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Geochemistry data for the USGS Gulf Coast #1 West Woodway core - A thermally immature core of the Eagle Ford Group in central Texas

June 18, 2019

Petroleum source rocks deposited during Cenomanian - Turonian time (late Cretaceous) are major generators of continuous and conventional oil and gas resources in the Gulf of Mexico Basin. The Eagle Ford Shale is a particularly important petroleum system and represents a substantial fraction of total oil and gas production in the United States. Significant lateral and vertical geochemical and mineralogical variability have been identified in previous studies of the Eagle Ford Shale, but most recent work has focused on the area of the play southwest of the San Marcos Arch. As part of a larger USGS coring program to examine important continuous oil and gas plays in the Texas-Gulf Coast region, the USGS Gulf Coast Petroleum Systems project drilled a thermally immature core near Waco, TX that recovered the Pepper Shale and the upper and lower Eagle Ford shale intervals (Eagle Ford Group). A combination of bulk organic and inorganic geochemistry and mineralogy along with molecular and isotopic analyses of rock extracts are presented and accompany a manuscript (French and others, 2019) that discusses organic matter source variability and depositional environment, as well as examining drivers of organic enrichment. Although a recent assessment of petroleum resources in southwest Texas associated with the Eagle Ford Shale was completed in 2018, many questions remain regarding the distribution of source rock organic facies and the nature of the Eagle Ford as an indigenous-continuous petroleum system, especially north of the San Marcos Arch. Ongoing research into these and other issues is vital for refining and updating geologic models for future assessments of these strata and also as a potential analog for other similar petroleum systems in the U.S. and around the world. This data set includes two spreadsheets. The first outlines the individual samples collected during the drilling activity. The second provides results from analyses performed and are grouped into High and Low resolution. Documentation on the methodology and the attributes are discussed in the entity and attribute section

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