Preliminary Investigation of Rare-Earth-Element-Bearing Veins, Breccias, andCarbonatites in the Laughlin Peak Area, Colfax County, New Mexico

摘要

In 1989, the U.S. Bureau of Mines conducted a preliminary field investigation toevaluate the rare-earth and associated element resources in the Laughlin Peak area, Colfax County, New Mexico. Bureau personnel mapped and sampled prospects and mineralized zones, and conducted a site-specific geochemical survey to appraise the mineral resources and identify localities favorable for resources. Fifty-eight samples were taken primarily from rare-earth-element-bearing veins, intrusive breccias, and carbonatites. No identified resources were estimated at the surface due to limited data because of soil and colluvial cover; however, a previously unreported small rare-earth-element-bearing plug-like body of magnesiocarbonatite and a 4,000-ft-long silicified carbonatite dike were identified. The presence of rare-earth-element-bearing carbonatites in association with widely distributed rare-earth-element-bearing veins and intrusive breccias suggests that this is the upper part of a carbonatite complex. High rare-earth-element concentrations found in the magnesiocarbonatite plug and enriched rare-earth-element concentrations in the surrounding intrusive breccias suggest that resources of rare-earth-elements could be present at depth and outline a target locality for exploration.