Publications
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The crustal structure of the axis of the Great Valley, California, from seismic refraction measurements
In 1982 the U.S. Geological Survey collected six seismic refraction profiles in the Great Valley of California: three axial profiles with a maximum shot-to-receiver offset of 160 km, and three shorter profiles perpendicular to the valley axis. This paper presents the results of two-dimensional raytracing and synthetic seismogram modeling of the central axial profile. The crust of the central Great
Authors
W.S. Holbrook, Walter D. Mooney
Crustal structure of Yunnan Province, People's Republic of China, from seismic refraction profiles
Seismic refraction, profiles in Yunnan Province, southwestern China, define the crustal structure in an area of active tectonics on the southern end of the Himalaya-Burma arc. The crustal thickness ranges from 38 to 46 kilometers, and the relatively low mean crustal velocity indicates a crustal composition compatible with normal continental crust and consisting mainly of meta-sedimentary and silic
Authors
Rong-Ju Kan, Hong-Xiang Hu, Rong-Sheng Zeng, Walter D. Mooney, T. McEvilly
Influence of welded boundaries in anelastic media on energy flow, and characteristics of P, S-I, and S-II waves: Observational evidence for inhomogeneous body waves in low-loss solids
A general computer code, developed to calculate anelastic reflection-refraction coefficients, energy flow, and the physical characteristics for general P, S-I, and S-II waves, quantitatively describes physical characteristics for wave fields in anelastic media that do not exist in elastic media. Consideration of wave fields incident on boundaries between anelastic media shows that scattered wave f
Authors
Roger D. Borcherdt, Gary Glassmoyer, Leif Wennerberg
Short-period strain (0.1–105 s): Near-source strain field for an earthquake (ML 3.2) near San Juan Bautista, California
Measurements of dilational earth strain in the frequency band 25–10−5 Hz have been made on a deep borehole strainmeter installed near the San Andreas fault. These data are used to determine seismic radiation fields during nuclear explosions, teleseisms, local earthquakes, and ground noise during seismically quiet times. Strains of less than 10−10 on these instruments can be clearly resolved at sho
Authors
M.J.S. Johnston, Roger D. Borcherdt, A. T. Linde
Implications of recent advances in instrumentation for strong-motion studies
No abstract available.
Authors
Roger D. Borcherdt
Crustal structure of Oaxaca, Mexico, from seismic refraction measurements
Seismic refraction and gravity data have been analyzed to obtain a model of the compressional-wave velocity structure of the ocean-to-continent transition in the State of Oaxaca in southwestern Mexico. Crustal thickness on the continent at the latitude 18°N is 45 ± 4 km, based on reflected phases from the Moho discontinuity. The crust has been modeled with three layers, with velocities of 4.3 to 4
Authors
C.M. Valdes, Walter D. Mooney, S.K. Singh, C. Lomnitz, James H. Luetgert, C.E. Helsley, B.T.R. Lewis, M. Mena
Report on recommended list of structures for seismic instrumentation in southeastern United States
No abstract available.
Authors
Joyce B. Bagwell, Mehmet Çelebi, R. Elling, Charles Lindbergh, R.P. Maley, R. Pool, J. Radziminski, C. Simmons, D. Smits, P. Sparks, Pradeep Talwani
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