Publications
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Airport geomagnetic surveys in the United States Airport geomagnetic surveys in the United States
The Federal Aviation Administration (FAA) and the United States military have requirements for design, location, and construction of compass calibration pads (compass roses), these having been developed through collaboration with US Geological Survey (USGS) personnel. These requirements are detailed in the FAA Advisory Circular AC 150/5300-13, Appendix 4, and in various military...
Authors
A. Berarducci
Sensor web enables rapid response to volcanic activity Sensor web enables rapid response to volcanic activity
Rapid response to the onset of volcanic activity allows for the early assessment of hazard and risk [Tilling, 1989]. Data from remote volcanoes and volcanoes in countries with poor communication infrastructure can only be obtained via remote sensing [Harris et al., 2000]. By linking notifications of activity from ground-based and spacebased systems, these volcanoes can be monitored when...
Authors
Ashley G. Davies, Steve Chien, Robert Wright, Asta Mikijus, Philip R. Kyle, Matt Welsh, Jeffrey B. Johnson, Daniel Tran, Steven R. Schaffer, Robert Sherwood
A volcano bursting at the seams: Inflation, faulting, and eruption at Sierra Negra volcano, Galápagos A volcano bursting at the seams: Inflation, faulting, and eruption at Sierra Negra volcano, Galápagos
The results of geodetic monitoring since 2002 at Sierra Negra volcano in the Galápagos Islands show that the filling and pressurization of an ∼2-km-deep sill eventually led to an eruption that began on 22 October 2005. Continuous global positioning system (CGPS) monitoring measured >2 m of accelerating inflation leading up to the eruption and contributed to nearly 5 m of total uplift...
Authors
William W. Chadwick, Dennis J. Geist, Sigurjon Jonsson, Michael P. Poland, Daniel J. Johnson, Charles M. Meertens
Soil grain analyses at Meridiani Planum, Mars Soil grain analyses at Meridiani Planum, Mars
Grain‐size analyses of the soils at Meridiani Planum have been used to identify rock sources for the grains and provide information about depositional processes under past and current conditions. Basaltic sand, dust, millimeter‐size hematite‐rich spherules interpreted as concretions, spherule fragments, coated partially buried spherules, basalt fragments, sedimentary outcrop fragments...
Authors
C.M. Weitz, R. C. Anderson, J.F. Bell, W. H. Farrand, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, R.V. Morris, S. W. Squyres, R.J. Sullivan
Dynamics of seismogenic volcanic extrusion at Mount St Helens in 2004-05 Dynamics of seismogenic volcanic extrusion at Mount St Helens in 2004-05
The 2004-05 eruption of Mount St Helens exhibited sustained, near-equilibrium behaviour characterized by relatively steady extrusion of a solid dacite plug and nearly periodic shallow earthquakes. Here we present a diverse data set to support our hypothesis that these earthquakes resulted from stick-slip motion along the margins of the plug as it was forced incrementally upwards by...
Authors
R.M. Iverson, D. Dzurisin, C. A. Gardner, T.M. Gerlach, R.G. LaHusen, M. Lisowski, J. J. Major, S. D. Malone, J.A. Messerich, S.C. Moran, J.S. Pallister, A.I. Qamar, S. P. Schilling, J.W. Vallance
Coastal landslide material loss rates associated with severe climatic events Coastal landslide material loss rates associated with severe climatic events
Deep-seated landslides along the California coast deliver large amounts of material to the nearshore littoral environment. Landslide movement, a combined result of slope base undercutting by waves and ground saturation, is highly episodic. Movement occurs primarily during periods of high rainfall and large waves, such as those associated with El Nin??o events. This analysis applies...
Authors
C.J. Hapke, K.R. Green
Two models for evaluating landslide hazards Two models for evaluating landslide hazards
Two alternative procedures for estimating landslide hazards were evaluated using data on topographic digital elevation models (DEMs) and bedrock lithologies in an area adjacent to the Missouri River in Atchison County, Kansas, USA. The two procedures are based on the likelihood ratio model but utilize different assumptions. The empirical likelihood ratio model is based on non-parametric...
Authors
J.C. Davis, C.-J. Chung, G.C. Ohlmacher
Mapping of Titan: Results from the first Titan radar passes Mapping of Titan: Results from the first Titan radar passes
The first two swaths collected by Cassini's Titan Radar Mapper were obtained in October of 2004 (Ta) and February of 2005 (T3). The Ta swath provides evidence for cryovolcanic processes, the possible occurrence of fluvial channels and lakes, and some tectonic activity. The T3 swath has extensive areas of dunes and two large impact craters. We interpret the brightness variations in much...
Authors
E. R. Stofan, J. I. Lunine, R. Lopes, F. Paganelli, R. D. Lorenz, C. A. Wood, Randolph L. Kirk, S. Wall, C. Elachi, Laurence A. Soderblom, S. Ostro, M. Janssen, J. Radebaugh, L. Wye, H. Zebker, Y. Anderson, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W.T.K. Johnson, K. Kelleher, D. Muhleman, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, B. Stiles, S. Vetrella, R. West
Evaluating a small footprint, waveform-resolving lidar over coastal vegetation communities Evaluating a small footprint, waveform-resolving lidar over coastal vegetation communities
NASA’s Experimental Advanced Airborne Research Lidar (EAARL) is a raster-scanning, waveform-resolving, green-wavelength (532 nm) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor records the time history of the return waveform within a small footprint (20 cm diameter) for each laser pulse, enabling characterization of...
Authors
Amar Nayegandhi, John Brock, C. Wayne Wright, M. J. O’Connell
Cosmogenic 3He production rates revisited from evidences of grain size dependent release of matrix-sited helium Cosmogenic 3He production rates revisited from evidences of grain size dependent release of matrix-sited helium
Measurements of the cosmogenic 3He (3Hec) content of various size aliquots of exposed olivines show that the fine fraction (
Authors
P.-H. Blard, R. Pik, J. Lave, D. Bourles, P.G. Burnard, R. Yokochi, B. Marty, F. Trusdell
Titan Radar Mapper observations from Cassini's T3 fly-by Titan Radar Mapper observations from Cassini's T3 fly-by
Cassini's Titan Radar Mapper imaged the surface of Saturn's moon Titan on its February 2005 fly-by (denoted T3), collecting high-resolution synthetic-aperture radar and larger-scale radiometry and scatterometry data. These data provide the first definitive identification of impact craters on the surface of Titan, networks of fluvial channels and surficial dark streaks that may be...
Authors
C. Elachi, S. Wall, M. Janssen, E. Stofan, R. Lopes, Randolph L. Kirk, R. Lorenz, J. Lunine, F. Paganelli, Laurence A. Soderblom, C. Wood, L. Wye, H. Zebker, Y. Anderson, S. Ostro, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W. Johnson, K. Kelleher, D. Muhleman, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, B. Stiles, S. Vetrella, R. West
Volcanic history and 40Ar/39Ar and 14C geochronology of Terceira Island, Azores, Portugal Volcanic history and 40Ar/39Ar and 14C geochronology of Terceira Island, Azores, Portugal
Seven new 40Ar/39Ar and 23 new radiocarbon ages of eruptive units, in support of new geologic mapping, improve the known chronology of Middle to Late Pleistocene and Holocene volcanic activity on the island of Terceira, Azores and define an east-to-west progression in stratovolcano growth. The argon ages indicate that Cinco Picos Volcano, the oldest on Terceira, completed its main...
Authors
Andrew T. Calvert, Richard B. Moore, John P. McGeehin, Antonio Rodrigues da Silva