New geologic map: Heath Canyon, central Grant Range, Nye County

Open-File Report 14-6

Preliminary geologic map of Heath Canyon, central Grant Range, Nye County, Nevada, by Sean P. Long, 2014


New 1:24,000-scale mapping across the full width of the central Grant Range, in a transect-style map located east of the Grant Canyon and Bacon Flat oil fields in Railroad Valley, provides valuable context for relating the structural style and geometry within the range to the subsurface structure of the oil fields.  Sedimentary rocks between Cambrian and Pennsylvanian in age, and Eocene to Oligocene sedimentary and volcanic rocks, are exposed in the map area.  Cambrian and Ordovician rocks have been metamorphosed to greenschist facies and experienced penetrative ductile deformation, likely during the Cretaceous.  Two separate sets of normal faults deform the section, including an older set of down-to-the-west detachment faults that eliminate stratigraphy, and formed at low angles to bedding, and a younger set of high-angle, cross-cutting normal faults, including a range-bounding fault with multiple Holocene surface ruptures.  Several detachment faults cut Oligocene volcanic rocks, providing a maximum age bound for the older episode of extension.

This publication was prepared as part of the STATEMAP component of the National Cooperative Geologic Mapping Program in cooperation with the U.S. Geological Survey.

Open-File Report 14-6, scale 1:24,000, 41 x 26 inches, color; 4-page text, b/w; folded or rolled, $16.00 for paper copy–or free on the Web:

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