THE CURATED WELLS AND LOGS DATABASE (CWLDB): A NEW REPOSITORY TO IDENTIFY KEY WELLS AND PROVIDE SUBSURFACE DATA FOR FURTHER UNDERSTANDING U.S. GULF COAST BASIN ENERGY GEOLOGY

The U.S. Geological Survey (USGS) is building a new comprehensive well database for the U.S. Gulf Coast Basin to provide interpretive products for both future energy geology applications (e.g., carbon sequestration and energy storage), and ongoing oil and gas exploration and development. The Curated Wells and Logs Database (CWLDB) is an online repository currently being populated and already containing stratigraphic information for primarily petroleum wells in the U.S. onshore and State water portion of the Gulf of Mexico Basin (i.e., Texas, Louisiana, Mississippi, Alabama, and Florida). Key wells in the CWLDB provide several of the following attributes: a) deep penetration (generally, total depth of 10,000 feet or more), b) high resolution and diverse geophysical well log suites, c) lithostratigraphic columns, d) biostratigraphic interpretation (biozones) and reports, and e) drill core or cuttings samples.

One such well is Currie no. 1, a wildcat well drilled to a total depth of about 21,300 feet and located in St. Tammany Parish, southeast Louisiana. Using a geophysical well log suite (i.e., gamma ray, spontaneous potential, resistivity, and induction logs) to guide our interpretations, biostratigraphic (i.e., nannofossils) analyses of the drill cuttings were used to refine the location of formation tops and unconformities. New results include a better understanding of Lower Cretaceous through middle Miocene stratigraphy, identification of several major unconformities that were previously unrecognized, and an improved relation between formation tops and geophysical data.

The USGS Data Release for the CWLDB provides downloads of relevant formation top depths, biostratigraphically useful last occurrence datums and correlative biozones, a log ASCII (text) standard (i.e., LAS) file of the geophysical logs, and detailed photographs of all cuttings and/or cores, when available. The CWLDB is an ongoing project, which already contains interpretations and logs for an over 22,000-feet deep well (Foerster no. 1) in La Salle County, south Texas, and is expected to be updated with about a dozen additional wells as new interpretations are generated. Ultimately, this database is meant to expand the scope of USGS public-facing subsurface data and interpretation offerings related to energy geology and geophysics.