Publications
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Seismic measurements of the internal properties of fault zones
The internal properties within and adjacent to fault zones are reviewed, principally on the basis of laboratory, borehole, and seismic refraction and reflection data. The deformation of rocks by faulting ranges from intragrain microcracking to severe alteration. Saturated microcracked and mildly fractured rocks do not exhibit a significant reduction in velocity, but, from borehole measurements, de
Authors
Walter D. Mooney, A. Ginzburg
A plate flexure approximation to postseismic and interseismic deformation
The rather large postseismic deformation that is associated with two‐dimensional dip‐slip faulting in the lithosphere is related to the bending of a free plate generated by dip‐slip faulting. In the absence of gravity, asthenosphere relaxation eventually permits the faulted lithosphere to assume the dihedral configuration of a faulted free plate. For thrust faulting, the faulted area is depressed
Authors
James C. Savage, Guohua Gu
Rate and depth of pedogenic-carbonate accumulation in soils: Formation and testing of a compartment model.
The rate and depth of pedogenic carbonate accumulation in soils formed in Quaternary alluvium may be viewed as a theoretical problem that involves the mutual interaction of several independent and dependent soil-forming variables. We propose a model for carbonate accumulation in which the soil column is defined by a vertical sequence of 1-cm2-area compartments, each with a specified texture, bulk
Authors
Leslie D. McFadden, John Tinsley
Inversion of seismic refraction data in planar dipping structure
A new method is presented for the direct inversion of seismic refraction data in dipping planar structure. Three recording geometries, each consisting of two common-shot profiles, are considered: reversed, split, and roll-along profiles. Inversion is achieved via slant stacking the common-shot wavefield to obtain a delay time—slowness (tau—p) wavefield. The tau—p curves from two shotpoints describ
Authors
B. Milkereit, Walter D. Mooney, W. M. Kohler
The relocation of microearthquakes in the northern Mississippi Embayment
Three-component seismograms, recorded by a small array of digital instruments in the northern Mississippi embayment, consistently show a high-amplitude phase on the vertical component that arrives approximately 0.8 s before the shear wave. On the basis of its timing and apparent velocity, this phase is identified as an S-P conversion from the boundary between the unconsolidated Cenozoic sediments
Authors
M.C. Andrews, Walter D. Mooney, R.P. Meyer
Plasticity at crack tips in Gd3Ga5O12 garnet single crystals deformed at temperatures below 950°C
Single crystals of Gd3Ga5O12 have been strained under confining pressure (1 5 GPa) at temperatures below 950°C. No evidence for macroscopic plasticity was found, but transmission electron microscopy revealed dislocation generation at crack tips. Deformation mechanisms are different from those operating in the high-temperature regime: extending stacking faults in {110} planes and the 〈010〉{100} gli
Authors
H. Garem, J. Rabier, Stephen H. Kirby
Report on recommended list of structures for seismic instrumentation in San Bernardino County, California
No abstract available.
Authors
G. Brady, Mehmet Çelebi, C. Rojahn, Wilfred Iwan, G. Hart, G. Pardoen, L. Schoelkopf, R. Haskell, K. Topping, Erdal Safak, R.P. Maley
Crustal refraction profile of the Long Valley caldera, California, from the January 1983 Mammoth Lakes earthquake swarm
Seismic-refraction profiles recorded north of Mammoth Lakes, California, using earthquake sources from the January 1983 swarm complement earlier explosion refraction profiles and provide velocity information from deeper in the crust in the area of the Long Valley caldera. Eight earthquakes from a depth range of 4.9 to 8.0 km confirm the observation of basement rocks with seismic velocities ranging
Authors
James H. Luetgert, Walter D. Mooney
Crustal structure of the southern Calaveras fault zone, central California, from seismic refraction investigations
A magnitude 5.7 earthquake on 6 August 1979, within the Calaveras fault zone, near Coyote Lake of west-central California, motivated a seismic-refraction investigation in this area. A northwest-southeast profile along the fault, as well as two fan profiles across the fault were recorded to examine the velocity structure of this region.The analysis of the data reveals a complicated upper crustal ve
Authors
Peter Blumling, Walter D. Mooney, William H. K. Lee
A seismic-refraction profile across the San Andreas, Sargent, and Calaveras faults, west-central California
In 1981, the United States Geological Survey recorded a seismic-refraction profile across the southern Santa Cruz Mountains in west-central California to examine the shallow velocity structure of this seismogenic region. This 40-km-long profile, which consisted of three shotpoints, extended northeastward from near Watsonville, California, to Coyote Lake, crossing the San Andreas, Sargent, and Cala
Authors
Walter D. Mooney, Robert H. Colburn
In situ stress, natural fracture distribution, and borehole elongation in the Auburn Geothermal Well, Auburn, New York
Hydraulic fracturing stress measurements and a borehole televiewer survey were conducted in a 1.6‐km‐deep well at Auburn, New York. This well, which was drilled at the outer margin of the Appalachian Fold and Thrust Belt in the Appalachian Plateau, penetrates approximately 1540 m of lower Paleozoic sedimentary rocks and terminates 60 m into the Precambrian marble basement. Analysis of the hydrauli
Authors
Stephen H. Hickman, John H. Healy, Mark D. Zoback
High-frequency observations and source parameters of microearthquakes recorded at hard-rock sites
We have estimated the source parameters of 53 microearthquakes recorded in July 1983 which were aftershocks of the Miramichi, New Brunswick, earthquake that occurred on 9 January 1982. These events were recorded by local three-component digital seismographs at 400 sps/component from 2-Hz velocity transducers sited directly on glacially scoured crystalline basement outcrop. Hypocentral distances ar
Authors
Edward Cranswick, Robert Wetmiller, John Boatwright