Igneous petrogenesis of magnesian metavolcanic rocks from the central Klamath Mountains, northern California

W. G. Ernst, B. R. Hacker, M. D. Barton, G. Sen

Research output: Contribution to journalArticle

26 Scopus citations

Abstract

Mafic meta-igneous supracrustal rocks in the east-central part of the western Triassic and Paleozoic belt are interlayered with and appear to predominantly overlie fine-grained clastic and cherty metasedimentary strata. This complex constitutes a lithostratigraphic terrane exposed in the vicinity of Sawyers Bar, California. Element proportions suggest that the dark, Ti + Fe* + P-rich basaltic lavas may have been extruded in an oceanic intraplate setting. Interstratification with distal turbiditic strata indicates concurrent submarine volcanism and deep-sea sedimentary deposition. The main mass of the stratigraphically higher extrusive sequence is a light-colored, massive tholeiite series, poorer in Ti + Fe* + P + LREE's. Hypabyssal rocks belong exclusively to this second igneous suite. Compositions of the pale-colored, overlying basaltic/diabasic mass of the Yellow Dog greenstone section are consistent with eruption in an immature magmatic arc. Yellow Dog igneous activity was extinguished during mid-Jurassic suturing of the oceanward Sawyers Bar terrane against and beneath the pre-existing landward Stuart Fork blueschist complex of Late Triassic metamorphic age. -from Authors

Original languageEnglish (US)
Pages (from-to)56-72
Number of pages17
JournalGeological Society of America Bulletin
Volume103
Issue number1
DOIs
StatePublished - Jan 1 1991
Externally publishedYes

ASJC Scopus subject areas

  • Geology

Fingerprint Dive into the research topics of 'Igneous petrogenesis of magnesian metavolcanic rocks from the central Klamath Mountains, northern California'. Together they form a unique fingerprint.

  • Cite this