Mesozoic petrotectonic development of the Sawyers Bar suprasubduction-zone arc, central Klamath Mountains, northern California
The Sawyers Bar area of the central Klamath Mountains, California, consists of three tectonically juxtaposed supracrustal units: (1) on the east, the Stuart Fork metabasalt-metachert-metagraywacke terrane above the low-angle, east-dipping Soap Creek Ridge thrust; (2) the medial North Fork ophiolitic terrane, composed of intercalated St. Clair Creek laminated cherts and fine-grained quartzofeldspathic argillites, interstratified with and overlain by two mafic igneous, largely extrusive suites--North Fork (sensu stricto) mildly alkaline basalts, and Salmon River basaltic-diabasic-gabbroic arc tholeiites; and (3) the cherty, Eastern Hayfork metagraywacke melange terrane west of the minor, high-angle Twin Sisters fault. Mineral and bulk-rich elemental and isotopic data, integrated with geologic mapping, document deformation and fluid-rock interaction in the upper few kilometers of a suprasubduction-zone basaltic arc during tectonic accretion to the western margin of North America or a nearby offshore arc. The geologic history is advanced.
- Research Organization:
- Stanford Univ., CA (US)
- Sponsoring Organization:
- US Department of Energy
- DOE Contract Number:
- FG03-90ER14154
- OSTI ID:
- 20000544
- Journal Information:
- Geological Society of America, Bulletin, Journal Name: Geological Society of America, Bulletin Journal Issue: 8 Vol. 111; ISSN 0016-7606; ISSN BUGMAF
- Country of Publication:
- United States
- Language:
- English
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