This data release contains Rock-Eval pyrolysis, organic petrographic (reflectance), and X-ray diffraction mineralogy data for subsurface Mesozoic rock samples from the eastern onshore Gulf Coast Basin (primarily Mississippi and Louisiana). Samples were analyzed in support of the U.S. Geological Survey (USGS) assessment of undiscovered petroleum resources in the Upper Cretaceous Tuscaloosa marine shale and evaluation of shale gas prospectivity in the Aptian section of the Mississippi Salt Basin.

The U.S. Geological Survey assessed undiscovered petroleum resources in the downdip Paleogene formations of the U.S. Gulf Coast in 2018. During the assessment new data and information were collected to evaluate thermal maturity, source rock character, and unconventional reservoir rock prospectivity for the Cenozoic-aged section in south Louisiana. Samples were analyzed using multiple analytical approaches, including programmed pyrolysis (Rock-Eval), Leco TOC, organic petrographic analysis including vitrinite reflectance (Ro, %), and X-ray diffraction mineralogy.

The U.S. Geological Survey assessed undiscovered petroleum resources in the downdip Paleogene formations of the U.S. Gulf Coast in 2018. During the assessment new data and information were collected to evaluate thermal maturity, source rock character, and unconventional reservoir rock prospectivity for the Cenozoic-aged section in south Louisiana. Samples were analyzed using multiple analytical approaches, including programmed pyrolysis (Rock-Eval), Leco TOC, organic petrographic analysis including vitrinite reflectance (Ro, %), and X-ray diffraction mineralogy.

The USGS Gulf Coast Source Rock Database (GCSRD) is an online repository for all publicly available source rock data (outcrop and subsurface) from the states of Florida, Georgia, Alabama, Mississippi, Louisiana, Arkansas, and Texas. "Source rock data" are defined in this context as data that include any of the following measured or calculated parameters: -total organic carbon (TOC), -various pyrolysis measurements (Tmax, S1, S2, S3, HI, OI), -vitrinite or bitumen reflectance values. All data in the GCSRD have been extracted from previously published peer-reviewed literature or as USGS-released data sets; no new measurements are included. The underlying data set is presented as an interactive, map-view application where the user can filter by state, original publication, data type, age, or formation, which can be displayed and exported as needed. This release updates the initial (2021) GCSRD by adding 697 new entries to the initial data set.

The USGS Gulf Coast Source Rock Database (GCSRD) is an online repository for all publicly available source rock data (outcrop and subsurface) from the states of Florida, Georgia, Alabama, Mississippi, Louisiana, Arkansas, and Texas. "Source rock data" are defined in this context as data that include any of the following measured or calculated parameters: -total organic carbon (TOC), -various pyrolysis measurements (Tmax, S1, S2, S3, HI, OI), -vitrinite or bitumen reflectance values. All data in the GCSRD have been extracted from previously published peer-reviewed literature or as USGS-released data sets; no new measurements are included. The underlying data set is presented as an interactive, map-view application where the user can filter by state, original publication, data type, age, or formation, which can be displayed and exported as needed. This release updates the initial (2021) GCSRD by adding 697 new entries to the initial data set.

The USGS Gulf Coast Source Rock Database (GCSRD) is an online repository for all publicly available source rock data (outcrop and subsurface) from the states of Florida, Georgia, Alabama, Mississippi, Louisiana, Arkansas, and Texas. "Source rock data" are defined in this context as data that include any of the following measured or calculated parameters: -total organic carbon (TOC), -various pyrolysis measurements (Tmax, S1, S2, S3, HI, OI), -vitrinite or bitumen reflectance values. All data in the GCSRD have been extracted from previously published peer-reviewed literature or as USGS-released data sets; no new measurements are included. The underlying data set is presented as an interactive, map-view application where the user can filter by state, original publication, data type, age, or formation, which can be displayed and exported as needed. This release updates the initial (2021) GCSRD by adding 697 new entries to the initial data set.

This dataset captures in digital form the results of previously published U.S. Geological Survey (USGS) Water Mission Area studies related to water resource assessment of Cenozoic strata and unconsolidated deposits within the Mississippi Embayment and the Gulf Coastal Plain of the south-central United States. The data are from reports published from the late 1980s to the mid-1990s by the Gulf Coast Regional Aquifer-System Analysis (RASA) studies and in 2008 by the Mississippi Embayment Regional Aquifer Study (MERAS). These studies, and the data presented here, describe the geologic and hydrogeologic units of the Mississippi embayment, Texas coastal uplands, and the coastal lowlands aquifer systems, south-central United States. This dataset supercedes a previously released dataset on USGS ScienceBase (https://doi.org/10.5066/P9JOHHO6) that was found to contain errors. Following initial release of data, several types of errors were recognized in the well downhole stratigraphic data. Most of these errors were the result of unrecognized improper results in the optical character recognition conversion from the original source report. All downhole data have been thoroughly checked and corrected, data tables were revised, and new point feature classes were created for well location and WellHydrogeologicUnit. GIS data related to the geologic map and subsurface contours were correct in original release and are retained here in original form; only the well data have been revised from the initial data release. The Mississippi embayment, Texas coastal uplands, and coastal lowlands aquifer systems underlie about 487,000 km2 in parts of Alabama, Arkansas, Florida, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas from the Rio Grande on the west to the western part of Florida on the east. The previously published investigations divided the Cenozoic strata and unconsolidated deposits within the Mississippi Embayment and the Gulf Coastal Plain into 11 major geologic units, typically mapped at the group level, with several additional units at the formational level, which were aggregated into six hydrogeologic units within the Mississippi embayment and Texas coastal uplands and into five hydrogeologic units within the Coastal Lowlands aquifer system. These units include the Mississippi River Valley alluvial aquifer, Vicksburg-Jackson confining unit (contained within the Jackson Group), the upper Claiborne aquifer (contained within the Claiborne Group), the middle Claiborne confining unit (contained within the Claiborne Group), the middle Claiborne aquifer (contained within the Claiborne Group), the lower Claiborne confining unit (contained within the Claiborne Group), the lower Claiborne aquifer (contained within the Claiborne Group), the middle Wilcox aquifer (contained within the Wilcox Group), the lower Wilcox aquifer (contained within the Wilcox Group), and the Midway confining unit (contained within the Midway Group). This dataset includes structure contour and thickness data digitized from plates in two reports, borehole data compiled from two reports, and a geologic map digitized from a report plate. Structure contour and thickness maps of hydrogeologic units in the Mississippi Embayment and Texas coastal uplands had been previously digitized by a USGS study from georeferenced images of altitude and thickness contours in USGS Professional Paper 1416-B (Hosman and Weiss, 1991). These data, which were stored on the USGS Water Mission Area’s NSDI node, were downloaded, reformatted, and attributed for present dataset. Structure contour maps of geologic units in the Mississippi Embayment and Texas coastal uplands were digitized and attributed from georeferenced images of altitude and thickness contours in USGS Professional Paper 1416-G (Hosman, 1996) for this data release. Borehole data in this data release include data compiled for USGS Gulf Coast RASA studies in which a scanned version of a USGS report (Wilson and

The United States (US) Gulf Coast Basin Curated Wells and Logs Database (CWLDB) is an online repository with stratigraphic information for petroleum wells in the United States portion of the onshore US Gulf Coast Basin that provides several of the following attributes: a) deep penetrations (generally, total depth of 10,000 feet or more), b) high quality and diverse geophysical well log suites, c) lithostratigraphic logs, d) biostratigraphic units (biozones) and reports, and/or e) core or cuttings samples.