Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cashman, S. M. Articles by Elder, D. R. Search for Related Content GeoRef GeoRef Citation

Post-Nevadan detachment faulting in the Klamath Mountains, California

Susan M. Cashman^,1 and Don R. Elder^,2

¹ Department of Geology, Humboldt State University, Arcata, California 95521, USA
² Klamath National Forest, 1312 Fairlane Road, Yreka, California 96097, USA

A group of faults surrounding the Trinity terrane in the core of the Klamath Mountains province of northern California displays a commonality in physical features and in age that sets them apart from other faults in the Klamath Mountains. The faults dip shallowly outward from the central Trinity terrane and feature younger-on-older, detachment-fault geometry. Several exhibit shallowly south-southwest– or south-southeast–plunging slickenside striations. Distinctive muscovite-bearing dacite, muscovite-bearing rhyolite, and plagioclase porphyry dikes are common along these faults, as are epithermal mineralization and associated small, but economic gold and/or copper massive-sulfide deposits. Two of the faults crosscut the Triassic Siskiyou thrust. In addition, the Cecilville fault cuts the Late Jurassic Soap Creek Ridge fault, so extensional faulting postdates the widely developed Nevadan deformational event in the Klamath Mountains. A 126 ± 3 Ma K- Ar whole-rock age obtained on a muscovite-bearing rhyolite dike intruding the fault zone at Menzel Gulch, on the southern margin of the Trinity terrane, gives a minimum age of Early Cretaceous for this fault. Evidence for Tertiary extensional faulting on the La Grange fault, previously reported by Schweickert and Irwin, records a later episode of extension on the southern margin of the Trinity terrane.

Key Words: detachment fault • extension tectonics • faults and faulting • Klamath Mountains • massive-sulfide deposits

This article has been cited by other articles:

				S. M. Cashman and K. V. Cashman Cataclastic textures in La Grange fault rocks, Klamath Mountains, California Geological Society of America Special Papers, January 1, 2006; 410(0): 433 - 450. [Abstract] [Full Text] [PDF]