Publications
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The Loma Prieta, California, earthquake of October 17, 1989: Preseismic observations The Loma Prieta, California, earthquake of October 17, 1989: Preseismic observations
The October 17, 1989, Loma Prieta, Calif., Ms=7.1 earthquake provided the first opportunity in the history of fault monitoring in the United States to gather multidisciplinary preearthquake data in the near field of an M=7 earthquake. The data obtained include observations on seismicity, continuous strain, long-term ground displacement, magnetic field, and hydrology. The papers in this...
Authors
Malcolm J. S. Johnston, Jean A. Olson, David P. Hill, Anthony C. Fraser-Smith, Arman Bernardi, Robert A. Helliwell, Paul R. McGill, O.G. Villard, Robert J. Mueller, Randall A. White, William L. Ellsworth, Evelyn A. Roeloffs, Alan T. Linde, M. T. Gladwin, R. L. Gwyther, R.H.G. Hart, Michael Lisowski, James C. Savage, William H. Prescott, Jerry L. Svarc, Mark Hunter Murray, P.G. Silver, N. J. Valette-Silver, Olga Kolbek
Scanning electron microscope observations of sublimates from Merapi Volcano, Indonesia Scanning electron microscope observations of sublimates from Merapi Volcano, Indonesia
Sublimates were sampled from high-temperature (up to 800°C) fumaroles at Merapi volcano, Indonesia in January 1984. Sampling is accomplished by inserting silica tubes into high-temperature vents. Volcanic gas flows through the tubes and sublimates precipitate on the inner walls in response to the temperature gradient. With decreasing temperature (800–500°C) in the tubes, there are five...
Authors
Robert B. Symonds
Thermodynamic evaluation and restoration of volcanic gas analyses: An example based on modern collection and analytical methods Thermodynamic evaluation and restoration of volcanic gas analyses: An example based on modern collection and analytical methods
Thermodynamic evaluation and restoration procedures are applied to a set of 10 volcanic gas analyses obtained by modern collection and analytical methods. The samples were collected from a vigorously fuming fissure during episode 1 of the Puu Oo eruption of Kilauea Volcano in 1983. A variety of analytical techniques were used to determine the gas compositions. In most samples, the...
Authors
Terrance M. Gerlach
Preventing volcanic catastrophe; the U.S. International Volcano Disaster Assistance Program Preventing volcanic catastrophe; the U.S. International Volcano Disaster Assistance Program
When the seismograph began to record the violent earth-shaking caused by yet another eruption of the Nevado del Ruiz volcano in Colombia, no one thought that a few hours later more than 23,000 people would be dead, killed by lahars (volcanic debris flows) in towns and villages several tens of kilometers away from the volcano. Before the fatal eruption the volcano was being monitored by...
Authors
J.W. Ewert, T.L. Murray, A. B. Lockhart, C.D. Miller
Chemical analyses of pre-Mazama silicic volcanic rocks, inclusions, and glass separates, Crater Lake, Oregon Chemical analyses of pre-Mazama silicic volcanic rocks, inclusions, and glass separates, Crater Lake, Oregon
No abstract available.
Authors
P. E. Bruggman, C. R. Bacon, J. S. Mee, S. T. Pribble, D. F. Siems
Heat flow from four new research drill holes in the Western Cascades, Oregon, U.S.A. Heat flow from four new research drill holes in the Western Cascades, Oregon, U.S.A.
Conceptual models of the thermal structure of the Oregon Cascade Range propose either (1) a narrow zone of magmatic heat sources, flanked by shallow heat-flow anomalies caused by lateral ground-water flow; or (2) a wide zone of magmatic heat sources, with localized, generally negligible ground-water effects. The proposed narrow heat source coincides with the Quaternary volcanic arc...
Authors
S. E. Ingebritsen, M. A. Scholl, D. R. Sherrod
Can rain cause volcanic eruptions? Can rain cause volcanic eruptions?
Volcanic eruptions are renowned for their violence and destructive power. This power comes ultimately from the heat and pressure of molten rock and its contained gases. Therefore we rarely consider the possibility that meteoric phenomena, like rainfall, could promote or inhibit their occurrence. Yet from time to time observers have suggested that weather may affect volcanic activity. In...
Authors
Larry G. Mastin
The danger of collapsing lava domes; lessons for Mount Hood, Oregon The danger of collapsing lava domes; lessons for Mount Hood, Oregon
Nestled in the crater of Oregon's majestic Mount Hood volcano is Crater Rock, a prominent feature known to thousands of skiers, climbers, and tourists who journey each year to the famous Timberline Lodge located high on the volcano's south flank. Crater Rock stands about 100m above the sloping crater floor and warm fumaroles along its base emit sulfur gases and a faint steam plume that...
Authors
S.R. Brantley, W. E. Scott
Dynamics of Kilauea Volcano Dynamics of Kilauea Volcano
One of the longest volcanic eruptions in recorded history began in 1983. Lava flows from Kilauea have since added 120 hectares of new land to the island of Hawaii and covered 100 square kilometres. Kilauea is one of the most thoroughly studied volcanoes in the world. That scrutiny is helping scientists to understand how volcanoes work and to predict where other destructive eruptions...
Authors
J.J. Dvorak, Carl Johnson, Robert I. Tilling
Gravity-driven groundwater flow and slope failure potential: 2. Effects of slope morphology, material properties, and hydraulic heterogeneity Gravity-driven groundwater flow and slope failure potential: 2. Effects of slope morphology, material properties, and hydraulic heterogeneity
Hillslope morphology, material properties, and hydraulic heterogeneities influence the role of groundwater flow in provoking slope instability. We evaluate these influences quantitatively by employing the elastic effective stress model and Coulomb failure potential concept described in our companion paper (Iverson and Reid, this issue). Sensitivity analyses show that of four...
Authors
Mark E. Reid, Richard M. Iverson
Morphology of the island of Hawaii Morphology of the island of Hawaii
Digital elevation data for the island of Hawaii from the U.S. Geographical Survey gridded at 30 m spacing was used to generate a slope map, a shaded relief map, and plots that compare slope and elevation for each of the five volcanoes that compose the island.These computer- generated products are useful in analyzing the morphology of the sland. The volcanoes become steeper with...
Authors
James G. Moore, Robert K. Mark
Spatial and temporal distribution of shallow landsliding during intense rainfall, southeastern Oahu, Hawaii Spatial and temporal distribution of shallow landsliding during intense rainfall, southeastern Oahu, Hawaii
No abstract available.
Authors
Thomas C. Pierson, Richard M. Iverson, Stephen D. Ellen