin in southern Illinois, Rock-Eval analyses indicate that the Maquoketa shale is within the oil window. Solvent extracts of the Maquoketa from western Illinois closely resemble the Devonian New Albany Shale, suggesting that past studies may have erroneously attributed Maquoketa-generated petroleum to a New Albany source or failed to identify mixed source oils. Subtle differences between Maquoketa and New Albany solvent extracts include differences in pristane/phytane ratios, proportions of steroids, and distribution of dimethyldibenzothiophene isomers. Maquoketa solvent extracts show little resemblance to Middle Ordovician oils from the Illinois or Michigan basins. Lithostratigraphic studies identified localized thick carbonate facies in the Maquoketa, suggesting depositional response to upper Ordovician paleostructures. Sandstone facies in the Maquoketa in southwestern Illinois offer more » a potential source/trap play, as well as serving as potential carrier beds for hydrocarbon migration. Maquoketa source and carrier beds may feed older Ordovician rocks in faulted areas along and south of the Cottage Grove fault system in southern Illinois. « less
Authors: ; ;
Publication Date:
OSTI Identifier:6857460
Report Number(s):CONF-900605--
Journal ID: ISSN 0149-1423; CODEN: AABUD
Resource Type:Conference
Resource Relation:Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA); Journal Volume: 74:5; Conference: Annual convention and exposition of the American Association of Petroleum Geologists, San Francisco, CA (USA), 3-6 Jun 1990
Country of Publication:United States
Language:English
Subject: 02 PETROLEUM; 58 GEOSCIENCES; ILLINOIS; PETROLEUM DEPOSITS; EXPLORATION; BLACK SHALES; CARBONATE ROCKS; GEOCHEMICAL SURVEYS; GEOLOGIC FAULTS; GEOLOGIC FORMATIONS; GEOLOGIC SURVEYS; LITHOLOGY; ORDOVICIAN PERIOD; PYROLYSIS; RESOURCE POTENTIAL; SEDIMENTARY BASINS; SOURCE ROCKS; STRATIGRAPHY; BITUMINOUS MATERIALS; CARBONACEOUS MATERIALS; CHATTANOOGA FORMATION; CHEMICAL REACTIONS; DECOMPOSITION; ENERGY SOURCES; FEDERAL REGION V; FOSSIL FUELS; FUELS; GEOLOGIC AGES; GEOLOGIC DEPOSITS; GEOLOGIC FRACTURES; GEOLOGIC STRUCTURES; GEOLOGY; MATERIALS; MINERAL RESOURCES; NORTH AMERICA; OIL SHALES; PALEOZOIC ERA; RESOURCES; ROCKS; SEDIMENTARY ROCKS; SURVEYS; THERMOCHEMICAL PROCESSES; USA 020200* -- Petroleum-- Reserves, Geology, & Exploration; 580000 -- Geosciences