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Digital Stratigraphic and Structural Grids of the Cretaceous Lewis Shale in the Eastern Part of the Southwestern Wyoming Province, Wyoming and Colorado

November 3, 2023

This data release contains data associated with the Lewis Shale-Fox Hills Sandstone-Lance Formation depositional system (also referred to as the Lewis Shale system) in the eastern part of the Southwestern Wyoming Province of Wyoming and Colorado. Specifically, the data cover the Great Divide, Washakie, and Sand Wash Basins, the Wamsutter and Cherokee arches, and the Rock Springs Uplift. The Lewis Shale is underlain by the Almond Formation, overlain by the Fox Hills Sandstone, and interfingers with both formations on a regional scale. The Lewis Shale is divided into a lower, informal member, a middle, formal Dad Sandstone Member, and an upper, informal member. At the top of the lower Lewis member, there is a maximum flooding surface informally known as the Asquith marker. Additionally, within the Lewis Shale, there are 15 regional flooding surfaces (F01-F15) that bound and define 15 clinothems (C01-C15). Collectively, the data release includes 18 gross isopach grids, 15 net sand isopach grids, 2 structure grids, 1 data table, and 1 type log image of the Lewis Shale and associated strata. See the associated metadata files for the child data elements and the larger work of Hearon (in review) for detailed descriptions of the geology and additional methods.

Publication Year 2023
Title Digital Stratigraphic and Structural Grids of the Cretaceous Lewis Shale in the Eastern Part of the Southwestern Wyoming Province, Wyoming and Colorado
DOI 10.5066/P9NAFL9H
Authors Jane S Hearon
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Central Energy Resources Science Center