Paleomagnetic study of some Cretaceous and Tertiary sedimentary rocks of the Klamath Mountains province, California.

Paleomagnetic investigation of Cretaceous outliers and Tertiary sedimentary strata of the Klamath Mountains province, and of onlapping Cretaceous strata, has shown the rocks to be largely remagnetized. Samples studied are from the Upper Jurassic to Upper Cretaceous Great Valley sequence, Upper Cretaceous Hornbrook Formation, Eocene Montgomery Creek Formation, and Oligocene(?) Weaverville Formation. Cretaceous samples that survived the remagnetization have a mean remanence direction that is very close to the expected direction of the Cretaceous magnetic field at the locality of the Klamath Mountains. Data from both primary and remanetized samples suggest the possiblity of 11.5o+ or -15.8o of post-Cretaceous clockwise rotation of the Klamath Mountains province. -Authors