Physical Sciences and Mathematics Commons^™

Probing For Life In The Ocean Crust With The Lexen Program, H. Johnson, J. Baross, T. Bjorkland, W. Brazelton, J. Huber, M. Pruis, Susan Lang, F. Mccrosky, M. Mehta, D. Butterfield, A. Bowen, J. Howland, W. Martin, K. Roe, C. Channing, P. Kalk, C. Kammerer, R. Light, V. Miller, M. Mccarthy, B. Moore, M. Sharma, J. Voit

Susan Q. Lang

No abstract provided.

Crowdsourced Earthquake Early Warning, Sarah Minson, Benjamin Brooks, Craig Glennie, Jessica Murray, John Langbein, Susan Owen, Thomas Heaton, Robert Iannucci, Darren Hauser

Robert A Iannucci

Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

Estimating Unsaturated Hydraulic Functions For Coarse Sediment From A Field-Scale Infiltration Experiment, Michael Thoma, Warren Barrash, Michael Cardiff, John Bradford, Jodi Mead

Jodi Mead

A field-scale infiltration experiment was conducted in coarse conglomeratic soil with high gravel fraction. Unsaturated flow properties were estimated from modeling of infiltration using the van Genuchten–Mualem model and a Metropolis–Hasting optimization scheme. Results provide optimal unsaturated flow parameters for a soil type that is underrepresented for vadose zone flow. Conglomeratic alluvial sediments (sand–gravel–cobbles) are common in fluvial, periglacial, and tectonically active regions but have received little attention with respect to unsaturated flow, specifically moisture–tension–conductivity relationships, due to difficulty in making measurements in the field or laboratory and lack of agricultural value. We used a field-scale infiltration experiment, a one-dimensional …

South Australian Historical Earthquakes In The Pre-Instrumental Period 1837-1963: A Comprehensive Chronicle And Analysis Of Available Intensity Data, Katherine Dix

Dr Katherine Dix

Nearest Neighbor Methods Applied To Dune Field Organization: The Coral Pink Sand Dunes, Kane County, Utah, Usa, David Wilkins, Richard Ford

David E. Wilkins

Dune fields have recently come to be recognized as self-organizing systems that can be seen progressing from states of disorganization or randomness to uniformity. Dune systems can be highly sensitive to changes in factors, such as climate and sediment transport, that determine system state. Changes in climate and sediment state can take time to work their way through a dune system; this, in turn, leads to spatial heterogeneity in dune field organization. Using the Coral Pink Sand Dunes in southern Utah as a model, this study tests nearest neighbor analysis adapted as a method to objectively identify and characterize differences …

Palaeolake Shoreline Sequencing Using Ground Penetrating Radar: Lake Alvord, Oregon, And Nevada, David Wilkins, William Clement

David E. Wilkins

Field, map, and aerial photoreconnaissance in the Lake Alvord basin has focused on identifying late Pleistocene depositional shoreline features (e.g., tombolos, spits, barriers). Features in different areas of the basin are well defined, and their spatial extents are easily mapped; however, absolute---or even relative-ages of shoreline features are not clear. Ground penetrating radar (GPR) was used to distinguish between intermediate and highstand stage shorelines during what is thought to have been the latest Pleistocene, threshold-controlled lake cycle. Radar transects of 280 and 600 m imaged a spit and a baymouth barrier at sites in the northeastern quadrant of the basin …

Constraining The Exhumation And Burial History Of The Safod Pilot Hole With Apatite Fission Track And (U-Th)/He Thermochronometry, Ann Blythe, M D’Alessio, R Bürgmann

Ann Blythe

[1] The San Andreas Fault Observatory at Depth (SAFOD) pilot hole traverses the upper 2 km of a site 1.8 km west of the San Andreas fault (SAF) near Parkfield, California. In order to evaluate the burial and exhumation history of the site and its relationship to the kinematics and mechanics of the SAF, we use 15 apatite fission-track (FT) and 5 (U-Th)/He analyses from pilot hole samples to document their thermal history. Sample ages decrease with depth: FT and (U-Th)/He ages range from ∼60 and ∼31 Ma, respectively, in the upper 800 m of the hole to ∼3 and …