Publications
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Channel morphometry, sediment transport, and implications for tectonic activity and surficial ages of Titan basins Channel morphometry, sediment transport, and implications for tectonic activity and surficial ages of Titan basins
Fluvial features on Titan and drainage basins on Earth are remarkably similar despite differences in gravity and surface composition. We determined network bifurcation (Rb) ratios for five Titan and three terrestrial analog basins. Tectonically-modified Earth basins have Rb values greater than the expected range (3.0–5.0) for dendritic networks; comparisons with Rb values determined for...
Authors
R. Cartwright, J.A. Clayton, Randolph L. Kirk
Opportunity Mars Rover mission: Overview and selected results from Purgatory ripple to traverses to Endeavour crater Opportunity Mars Rover mission: Overview and selected results from Purgatory ripple to traverses to Endeavour crater
Opportunity has been traversing the Meridiani plains since 25 January 2004 (sol 1), acquiring numerous observations of the atmosphere, soils, and rocks. This paper provides an overview of key discoveries between sols 511 and 2300, complementing earlier papers covering results from the initial phases of the mission. Key new results include (1) atmospheric argon measurements that...
Authors
R. E. Arvidson, James W. Ashley, J.F. Bell, M. Chojnacki, J. Cohen, T.E. Economou, W. H. Farrand, Robin L. Fergason, I. Fleischer, Paul E. Geissler, Ralf Gellert, M.P. Golombek, J.P. Grotzinger, E.A. Guinness, R.M. Haberle, Kenneth E. Herkenhoff, J.A. Herman, K.D. Iagnemma, B.L. Jolliff, J. R. Johnson, G. Klingelhofer, A.H. Knoll, A.T. Knudson, R. Li, S. M. McLennan, D. W. Mittlefehldt, R.V. Morris, T. J. Parker, M.S. Rice, C. Schroder, Laurence A. Soderblom, S. W. Squyres, R.J. Sullivan, M.J. Wolff
Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars
Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light‐toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous...
Authors
J.J. Wray, R.E. Milliken, Colin M. Dundas, Gregg A. Swayze, J. C. Andrews-Hanna, A.M. Baldridge, M. Chojnacki, J.L. Bishop, B.L. Ehlmann, S.L. Murchie, Roger N. Clark, F.P. Seelos, L.L. Tornabene, S. W. Squyres
Late Holocene slip rate of the San Andreas fault and its accommodation by creep and moderate-magnitude earthquakes at Parkfield, California Late Holocene slip rate of the San Andreas fault and its accommodation by creep and moderate-magnitude earthquakes at Parkfield, California
Investigation of a right-laterally offset channel at the Miller's Field paleoseismic site yields a late Holocene slip rate of 26.2 +6.4/−4.3 mm/yr (1σ) for the main trace of the San Andreas fault at Parkfield, California. This is the first well-documented geologic slip rate between the Carrizo and creeping sections of the San Andreas fault. This rate is lower than Holocene measurements...
Authors
N.A. Toke, J.R. Arrowsmith, Michael J. Rymer, A. Landgraf, D.E. Haddad, M. Busch, J. Coyan, A. Hannah
Developing empirical collapse fragility functions for global building types Developing empirical collapse fragility functions for global building types
Building collapse is the dominant cause of casualties during earthquakes. In order to better predict human fatalities, the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program requires collapse fragility functions for global building types. The collapse fragility is expressed as the probability of collapse at discrete levels of the input hazard...
Authors
K. Jaiswal, D. Wald, D. D’Ayala
Epistemic uncertainty in the location and magnitude of earthquakes in Italy from Macroseismic data Epistemic uncertainty in the location and magnitude of earthquakes in Italy from Macroseismic data
Three independent techniques (Bakun and Wentworth, 1997; Boxer from Gasperini et al., 1999; and Macroseismic Estimation of Earthquake Parameters [MEEP; see Data and Resources section, deliverable D3] from R.M.W. Musson and M.J. Jimenez) have been proposed for estimating an earthquake location and magnitude from intensity data alone. The locations and magnitudes obtained for a given set...
