Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 7487

Effects of major storms on Pacific Islands Effects of major storms on Pacific Islands

Tropical storms of various kinds are as much a depositional event as an erosional event. Much attention is given to the destructive aspects of major storms because of the loss of life and property, but little is known about their beneficial effects to coastal accretion. While we can usually measure and map the instantaneous effects of a tropical storm, we can only speculate about the...
Authors
Bruce Richmond

Landslide susceptibility in the Tully Valley area, Finger Lakes region, New York Landslide susceptibility in the Tully Valley area, Finger Lakes region, New York

As a consequence of a large landslide in the Tully Valley, Onondaga County, New York, an investigation was undertaken to determine the factors responsible for the landslide in order to develop a model for regional landslide susceptibility. The April 27, 1993 Tully Valley landslide occurred within glacial lake clays overlain by till and colluvium on gentle slopes of 9-12 degrees. The...
Authors
Stefan Jager, Gerald E. Wieczorek

An experiment to detect and locate lightning associated with eruptions of Redoubt Volcano An experiment to detect and locate lightning associated with eruptions of Redoubt Volcano

A commercially-available lightning-detection system was temporarily deployed near Cook Inlet, Alaska in an attempt to remotely monitor volcanogenic lightning associated with eruptions of Redoubt Volcano. The system became operational on February 14, 1990; lightning was detected in 11 and located in 9 of the 13 subsequent eruptions. The lightning was generated by ash clouds rising from...
Authors
R. Hoblitt

Explosive tephra emissions of Mount St. Helens, 1989-1991: the violent escape of magmatic gas following storms? Explosive tephra emissions of Mount St. Helens, 1989-1991: the violent escape of magmatic gas following storms?

From 24 August 1989 until 18 June 1991, Mount St. Helens produced at least 28 shallow, explosion-like seismic events with signatures similar to those produced by gas explosions on the dome during the mid 1980s. At least six were accompanied by violent emission of non-juvenile tephra, ejection of blocks of rock nearly 1 km from the vent, and avalanching of debris off the north side of the...
Authors
L.G. Mastin

Emplacement and inflation of pahoehoe sheet flows: observations and measurements of active lava flows on Kilauea volcano, Hawaii Emplacement and inflation of pahoehoe sheet flows: observations and measurements of active lava flows on Kilauea volcano, Hawaii

Inflated pahoehoe sheet flows have a distinctive horizontal upper surface, which can be several hundred meters across, and are bounded to steep monoclinal uplifts. The inflated sheet flows studied ranged from 1 to 5 m in thickness, but initially propagated as thin sheets of fluid pahoehoe lava, generally 20-30 cm thick. The morphology of the lava as flow advanced is described. Inflated...
Authors
K. Hon, J. Kauahikaua, R. Denlinger, K. Mackay

Origin of phenocrysts and compositional diversity in pre-Mazama rhyodacite lavas, Crater Lake, Oregon Origin of phenocrysts and compositional diversity in pre-Mazama rhyodacite lavas, Crater Lake, Oregon

Phenocrysts in porphyritic volcanic rocks may originate in a variety of ways in addition to nucleation and growth in the matrix in which they are found. Porphyritic rhyodacite lavas that underlie the eastern half of Mount Mazama, the High Cascade andesite/dacite volcano that contains Crater Lake caldera, contain evidence that bears on the general problem of phenocryst origin. Phenocrysts...
Authors
S. Nakada, C. R. Bacon, A.E. Gartner

Potential effects of the Hawaii Geothermal Project on ground-water resources on the island of Hawaii Potential effects of the Hawaii Geothermal Project on ground-water resources on the island of Hawaii

In 1990, the State of Hawaii proposed the Hawaii Geothermal Project for the development of as much as 500 MW of electric power from the geothermal system in the East Rift Zone of Kilauea Volcano. This report uses data from 31 wells and 8 springs to describe the properties of the ground-water system in and adjacent to the East Rift Zone. Potential effects of this project on ground-water...
Authors
M.L. Sorey, E.M. Colvard

Dissolved volatile concentrations in an ore-forming magma Dissolved volatile concentrations in an ore-forming magma

Infrared spectroscopic measurements of glass inclusions within quartz phenocrysts from the Plinian fallout of the 22 Ma tuff of Pine Grove show that the trapped silicate melt contained high concentrations of H2O and CO2. Intrusive porphyries from the Pine Grove system are nearly identical in age, composition, and mineralogy to the tephra, and some contain high-grade Mo mineralization...
Authors
J. B. Lowenstern
Was this page helpful?