Publications
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Natural remanent magnetization, mag¬netic properties, and oxidation of titanomagnetite in basaltic rocks from DSDP Leg 34
We have made paleomagnetic measurements and investigated the magnetic mineralogy of 24 samples of basalt and diabase from Sites 319, 320, and 321 on the Nazca plate. Sample distributions, locations, and ages of overlying sediments are as follows: Site 319, Hole 319, lat 13°01.04'S, long 101°31.46'W, 2 samples, early Miocene (N8); Site 319, Hole 319A, (same coordinates and age), 12 samples. Site 32
Authors
C. Sherman Grommé, Edward A. Mankinen
Effect of geologic structure and metamorphic fluids on seismic behavior of the San Andreas fault system in central and northern California
No abstract available.
Authors
William P. Irwin, Ivan Barnes
The Oligocene volcanic center at Eureka, Nevada
A volcanic center covering an area of about 80 km2 near Eureka, Nev., and active in the early Oligocene, is characterized by rhyolitic, rhyodacitic. and andesitic pyroclastic rocks, lava flows, and shallow intrusive bodies. These rocks were emplaced as intertonguing and interpenetrative units during a 5-m.y. interval; most of the volcanism was in the last 3 million years of this period (36 to 33 m
Authors
M. C. Blake, E.H. McKee, Richard F. Marvin, Miles L. Silberman, Thomas B. Nolan
Finding activity faults in the San Francisco Bay region
No abstract available.
Authors
Earl E. Brabb
Reconnaissance landslide map of parts of Marin and Sonoma counties, California
No abstract available.
Authors
Carl M. Wentworth, Virgil A. Frizzell
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, many minera
Authors
Donald A. Singer
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
Paleotectonic investigations of the Pennsylvanian System in the United States, Part I: Introduction and regional analyses of the Pennsylvanian System
The Pennsylvanian is the fourth geologic system to be analyzed and synthesized by geologists of the U.S. Geological Survey in the form of a paleotectonic study covering the conterminous United States. Earlier investigations were of the Jurassic, Triassic, and Permian Systems. Results were published as Miscellaneous Geologic Investigation Maps I-175, I-300, and I-450 and in Professional Paper 515.
Authors
Edwin D. McKee, Eleanor J. Crosby, George O. Bachman, Kenneth G. Bell, George H. Dixon, Sherwood E. Frezon, Ernest E. Glick, William P. Irwin, William W. Mallory, William J. Mapel, Edwin K. Maughan, George E. Prichard, Gerald L. Shideler, Gary F. Stewart, Harold R. Wanless, Richard F. Wilson
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 the logical
Authors
Roger D. Borcherdt
A review of recently active faults in Taiwan
Six faults associated with five large earthquakes produced surface displacements ranging from 1 to 3 m in the period 1906 through 1951. Four of the ruptures occurred in the western coastal plain and foothills, and two occurred in the Longitudinal Valley of eastern Taiwan. Maps are included showing the locations and dimensions of the displacements. The published geological literature probably would
Authors
Manuel G. Bonilla
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 metamorphi
Authors
M.C. Blake, Benjamin A. Morgan
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 nonoverlapping fi
Authors
E. H. Bailey, M. C. Blake, Jr.