Publications
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The critical role of volcano monitoring in risk reduction The critical role of volcano monitoring in risk reduction
Data from volcano-monitoring studies constitute the only scientifically valid basis for short-term forecasts of a future eruption, or of possible changes during an ongoing eruption. Thus, in any effective hazards-mitigation program, a basic strategy in reducing volcano risk is the initiation or augmentation of volcano monitoring at historically active volcanoes and also at geologically...
Authors
R.I. Tilling
Variability of passive gas emissions, seismicity, and deformation during crater lake growth at White Island Volcano, New Zealand, 2002-2006 Variability of passive gas emissions, seismicity, and deformation during crater lake growth at White Island Volcano, New Zealand, 2002-2006
We report on 4 years of airborne measurements of CO2, SO2, and H2S emission rates during a quiescent period at White Island volcano, New Zealand, beginning in 2003. During this time a significant crater lake emerged, allowing scrubbig processes to be investigated. CO2 emissions varied from a baseline of 250 to >2000 t d-1 and demonstrated clear annual cycling that was consistent with...
Authors
C. Werner, T. Hurst, B. Scott, S. Sherburn, B.W. Christenson, K. Britten, J. Cole-Baker, B. Mullan
The role of shear and tensile failure in dynamically triggered landslides The role of shear and tensile failure in dynamically triggered landslides
Dynamic stresses generated by earthquakes can trigger landslides. Current methods of landslide analysis such as pseudo-static analysis and Newmark's method focus on the effects of earthquake accelerations on the landslide mass to characterize dynamic landslide behaviour. One limitation of these methods is their use Mohr-Coulomb failure criteria, which only accounts for shear failure, but...
Authors
T.L. Gipprich, R.K. Snieder, R.W. Jibson, W. Kimman
A comparative analysis of simulated and observed landslide locations triggered by Hurricane Camille in Nelson County, Virginia A comparative analysis of simulated and observed landslide locations triggered by Hurricane Camille in Nelson County, Virginia
In 1969, Nelson County, Virginia received up to 71 cm of rain within 12 h starting at 7 p.m. on August 19. The total rainfall from the storm exceeded the 1000-year return period in the region. Several thousands of landslides were induced by rainfall associated with Hurricane Camille causing fatalities and destroying infrastructure. We apply a distributed transient response model for...
Authors
M.M. Morrissey, G. F. Wieczorek, B. A. Morgan
Dependence of displacement-length scaling relations for fractures and deformation bands on the volumetric changes across them Dependence of displacement-length scaling relations for fractures and deformation bands on the volumetric changes across them
Displacement–length data from faults, joints, veins, igneous dikes, shear deformation bands, and compaction bands define two groups. The first group, having a power-law scaling relation with a slope of n = 1 and therefore a linear dependence of maximum displacement and discontinuity length (Dmax = γL), comprises faults and shear (non-compactional or non-dilational) deformation bands...
Authors
Richard A. Schultz, Roger Soliva, Haakon Fossen, Chris Okubo, Donald M. Reeves
Dunes on Titan observed by Cassini Radar Dunes on Titan observed by Cassini Radar
Thousands of longitudinal dunes have recently been discovered by the Titan Radar Mapper on the surface of Titan. These are found mainly within ±30° of the equator in optically-, near-infrared-, and radar-dark regions, indicating a strong proportion of organics, and cover well over 5% of Titan's surface. Their longitudinal duneform, interactions with topography, and correlation with other...
Authors
J. Radebaugh, R. D. Lorenz, J. I. Lunine, S. D. Wall, G. Boubin, E. Reffet, Randolph L. Kirk, R.M. Lopes, E. R. Stofan, Laurence A. Soderblom, M. Allison, M. Janssen, P. Paillou, P. Callahan, Carl Spencer
Permeability of continental crust influenced by internal and external forcing Permeability of continental crust influenced by internal and external forcing
The permeability of continental crust is so highly variable that it is often considered to defy systematic characterization. However, despite this variability, some order has been gleaned from globally compiled data. What accounts for the apparent coherence of mean permeability in the continental crust (and permeability–depth relations) on a very large scale? Here we argue that large...
