Title | Sylvan Lake and granite spires in the winter, Black Hills, South Dakota |
Description | The core of the Black Hills is composed of 1.7 billion year old granite that intruded a Pre-Cambrian schist. The tough Harney Peak Granite has resisted weathering and is exposed in many places. It forms Mt. Rushmore, other (uncarved) domes and in some places has weathered into spires and needles. This view shows (frozen) Sylvan Lake with granitic spires behind. Sylvan Lake is an artificial lake in Custer State Park, along the Needles Highway, just east of Custer, South Dakota. |
Chronostratigraphy | Precambrian |
Lithostratigraphy | Harney Peak Granite |
Geologic province | Black Hill |
Location | USA ▹ South Dakota ▹ Pennington. Near Rapid City. |
Photographer | Dexter Perkins. 2002-02-20. |
Key words | granite, Sylvan Lake, Black Hills, South Dakota |
Tech details | 535 KB. Vista. Canon A1, Agfachrome 100. |
GeoDIL number | 2395 |
|