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Publications

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Triton's geyser-like plumes: Discovery and basic characterization

At least four active geyser-like eruptions were discovered in Voyager 2 images of Triton, Neptune's large satellite. The two best documented eruptions occur as columns of dark material rising to an altitude of about 8 kilometers where dark clouds of material are left suspended to drift downwind over 100 kilometers. The radii of the rising columns appear to be in the range of several tens of meters
Authors
Laurence A. Soderblom, S. W. Kieffer, T.L. Becker, R. H. Brown, A.F. Cook, C.J. Hansen, T. V. Johnson, Randolph L. Kirk, E.M. Shoemaker

Volcanism in Northwest Ishtar Terra, Venus

Soviet Venera 15/16 radar images and topographic data for an area in NW Ishtar Terra, Venus (74°N, 313°E) contain evidence for the existence of a complex volcanic center. Located at the intersection of Akna and Freyja Montes (both elevated ∼4 to 7 km above the planetary reference radius of 6051 km), this volcanic center has a complex caldera system, possibly more than one major eruptive vent, and
Authors
Lisa R. Gaddis, Ronald Greeley

Dark materials in Valles Marineris: Indications of the style of volcanism and magmatism on Mars

Rifting on the equatorial canyon system of Valles Marineris provides a unique view of the interior of the Martian crust to depths reaching 7 km, exposing several in situ bedrock units which testify to past volcanic and magmatic processes on Mars. A thick, regionally extensive deposit observed in Coprates and Juventae chasmata is interpreted on the basis of spectral reflectance, erosional morpholog
Authors
Paul E. Geissler, Robert B. Singer, Baerbel K. Lucchitta

Landslide processes in saprolitic soils of a tropical rain forest, Puerto Rico

Shallow soil slips, earth and debris slides appear to be a primary mechanism of hillslope denudation in the rainforest of eastern Puerto Rico. Annual rainfall in excess of 4,000 mm, and thick sequences (up to 20 m) of residual soils (saprolite) combine to produce these landslides. Shear strength testing and observatons of tension cracks indicate that landslides may start as tensile failure of sapr
Authors
Matthew C. Larsen, Andrew Simon

Rainfall-soil moisture relations in landslide-prone areas of a tropical rain forest, Puerto Rico

Soil moisture conditions are not well documented in steep, tropical landslide-prone terrain. In the 11,330 ha Caribbean National Forest (CNF) in northeastern Puerto Rico more than 170 landslides that occurred from one to approximately 60 years ago have been mapped. Most of these landslides are shallow, with failure depths of 0.5 ot 7 m, and are associated with periods of intense, prolonged rainfal
Authors
Matthew C. Larsen, Angel J. Torres-Sanchez

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° inclinati
Authors
Martitia Tuttle, Patience Cowie, John Tinsley, Michael Benett, John Berrill

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 include a l
Authors
Donna Eberhart-Phillips, Victor F. Labson, William D. Stanley, Andrew J. Michael, Brian D. Rodriguez

Flank tectonics of Martian volcanoes

On the flanks of Olympus Mons is a series of terraces, concentrically distributed around the caldera. Their morphology and location suggest that they could be thrust faults caused by compressional failure of the cone. In an attempt to understand the mechanism of faulting and the possible influences of the interior structure of Olympus Mons, we have constructed a numerical model for elastic stresse
Authors
Paul Thomas, Steven W. Squyres, M. H. Carr

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

Ground motion

No abstract available.
Authors
Roger D. Borcherdt, N. C. Donovan, Mehmet Çelebi, A. Shakal, M. Huang, M. Reichle, C. Ventura, T. Cao, R. Bherburne, M. Savage, Robert B. Darragh, C. Petersen, David Boore, W. B. Joyner, E. V. Leyendecker, P. C. Thenhaus, Kimberly W. Campo, Margaret G. Hopper, S.L. Hanson, S. T. Algermissen, David M. Perkins, Susan E. Hough, D. Simpson, A. Lerner-Lam, P.A. Friberg, R. Busby, L. Shengold, M. Tuttle, Edward H. Field, K.H. Jacob, J. Pacheco, C. Estabrook, M. Peterson, D. H. Johnson, Arthur Frankel

Suggested nomenclature for landslides

The IAEG Commission on Landslides and other Mass Movements on Slopes has proposed English and French names for 19 identifiable features of slope movements and for 7 dimensions of those features. The Commission intends to publish this list in other languages and to supplement and revise it from time to time.
Authors
D.M. Cruden, S. Novograd, G.A. Pilot, E. Krauter, R.K. Bhandari, V. Cotecchia, H. Nakamura, C.O. Okagbue, Zhang Zhuoyuan, J.N. Hutchinson, D. J. Varnes, G.I. Ter-Stepanian

A suggested method for reporting a landslide

The Landslide Report is a Suggested Method developed by the International Geotechnical Societies' UNESCO Working Party on World Landslide Inventory for reporting the position, date, type, geometry, volume and damage of significant landslides.
Authors
Robin Fell, W. Lacerda, D.M. Cruden, S.G. Evans, P. LaRochelle, Fernando Martinez, Lisandro Beltran, J. Jesenak, S. Novograd, E. Krauter, E. Slunga, G.A. Pilot, E.W. Brand, J. Farkas, R.K. Bhandari, V. Cotecchia, Franco Esu, H. Fujita, H. Nakamura, K. Sassa, W.H. Ting, Graham Salt, Nilmar Janbu, A.M. Nespak, Wang Gongxian, Zhang Zhuoyuan, R. Michelena, Mihai Popescu, Leif Viberg, C. Bonnard, J.N. Hutchinson, H.H. Einstein, R. L. Schuster, D. J. Varnes, Z.G. Ter-Martiros­ian, G.I. Ter-Stepanian, P. Anagnosti, M. Hashizume, Masayuki Watanabe