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Publications

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The geology and distribution of impact craters on Venus: What are they telling us?

Magellan has revealed an ensemble of impact craters on Venus that is unique in many important ways. We have compiled a data base describing the 842 craters on 89% of Venus' surface mapped through orbit 2578. (The craters range in diameter from 1.5 to 280 km.) We have studied the distribution, size‐density, morphology, geology, and associated surface properties of these craters both in the aggregat
Authors
G. G. Schaber, R.G. Strom, H. J. Moore, Laurence A. Soderblom, Randolph L. Kirk, D.J. Chadwick, D.D. Dawson, Lisa R. Gaddis, J. M. Boyce, Joel F. Russell

Kenya Rift International Seismic Project, 1989–1990 experiment

Ever since Gregory's work at the turn of the century, the extensional structures extending through central Kenya have been recognized as the classic example of a continental rift zone. Because of the scale and variety of rift features present, this locality has fascinated geologists and geophysicists since its discovery.
Authors
G. Randy Keller, L.W. Braile, P.M. Davis, R.P. Meyer, Walter D. Mooney

Landslides triggered by Hurricane Hugo in eastern Puerto Rico, September 1989

On the morning of September 18, 1989, a category-four hurricane struck eastern Puerto Rico with a sustained wind speed in excess of 46 m/s. The 24-h rainfall accumulation from the hurricane ranged from 100 to 339 mm. Average rainfall intensities ranging from 34 to 39 mm/h were calculated for 4 and 6 h periods, respectively, at a rain gage equipped with satellite telemetry, and at an observer stati

Authors
Matthew C. Larsen, Angel J. Torres-Sanchez

Deep seismic sounding in northern Eurasia

For nearly 40 years, the former Soviet Union has carried out an extensive program of seismic studies of the Earth's crust and upper mantle, known as “Deep Seismic Sounding” or DSS [Piwinskii, 1979; Zverev and Kosminskaya, 1980; Egorkin and Pavlenkova, 1981; Egorkin and Chernyshov, 1983; Scheimer and Borg, 1985]. Beginning in 1939–1940 with a series of small-scale seismic experiments near Moscow, D
Authors
H. M. Benz, J. D. Unger, W.S. Leith, Walter D. Mooney, L. Solodilov, A.V. Egorkin, V.Z. Ryaboy

Lunar impact basins and crustal heterogeneity: New western limb and far side data from Galileo

Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale
Authors
Michael J.S. Belton, James W. Head, Carle m. Pieters, Ronald Greeley, Alfred S. McEwen, G. Neukum, Kenneth P. Klaasen, C.D. Anger, M. H. Carr, C. R. Chapman, M. E. Davies, F. P. Fanale, P.J. Gierasch, R. Greenberg, A. Ingersoll, Torrence Johnson, B. Paczkowski, C.B. Pilcher, J. Veverka

On the characteristics of local geology and their influence on ground motions generated by the Loma Prieta earthquake in the San Francisco Bay region, California

Strong ground motions recorded at 34 sites in the San Francisco Bay region from the Loma Prieta earthquake show marked variations in characteristics dependent on crustal structure and local geological conditions. Peak horizontal acceleration and velocity inferred for sites underlain by “rock” generally occur on the transverse component of motion. They are consistently greater with lower attenuatio
Authors
Roger D. Borcherdt, Gary Glassmoyer

Thin, low‐velocity crust beneath the southern Yukon‐Tanana Terrane, east central Alaska: Results from Trans‐Alaska crustal transect refraction/wide‐angle reflection data

A seismic refraction/wide‐angle reflection survey for the Trans‐Alaska Crustal Transect program reveals a thin, reflective crust beneath the southern Yukon‐Tanana terrane (YTT) in east central Alaska. These data are the first detailed refraction survey of the southern YTT and compose a 130‐km‐long reversed profile along the Alaska and Richardson highways. Results from this study indicate that low‐
Authors
Bruce C. Beaudoin, Gary S. Fuis, Walter D. Mooney, Warren J. Nokleberg, Nikolas I. Christensen

The canyon system on Mars

Individual Martian equatorial troughs are described, and their stratigraphy, geomorphology and structure are discussed. Possible origins and the overall sequence of events are addressed. Wall rock, interior layered deposits, irregular floor deposits, fractured floor material, and surficial deposits are examined. Chasma walls, wall stability, pits and pit chains, tributary canyons, and the transiti
Authors
Baerbel K. Lucchitta, A. S. McEwen, Gary D. Clow, Paul E. Geissler, R.B. Singer, R. A. Schultz, Steven W. Squyres

Sedimentology, behavior, and hazards of debris flows at Mount Rainier, Washington

Mount Rainier is potentially the most dangerous volcano in the Cascade Range because of its great height, frequent earthquakes, active hydrothermal system, and extensive glacier mantle. Many debris flows and their distal phases have inundated areas far from the volcano during postglacial time. Two types of debris flows, cohesive and noncohesive, have radically different behavior that relates empir
Authors
Kevin M. Scott, Patrick T. Pringle, J.W. Vallance

Fault growth and acoustic emissions in confined granite

The failure process in a brittle granite was studied by using acoustic emission techniques to obtain three dimensional locations of the microfracturing events. During a creep experiment the nucleation of faulting coincided with the onset of tertiary creep, but the development of the fault could not be followed because the failure occurred catastrophically. A technique has been developed that enabl
Authors
David A. Lockner, James D. Byerlee