Publications
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Evidence for debris flow gully formation initiated by shallow subsurface water on Mars
The morphologies of some martian gullies appear similar to terrestrial features associated with debris flow initiation, erosion, and deposition. On Earth, debris flows are often triggered by shallow subsurface throughflow of liquid water in slope-mantling colluvium. This flow causes increased levels of pore pressure and thus decreased shear strength, which can lead to slide failure of slope materi
Authors
Nina L. Lanza, Grant A. Meyer, Chris Okubo, Horton E. Newsom, Roger C. Wiens
Lunar Reconnaissance Orbiter Camera (LROC) instrument overview
The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NACs) are on the NASA Lunar Reconnaissance Orbiter (LRO). The WAC is a 7-color push-frame camera (100 and 400 m/pixel visible and UV, respectively), while the two NACs are monochrome narrow-angle linescan imagers (0.5 m/pixel). The primary mission of LRO is to obtain measurements of the Moon that will
Authors
M.S. Robinson, S.M. Brylow, M. Tschimmel, D. Humm, S.J. Lawrence, P. C. Thomas, B.W. Denevi, E. Bowman-Cisneros, J. Zerr, M.A. Ravine, M.A. Caplinger, F.T. Ghaemi, J.A. Schaffner, M. C. Malin, P. Mahanti, A. Bartels, J. Anderson, T.N. Tran, E. M. Eliason, A. S. McEwen, E. Turtle, B.L. Jolliff, H. Hiesinger
The ShakeOut earthquake scenario: Verification of three simulation sets
This paper presents a verification of three simulations of the ShakeOut scenario, an Mw 7.8 earthquake on a portion of the San Andreas fault in southern California, conducted by three different groups at the Southern California Earthquake Center using the SCEC Community Velocity Model for this region. We conducted two simulations using the finite difference method, and one by the finite element me
Authors
J. Bielak, R.W. Graves, K.B. Olsen, R. Taborda, L. Ramirez-Guzman, S.M. Day, G.P. Ely, D. Roten, T.H. Jordan, P.J. Maechling, J. Urbanic, Y. Cui, G. Juve
Monitoring and characterizing natural hazards with satellite InSAR imagery
Interferometric synthetic aperture radar (InSAR) provides an all-weather imaging capability for measuring ground-surface deformation and inferring changes in land surface characteristics. InSAR enables scientists to monitor and characterize hazards posed by volcanic, seismic, and hydrogeologic processes, by landslides and wildfires, and by human activities such as mining and fluid extraction or in
Authors
Zhong Lu, Jixian Zhang, Yonghong Zhang, Daniel Dzurisin
The water table
The water table is a fundamental concept in hydrogeology, yet it is frequently incorrectly defined. For example, both the NGWA (2003) and AGI (Neuendorf et al. 2005) glossaries define the water table as the atmospheric pressure surface that is coincident with the top of the zone of saturation. This definition is also found occasionally in groundwater textbooks as well as in primers, where it is si
Authors
Thomas L. Holzer
Tree-ring dated landslide movements and seismic events in southwestern Montana, USA
Because many tree species can live for several centuries or longer (Brown 1996), tree-ring analysis can be a valuable tool to date geomorphic events such as landslides, earthquakes, and avalanches in regions lacking long historical records. Typically, a catastrophic landslide will destroy all trees on the landslide, but trees on slower moving landslides may survive. For example, the Slumgullion ea
Authors
Paul E. Carrara, J. Michael O'Neill
Passive seismic monitoring of natural and induced earthquakes: Case studies, future directions and socio-economic relevance
An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays is a widely used technique that has been successfully appli
Authors
Marco Bohnhoff, Georg Dresen, William L. Ellsworth, Hisao Ito
Estimating the empirical probability of submarine landslide occurrence
The empirical probability for the occurrence of submarine landslides at a given location can be estimated from age dates of past landslides. In this study, tools developed to estimate earthquake probability from paleoseismic horizons are adapted to estimate submarine landslide probability. In both types of estimates, one has to account for the uncertainty associated with age-dating individual even
Authors
Eric L. Geist, Thomas E. Parsons
Top of head scarp and internal scarps for landslide deposits in the Little North Santiam River Basin, Oregon
Data points represent head scarps, flank scarps, and minor internal scarps (linear) associated with landslide deposits in the Little North Santiam River Basin, Oregon. This work was completed as part of the Master's thesis "Turbidity Monitoring and LiDAR Imagery Indicate Landslides are Primary Source of Suspended-Sediment Load in the Little North Santiam River Basin, Oregon, Winter 2009-2010" by S
Authors
Steven Sobieszczyk
Location of photographs showing landslide features in the Little North Santiam River Basin, Oregon
Data points represent locations of photographs taken of landslides in the Little North Santiam River Basin, Oregon. Photos were taken in spring of 2010 during field verification of landslide locations (deposits previously mapped using LiDAR-derived imagery). The photographs depict various landslide features, such as scarps, pistol-butt trees, or colluvium deposits. This work was completed as part
Authors
Steven Sobieszczyk
Landslide inventory for the Little North Santiam River Basin, Oregon
This geodatabase is an inventory of existing landslides in the Little North Santiam River Basin, Oregon (2009). Each landslide feature shown has been classified according to a number of specific characteristics identified at the time recorded in the GIS database. The classification scheme was developed by the Oregon Department of Geology and Mineral Industries (Burns and Madin, 2009). Several sig
Authors
Steven Sobieszczyk
Head scarp boundary for the landslides in the Little North Santiam River Basin, Oregon
Polygons represent head scarps and flank scarps associated with landslide deposits in the Little North Santiam River Basin, Oregon. This work was completed as part of the Master's thesis "Turbidity Monitoring and LiDAR Imagery Indicate Landslides are Primary Source of Suspended-Sediment Load in the Little North Santiam River Basin, Oregon, Winter 2009-2010" by Steven Sobieszczyk, Portland State Un
Authors
Steven Sobieszczyk