Publications
Filter Total Items: 1151
Studies for seismic zonation of the San Francisco Bay region Studies for seismic zonation of the San Francisco Bay region
The analyses presented in the preceding six papers show that the geologic setting of the San Francisco Bay region has a dominant influence on potential earthquake hazards. The strong correlation between geologic conditions and the amount of earthquake damage in 1906 emphasizes the importance of this influence and demonstrates the need for seismic zonation. Seismic zonation can provide...
Authors
Roger D. Borcherdt
Reconnaissance landslide map of parts of Marin and Sonoma counties, California Reconnaissance landslide map of parts of Marin and Sonoma counties, California
No abstract available.
Authors
Carl M. Wentworth, Virgil A. Frizzell
By
Geology, Energy, and Minerals Mission Area, Natural Hazards Mission Area, Energy Resources Program, Landslide Hazards Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geologic Hazards Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Mineral resource models and the Alaskan Mineral Resource Assessment Program Mineral resource models and the Alaskan Mineral Resource Assessment Program
The least exacting demand that can be made of any model is that it serves as a device whereby we can predict actual physical happenings. Another demand which could be made is that the physical happenings predicted be in some way relevant to man, either by allowing him to anticipate future uncontrollable events or by demonstrating the possible consequences of various decisions. To date...
Authors
Donald A. Singer
Finding activity faults in the San Francisco Bay region Finding activity faults in the San Francisco Bay region
No abstract available.
Authors
Earl E. Brabb
Southern Patagonia—Glacial events between 4 m.y. and 1 m.y. ago Southern Patagonia—Glacial events between 4 m.y. and 1 m.y. ago
No abstract available.
Authors
John H. Mercer, Robert J. Fleck, Edward A. Mankinen, Walter Sander
Rutile and sphene in blueschist and related high-pressure facies rocks Rutile and sphene in blueschist and related high-pressure facies rocks
Sphene and rutile are characteristic accessory minerals of blueschist facies metamorphic rocks. However, only sphene is present in the lowerr grade blueschist assemblages. In many areas of the world these blueschists pass into, or are in fault contact with, higher grade glaucophane schists, rutile-bearing amphibolites, and eclogites. The origin of the rutile may be related to a prograde
Authors
M.C. Blake, Benjamin A. Morgan
Major chemical characteristics of Mesozoic Coast Range ophiolite in California Major chemical characteristics of Mesozoic Coast Range ophiolite in California
Sixty-four major element analyses of rocks representative of the Coast Range ophiolite in California were compared with analyses of other onland ophiolite sequences and those of rocks from oceanic ridges. The rocks can be classed in five groups harzburgite-dunite, clinopyroxenite-wehrlite, gabbro, basalt-spilite, and keratophyre-quartz keratophyre which on various diagrams occupy...
Authors
E. H. Bailey, Blake
Fresh lunar impact craters: Review of variations in size Fresh lunar impact craters: Review of variations in size
Thirty-three morphologic characteristics are reviewed for fresh lunar impact craters wide than1 km. Bar graphs express the way each characteristic varies with crater size. The features are grouped as crater structure, ejecta, and downhill flow features. Major structural transition occur at diameters of about 15 and 200 km. Details of the ejecta blanket, which include several kinds of...
Authors
Keith A. Howard
Lunar basin formation and highland stratigraphy Lunar basin formation and highland stratigraphy
Multiring impact basins, formed after solidification of the lunar crust, account for most or all premare regional deposits and structures expressed in the lunar landscape and for major topographic and gravity variations. A fresh basin has two or more concentric mountain rings, a lineated ejecta blanket, and secondary impact craters. Crackled material on the floor may be impact melt. The...
Authors
Keith A. Howard, D.E. Wilhelms, D. H. Scott
Origin of Franciscan melanges in Northern California Origin of Franciscan melanges in Northern California
In northern California, chaotic Franciscan melange occurs beneath the overlying ophiolite and Great Valley Sequence. Identical melanges occur to the west, separating well-bedded, coherent Franciscan units that differ markedly in age. Detailed studies in several places indicate that these melanges mark the boundaries of imbricate thrust sheets, and they appear to occur at several discrete
Authors
M. Clark Blake, D. L. Jones
Geologic sketch of the Klamath Mountains and Coast Ranges of northern California and southern Oregon Geologic sketch of the Klamath Mountains and Coast Ranges of northern California and southern Oregon
No abstract available.
Authors
W. P. Irwin, E.W. Wolfe, M.C. Blake, C.G. Cunningham
Gravity anomalies in the Galapagos Islands area Gravity anomalies in the Galapagos Islands area
No abstract available.
Authors
Anthony B. Watts, J. R. Cochran, J. E. Case, S. L. Ryland, Tom Simkin, Keith A. Howard