Publications
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Archean and Proterozoic crustal evolution: Evidence from crustal seismology Archean and Proterozoic crustal evolution: Evidence from crustal seismology
Seismic-velocity models for Archean and Proterozoic provinces throughout the world are analyzed. The thickness of the crust in Archean provinces is generally found to be about 35 km (except at collisional boundaries), whereas Proterozoic crust has a significantly greater thickness of about 45 km and has a substantially thicker high-velocity (>7.0 km/s) layer at the base. We consider two...
Authors
R. Durrheim, Walter D. Mooney
Basin and range crustal and upper mantle structure, northwest to central Nevada Basin and range crustal and upper mantle structure, northwest to central Nevada
We present an interpretation of the crustal and uppermost mantle structure of the Basin and Range of northwestern Nevada based on seismic refraction/wide‐angle reflection, near‐vertical reflection, and gravity data. In comparison to most previous estimates, we find that the crust is somewhat thicker (32–36 km versus 22–30 km), and the uppermost mantle velocity is somewhat higher (8.0 km...
Authors
Rufus D. Catchings, Walter D. Mooney
Probing the Earth's strength: Can we measure small stress at high pressure? Probing the Earth's strength: Can we measure small stress at high pressure?
Simulating the conditions and processes that occur in the Earth's deep interior has been a major goal of experimental geophysics since the 1920s. In particular, pioneers such as P. W. Bridgman, David Griggs, Hugh Heard, Mervyn Paterson, William Brace, and their colleagues sought to establish the basic relations between differential stresses and rock and mineral deformation under pressure
Authors
A. Kronenberg, Stephen H. Kirby
Crustal structure of accreted terranes in southern Alaska, Chugach Mountains and Copper River Basin, from seismic refraction results Crustal structure of accreted terranes in southern Alaska, Chugach Mountains and Copper River Basin, from seismic refraction results
Seismic refraction data were collected along a 320-km-long "transect' line in southern Alaska, crossing the Prince William, Chugach, Peninsular, and Wrangellia terranes, and along several shorter lines within individual terranes. Velocity structure in the upper crust (less than 9-km depth) differs among the four terranes. In contrast, layers in the middle crust (9- to 25-km depth) in...
Authors
G. S. Fuis, E. L. Ambos, Walter D. Mooney, N.I. Christensen, E. Geist
A C language implementation of the SRO (Murdock) detector/analyzer A C language implementation of the SRO (Murdock) detector/analyzer
A signal detector and analyzer algorithm was described by Murdock and Hutt in 1983. The algorithm emulates the performance of a human interpreter of seismograms. It estimates the signal onset, the direction of onset (positive or negative), the quality of these determinations, the period and amplitude of the signal, and the background noise at the time of the signal. The algorithm has...
Authors
James N. Murdock, Scott E. Halbert
Large-scale variation in lithospheric structure along and across the Kenya rift Large-scale variation in lithospheric structure along and across the Kenya rift
The Kenya rift is one of the classic examples of a continental rift zone: models for its evolution range from extension of the lithosphere by pure shear1, through extension by simple shear2, to diapiric upwelling of an asthenolith3. Following a pilot study in 19854, the present work involved the shooting of three seismic refraction and wide-angle reflection profiles along the axis...
Authors
C. Prodehl, J. Mechie, W. Kaminski, K. Fuchs, C. Grosse, H. Hoffmann, R. Stangl, R. Stellrecht, M.A. Khan, Peter K.H. Maguire, W. Kirk, Gordon R. Keller, A. Githui, M. Baker, Walter D. Mooney, E. Criley, J. Luetgert, B. Jacob, H. Thybo, M. Demartin, S. Scarascia, A. Hirn, J. R. Bowman, I. Nyambok, S. Gaciri, J. Patel, E. Dindi, D.H. Griffiths, R.F. King, A. E. Mussett, L.W. Braile, G. Thompson, K. Olsen, S. Harder, R. Vees, D. Gajewski, A. Schulte, J. Obel, F. Mwango, J. Mukinya, D. Riaroh
Geodetic estimate of coseismic slip during the 1989 Loma Prieta, California, Earthquake Geodetic estimate of coseismic slip during the 1989 Loma Prieta, California, Earthquake
Offsets in the relative positions of geodetic stations resulting from the Loma Prieta earthquake can be explained with a dislocation model that includes buried oblique slip on a rupture surface extending 37 km along the strike of the San Andreas fault, dipping 70° to the SW, and extending from a depth of about 5 to 17.5 km. Assuming uniform slip on a rectangular surface, the mean values...
Authors
Michael Lisowski, W.H. Prescott, James C. Savage, M. J. Johnson
A possible geodetic anomaly observed prior to the Loma Prieta, California, Earthquake A possible geodetic anomaly observed prior to the Loma Prieta, California, Earthquake
Monthly measurements since mid‐1981 of distance from a geodetic station located 11 km from the epicenter of the Loma Prieta earthquake (Ms = 7.1; October 17, 1989) to three stations 30 to 40 km distant provides an unusually complete record of deformation in the epicentral region in the years prior to an earthquake. Roughly 1.3 years before the earthquake, at about the time of the first...
Authors
Michael Lisowski, W.H. Prescott, James C. Savage, Jerry L. Svarc
An apparent shear zone trending north‐northwest across the Mojave Desert into Owens Valley, eastern California An apparent shear zone trending north‐northwest across the Mojave Desert into Owens Valley, eastern California
Strain rates measured at four geodetic networks in eastern California situated between northern Owens Valley and the Transverse Ranges along a small circle drawn about the Pacific‐North America pole of rotation are remarkably consistent. Each exhibits 0.14 μrad/yr simple right‐lateral engineering‐shear‐strain accumulation across the local vertical plane tangent to the small circle. Local...
Authors
James C. Savage, Michael Lisowski, W.H. Prescott
Liquefaction and foundation failure of Chevron oil and gasoline tanks at Moss Landing, California Liquefaction and foundation failure of Chevron oil and gasoline tanks at Moss Landing, California
Liquefaction of gray, coarse‐ to medium‐grained, esturine sand during the October 17, 1989 Loma Prieta (Ms=7.1) earthquake led to foundation failures of oil and tanks at the Chevron Marine Station at Moss Landing located about 25 km south‐southeast of the epicenter. Differential settlement of the foundations resulted in 1° to 6° of the tanks towards one another and an associated 2° to 7°
Authors
Martitia Tuttle, Patience Cowie, John Tinsley, Michael Benett, John Berrill
Preliminary velocity and resistivity models of the Loma Prieta Earthquake region Preliminary velocity and resistivity models of the Loma Prieta Earthquake region
A preliminary three-dimensional velocity model of the Loma Prieta epicentral region in the Santa Cruz Mountains of California has been derived using raypaths from aftershocks recorded by the U.S.G.S. seismic network. In addition, a magnetotelluric sounding profile was completed prior to the earthquake and a two-dimensional resistivity model computed. The velocity and resistivity models...
Authors
Donna Eberhart-Phillips, Victor F. Labson, William D. Stanley, Andrew J. Michael, Brian D. Rodriguez
On the rupture zone and effects of local geologic conditions on damages and ground motions for the Armenian earthquakes of December 7, 1988 On the rupture zone and effects of local geologic conditions on damages and ground motions for the Armenian earthquakes of December 7, 1988
No abstract available.
Authors
Roger D. Borcherdt, C. Langer, John R. Filson, D.W. Simpson, G. Glassmoyer, M. Andrews, E. Cranswick