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Publications

National Laboratories Program publications.

Filter Total Items: 1080

Thermal maturity of tectonostratigraphic terranes within the Franciscan Complex, California Thermal maturity of tectonostratigraphic terranes within the Franciscan Complex, California

Indicators of organic metamorphism provide valuable tools for analyzing the thermal history of tectonostratigraphic terranes. Paleotemperature estimates derived from vitrinite reflectance, for example, are more precise than values based upon inorganic mineral assemblages in low‐grade rocks. Isothermal geometries must be interpreted within the context of structural and stratigraphic data...
Authors
M.B. Underwood, M. Blake, D. Howell

Remagnetization of the Coast Range Ophiolite and Lower Part of the Great Valley Sequence in Northern California and Southwest Oregon Remagnetization of the Coast Range Ophiolite and Lower Part of the Great Valley Sequence in Northern California and Southwest Oregon

Overprinted magnetizations have been found at four localities in the Middle Jurassic Coast Range ophiolite and the overlying Upper Jurassic and Lower Cretaceous Great Valley sequence in northern California and at one locality in the partially correlative Lower Cretaceous Days Creek Formation in southwest Oregon. At Del Puerto Canyon, on the east side of the Diablo Range, a pilot study of...
Authors
L.S. Frei, M. Blake

Tectonostratigraphic terranes of the Croissilles Harbour region, South Island, New Zealand Tectonostratigraphic terranes of the Croissilles Harbour region, South Island, New Zealand

The boundary between Hokonui and Te Anau assemblages is flanked by a broad (10–20 km) zone of imbricated slabs of late Paleozoic and Mesozoic lithostratigraphic terranes. Five terranes are mapped, three of predominantly sedimentary character (Dun Mountain‐Maitai, Rai, Pelorus) are separated by two consisting of ophiolitic melange (Patuki, Croisilles). A regional stratigraphy is mapped...
Authors
C. Landis, M. Blake

Correlation of early Cretaceous blueschists in Washington, Oregon and northern California Correlation of early Cretaceous blueschists in Washington, Oregon and northern California

The protolith and metamorphic histories of Early Cretaceous blueschists that occur in Washington, Oregon, and California are remarkably similar. These blueschists are the Shuksan metamorphic suite of northwestern Washington, the Condrey Mountain schist of northern California and southern Oregon, and the Pickett Peak terrane of northern California and southwestern Oregon. We suggest that...
Authors
E. Brown, M.C. Blake

Unconformity between Coast Range ophiolite and part of the lower Great Valley sequence, South Fork of Elder Creek, Tehama County, California Unconformity between Coast Range ophiolite and part of the lower Great Valley sequence, South Fork of Elder Creek, Tehama County, California

The South Fork of Elder Creek is located on private property about 6 mi (10 km) northwest of Paskenta, Calif. (Fig. 1). To visit this locality it is necessary to call Mr. Les Sutfin (916-824-4628) and arrange to pick up the key to the gate at his home in Corning. From the Paskenta Store, drive 3.3 mi (5.3 km) north on the Toomes Camp road to the locked gate on the north side of the road...
Authors
Blake, A. Jayko, D. Jones, B. Rogers

In search of the Abrams post office, Trinity County In search of the Abrams post office, Trinity County

An understanding of earth history depends in part on stratigraphy, a division of geology in which the distinctive features of natural units or formations of layered rocks are studied and described and names are assigned to them. The procedures for describing and naming rock units in a uniform way are incorporated in documents known as stratigraphic codes. The North American Stratigraphic...
Authors
Marvin Lanphere, William P. Irwin
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