The petrogenesis and trace-element geochemistry of intermediate lavas from Humphreys Peak, San Francisco volcanic field, Arizona
K.J. Wenrich-Verbeek
1979, Tectonophysics (61) 103-129
The San Francisco Mountain lavas exposed in the upper portion of the southeast slope of Humphreys Peak are composed of three petrographically distinct types: (1) a lower series of hornblende pyroxene andesites; (2) a group of hypersthene dacites; and (3) an upper series of olivine andesites. These rocks have been...
Deep structure under Yellowstone National Park U.S.A.: A continental "hot spot"
H. M. Iyer
1979, Tectonophysics (56) 165-197
In order to understand the origin of long-lived loci of volcanism (sometimes called “hot spots”) and their possible role in global tectonic processes, it is essential to know their deep structure. Even though some work has been done on the crustal, upper-mantle, and deep-mantle structure under some of these “hot...
Marine terrace deformation, San Diego County, California
P.A. McCrory, K. R. Lajoie
1979, Tectonophysics (52) 407-408
The NW—SE trending southern California coastline between the Palos Verdes Peninsula and San Diego roughly parallels the southern part and off-shore extension of the dominantly right-lateral, strike-slip, Newport—Inglewood fault zone. Emergent marine terraces between Newport Bay and San Diego record general uplift and gentle warping on the northeast side of...
Quaternary crustal deformation along a major branch of the San Andreas fault in central California
G. E. Weber, K. R. Lajoie, J.F. Wehmiller
1979, Tectonophysics (52) 378-379
Deformed marine terraces and alluvial deposits record Quaternary crustal deformation along segments of a major, seismically active branch of the San Andreas fault which extends 190 km SSE roughly parallel to the California coastline from Bolinas Lagoon to the Point Sur area. Most of this complex fault zone lies offshore...
Anomalously high uplift rates along the Ventura-Santa Barbara coast, California-tectonic implications
J.F. Wehmiller, A. Sarna-Wojcicki, R. F. Yerkes, K. R. Lajoie
1979, Tectonophysics (52) 380-380
The NW—SE trending segments of the California coastline from Point Arena to Point Conception (500 km) and from Los Angeles to San Diego (200 km) generally parallel major right-lateral strike-slip fault systems. Minor vertical crustal movements associated with the dominant horizontal displacements along these fault systems are recorded in local...
Dislocation modeling of creep-related tilt changes
S. McHugh, M.J.S. Johnston
1979, Tectonophysics (52) 520-520
Tilt changes associated with 1–5 mm of fault creep have been detected at several different locations on the San Andreas fault on tiltmeters within 500 m of the creep observation point. The creep-related tilts have amplitudes of ≤ 0̌.5 μrad and durations...
Monitoring massive fracture growth at 2-km depths using surface tiltmeter arrays
M.D. Wood
1979, Tectonophysics (52) 643-643
Tilt due to massive hydraulic fractures induced in sedimentary rocks at depths of up to 2.2 km have been recorded by surface tiltmeters. Injection of fluid volumes up to 4 · 105 liters and masses of propping agent up to 5 · 105 kg is designed to produce fractures approximately 1 km...
Late Cenozoic uplift of the southwestern Colorado Plateau and adjacent lower Colorado River region
Ivo Lucchitta
1979, Tectonophysics (61) 63-95
Rocks deposited near sea level under marine, estuarine, and lacustrine conditions, and located along the course of the lower Colorado River from the mouth of the Grand Canyon as far as the Mexican border, have been displaced to present positions as high as 880 m a.s.l. and as low as...
A change in fault-plane orientation between foreshocks and aftershocks of the Galway Lake earthquake, ML = 5.2, 1975, Mojave Desert, California
G. S. Fuis, A.G. Lindh
1979, Tectonophysics (52) 601-602
A marked change is observed in P/SV amplitude ratios, measured at station TPC, from foreshocks to aftershocks of the Galway Lake earthquake. This change is interpreted to be the result of a change in fault-plane orientation occurring between foreshocks and aftershocks.The Galway Lake earthquake, ML= 5.2, occurred on June 1, 1975. The first-motion...
Early 20th-century uplift of the northern Peninsular Ranges province of southern California
Spencer H. Wood, Michael R. Elliott
1979, Tectonophysics (52) 249-265
Repeated leveling in the northern Peninsular Ranges province identifies an early 20thcentury episode of crustal upwarping in southern California. The episodic vertical movement is broadly bracketed between 1897 and 1934, and the main deformation is bracketed within 1906–1914 and involved regional up-to-the-northeast tilting of the Santa Ana block of as...
Earliest Phanerozoic or latest Proterozoic fossils from the Arabian Shield
P. Cloud, S.M. Awramik, K. Morrison, D.G. Hadley
1979, Precambrian Research (10) 73-93
We report here the first biologically definable fossils from pre-Saq (pre-Middle Cambrian) rocks of the Arabian Shield. They include the distinctive helically coiled tubular filaments of the oscillatorialean blue-green alga Obruchevella parva as well as two size classes of spheroidal unicells of uncertain affinity. Also present is the conical stromatolite Conophyton and unidentified stromatolites....
CDP seismic sections of the western Beaufort continental margin
Stephen Eittreim, Arthur Grantz
1979, Tectonophysics (59) 251-262
The continental rise, slope, and shelf in the Beaufort Sea off northern Alaska were surveyed with 5600 km of common-depth-point (CDP) seismic data by the U.S. Geological Survey in 1977. The lower continental rise consists of a wedge of at least 4.5 km of low-velocity, generally flat-lying, parallel-bedded sediments. Slump-related...
