Northern Alaska Range REE

Region Alaska, Alaska
Mineral systems
Deposit types
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Data-driven prospectivity ranking of watersheds (HUCs; Karl and others, 2016) shows that the focus area includes 35,720 km2 with a total of 76 high prospectivity HUCs and 163 medium prospectivity HUCs out of a total of 404 HUCs. This belt is defined principally on geochemical and lithologic grounds. Several of the clusters of HUCs in the belt are amongst the highest scored in the state, yet no known source for the geochemistry has been identified as ARDF occurrences are not reported in the belt.
Identified resources None.
Production None recorded.
Status Unknown.
Estimated resources Unknown.
Geologic maps Approximately 60% of the area has been mapped at 1:63,360 scale or better.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Lithology scores range from 0-1 with an average of 0.83. Igneous scores range from 0-4 with an average of 0.92.
Evidence from mineral occurrences No locations in ARDF contain REE mineralization.
Geochemical evidence Sediment scores range from 0-6, with an average of 4.26 for high HUCs.
Geophysical evidence Aeroradiometric scores range from 0-1 with an average of 0.58 points.
Evidence from other sources No data.
Comments This belt is primarily identified based on geochemical anomalies in sediment samples. The scores for the HUCs in this region range from 12.8-85% with an average of 50% of each HUCs score accrued from geochemistry.
Cover thickness and description Unknown.
Authors Douglas C. Kreiner, James V. Jones III, Melanie B. Werdon.
New data needs New geologic mapping, geophysical surveys and well-constrained geochemical sampling.
Geologic mapping and modeling needs Framework geology-includes lithology, structure, and hydrothermal alteration. Systematic detailed geologic mapping and bedrock sampling to identify sources of geochemical anomalies and to characterize igneous rock and their petrogenesis. Isotopic data (Hf, Pb) to test crustal character and terrane affinity.
Geophysical survey and modeling needs Rank 1 or 2 aeromagnetic data over the entire belt. Targeted EM where relevant for lithologic and structural mapping under cover.
Digital elevation data needs IfSAR coverage is complete over entire focus area.