Publications
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Lamoille Canyon nappe in the Ruby Mountains metamorphic core complex, Nevada
No abstract available.
Authors
Keith A. Howard
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 Code (198
Authors
Marvin A. Lanphere, William P. Irwin
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, but, by d
Authors
M. B. Underwood, M. Clark Blake, D. G. Howell
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 within the L
Authors
C. A. Landis, M. Clark Blake
Attenuation of the Coast Range ophiolite by extensional faulting and nature of the Coast Range "thrust," California
The late Mesozoic Coast Range ophiolite and Great Valley sequence in California were juxtaposed against the Franciscan Complex during a long tectonic history that included imbricate thrust faulting, low‐angle detachment, and high‐angle reverse faulting. Many low‐angle faults previously mapped as thrusts invariably juxtapose younger over older rocks, suggesting a normal sense of offset. We infer th
Authors
A. S. Jayko, M. Clark Blake, Tekla Harms
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 the upper
Authors
L.S. Frei, M. Clark Blake
Geologic terranes of coastal northern California and southern Oregon
No abstract available.
Authors
A. S. Jayko, M. Clark Blake
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 these bodi
Authors
E. H. Brown, M. C. Blake
Geochemistry and tectonic setting of some volcanic rocks of the Franklinian assemblage, central and eastern Brooks Range
No abstract available.
Authors
Thomas E. Moore
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. From here
Authors
M. C. Blake, Jr., A. S. Jayko, D. L. Jones, B. W. Rogers
Petrology and K-Ar ages of the Misheguk igneous sequence, an allochthonous mafic and ultramafic complex, and its metamorphic aureole, western Brooks Range, Alaska
No abstract available.
Authors
J.M. Boak, D. L. Turner, D.J. Henry, Thomas E. Moore, W. K. Wallace
Dinosaurs, pollen and spores, and the age of the Ojo Alamo Sandstone, San Juan Basin, New Mexico
The Ojo Alamo Sandstone of the San Juan Basin of New Mexico is composed of interbedded conglomeratic sandstone, sandstone, siltstone, and mudstone. Conglomerates are found in the western part of the basin; siliceous pebbles diminish in size both southward and eastward across the basin, becoming rare to nonexistent in the eastern part. There is great variation in the internal stratigraphy of the Oj
Authors
James E. Fassett, S. G. Lucas, F.M. O'Neill