EARTH MRI ACTIVITIES AT THE KENTUCKY GEOLOGICAL SURVEY

The Kentucky Geological Survey participates in the USGS Earth MRI program to support critical minerals research in Kentucky. KGS has a >150yr history of minerals research and publications, including a large archive of minerals reports and data, available through the KGS web service. A complete set of published and digitized 1:24,000-scale USGS Geologic Quadrangle maps are also available for KGS to use to better understand areas of known critical minerals in the state, as well as to identify new areas with critical minerals potential.

Currently, KGS is collaborating with USGS and the Illinois State Geological Survey to examine the Hicks Dome Igneous Complex and the adjacent Illinois–Kentucky Fluorspar District in southern Illinois and western Kentucky. Hicks Dome is a concealed carbonatite intrusion, and the surrounding district has numerous mapped exposures of generally north-northwest trending ultramafic igneous dikes. The area is complexly faulted and extensive fluorspar mineralization is typically associated with the northeast trending faults. KGS is compiling 1:24,000-scale geologic map data and associated mineral occurrence information for the area, updating catalogs of >200 rock cores in the KGS Earth Analysis Research Library inventory, and assembling available cross sections to support a 3D conceptual model of igneous and mineral features in the Kentucky portion of the district. Beyond Kentucky, Illinois and USGS are compiling geologic maps, mineral occurrence data, and coordinating and interpreting high-resolution aerial magnetics and radiometric data. All three agencies will collaborate to generate seamless regional maps of the district.

KGS participated in the October 2019 Eastern and Central US Earth MRI Planning Workshop to work with USGS and other state geological surveys to identify and prioritize future focus areas for the program. Kentucky collaborated with multiple states to prepare Earth MRI Focus Area prospectuses targeting central US Devonian black shales and Pennsylvanian underclays for their REE and other critical mineral potential. To prepare for and inform possible future Earth MRI projects in these and other areas, KGS is collecting new modern geochemistry and compiling available published data on critical mineral occurrences and prospects in Kentucky.