Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2350
Mechanisms of Cenozoic tectonic rotation, Pacific Northwest Convergent Margin, U.S.A.
Large clockwise rotations (15–80°) are characteristic of Cenozoic volcanic and sedimentary rocks along the convergent margin of the northwestern United States. Abundant paleomagnetic data from 62–12 m.y. old rocks in forearc, arc, and backarc regions show that rotation increases with age and with proximity to the coast. Paleomagnetic and structural studies both support dextral shear as a significa
Authors
Ray E. Wells
Paleomagnetism and tectonic rotation of the lower Miocene Peach Springs Tuff: Colorado Plateau, Arizona, to Barstow, California
We have determined remanent magnetization directions of the lower Miocene Peach Springs Tuff at 41 localities in western Arizona and southeastern California. An unusual northeast and shallow magnetization direction confirms the proposed geologic correlation of isolated outcrops of the tuff from the Colorado Plateau to Barstow, California, a distance of 350 km. The Peach Springs Tuff was apparently
Authors
Ray E. Wells, John W. Hillhouse
Correlation of Miocene flows of the Columbia River Basalt Group from the central Columbia River Plateau to the coast of Oregon and Washington
Nearly twenty flows of the Columbia River Basalt Group (CRBG) can be paleomagnetically and chemically correlated westward as far as 500 km from the Columbia Plateau in Washington, through the Columbia Gorge, to the Coast Range of Oregon and Washington. In the Coast Range near Cathlamet, Washington, the CRBG flow stratigraphy includes 10 flows of Grande Ronde Basalt (1 low-MgO R2 flow, 6 low-MgO N2
Authors
Ray E. Wells, R. W. Simpson, R. D. Bentley, Melvin H. Beeson, Margaret T. Mangan, Thomas L. Wright
Paleomagnetic study of the Eastern Klamath terrane, California, and implications for the tectonic history of the Klamath Mountains Province
Paleomagnetic study of Permian through Jurassic volcanic and sedimentary strata of the Eastern Klamath terrane has shown the remanent magnetization of many of these rocks to be prefolding and most likely primary. Similarities in magnetic declinations recorded by coeval strata over a broad area are consistent with the hypothesis that the terrane, in general, has behaved as a single rigid block. Pal
Authors
Edward A. Mankinen, William P. Irwin, C. Sherman Grommé
Minimum earthquake magnitude associated with coseismic surface faulting
No abstract available.
Authors
Manuel G. Bonilla
Pb isotopic evidence for the formation of Proterozoic crust in the southwestern United States
No abstract available.
Authors
J. L. Wooden, J. S. Stacey, Keith A. Howard, B. R. Doe, D. M. Miller
New and revised lithostratigraphic units from the southwestern New England Fold Belt
New and revised lithostratigraphic units are recognized in northern New South Wales. New lithostatigraphic units are: Cara Formation, Whitlow Formation, Bobs Creek Formation, Nangahrah Formation, and Dinoga Formation. Revision of the Woolomin beds to Woolomin Group and Woodsreef Melange is proposed.
Authors
M. Clark Blake, B. Murchey
Metamorphic and tectonic evolution of the Franciscan Complex, northern California: Chapter 38
No abstract available.
Authors
M. Clark Blake, A. S. Jayko, R. J. McLaughlin, M. B. Underwood
Comment and reply on "Sediment-yield history of a small basin in southern Utah, 1937-1976: Implications for land management and geomorphology"
No abstract available.
Authors
E.B. Nuhfer, Richard Hereford
Comment and reply on "Bacterially mediated diagenetic origin for chert-hosted manganese deposits in the Franciscan Complex, California Coast Ranges"
No abstract available.
Authors
Loren A. Raymond, James R. Hein, Randolph A. Koski
A guide to commonly used map projections prepared for use in HyperCard, 1988
This guide briefly describes and illustrates the characteristics of 17 map projections commonly used to present thematic data. By means of simple sketches of the basic grid system of longitude and latitude known as the Earth's graticule, the guide shows examples of the following categories of map projections: planes (azimuthal), cones, cylinders, and miscellaneous. The text gives examples of thema
Authors
Tau Rho Alpha, Joe F. Vigil, Lauren Buchholz
Mineral resource assessment of the Wiseman 1° by 3° quadrangle, Alaska
No abstract available.
Authors
James D. Bliss, W. P. Brosge, J. T. Dillon, J.T. Dutro, J.B. Cathrall, J. W. Cady