Unnamed (east of Eagle Creek)
Unnamed (east of Eagle Creek) is a rare earth occurrence in Alaska, recorded in the USGS USMIN rare earth element occurrence database (ver. 4.0, June 2019).
Location: Alaska, United States
Commodities: rare earth elements; thorium; uranium
Deposit model: unclassified
Geology
The mineralized rock consists of medium- to coarse-grained syenite characterized by large (as much as 1.25 cm or 0.5 in) brownish-black allanite crystals constituting 20 to 40 percent of the rock. Because of extensive frost-heaving, none of the allanite-rich rock can be found actually in place; however, abundant pieces of float of this material as much as 30 cm (12 in) across occur scattered over a zone 9-14 m (30-45 ft) wide and extending some 60 m (200 ft) across the top of the knoll. Syenite of the Kachauik pluton (Miller and others, 1972; Miller, 1972; Till and others, 1986) is anomalously radioactive adjacent to crosscutting alkaline dikes (Miller and others, 1976) here. The Kachauik pluton is a composite syenite, monzonite, granodiorite, quartz monzonite body that is mid-Cretaceous in age; a K/Ar age for the Kachauik pluton is 86.1 +/- 3 Ma (Miller and others, 1972). (Miller and others (1976))
Sources
- U.S. Geological Survey · published Jun 1, 2019 · retrieved Aug 12, 2026 · archive unavailable: Wayback snapshot 20260427015518 of the ScienceBase item exists but the archive service returned 503 on verification 2026-08-12; recheck on a weekly pass