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P.L. Ward

Publications and source records attributed to P.L. Ward.

5 recordsLinked to original sources
USGS2011

Geophysics at Katmai: Geophysical expedition to Novarupta Volcano, Katmai National Park, Alaska

The great eruption of 1912 in the Aleutian Range of Alaska (Figure 1) is exceptional for both its size and relative simplicity. It was the largest eruption of this century and the largest rhyolitic outburst in almost 20 centuries. The 60-hour, 30-km 3 (ejecta volume) eruption produced extensive fallout deposits, an ash-flow sheet that gave rise to the Valley of Ten Thousand Smokes, and the 3-km-diameter Mt. Katmai caldera. Because magma reached the surface through uniform nonvolcanic basement and the vent underwent little or no collapse (unusual for such a large event), the site provides an ideal target for surface geophysical and subsurface coring exploration of structures and conditions produced by explosive volcanism [Panel on Volcanic Studies at Katmai, 1989]. A project to investigate upper crustal magmatic processes at Katmai is part of the U.S. Continental Scientific Drilling Program [Eichelberger and Hildreth, 1986]. The surface studies phase of this project was undertaken last summer and preliminary results are now emerging.

Alaska↗
USGS1990

Global data collection and the surveillance of active volcanoes

Data relay systems on existing earth-orbiting satellites provide an inexpensive way to collect environmental data from numerous remote sites around the world. This technology could be used effectively for fundamental monitoring of most of the world's active volcanoes. Such global monitoring would focus attention on the most dangerous volcanoes that are likely to significantly impact the geosphere and the biosphere.

Palaeogeography, Palaeoclimatology, Palaeoecology↗
USGS1978

Volunteers in the earthquake hazard reduction program

One of the specific objectives of the Earthquake Hazard Reduction Act of 1977 is to educate the public, including State and local officials, about earthquakes. Although the Federal Government is significantly increasing its research efforts in earthquake studies, the ultimate benefits of this program will depend on whether the individual citizen living in an earthquake zone can accurately understand what is meant by an earthquake hazard. With this in mind, I organized a small workshop for approximately 30 people on February 2 and 3, 1978, in Menlo Park, Calif. the purpose of the meeting was to discuss methods of involving volunteers in a meaningful way in earthquake research and in educating the public about earthquake hazards. The emphasis was on earthquake prediction research, but the discussions covered the whole earthquake hazard reduction program. Representatives attended from the earthquake research community, from groups doing socioeconomic research on earthquake matters, and from a wide variety of organizations who might sponsor volunteers.

Earthquake Information Bulletin (USGS)↗
USGS1974

A prototype global volcano surveillance system monitoring seismic activity and tilt

The Earth Resources Technology Satellite makes it feasible for the first time to monitor the level of activity at widely separated volcanoes and to relay these data almost instantancously to one central office. This capability opens a new era in volcanology where the hundreds of normally quiescent but potentially dangerous volcanoes near populated regions around the world can be economically and reliably monitored. A prototype global volcano surveillance system has been established beginning in the fall of 1972 with the help of local scientists on 15 volcanoes in Alaska, Hawaii, Washington, California, Iceland. Guatemala, El Salvador, and Nicaragua. Data on earthquake activity and ground tilt are received 6 to 10 times daily in Menlo Park, California, within 90 minutes of transmission from the sites. Seismic event counters were installed at 19 locations with biaxial borehole tiltineters with 1 microradian sensitivity installed at seven sites. Direct comparison of seismic events that are counted with records from nearby seismic stations show the event counters work quite reliably. An order of magnitude increase in seismic events was observed prior to the eruption of Volcán Fuego in Guatemala in February, 1973. Significant changes in tilt were observed on volcanoes Kilauea. Fuego, and Pacava. This study demonstrates the technological and economic feasibility of utilizing such a volcano surveillance system throughout the world.

Bulletin Volcanologique↗