Trace elements in phosphatic shale, phosphoria formation, southeastern Idaho, USA

摘要

Rock units of the phosphate-producing Meade-peak Member of the Phosphoria Formation in southeastern Idaho show enhanced presence of several geoenvironmentally significant trace elements. The enrichments in the rocks of Cd, Cr, Cu, Hg, Mo, V, Zn and, especially, of Se, which already has exhibited some adverse effects following movement into the environment, creates concern about current mining, ore processing and, particularly, waste ore rock disposal techniques. Generally, deeper and less weathered ore zones have the greater element concentrations and other characteristics that likely enhance release of the trace elements into the environment. Current and planned research associated with this project will better define the content and forms of these trace elements in the rocks, along with their potential release into and interaction with the environment, and hopefully suggest better ways of handling ore and disposing of waste rock from mining.