Geology and tectonic development of the continental margin north of Alaska
Arthur Grantz, Stephen Eittreim, David A. Dinter
1979, Tectonophysics (59) 263-291
The continental margin north of Alaska, as interpreted from seismic reflection profiles, is of the Atlantic type and consists of three sectors of contrasting structure and stratigraphy. The Chukchi sector, on the west, is characterized by the deep late Mesozoic and Tertiary North Chukchi basin and the Chukchi Continental Borderland....
The gravity field of the U.S. Atlantic continental margin
John A. Grow, C.O. Bowin, Deborah R. Hutchinson
1979, Tectonophysics (59) 27-52
Approximately 39,000 km of marine gravity data collected during 1975 and 1976 have been integrated with U.S. Navy and other available data over the U.S. Atlantic continental margin between Florida and Maine to obtain a 10 mgal contour free-air gravity anomaly map. A maximum typically ranging from 0 to +70...
Coal depositional models in some Tertiary and Cretaceous coal fields in the U.S. Western Interior
R. M. Flores
1979, Organic Geochemistry (1) 225-235
Detailed stratigraphic and sedimentological studies of the Tertiary Tongue River Member of the Fort Union Formation in the Powder River Basin, Wyoming, and the Cretaceous Blackhawk Formation and Star Point Sandstone in the Wasatch Plateau, Utah, indicate that the depositional environments of coal played a major role in controlling coal...
Seismic refraction study of the continental edge off the eastern United States
R. E. Sheridan, J. A. Grow, John C. Behrendt, K.C. Bayer
1979, Tectonophysics (59) 1-26
Three long, strike-parallel, seismic-refraction profiles were made on the continental shelf edge, slope and upper rise off New Jersey during 1975. The shelf edge line lies along the axis of the East Coast Magnetic Anomaly (ECMA), while the continental rise line lies 80 km seaward of the shelf edge. Below...
Anomalous topography on the continental shelf around Hudson Canyon
H.J. Knebel
1979, Marine Geology (33) 67-75
Recent seismic-reflection data show that the topography on the Continental Shelf around Hudson Canyon is composed of a series of depressions having variable spacings (< 100 m to 2 km), depths (1–10 m), outlines, and bottom configurations that give the sea floor an anomalous “jagged” appearance in profile. The acoustic...
Effects of oil transferred from incubating gulls to their eggs
Kirk A. King, C.A. LeFever
1979, Marine Pollution Bulletin (10) 319-321
No. 2 fuel oil, or water, was applied to the breast feathers of incubating laughing gulls trapped at their nest site on an island colony in Texas. Gulls were released after treatment and allowed to incubate their eggs for 5 days. Oil was transferred from the feathers of incubating adults...
Clay mineralogy, fine-grained sediment dispersal, and inferred current patterns, lower Cook Inlet and Kodiak shelf, Alaska
James R. Hein, Arnold H. Bouma, Monty A. Hampton, Ross C. Robin
1979, Sedimentary Geology (24) 291-306
Because lower Cook Inlet and Kodiak shelf are being explored and developed for their petroleum resources, it is essential for environmental reasons to understand the sediment dispersal routes and current patterns. The Susitna River flows into upper Cook Inlet and is the source of clay minerals in Holocene deposits found...
Relationship between physical condition of the carbonate fraction and sediment environments: Northern Puerto Rico shelf
O. H. Pilkey, E.I. Fierman, James V. A. Trumbull
1979, Sedimentary Geology (24) 283-290
Each of three sediment types recognizable on the northern Puerto Rico shelf and beaches is characterized by calcareous material in different physical condition. Dark terrigenous sand is accumulating at a relatively rapid rate and has a carbonate fraction containing fresh-appearing angular particles. The pure-carbonate skeletal-sand sediment type has a much...
Research in the United States relative to geochemistry and health
W.L. Petrie, H.L. Cannon
1979, Physics and Chemistry of the Earth (11) 829-847
Increasing concern regarding the effects of the geochemical environment on health in the United States has fostered research studies in a number of universities and government agencies. The necessity to evaluate the effects of natural and man-made elemental excesses in the environment on health requires the establishment of requirements and...
The determination of lead in 13 USGS standard rocks
P. J. Aruscavage, E.Y. Campbell
1979, Talanta (26) 1052-1054
Lead was determined in 13 U.S. Geological Survey standard rocks by graphite furnace atomization and atomic-absorption spectrometry after extraction of lead with diethylammonium diethyldithiocarbamic acid. An analysis of variance of the results obtained from a random sampling of three different bottles of each standard rock showed no heterogeneity among bottles,...
4 NCIC Data Acquisition Guide
Water Resources Division, U.S. Geological Survey
1979, Report
The National Cartographic Information Center (NCIC) is the information branch of the National Mapping Program. NCIC gathers descriptions of cartographic products held by Federal, State and local agencies, and private companies. Computerized information systems are used to edit, store, and distribute these descriptions. The Aerial Photography Summary Record System (APSRS)...
Maps showing late Pleistocene and Holocene evolution of the South Texas continental shelf
Carroll A. Pyle, Henry L. Berryhill Jr., Anita R. Trippet
1979, Miscellaneous Field Studies Map 1134
Interpretation of acoustical profiles has provided insight into the late Quaternary geologic history of the Continental Shelf off South Texas. (See the geographic index map on sheet 1 for location of the area studied.) The profiles reveal the interplay of tectonism, sedimentation, and cyclic fluctuations of sea level in the...
Results of Laboratory Tests on Surficial Sediments from the Upper Continental Slope Northern Gulf of Mexico
James S. Booth
1979, Open-File Report 79-579
The purpose of this report is to present the results of geotechnical, textural, and chemical tests performed on samples from the upper Continental Slope, northern Gulf of Mexico.The samples were collected by a piston corer up to 12 m (40 ft.} in length with a head weight of 908 kg...
