Publications
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The velocity field along the San Andreas Fault in central and southern California
The velocity field within a 100‐km‐broad zone centered on the San Andreas fault between the Mexican border and San Francisco Bay has been inferred from repeated surveys of trilateration networks in the 1973–1989 interval. The velocity field has the appearance of a shear flow that remains parallel to the local strike of the fault even through such major deflections as the big bend of the San Andrea
Authors
Michael Lisowski, James C. Savage, W. H. Prescott
Strain accumulation in western Washington
The Juan de Fuca plate is subducted beneath the North American plate off the coast of Washington at a rate of about 40 mm/yr N68°E. The average principal strain rates (extension reckoned positive) measured in northwestern Washington are as follows: Olympic peninsula 25 km south of Port Angeles from 1982 through 1990, and and near Seattle from 1972 through 1985, and . Both strain measurements ar
Authors
James C. Savage, Michael Lisowski, W. H. Prescott
Tide gage measurements of uplift along the south coast of Alaska
Annual mean sea levels along the south coast of Alaska are used to measure uplift along the Alaska‐Aleutian subduction zone. Oceanographic effects are removed from the observed annual mean sea levels by subtracting a correction that is proportional to the sea level fluctuations observed in southeast Alaska. That correction is effective in reducing fluctuations in the observed, annual mean sea leve
Authors
James C. Savage, George Plafker
Criticism of some forecasts of the National Earthquake Prediction Evaluation Council
The Working Group on California Earthquake Probabilities has assigned probabilities for rupture in the interval from 1988 to 2018 to various segments of the San Andreas fault on the basis of the lognormal distribution of recurrence times of characteristic earthquakes postulated by Nishenko and Buland (1987). I question the validity of those probabilities on the basis of three separate arguments: (
Authors
James C. Savage
Continental crustal evolution observations
How has the continental crust evolved? What are the primary processes responsible for its composition, structure, and mode of deformation? What role do fluids play in deep crustal processes? In the last dozen years, geophysicists have obtained images of the deep continental crust that can be used to examine these questions and refine geologic models of crustal evolution. In this report we summariz
Authors
Walter D. Mooney, R. Meissner
Strain accumulation along the Denali Fault at the Nenana River and Delta River Crossings, Alaska
Surveys of trilateration networks across the Denali fault at the Nenana River in 1982, 1984, and 1988 and at the Delta River in 1975, 1979, 1982, and 1984 indicate a minor (0.10±0.04 μstrain/yr) northeastward uniaxial extension. The component of right‐lateral shear‐strain accumulation across the fault is not significant at the two‐standard‐deviation level. At the Delta River network the strain acc
Authors
James C. Savage, Michael Lisowski
The Loma Prieta earthquake, ground motion, and damage in Oakland, Treasure Island, and San Francisco
The basis of this study is the acceleration, velocity, and displacement wave-forms of the Loma Prieta earthquake (18 October 1989; M = 7.0) at two rock sites in San Francisco, a rock site on Yerba Buena Island, an artificial-fill site on Treasure Island, and three sites in Oakland underlain by thick sections of poorly consolidated Pleistocene sediments. The waveforms at the three rock sites displa
Authors
Thomas C. Hanks, A. Gerald Brady
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 models tha
Authors
R. Durrheim, Walter D. Mooney
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/s versus 7
Authors
Rufus D. Catchings, Walter D. Mooney
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-temperatu
Authors
A. Kronenberg, Stephen H. Kirby
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 some case ext
Authors
G. S. Fuis, E. L. Ambos, Walter D. Mooney, N.I. Christensen, E. Geist
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, across the marg
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