Critical Minerals in Pennsylvanian Black Shales in Indiana

Status Start Date End Date Locations
Active Jan 10, 2023 Jan 9, 2026 All Counties
Director: Maria Mastalerz
Other Researchers: Isaac Allred, Philip Ames, Ashley Douds, LaBraun Hampton, Jennifer Lanman, Katherine Tucker
Funding: U.S. Geological Survey (USGS) - - USGS - No Specific Program
Issue: Available data on Pennsylvanian black shales suggest that they are often enriched in various metals and can be enriched in rare earth elements. Although Pennsylvanian black shales have been of geologic interest over a century, only a handful of localized studies provide good quality geochemical data on critical mineral and REE potential of these shale units. Consequently, due to a lack of robust data, it is not possible to precisely quantify the economic potential of these resources. This multi-state project aims to expand a geochemical database of Pennsylvanian black shales in the United States.
Objective: The objective of this project is to expand our database on critical elements in the Pennsylvanian black shales
Approach: The project will begin with identification of available cores containing Pennsylvanian black shale horizons. This activity will be guided by our recent studies of black shales that already sampled 11 locations (Fig. 1) and identified basic characteristics of black shales (Mastalerz et al., 2022). We plan to select approximately 15 cores in addition to those 11 already analyzed. Core selection will take into account stratigraphic distribution, so that black shales of both Carbondale and Raccoon Creek Groups will be well represented. In total, we plan to collect about 300 samples of black shales. The number of samples from individual black shale horizons will depend on the shale thickness. In addition to shales, associated lithologies may also be sampled for comparative purposes. We plan to begin sampling in March 2023, after careful selection and analysis of the available cores. We will analyze all samples by pXRF before sending them to the United States Geological Survey (USGS) for detailed analysis. These analyses will be compared to the previously obtained pXRF data on black shales from other locations (Mastalerz et al., 2019; Mastalerz et al., 2020; Mastalerz et al., 2022). Splits of all samples will be retained at the IGWS for in-house analysis including but not limited to carbon sulfur and vitrinite reflectance. References: Mastalerz, M., Cortland, E., Drobniak, A. Ames, P.R., and McLaughlin, P., 2020, Rare earth elements and yttrium in Pennsylvanian coals and shales in the eastern part of the Illinois Basin, International Journal of Coal Geology 231, 103620. doi: 10.1016/j.coal.2020.103620 Mastalerz, M., Drobniak, A., and Ames, P., 2022, Organic-matter-rich Pennsylvanian black shales as a source of critical minerals: Indiana Geological and Water Survey, Indiana Journal of Earth Sciences v. 4. doi:10.14434/ijes.v4i1.34421 Mastalerz, M., Drobniak, A., Ames, P., and McLaughlin, P.I., 2019, Application of pXRF elemental analysis in Pennsylvanian coal-bearing strata—an example from the Indiana part of the Illinois Basin: International Journal of Coal Geology 216, 103342. doi: 10.1016/j.coal.2019.103342
Products: These newly-obtained data will be added to the existing database of the Pennsylvanian black shales in Indiana, and will be summarized in the final report and the resultant publications.
Benefits: This multi-state project will expand a geochemical database of Pennsylvanian black shales in the United States, with a special emphasis on critical minerals.