Publications
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Regional correlation of Grande Ronde basalt flows, Columbia River basalt group, Washington, Oregon, and Idaho (USA)
The tholeiitic flood basalts of the Columbia River Basalt Group of middle and late Miocene age cover more than 200,000 km2 in Washington, Oregon, and Idaho. The most voluminous formation of the Group, the Grande Ronde Basalt, erupted for 2 m.y. from north-northwest-trending fissure systems concentrated in southeast Washington and adjacent Oregon and Idaho. Four magnetostratigraphic units (designat
Authors
Margaret T. Mangan, Thomas L. Wright, Don Swanson, G. R. Byerly
An assessment of ground-nest depredation in a catastrophically disturbed region, Mount St. Helens, Washington
The explosive eruption of the Mount St. Helens volcano on 18 May 1980 severely affected a large ar- ray of plant and animal populations (Edwards and Schwartz 1981, MacMahon 1982, Wissmar et al. 1982) over a vast area (>600 kM2) (Fig. 1). Volcanic eruptions are relatively common agents of large-scale biotic disturbance, yet few studies have addressed either short- or long-term effects on avian popu
Authors
Douglas C. Andersen, James A. MacMahon
Age of -360-m reef terrace, Hawaii, and the rate of late Pleistocene subsidence of the island
Observations from a manned submersible vehicle indicate that the −360-m reef terrace northwest of the island of Hawaii is a drowned coral reef. The preferred uranium-series age of coralline algae collected from the reef face is 120 ± 5 ka. This age agrees with the notion that the reef was drowned during the sea-level rise following the major lowstand of the sea that occurred at 145 ka (oxygen isot
Authors
B. J. Szabo, James G. Moore
Unsteady, nonuniform landslide motion: 2. Linearized theory and the kinematics of transient response
Unsteady, nonuniform landslide motion is caused by temporal and spatial variations in driving and resisting forces. Common sources of these variations include stream undercutting of landslide toes, episodic headscarp slumping, and ground-water potentiometric fluctuations. A linear theory for the kinematics of unsteady, nonuniform landslide motion is developed here by analyzing the behavior of smal
Authors
Richard M. Iverson
Volcano monitoring at the U.S. Geological Survey's Hawaiian Volcano Observatory
The island of Hawaii has one of the youngest landscapes on Earth, formed by frequent addition of new lava to its surface. Because Hawaiian are generally nonexplosive and easily accessible, the island has long attracted geologists interested in studying the extraordinary power of volcanic eruptions. The U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), now nearing its 75th anniversary.
Authors
Christina C. Heliker, J. D. Griggs, T. Jane Takahashi, Thomas L. Wright
Miocene silicoflagellates from Chatham Rise, Deep Sea Drilling Project Site 594
Miocene silicoflagellates, dominated by Mesocena, are identified and correlated from Site 594 to other Deep Sea Drilling Project sites. Relative paleotemperature values from silicoflagellates at Site 594 are very low, supporting the evidence of the associated cold-water, low-diversity Coccolith assemblages. The greatest abundances of Mesocena diodon nodosa yet recorded occur at Site 594, which is
Authors
David Bukry
World slope map
A colored slope map (scale 1:80,000,000) was generated from digital land and sea floor elevations at 5‐min spacings from data tapes from the National Geophysical Data Center. Slope analysis is facilitated by examining the average slope in 250‐m altitude‐depth intervals both globally and in each of eight tectonic plates. The most striking feature of the map is the multiple parallel bands of steep s
Authors
James G. Moore, R. K. Mark
Hydrothermal minerals and alteration rates at Surtsey volcano, Iceland
The volcanic island Surtsey, off the south coast of Iceland, was created by volcanic activity in 1963–1967. Core from a 181-m-deep hole extending 123 m below sea level shows the results of 12 yr of hydrothermal alteration of basaltic tephra. The primary cause of heating of the tephra and of development of the hydrothermal system was the intrusion of dikes below sea level. At present, the hottest p
Authors
S. P. Jakobsson, James G. Moore
Unsteady, nonuniform landslide motion: 1. Theoretical dynamics and the steady datum state
Unsteady, nonuniform motion of persistently active landslides is a process of widespread importance. A general, three-dimensional theory aimed at elucidating this process is developed from physical principles and field measurements of landslide behavior. The theory employs a versatile constitutive model that represents landslides as deformable bodies composed of frictional, nonlinear viscoplastic
Authors
Richard M. Iverson
Dynamics of slow landslides: a theory for time-dependent behavior
No abstract available.
Authors
Richard M. Iverson
Book review of Slope Instability, D. Brunsden and D.B. Prior, eds., Wiley, New York, 620 p.
No abstract available.
Authors
Richard M. Iverson