Preliminary Geologic Map of the Red Ridge Area, Churchill and Mineral Counties, Nevada
Author: Chad W. Carlson
Series: Open-File Report 2017-02
Format: plate: 35.5 x 28 inches, color; text: 7 pages, color
Free download/purchase: http://pubs.nbmg.unr.edu/Prel-geol-Red-Ridge-area-p/of2017-02.htm
The Walker Lane accommodates dextral motion between the northwest translating Sierra Nevada microplate to the west and Basin and Range extension to the east. A significant portion of dextral shear in the central Walker Lane is accommodated on left-stepping, en echelon, northwest-striking fault systems that compose the Walker Lake domain. Northwest of these dextral faults, strain is transferred to sinistral faults accommodating oroclinal flexure and clockwise-rotation of blocks in the Carson domain of the northern Walker Lane. Positioned at the northern terminus of the Walker Lake domain, the Red Ridge area resides southeast and in right-lateral separation across the Benton Spring fault from the Terrill Mountains. The thick Oligocene to late Miocene volcanic strata of the Red Ridge area provide opportunity to examine Tertiary strata and styles of deformation and correlate to results of recent geologic mapping completed in the adjacent Terrill Mountains quadrangle. Detailed geologic mapping of the Red Ridge area was completed to help elucidate the Neogene styles of, and transitions in, strain accommodation for this region of the Walker Lane.
Geologic mapping of the Red Ridge area greatly elucidated the stratigraphic and structural framework of Red Ridge and expanded understanding of deformation at the northern termination of the Walker Lake domain. The Tertiary strata included late Oligocene ash-flow tuffs and Miocene volcanic rocks correlated to, and dextrally offset from, Terrill Mountains stratigraphy. Several ash-flow tuffs correlate with regionally extensive units and provide opportunity for future paleomagnetic study. Similar to the southern Terrill Mountains, northeasterly-striking normal faults appear kinematically linked to major northwest-striking dextral faults and accommodate diffusion of dextral strain and basin development. The detailed mapping of the Red Ridge area has provided a firm foundation for future structural analysis and paleomagnetic study of the region.
This map was partially funded by the National Science Foundation.