Publications
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Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania
As a comparison to airborne infrared (IR) flux measurements, ground-based sampling of fumarole and soil gases was used to characterize the quiescent degassing of CO2 from Oldoinyo Lengai volcano. Aerial and ground-based measurements are in good agreement: ∼75% of the aerially measured CO2 flux at Lengai (0.05–0.06 × 1012 mol yr−1 or 6000–7200 tonnes CO2 d−1) can be attributed to seven...
Authors
K.W. Koepenick, S.L. Brantley, J. M. Thompson, G.L. Rowe, A.A. Nyblade, C. Moshy
Earthquake technology fights crime Earthquake technology fights crime
Scientists with the U.S. Geological Survey have adapted their methods for quickly finding the exact source of an earthquake to the problem of locating gunshots. On the basis of this work, a private company is now testing an automated gunshot-locating system in a San Francisco Bay area community. This system allows police to rapidly pinpoint and respond to illegal gunfire, helping to...
Authors
John C. Lahr, Peter L. Ward, Peter H. Stauffer, James W. Hendley
Photographs of the 1989-90 eruptions of Redoubt Volcano, Alaska Photographs of the 1989-90 eruptions of Redoubt Volcano, Alaska
No abstract available.
Authors
A.L. Roach, Christina A. Neal, R. G. McGimsey
Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan
This study investigates 31 years of fumarole gas and condensate (trace elements) data from Showa-Shinzan, a dacitic dome-cryptodome complex that formed during the 1943-1945 eruption of Usu volcano. Forty-two gas samples were collected from the highest-temperature fumarole, named A-1, from 1954 (800??C) to 1985 (336??C), and from lower-temperature vents. Condensates were collected...
Authors
R.B. Symonds, Y. Mizutani, Paul H. Briggs
Data base of impact craters on Venus based on analysis of Magellan radar images and altimetry data Data base of impact craters on Venus based on analysis of Magellan radar images and altimetry data
No abstract available.
Authors
Gerald G. Schaber, Randolph L. Kirk, Robert G. Strom
Aeromagnetic map of the Clear Lake region on parts of the Santa Rosa and Ukih 1° by 2° quadrangles, California Aeromagnetic map of the Clear Lake region on parts of the Santa Rosa and Ukih 1° by 2° quadrangles, California
No abstract available.
Authors
Water Resources Division U.S. Geological Survey
Water on early Mars Water on early Mars
Large flood channels, valley networks and a variety of features attributed to the action of ground ice indicate that Mars emerged from heavy bombardment 3.8 Ga ago, with an inventory of water at the surface equivalent to at least a few hundred metres spread over the whole planet, as compared with 3 km for the Earth. The mantle of Mars is much drier than that of the Earth, possibly as a...
Authors
Michael D. Carr
A migratory mantle plume on Venus: Implications for Earth? A migratory mantle plume on Venus: Implications for Earth?
A spatially fixed or at least internally rigid hotspot reference frame has been assumed for determining relative plate motions on Earth. Recent 1:5,000,000 scale mapping of Venus, a planet without terrestrial-style plate tectonics and ocean cover, reveals a systematic age and dimensional progression of corona-like arachnoids occurring in an uncinate chain. The nonrandom associations...
Authors
Mary G. Chapman, Randolph L. Kirk
Aeromagnetic survey over US to advance geomagnetic research Aeromagnetic survey over US to advance geomagnetic research
A proposed high-altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic-anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER-2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The...
Authors
T.G. Hildenbrand, R.J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
The initial cooling of pahoehoe flow lobes The initial cooling of pahoehoe flow lobes
In this paper we describe a new thermal model for the initial cooling of pahoehoe lava flows. The accurate modeling of this initial cooling is important for understanding the formation of the distinctive surface textures on pahoehoe lava flows as well as being the first step in modeling such key pahoehoe emplacement processes as lava flow inflation and lava tube formation. This model is
Authors
L. Keszthelyi, R. Denlinger
Channel adjustment of an unstable coarse-grained stream: Opposing trends of boundary and critical shear stress, and the applicability of extremal hypotheses Channel adjustment of an unstable coarse-grained stream: Opposing trends of boundary and critical shear stress, and the applicability of extremal hypotheses
Channel adjustments in the North Fork Toutle River and the Toutle River main stem were initiated by deposition of a 2.5km3 debris avalanche and associated lahars that accompanied the catastrophic eruption of Mount St. Helens, Washington on 18 May 1980. Channel widening was the dominant process. In combination, adjustments caused average boundary shear stress to decrease non-linearly with...
Authors
Andrew Simon, Colin R. Thorne
Characteristics of the continental slope and rise off North Carolina from GLORIA and seismic-reflection data: The interaction of downslope and contour current processes Characteristics of the continental slope and rise off North Carolina from GLORIA and seismic-reflection data: The interaction of downslope and contour current processes
No abstract available.
Authors
Peter Popenoe, William P. Dillon