Publications
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Emerging methods for the study of coastal ecosystem landscape structure and change
Coastal landscapes are heterogeneous, dynamic, and evolve over a range of time scales due to intertwined climatic, geologic, hydrologic, biologic, and meteorological processes, and are also heavily impacted by human development, commercial activities, and resource extraction. A diversity of complex coastal systems around the globe, spanning glaciated shorelines to tropical atolls, wetlands, and ba
Authors
John Brock, Jeffrey J. Danielson, Sam Purkis
A new dry hypothesis for the formation of Martian linear gullies
Long, narrow grooves found on the slopes of martian sand dunes have been cited as evidence of liquid water via the hypothesis that melt-water initiated debris flows eroded channels and deposited lateral levées. However, this theory has several short-comings for explaining the observed morphology and activity of these linear gullies. We present an alternative hypothesis that is consistent with the
Authors
Serina Diniega, Candice J. Hansen, Jim N. McElwaine, C.H. Hugenholtz, Colin M. Dundas, Alfred S. McEwen, Mary C. Bourke
Current research issues related to post-wildfire runoff and erosion processes
Research into post-wildfire effects began in the United States more than 70 years ago and only later extended to other parts of the world. Post-wildfire responses are typically transient, episodic, variable in space and time, dependent on thresholds, and involve multiple processes measured by different methods. These characteristics tend to hinder research progress, but the large empirical knowled
Authors
John A. Moody, Richard A. Shakesby, Peter R. Robichaud, Susan H. Cannon, Deborah A. Martin
Observations of the northern seasonal polar cap on Mars: I. Spring sublimation activity and processes
Spring sublimation of the seasonal CO2 northern polar cap is a dynamic process in the current Mars climate. Phenomena include dark fans of dune material propelled out onto the seasonal ice layer, polygonal cracks in the seasonal ice, sand flow down slipfaces, and outbreaks of gas and sand around the dune margins. These phenomena are concentrated on the north polar erg that encircles the northern r
Authors
C.J. Hansen, Shane Byrne, Ganna Portyankina, Mary C. Bourke, Colin M. Dovichin, Alfred S. McEwen, Michael T. Mellon, Antoine Pommerol, N. Thomas
Crater-based dating of geological units on Mars: methods and application for the new global geological map
The new, post-Viking generation of Mars orbital imaging and topographical data provide significant higher-resolution details of surface morphologies, which induced a new effort to photo-geologically map the surface of Mars at 1:20,000,000 scale. Although from unit superposition relations a relative stratigraphical framework can be compiled, it was the ambition of this mapping project to provide ab
Authors
Thomas Platz, Gregory Michael, Kenneth L. Tanaka, James A. Skinner, Corey M. Fortezzo
Publications of the Volcano Hazards Program 2011
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity, as funded by Congressional appropriation. Investigations are carried out by the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute, University of Hawaii Manoa and Hilo, University of Utah,
Authors
Manuel Nathenson
Introduction to the fifth Mars Polar Science special issue: key questions, needed observations, and recommended investigations
The Fifth International Conference on Mars Polar Science and Exploration – which was held from September 12–16, 2011, at the Pike’s Waterfront Lodge in Fairbanks, Alaska – is the latest in a continuing series of meetings that are intended to promote the exchange of knowledge and ideas between planetary and terrestrial scientists interested in Mars polar and climate research (http://www.lpi.usra.ed
Authors
Stephen M. Clifford, Kenji Yoshikawa, Shane Byrne, William Durham, David Fisher, Francois Forget, Michael Hecht, Peter Smith, Leslie Tamppari, Timothy Titus, Richard Zurek
Reappraisal of the relationship between the northern Nevada rift and Miocene extension in the northern Basin and Range Province
The northern Nevada rift is a prominent mafic dike swarm and magnetic anomaly in north-central Nevada inferred to record the Middle Miocene (16.5-15.0 Ma) extension direction in the northern Basin and Range province in the western United States. From the 245°-250° rift direction, Basin and Range extension is inferred to have shifted 45° clockwise to a modern direction of 290°-300° during the late
Authors
Joseph Colgan
Potentially induced earthquakes in Oklahoma, USA: links between wastewater injection and the 2011 Mw 5.7 earthquake sequence
Significant earthquakes are increasingly occurring within the continental interior of the United States, including five of moment magnitude (Mw) ≥ 5.0 in 2011 alone. Concurrently, the volume of fluid injected into the subsurface related to the production of unconventional resources continues to rise. Here we identify the largest earthquake potentially related to injection, an Mw 5.7 earthquake in
Authors
Katie M. Keranen, Heather M. Savage, Geoffrey A. Abers, Elizabeth S. Cochran
Correlating multispectral imaging and compositional data from the Mars Exploration Rovers and implications for Mars Science Laboratory
In an effort to infer compositional information about distant targets based on multispectral imaging data, we investigated methods of relating Mars Exploration Rover (MER) Pancam multispectral remote sensing observations to in situ alpha particle X-ray spectrometer (APXS)-derived elemental abundances and Mössbauer (MB)-derived abundances of Fe-bearing phases at the MER field sites in Gusev crater
Authors
Ryan B. Anderson, James F. Bell
Sea-level-induced seismicity and submarine landslide occurrence
The temporal coincidence between rapid late Pleistocene sea-level rise and large-scale slope failures is widely documented. Nevertheless, the physical mechanisms that link these phenomena are poorly understood, particularly along nonglaciated margins. Here we investigate the causal relationships between rapid sea-level rise, flexural stress loading, and increased seismicity rates along passive mar
Authors
Daniel S. Brothers, Karen M. Luttrell, Jason D. Chaytor
Geometry and earthquake potential of the shoreline fault, central California
The Shoreline fault is a vertical strike‐slip fault running along the coastline near San Luis Obispo, California. Much is unknown about the Shoreline fault, including its slip rate and the details of its geometry. Here, I study the geometry of the Shoreline fault at seismogenic depth, as well as the adjacent section of the offshore Hosgri fault, using seismicity relocations and earthquake focal me
Authors
Jeanne L. Hardebeck