Publications
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The Breccia Museo formation, Campi Flegrei, southern Italy: Geochronology, chemostratigraphy and relationship with the Campanian Ignimbrite eruption The Breccia Museo formation, Campi Flegrei, southern Italy: Geochronology, chemostratigraphy and relationship with the Campanian Ignimbrite eruption
The Breccia Museo is one of the most debated volcanic formations of the Campi Flegrei volcanic district. The deposit, made up of six distinctive stratigraphic units, has been interpreted by some as the proximal facies of the major caldera-forming Campanian Ignimbrite eruption, and by others as the product of several, more recent, independent and localized events. New geochemical and
Authors
L. Fedele, C. Scarpati, M. Lanphere, L. Melluso, V. Morra, A. Perrotta, G. Ricci
Development of the U.S. Geological Survey's PAGER system (Prompt Assessment of Global Earthquakes for Response) Development of the U.S. Geological Survey's PAGER system (Prompt Assessment of Global Earthquakes for Response)
The Prompt Assessment of Global Earthquakes for Response (PAGER) System plays a primary alerting role for global earthquake disasters as part of the U.S. Geological Survey’s (USGS) response protocol. We provide an overview of the PAGER system, both of its current capabilities and our ongoing research and development. PAGER monitors the USGS’s near real-time U.S. and global earthquake...
Authors
D.J. Wald, P.S. Earle, T.I. Allen, K. Jaiswal, K. Porter, M. Hearne
Modeling rainfall conditions for shallow landsliding in Seattle, Washington Modeling rainfall conditions for shallow landsliding in Seattle, Washington
We describe the results from an application of a distributed, transient infiltration–slope-stability model for an 18 km2 area of southwestern Seattle, Washington, USA. The model (TRIGRS) combines an infinite slope-stability calculation and an analytic, one-dimensional solution for pore-pressure diffusion in a soil layer of finite depth in response to time-varying rainfall. The transient...
Authors
Jonathan W. Godt, William H. Schulz, Rex L. Baum, William Z. Savage
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
A model for radial dike emplacement in composite cones based on observations from Summer Coon volcano, Colorado, USA A model for radial dike emplacement in composite cones based on observations from Summer Coon volcano, Colorado, USA
We mapped the geometry of 13 silicic dikes at Summer Coon, an eroded Oligocene stratovolcano in southern Colorado, to investigate various characteristics of radial dike emplacement in composite volcanoes. Exposed dikes are up to about 7 km in length and have numerous offset segments along their upper peripheries. Surprisingly, most dikes at Summer Coon increase in thickness with distance...
Authors
Michael P. Poland, W.P. Moats, J.H. Fink
Observations of the north polar water ice annulus on Mars using THEMIS and TES Observations of the north polar water ice annulus on Mars using THEMIS and TES
The Martian seasonal CO2 ice caps advance and retreat each year. In the spring, as the CO2 cap gradually retreats, it leaves behind an extensive defrosting zone from the solid CO2 cap to the location where all CO2 frost has sublimated. We have been studying this phenomenon in the north polar region using data from the THermal EMission Imaging System (THEMIS), a visible and infra-red (IR)...
Authors
Kiri L. Wagstaff, Timothy N. Titus, Anton B. Ivanov, Rebecca Castano, Joshua L. Bandfield
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
Collision tectonics of the Central Indian Suture zone as inferred from a deep seismic sounding study Collision tectonics of the Central Indian Suture zone as inferred from a deep seismic sounding study
The Central Indian Suture (CIS) is a mega-shear zone extending for hundreds of kilometers across central India. Reprocessing of deep seismic reflection data acquired across the CIS was carried out using workstation-based commercial software. The data distinctly indicate different reflectivity characteristics northwest and southeast of the CIS. Reflections northwest of the CIS...
Authors
D.M. Mall, P.R. Reddy, Walter D. Mooney
Rainfall-triggered landslides, anthropogenic hazards, and mitigation strategies Rainfall-triggered landslides, anthropogenic hazards, and mitigation strategies
Rainfall-triggered landslides are part of a natural process of hillslope erosion that can result in catastrophic loss of life and extensive property damage in mountainous, densely populated areas. As global population expansion on or near steep hillslopes continues, the human and economic costs associated with landslides will increase. Landslide hazard mitigation strategies generally...
Authors
M. C. Larsen
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
The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe
At the beginning of 2006, the U.S. Geological Survey (USGS) Earthquake Hazards Program (EHP) introduced a new automated Earthquake Notification Service (ENS) to take the place of the National Earthquake Information Center (NEIC) "Bigquake" system and the various other individual EHP e-mail list-servers for separate regions in the United States. These included northern California...
Authors
Lisa A. Wald, David J. Wald, Stan Schwarz, Bruce Presgrave, Paul S. Earle, Eric Martinez, David Oppenheimer
Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits
Hydrothermal alteration at Mount Rainier waxed and waned over the 500,000-year episodic growth of the edifice. Hydrothermal minerals and their stable-isotope compositions in samples collected from outcrop and as clasts from Holocene debris-flow deposits identify three distinct hypogene argillic/advanced argillic hydrothermal environments: magmatic-hydrothermal, steam-heated, and magmatic...
Authors
D. A. John, T. W. Sisson, G. N. Breit, R. O. Rye, J.W. Vallance