Geologic mapping and critical minerals evaluation of the eastern pioneer mountains, southwestern montanaproject period: september 2025 september 2028PURPOSE:the primary objective of this study is to…

The U.S. Geological Survey awarded a cooperative agreement of $428,135 to Montana Technological University on February 16, 2026, under the Earth Mapping Resources Initiative (CFDA 15.073) for geologic mapping and critical minerals evaluation of the Eastern Pioneer Mountains in southwestern Montana.

The recipient will produce a 1:48,000-scale geologic map package for the study area with a GeoPDF, cross-sections, correlation charts, unit descriptions, and a GEMS Level 3 geodatabase consistent with STATEMAP deliverables. The project generates 200 whole-rock geochemical data points from fresh, altered, and mineralized rock samples, supplemented by mineralogical analysis, high-resolution sample imagery, SWIR spectral mineralogy data, SEM-TIMA datasets, LA-ICP-MS mineral chemistry data, and geochronology data. Detailed Anaconda-style alteration and mineralization maps at 1:12,000 scale will be produced for two to three focus areas. Deliverables also include a citable Montana Bureau of Mines and Geology publication summarizing primary scientific results related to critical commodity potential.

The project period runs from September 2025 through February 2029, with place of performance in Montana. Field work will occur primarily in summer and fall 2026 and 2027, with minor reconnaissance-level fieldwork in late 2025. Literature and map synthesis during the off-season will guide mapping activities. The project integrates existing geologic mapping at multiple scales with new geophysical data to refine understanding of mineral systems and link them to critical commodity occurrences in the region.

Geologic mapping and critical minerals evaluation of the eastern pioneer mountains, southwestern montanaproject period: september 2025 september 2028PURPOSE:the primary objective of this study is to use existing and new geologic mapping, geochemistry data, andnew earth MRI-funded geophysical data to refine the spatial and temporal understanding of mineralsystems in the eastern pioneers region and link these to critical commodity occurrences.activities to be performeda review of literature and maps will be conducted including existing 1:500K, 1:200K, 1:100K, 1:48K, AND1:24K mapping. Syntheses of previous work during the off-season will guide the mapping, which will beconducted primarily in the summer and fall months of 2026 and 2027, with minor reconnaissance-levelfieldwork in late 2025. Detailed anaconda-style alteration and mineralization maps (1:12,000-scale) willbe produced for 2-3 focus areas with appropriate occurrences of mineralization and alteration specificsites will be determined during the project. Geologic map compilation and sample processing will beginafter the 2025 field season.sampling of mineralization, alteration, and fresh intrusive volcanic rocks will generate 200 whole-rockgeochemical data points in addition to mineralogical data, high-resolution sample imagery, swir spectralmineralogy data, SEM-tima datasets, LA-ICP-MS mineral chemistry data, and geochronology data.deliverables geologic map package for the eastern pioneer mountains study area at 1:48K, including geopdfwith geologic elements that are consistent with statemap deliverables (cross-section, correlation chart, unit descriptions) and an associated gems level 3 format geodatabase. Whole-rock geochemical data 200 data points representing, fresh, altered, and mineralized rocksamples. Mbmg publication (citable) that provides a summary of the primary scientific results related tocritical commodity potential in the basin study area. Elements of this report will include:1. 2-3 detailed anaconda-style alteration and mineralization maps of prospects with locationand interpretation of any related geochemistry or geochronology data.2. Interpretations of mineral chemistry (SEM epma, LA-ICP-MS), alteration mineralogy(swir analysis), stable isotope analyses, and ground magnetic and radiometric data.3. Analysis of the results in the context of new high-resolution aeromagnetic and radiometricdata that covers the region.beneficiariesthis project intends to provide actionable data and information regarding the critical mineralsprospectivity of the region to the general public. Primary stakeholders include state and federal landmanagement agencies, local landowners, and the exploration mining industry. Geologic mapping andgeochemical sampling will also provide useful context for geohazards, groundwater, and geoenvironmentalinvestigations. This project also supports salaries for student field and lab assistants, whichprovides valuable research and training experience with a critical minerals project.