Authors
W. H. Bakun, Capera A. Gomez, M. Stucchi
The Mairan domes: silicic volcanic constructs on the Moon The Mairan domes: silicic volcanic constructs on the Moon
The Mairan domes are four features located in northern Oceanus Procellarum at ∼312.3E, 41.4N on the Moon. High resolution visible imagery, visible-to-mid-IR spectra, and Lunar Prospector Th abundance data all indicate that these four domes have a composition that is consistent with derivation from a Si-rich, highly evolved magma.
Authors
Timothy D. Glotch, Justin Hagerty, Paul G. Lucey, B. Ray Hawke, Thomas A. Giguere, Jessica A. Arnold, Jean-Pierre Williams, Bradley L. Jolliff, David A. Paige
Observations of changes in waveform character induced by the 1999 Mw7.6 Chi-Chi earthquake Observations of changes in waveform character induced by the 1999 Mw7.6 Chi-Chi earthquake
We observe changes in the waveforms of repeating earthquakes in eastern Taiwan following the 1999 Mw7.6 Chi-Chi earthquake, while their recurrence intervals appear to be unaffected. There is a clear reduction in waveform similarity and velocity changes indicated by delayed phases at the time of the Chi-Chi event. These changes are limited to stations in and paths that cross the 70 × 100...
Authors
K.H. Chen, T. Furumura, J. Rubinstein, R.-J. Rau
The ShakeOut scenario: A hypothetical Mw7.8 earthquake on the Southern San Andreas Fault The ShakeOut scenario: A hypothetical Mw7.8 earthquake on the Southern San Andreas Fault
In 2008, an earthquake-planning scenario document was released by the U.S. Geological Survey (USGS) and California Geological Survey that hypothesizes the occurrence and effects of a Mw7.8 earthquake on the southern San Andreas Fault. It was created by more than 300 scientists and engineers. Fault offsets reach 13 m and up to 8 m at lifeline crossings. Physics-based modeling was used to...
Authors
K. Porter, L. Jones, D. Cox, J. Goltz, K. Hudnut, D. Mileti, S. Perry, D. Ponti, M. Reichle, A.Z. Rose, C.R. Scawthorn, H.A. Seligson, K.I. Shoaf, J. Treiman, A. Wein
Economic resilience lessons from the ShakeOut earthquake scenario Economic resilience lessons from the ShakeOut earthquake scenario
Following a damaging earthquake, “business interruption” (BI)—reduced production of goods and services—begins and continues long after the ground shaking stops. Economic resilience reduces BI losses by making the best use of the resources available at a given point in time (static resilience) or by speeding recovery through repair and reconstruction (dynamic resilience), in contrast to...
Authors
A. Wein, A. Rose
The shakeout scenario: Meeting the needs for construction aggregates, asphalt, and concrete The shakeout scenario: Meeting the needs for construction aggregates, asphalt, and concrete
An Mw 7.8 earthquake as described in the ShakeOut Scenario would cause significant damage to buildings and infrastructure. Over 6 million tons of newly mined aggregate would be used for emergency repairs and for reconstruction in the five years following the event. This aggregate would be applied mostly in the form of concrete for buildings and bridges, asphalt or concrete for pavement...
Authors
W. H. Langer
A Miocene river in northern Arizona and its implications for the Colorado River and Grand Canyon A Miocene river in northern Arizona and its implications for the Colorado River and Grand Canyon
The southwesterly course of the pre–late Miocene Crooked Ridge River can be traced continuously for 48 km and discontinuously for 91 km in northern Arizona. It is visible today in inverted relief. Pebbles in the river gravel came from at least as far northeast as the San Juan Mountains. The river valley was carved out of easily eroded Jurassic and Cretaceous rocks, whose debris...
Authors
Ivo Lucchitta, Richard F. Holm, Baerbel K. Lucchitta