Authors
S.A. Rojstaczer, S. E. Ingebritsen, D.O. Hayba
Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan
Cassini's third and fourth radar flybys, T7 and T8, covered diverse terrains in the high southern and equatorial latitudes, respectively. The T7 synthetic aperture radar (SAR) swath is somewhat more straightforward to understand in terms of a progressive poleward descent from a high, dissected, and partly hilly terrain down to a low flat plain with embayments and deposits suggestive of...
Authors
J. I. Lunine, C. Elachi, S. D. Wall, M.A. Janssen, M.D. Allison, Y. Anderson, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Franceschetti, Y. Gim, G. Hamilton, S. Hensley, W.T.K. Johnson, K. Kelleher, Randolph L. Kirk, R.M. Lopes, R. Lorenz, D.O. Muhleman, R. Orosei, S.J. Ostro, F. Paganelli, P. Paillou, G. Picardi, F. Posa, J. Radebaugh, L.E. Roth, R. Seu, S. Shaffer, Laurence A. Soderblom, B. Stiles, E. R. Stofan, S. Vetrella, R. West, C. A. Wood, L. Wye, H. Zebker, G. Alberti, E. Karkoschka, B. Rizk, E. McFarlane, C. See, B. Kazeminejad
Rare measurements of a sprite with halo event driven by a negative lightning discharge over Argentina Rare measurements of a sprite with halo event driven by a negative lightning discharge over Argentina
As part of a collaborative campaign to investigate Transient Lummous Events (TLEs) over South America, coordinated optical, ELF/VLF, and lightning measurements were made of a mesoscale thunderstorm observed on February 22-23, 2006 over northern Argentina that produced 445 TLEs within a ???6 hour period. Here, we report comprehensive measurements of one of these events, a sprite with halo...
Authors
M.J. Taylor, M.A. Bailey, P.D. Pautet, S.A. Cummer, N. Jaugey, J.N. Thomas, N.N. Solorzano, Sabbas F. Sao, R.H. Holzworth, O. Pinto, N.J. Schuch
Correlation of the Deccan and Rajahmundry Trap lavas: Are these the longest and largest lava flows on Earth? Correlation of the Deccan and Rajahmundry Trap lavas: Are these the longest and largest lava flows on Earth?
We propose that the Rajahmundry Trap lavas, found near the east coast of peninsular India,are remnants of the longest lava flows yet recognized on Earth (∼ 1000 km long). These outlying Deccan-like lavas are shown to belong to the main Deccan Traps. Several previous studies have already suggested this correlation, but have not demonstrated it categorically. The exposed Rajahmundry lavas...
Authors
Stephen Self, Anne E. Jay, Michael Widdowson, Laszlo P. Keszthelyi
Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades
Medicine Lake Volcano (MLV), located in the southern Cascades ∼ 55 km east-northeast of contemporaneous Mount Shasta, has been found by exploratory geothermal drilling to have a surprisingly silicic core mantled by mafic lavas. This unexpected result is very different from the long-held view derived from previous mapping of exposed geology that MLV is a dominantly basaltic shield volcano...
Authors
Julie M. Donnelly-Nolan, Timothy L. Grove, M. A. Lanphere, Duane E. Champion, David W. Ramsey
Atmospheric contribution of gas emissions from Augustine volcano, Alaska during the 2006 eruption Atmospheric contribution of gas emissions from Augustine volcano, Alaska during the 2006 eruption
Airborne surveillance of gas emissions from Augustine for SO2, CO2 and H2S showed no evidence of anomalous degassing from 1990 through May 2005. By December 20, 2005, Augustine was degassing 660 td−1 of SO2, and ten times that by January 4, 2006. The highest SO2 emission rate measured during the 2006 eruption was 8650 td−1 (March 1); for CO2, 13000 td−1 (March 9), and H2S, 8 td−1...
Authors
K.A. McGee, M.P. Doukas, R. G. McGimsey, C.A. Neal, R.L. Wessels