Paleomagnetic contributions to the Klamath Mountains terrane puzzle-a new piece from the Ironside Mountain batholith, northern California

Edward A. Mankinen; C. Sherman Gromme; W. Porter Irwin

doi:10.1016/j.tecto.2013.09.007

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Paleomagnetic contributions to the Klamath Mountains terrane puzzle-a new piece from the Ironside Mountain batholith, northern California

Edward A. Mankinen·C. Sherman Gromme·W. Porter Irwin

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Abstract

We obtained paleomagnetic samples from six sites within the Middle Jurassic Ironside Mountain batholith (~170 Ma), which constitutes the structurally lowest part of the Western Hayfork terrane, in the Klamath Mountains province of northern California and southern Oregon. Structural attitudes measured in the coeval Hayfork Bally Meta-andesite were used to correct paleomagnetic data from the batholith. Comparing the corrected paleomagnetic pole with a 170-Ma reference pole for North America indicates 73.5° ± 10.6° of clockwise rotation relative to the craton. Nearly one-half of this rotation may have occurred before the terrane accreted to the composite Klamath province at ~168 Ma. No latitudinal displacement of the batholith was detected.

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Source-reported bounding extent: 40.5° to 43° latitude; -124° to -122.5° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Edward A. Mankinen, C. Sherman Gromme, W. Porter Irwin. 2013. Paleomagnetic contributions to the Klamath Mountains terrane puzzle-a new piece from the Ironside Mountain batholith, northern California. https://doi.org/10.1016/j.tecto.2013.09.007

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