October 20, 2004
State Survey Completes Saratoga Geologic Map
The Wyoming State Geological Survey (WSGS) has released a new geologic map that encompasses major parts of the Medicine Bow Mountains and the Sierra Madre, including the towns of Centennial, Saratoga, and Encampment. WSGS geologists Wayne M. Sutherland and W. Dan Hausel compiled the new map, which is entitled Preliminary geologic map of the Saratoga 1:100,000-scale Quadrangle, Albany and Carbon counties, Wyoming. The project was funded in part through grants from the U.S. Geological Surveys STATEMAP program.
The map was compiled from available geologic maps, aerial photograph interpretation, and reconnaissance field mapping where required. The Medicine Bow Mountains and Sierra Madre of southeastern Wyoming are Precambrian-cored uplifts that contain rocks ranging in age from Precambrian to Quaternary. These mountain ranges are cut by the Cheyenne Belt, a major geologic break between the older Precambrian Wyoming Province (Wyoming craton) to the north and the younger Precambrian Colorado Province to the south.
The new map incorporates localized areas of interest for some strategic metals and minerals including gold, platinum-group metals, chromite, titanium, vanadium, copper, diamond, other gemstones, and rare earth metals. Large blocks of ground surrounding the Mullen Creek, Lake Owen, and Puzzler Hill mafic and ultramafic complexes within the map area have recently received considerable interest for platinum-group metals. Increased gold and platinum prices make the quadrangle especially interesting. The search for rare earth metals in the Big Creek district has also gained momentum during the past few years. The quadrangle has high potential for the discovery of significant gem and industrial diamond deposits.
The map area includes several historical mining districts including Gold Hill, Grand Encampment, Keystone, Douglas Creek, New Rambler, Big Creek and others; hundreds of historical mines and prospects lie within the map area. Some areas within the Saratoga 1:100,000 are also of interest for oil and gas, groundwater, road-bed material (sand and gravel), and other base and precious metals, as well as for forestry, ranching, and recreational interests (hiking, hobby prospecting, fishing, skiing, hunting, etc.). A major part of the Medicine Bow National Forest lies within the area.
Open File Report OFR 04-10 is available at the WSGS office in Laramie or by mail. The map is available as one black and white (uncolored) map (rolled only) for $20.00, or as a set of three colored maps (rolled only) for $35.00. The map includes a 34-page report. For mail orders include $6.00 postage and handling; Wyoming addresses or purchases over the counter should also include 6% sales tax.
from the Office of the Wyoming State Geologist
Ron Surdam, State Geologist