MINERAL RESOURCES OF THE WYOMING LANDSCAPE CONSERVATION INITIATIVE (WLCI) STUDY AREA—PAST, PRESENT, AND FUTURE
The world’s largest trona deposit (covering almost 3,600 km2), located in the southwestern part of WLCI, remains an economically viable commodity in today’s market. Uranium exploration was intense in the late 1950s into the 1970s, with activity in Ketchum Buttes, Poison Basin, Crooks Gap-Green Mountain, Shirley Basin, and Great Divide Basin. Today, the major mines in Crooks Gap-Green Mountain are either reclaimed or idle, Shirley Basin has been almost entirely reclaimed, and Ketchum Buttes appears abandoned, but there are proposed in-situ recovery projects being pursued in Great Divide Basin and Poison Basin.
Base- and precious-metals (gold, silver, copper, lead, zinc resources) are in the Lake Alice, Encampment, Seminoe, Iron Formation NE, Big Creek, Cooper Hill, Gold Hill, Herman, and Keystone mineralized areas. Most of these mineral “districts” were first explored and developed in the late 1800s and abandoned by the early 1900s. Some of them were re-explored or reactivated in the World War II era. Only a few were active in the 1970s to 1980s and nearly all have been abandoned. All the phosphate mines (such as at Leefe and South Mountain) and prospects in the western part of the study area appear to have been either abandoned or reclaimed.