MINERAL RESOURCES OF THE ENCAMPMENT COPPER REGION, 
WYOMING. 
By Arthur C. Spencer. 
INTRODUCTION. 
The town of Encampment is situated 43 miles by wagon road south 
of Wolcott station on the Union Pacific Railroad, in Carbon County, 
Wyo., in the foothills of the Park Range, which constitutes the conti- 
nental divide and is localty known as the Sierra Madre. 
The Encampment Special quadrangle occupies the area between 
latitudes 41° and 41° 15' north and longitudes 106° 15' and 107° 15' 
west, and includes the town of Encampment in its northeast corner. 
The greater portion of the area, which has an extent of about 450 
square miles, lies within the State of Wyoming, but a narrow strip of 
Colorado is included upon the south. 
In a more extended report now in preparation a statement of the 
several classes of ore deposits observed will be given, together with a 
general discussion of the conditions of ore deposition in the region. 
GENERAL GEOLOGY. 
The geology of the Encampment region, when studied in detail, is 
found to be very intricate, but the more general features can never- 
theless be readily outlined and as readily perceived upon the ground. 
Among the most prominent features presented by the region are 
certain bands of white quartzite, which the visitor first notes a few 
miles southwest of the town of Encampment on the road to Battle. 
The bands or reefs of quartzite, which cross the country in a nearly: 
east-west direction, are separated from one another sometimes by bands 
of conglomerate, slate, and limestone, and in other cases by dikes 
of dark diorite. All of these formations have a general dip toward 
the south, and frequently stand at steep angles. Taken together, the}' 
occupied a narrow wedge-shaped area, extending for a distance of 
about 20 miles westward from its point or apex below the mouth 
of Purgatory Gulch on the Encampment River, a few miles south oi 
Encampment town site. The widest part of the quartzite area id 
upon the west, where it becomes covered by surface formations ii 
the drainage of Big Sandstone Creek and of Savery River. With thd 
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