Comparative studies of jurassic, cretaceous, and cenozoic carbonate replacement deposits and related carbonate-hosted mineralization, arizona borderlandsproject period: 02 01 2026 through 01 31…

The U.S. Geological Survey awarded the University of Arizona (operating as Arizona Board of Regents) a cooperative agreement totaling $482,195 on February 1, 2026, under the Earth Mapping Resources Initiative (CFDA 15.073) to conduct comparative studies of Jurassic, Cretaceous, and Cenozoic carbonate replacement deposits and related carbonate-hosted mineralization in the Arizona Borderlands.

The University of Arizona will investigate the critical mineral potential of carbonate-hosted mineral deposits across southeastern Arizona at regional and district scales. The work focuses on carbonate replacement deposits (CRDs) at Tombstone and Courtland-Gleeson, which host high-grade, sulfide-rich, polymetallic systems in Paleozoic carbonates. The recipient will conduct deposit-scale analytical work examining mineralization relationships to potential porphyry systems and characterize polymetallic and skarn deposits containing non-critical ores (copper, cadmium, molybdenum, lead, silver, gold) and critical ores (zinc, manganese) with potential enrichment in germanium, gallium, indium, bismuth, antimony, scandium, arsenic, tungsten, and tellurium. A portion of the funding will augment ongoing Earth MRI work on Proterozoic mineralization in northwestern Arizona.

The period of performance runs from February 1, 2026, through January 31, 2029. Work is performed in Arizona.

Comparative studies of jurassic, cretaceous, and cenozoic carbonate replacement deposits and related carbonate-hosted mineralization, arizona borderlandsproject period: 02 01 2026 through 01 31 2029PURPOSETHE arizona geological survey (azgs) proposes to investigate the critical mineral potential of carbonate-hosted mineral deposits (with a deposit-scale study on carbonate replacement deposits) in southeastern arizona. Southeastern arizona is host to several known carbonate replacement deposits (crds) that are often high-grade, sulfide-rich, polymetallic systems hosted in paleozoic carbonates. The host stratigraphy for CRD mineralization varies, with CRD mineralization at tombstone hosted within paleozoic limestones (with high-grade and oxidized mantos also hosted in the bisbee group), and CRD mineralization largely hosted within the abrigo formation at the courtland-gleeson area. While each area has known intrusions of jurassic and or cretaceous to early paleogene ( laramide ) age that can serve as the potential source for hydrothennal fluids, open questions remain as to whether the CRD mineralization at each locale is related to a porphyry system, with no known (but ongoing exploration taking place) porphyry systems identified at tombstone, and at least one jurassic porphyry system (and potentially a laramide porphyry system) at courtland-gleeson. Polymetallic carbonate replacement and skarn deposits can have non-critical ores of CU-CD-MO-PB-AG-AU, as well as critical ores of ZN-MN, with additional potential for critical element enrichment of GE, GA, in, BI, SB, SC, as, w, and TE. This critical mineral potential will be investigated thoroughly at both regional (southern arizona) and district (courtland-gleeson) scales. Additionally, a portion of the funding will be allocated to augment ongoing earth MRI work on proterozoic mineralization in northwestern arizona.activities to be performedazgs proposes a three-year project focused on analytical work in addition to collecting samples for whole-rock geochemistry. In year 1, the principal aim will be: 1) compilation of existing data, 2) sample collection from mineral deposits from legacy collections and accessible public lands 3) initiate conversations and develop relationships with mining companies and holders of private property to obtain sampling access and 4) begin sample characterization (petrography, stained slabs). Sample collection (including private property samples) and characterization (expanding to include mineral isotope chemistry, GEO thermochronology, and SEM epma work) will continue into years 2 and 3. In year 3, azgs will finalize sample characterization, compilation of new and legacy data into a uniform geochemical database with supporting datasets, and write a report providing a regional assessment of the geochemical prospectively of the carbonate-hosted mineral deposits of arizona and identify prospects and prospects that have elevated critical mineral potential.DELIVERABLES1.compilation geochemical database, with accompanying datasets, of carbonate-hosted prospects and mineral deposits in arizona (including legacy, published data) AND2.comprehensive summary report providing a regional assessment based on compiled and new analytical data.beneficiariesazgs products are used by numerous stakeholders, including decision policymakers, professional geologists in engineering, environmental, and minerals geology, student and academic geologists, and members of the public interested in their local geology. The recipient anticipate the products from this project being particularly useful to exploration geologists and researchers working on the genesis of critical mineral-bearing deposits in arizona.