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...
On radon emanation as a possible indicator of crustal deformation
Chi-Yu King
1979, Tectonophysics (52) 120-120
Radon emanation has been monitored in shallow capped holes by a Tracketch method along several active faults and in the vicinity of some volcanoes and underground nuclear explosions. The measured emanation shows large temporal variations that appear to be partly related to crustal strain changes. This paper proposes a model...
Vertical crustal movements in the Charleston, South Carolina-Savannah, Georgia area
Peter T. Lyttle, Gregory S. Gohn, Brenda Higgins, D.S. Wright
1979, Tectonophysics (52) 183-189
First-order vertical level surveys (National Geodetic Survey) repeated between 1955 and 1975 suggest that modern vertical crustal movements have taken place in the Atlantic Coastal Plain between Charleston, South Carolina and Savannah, Georgia. The relative sense of these movements correlates with the sense of displacement of Tertiary strata on known...
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...
Strain pattern represented by scarps formed during the earthquakes of October 2, 1915, Pleasant Valley, Nevada
R. E. Wallace
1979, Tectonophysics (52) 599-599
The pattern of scarps developed during the earthquakes of October 2, 1915, in Pleasant Valley, Nevada, may have formed as a result of a modern stress system acting on a set of fractures produced by an earlier stress system which was oriented differently. Four major scarps developed in a right-stepping,...
A comparison of long-baseline strain data and fault creep records obtained near Hollister, California
L.E. Slater, Robert O. Burford
1979, Tectonophysics (52) 481-496
A comparison of creepmeter records from nine sites along a 12-km segment of the Calaveras fault near Hollister, California and long-baseline strain changes for nine lines in the Hollister multiwavelength distance-measuring (MWDM) array has established that episodes of large-scale deformation both preceded and accompanied periods of creep activity monitored along...
Changes in rate of fault creep
P. Harsh
1979, Tectonophysics (52) 519-519
Aseismic slip or fault creep is occurring on many faults in California. Although the creep rates are generally less than 10 mm/yr in most regions, the maximum observed rate along the San Andreas fault between San Juan Bautista and Gold Hill in central California exceeds 30 mm/yr. Changes in slip...
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...
Two areas of probable holocene deformation in southwestern Utah
R.E. Anderson, R.C. Bucknam
1979, Tectonophysics (52) 417-430
Recent geologic studies in southwestern Utah indicate two areas of probable Holocene ground deformation. 1. (1) A narrow arm of Lake Bonneville is known to have extended southward into Escalante Valley as far as Lund, Utah. Remnants of weakly developed shoreline features, which we have recently found, suggest that Lake...
Elastic expansion of the lithosphere caused by groundwater withdrawal in south-central Arizona
T.L. Holzer
1979, Tectonophysics (52) 304-304
Relative crustal uplift observed from 1948–1949 to 1967 in the Lower Santa Cruz River Basin in south-central Arizona is attributed at least in part to elastic expansion of the lithosphere induced by the removal, and subsequent loss by evapo transpiration, of 4.35 × 1013 kg of groundwater from alluvium. The area...
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...
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....
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...
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....
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...
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...
Seismicity map of the State of Georgia
C. W. Stover, B.G. Reagor, S. T. Algermissen, L.T. Long
1979, Miscellaneous Field Studies Map 1060
The earthquake data shown on this map and listed in table 1 are a list of earthquakes that were originally used in preparing the Seismic Risk Studies in the United States (Algermissen, 1969) which have been recompiled and updated through 1977. The data have been reexamined and intensities assigned where...
Backwater at bridges and densely wooded flood plains, Thompson Creek near Clara, Mississippi
B.E. Colson, C. O. Ming, George J. Arcement
1979, Hydrologic Atlas 597
Floodflow data that will provide a base for evaluating digital models relating to open-channel flow were obtained at 22 sites on streams in Alabama, Louisiana, and Mississippi. Thirty-five floods were measured. Analysis of the data indicated methods currently in use would be inaccurate where densely vegetated flood plains are crossed...
Faults in parts of north-central and western Houston metropolitan area, Texas
Earl R. Verbeek, Karl W. Ratzlaff, Uel S. Clanton
1979, Miscellaneous Field Studies Map 1136
Hundreds of residential, commercial, and industrial structures in the Houston metropolitan area have sustained moderate to severe damage owing to their locations on or near active faults. Paved roads have been offset by faults at hundreds of locations, butted pipelines have been distorted by fault movements, and fault-induced gradient changes...
Seismicity map of the State of Louisiana
C. W. Stover, B.G. Reagor, S. T. Algermissen
1979, Miscellaneous Field Studies Map 1081
This map is one of a series of seismicity maps produced by the U. S. Geological Survey that show earthquake data of individual states or groups of states at the scale of 1:1,000,000. This map shows only those earthquakes with epicenters located within the boundaries of Louisiana, even though earthquakes...
Seismicity map of the State of Alabama
C. W. Stover, B.G. Reagor, S. T. Algermissen
1979, Miscellaneous Field Studies Map 1059
The earthquake data shown on this map and listed in table 1 are a list of earthquakes that were originally used in preparing the Seismic Risk Studies in the United States (Algermissen, 1969) which have been recompiled and updated through 1977. The data have been reexamined and intensities assigned where...
Vegetation map of the southeastern Uinta Basin, Utah and Colorado
John R. Butler, J. Larry England
1979, IMAP 1141
This map has been prepared by the U.S. Geological Survey as part of a hydrologic investigation of the southeastern Uinta Basin in cooperation with the Utah State Engineer and the U.S. Bureau of Land Management. The map defines the extent of dominant types of vegetation within the study area prior...
Geologic map of the Margaritifer Sinus Quadrangle of Mars
R.S. Saunders
1979, IMAP 1144
The Margaritifer Sinus quadrangle lies within a broad north-sloping trough, the Chryse lowlands, between the elevated Tharsis plateau to the west and the cratered upland to the east. The rugged, uniquely martian chaotic terrain is best developed in this quadrangle. Sinuous furrows a few kilometers wide and as...
Geologic map of the Amenthes Quadrangle of Mars
K.H. Hiller
1979, IMAP 1110
The Amenthes quadrangle includes two main physiographic and geologic subdivisions. In the southern part of the quadrangle, densely cratered plateaus rise about 3 km above sparsely to moderately cratered plains. The low plains that form Elysium Planitia also build the eastern flank of the Isidis basin, which mostly lies...
Backwater at bridges and densely wooded flood plains, Yockanookany River near Thomastown, Mississippi
B.E. Colson, C. O. Ming, George J. Arcement
1979, Hydrologic Atlas 599
Floodflow data that will provide a base for evaluating digital models relating to open-channel flow were obtained at 22 sites on streams in Alabama, Louisiana, and Mississippi. Thirty-five floods were measured. Analysis of the data indicated methods currently in use would be inaccurate where densely vegetated flood plains are crossed...
