Publications

During 1993, the Alaska Volcano Observatory (AVO) responded to episodes of eruptive activity or false alarms at nine volcanic centers in the state of Alaska. Additionally, as part of a formal role in KVERT (the Kamchatkan Volcano Eruption Response Team), AVO staff also responded to eruptions on the Kamchatka Peninsula, details of which are summarized in Miller and Kurianov (1993). In 1993, AVO ma

The U.S. Geological Survey's Cascades Volcano Observatory (CVO) has been testing low-cost, low-power Global Positioning System (GPS) receivers for use in the monitoring of restless volcanoes. Field tests of two single-frequency (L1 only) receivers, the Ashtech SCA-12S and the Leica SR261 show that these units can measure positions precisely enough to meet our monitoring needs. For line lengths up

The U.S. Geological Survey (USGS) is a party to joint interagency Memorandum of Understandings (MOUs) with the Bureau of Land Management (BLM) and the U.S. Bureau of Mines (USBM) to coordinate resource assessments and evaluations of BLM administered lands. Resource assessments of BLM Resource Areas, that are conducted by the USGS under these MOUs, assist the BLM in meeting inventory and evaluation

Earthquake swarms are pervasive at volcanoes, but have seldom been studied systematically. Most swarms that are described in the literature are those that occurred in association with eruptions; indeed, earthquake swarms are the most reliable method of forecasting eruptions. For the purpose of this report, a swarm is defined as many earthquakes of the same size occurring in a small volume. Swarms

We derived high resolution Digital Terrain Models from stereo images of the asteroid Ida that were obtained by the Galileo spacecraft during the flyby in August 1993 and compared these results with terrain models derived from two-dimensional photoclinometry. The comparison shows that there are striking discrepancies between the results from the two models depending on the spatial scale length of s

The Hyogoken-Nanbu (Kobe) earthquake of January 17, 1995 (5:46:52 JST) occurred in an area of complex faulting located near Awaji Island and the Hanshin area of Japan (34.607 N, 135.043 E, depth 14.3 km; Japan Meteorological Agency, JMA). The area which is near the urban centers of Kobe City and Osaka is located about 250 km from the Nankai trough, which forms the boundary between the Philippine S

Landslides cause much damage to property throughout the metropolitan area of Cincinnati, Ohio. Most landslides occur in unconsolidated deposits, including colluvium, till, glacial lake clays, and man-made fill derived from colluvium and glacial deposits. Landslides in thin colluvium are widespread on steeper slopes that wall the valleys of the Ohio River and its tributaries. Abundant landslides al

Thirty-eight hydrothermal minerals were identified from 356 drill-core specimens that were obtained from three Scientific Observation Holes (SOH-1, SOH-2, and SOH-4) drilled along the lower East Rift Zone (ERZ) of Kilauea Volcano, Hawaii. The minerals formed during alteration of basaltic rocks and glass by hot, circulating, waters in aquifers consisting of variable mixtures of meteoric water and s

More than 100 tephra-fall deposits erupted from Mount St. Helens within about the last 40,000 years are grouped into tephra sets and layers distinguished from each other chiefly by differences in mineral composition and age. The tephra deposits record a complex history of the volcano, form important time-stratigraphic markers, and provide information about probable kinds, frequencies, and magnitud

Although inhabited by thousands of people when first reached by Europeans, the Pacific coast of southern Washington has little recognized evidence of prehistoric human occupation. This apparent contradiction may be explained partly by geologic evidence for coastal submergence during prehistoric earthquakes on the Cascadia subduction zone. Recently discovered archaeological sites, exposed in the ba

The FLOW computer model of McEwen and Malin (1989) modified for application to the study of Venus fluidized ejecta blankets (FEBs) demonstrates that relatively low viscosities, yield strengths, and initial velocities are required to duplicate the observed flow paths of the outflow materials. The model calculates the velocities and simulated flow paths of gravity flows over Magellan topography. The

We elaborate on the well-known spatial association between axc volcanoes and Wadati Benioff zones and explore in detail their genetic relationships as dual physical expressions of slab metamorphism of the oceanic crust and uppermost mantle. At hypocentral depths less than 200 km intra slab Wadati-Benioff earthquakes tend to occur near the top surfaces of slabs. Subduction of very young lithosphere