Grass Range

Region West, Northwest
States
Mineral systems
Deposit types
Commodities
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Kimberlite and lamprophyre diatremes with possible carbonatite and REE-enrichment.
Identified resources None.
Production None.
Status A kimberlite diatreme called the Homestead Kimberlite was explored as a possible diamond resource in 1999.
Estimated resources Unknown.
Geologic maps Porter and Wilde (1999); scale 1:100,000.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Lamprophyre and kimberlite diatremes.
Deposits None.
Evidence from mineral occurrences Regional association of lamprophyre breccias and REE mineralization.
Geochemical evidence There is no known geochemical evidence for the occurrence of critical elements.
Geophysical evidence Unknown.
Evidence from other sources Unknown.
Comments Lamprophyres in the region are known to have occurrences of Ti and Cr in other districts and could be enriched in REE. Possible kimberlite-carbonatite association. Enrichment for critical minerals is inferred as there is little information from these rocks.
Cover thickness and description Surficial.
Authors Stanley L. Korzeb, Kaleb C. Scarberry, Jay A. Gunderson, Joshua M. Rosera, Allen K. Andersen.
New data needs High resolution geophysics, whole-rock geochemistry for all critical minerals, geologic mapping, lidar.
Geologic mapping and modeling needs Targeted 1:24,000 or 1:12,000 scale geologic mapping would improve understanding of geologic controls on distribution of commodities.
Geophysical survey and modeling needs High resolution airborne surveys where magmatic unconformities are suspected.
Digital elevation data needs Lidar inadequate.