Publications
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Collision structures of the Prince William terrane and Chugach terrane docking along the Shumagin and Unimak convergent margins, Alaska, USA
Western Alaska’s convergent margins are composed of tectonostratigraphic terranes. On land, terrane assembly is recognized along boundaries or sutures between neighboring geologic elements with distinctly different origins. In marine areas where rock outcrops are covered by sediment, recognizing terrane sutures is problematic. A fault in seismic dip line 5 of the ALEUT project has been interpreted
Authors
Roland E. von Huene, John J. Miller
Global variability of the composition and temperature at the 410-km discontinuity from receiver function analysis of dense arrays
Seismic boundaries caused by phase transitions between olivine polymorphs in Earth's mantle provide thermal and compositional markers that inform mantle dynamics. Seismic studies of the mantle transition zone often use either global averaging with sparse arrays or regional sampling from a single dense array. The intermediate approach of this study utilizes many densely spaced seismic arrays distri
Authors
Margaret Elizabeth Glasgow, Hankui K. Zhang, Brandon Schmandt, Wen-Yi Zhou, Jinchi Zhang
Debris avalanches in the northern California Coast Range triggered by plate boundary earthquakes
Determining the timing and cause for ancient hillslope failures proves difficult in the western United States, yet critical as it ties directly into groundmotion estimates for hazardous events. This knowledge gap is important to confront as hillslope failures are candidates to be triggered by earthquakes along active plate boundaries. We identify two prehistoric, i.e., preinstrumental history, deb
Authors
Jessie K. Pearl, Harvey Kelsey, Stephen J. Angster, Dylan Caldwell, Ian Pryor, Brian Sherrod
Wildfire, extreme precipitation and debris flows, oh my! Channel response to compounding disturbances in a mountain stream in the Upper Colorado Basin, USA
Compounding changes in climate and human activities stand to increase sediment input to rivers in many landscapes, including via discrete perturbations such as post-fire debris flows. Because sediment supply is a dominant control on river morphology, understanding mountain river responses to sediment regime perturbations is critical to predicting and addressing downstream effects to infrastructure
Authors
Paxton Ridgeway, Belize Lane, Haley Canham, Brendan Murphy, Patrick Belmont, Francis K. Rengers
A comparison of CO2 seasonal activity in Mars' northern and southern hemispheres
Carbon dioxide is Mars' most active volatile. The seasonal and diurnal processes of when and where it condenses and sublimates are determined by energy balance between the atmosphere and surface ice in Mars' vapor pressure equilibrium climate. Mars' current obliquity ensures that the polar caps are stable locations for seasonal condensation. The eccentricity of Mars' orbit is the major driver of d
Authors
Candice J. Hansen, Shane Byrne, Wendy M. Calvin, Serina Diniega, Colin M. Dundas, Paul O. Hayne, Alfred S. McEwen, Lauren E McKeown, Sylvain Piqueux, Ganna Portyankina, Meg E Schwamb, Timothy N. Titus, Jacob M Widmer
The High-Resolution Imaging Science Experiment (HiRISE) in the MRO extended science phases (2009–2023)
The Mars Reconnaissance Orbiter has been orbiting Mars since 2006 and has acquired >80,000 HiRISE images with sub-meter resolution, contributing to over 2000 peer-reviewed publications, and has provided the data needed to enable safe surface landings in key locations by several rovers or landers. This paper describes the changes to science planning, data processing, and analysis tools since the in
Authors
Alfred S. McEwen, Shane Byrne, Candice J. Hansen, Ingrid J. Daubar, Sarah Sutton, Colin M. Dundas, Nicole Bardabelias, Nicole Baugh, James W. Bergstrom, Ross A. Beyer, Kristin M Block, Veronica Bray, John C. Bridges, Matthew Chojnacki, Susan J. Conway, W Alan Delamere, T. Ebben, Yisrael Espinosa, Audrie Fennema, John Grant, Virginia C Gulick, Kenneth E. Herkenhoff, Rodney Heyd, Richard Leis, Lujendra Ojha, Singleton Papendick, Christian Schaller, Nicolas Thomas, Livio L. Tornabene, Catherine M. Weitz, Sharon A. Wilson
Polar science results from Mars Reconnaissance Orbiter: Multiwavelength, multiyear insights
Mars Reconnaissance Orbiter (MRO), with its arrival in 2006 and nearly continuous operation since, has provided data for the study of martian polar processes spanning nine Mars years. Mars' polar deposits have long been thought to preserve records of past climates, potentially readable like terrestrial ice cores. However, unraveling millions of years of history in the ice depends on understanding
Authors
Margaret E. Landis, P. J. Acharya, N. R. Alsaeed, C. Andres, Patricio Becerra, Wendy M. Calvin, E. M. Cangi, S. F. A. Cartwright, M. S. Chaffin, Serina Diniega, Colin M. Dundas, Candice J. Hansen, Paul O. Hayne, Kenneth E. Herkenhoff, David M. Kass, Aditya R. Khuller, Lauren McKeown, Patrich S. Russell, Isaac B. Smith, Sarah S. Sutton, J. M. Widmer, Jennifer L Whitten
New, dated small impacts on the South Polar Layered Deposits (SPLD), Mars, and implications for shallow subsurface properties
The Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) imaged two newly formed impact craters on the South Polar Layered Deposits (SPLD) of Mars in 2018 and 2020. These two new craters, the first detected on the SPLD, measure ∼17 m and ∼48 m in diameter. Follow-up observations were conducted with the High Resolution Imaging Science Experiment (HiRISE), showing seasonal and interannual changes,
Authors
Margaret E. Landis, Colin M. Dundas, Alfred S. McEwen, Ingrid J. Daubar, Paul O. Hayne, Shane Byrne, Sarah S. Sutton, Vidhya Ganesh Rangarajan, Livio L. Tornabene, Andrew Britton, Kenneth E. Herkenhoff
Novel quantitative methods to enable multispectral identification of high-purity water ice exposures on Mars using High Resolution Imaging Science Experiment (HiRISE) images
Reliable detection and characterization of water ice on the Martian surface is pivotal to not only understand its present and past climate, but to also provide valuable information on in-situ resource availability and distribution for future human exploration missions. Ice-rich features are currently identified with visible/near-IR (VNIR), thermal IR and radar data. However, their coarse spatial s
Authors
Vidhya Ganesh Rangarajan, Livio L. Tornabene, G. R. Osinski, Colin M. Dundas, Ross A. Beyer, Kenneth E. Herkenhoff, Shane Byrne, Rodney Heyd, Frank P. Seelos, G. Munaretto, Angela Dapremont
Probabilistic assessment of postfire debris-flow inundation in response to forecast rainfall
Communities downstream of burned steep lands face increases in debris-flow hazards due to fire effects on soil and vegetation. Rapid postfire hazard assessments have traditionally focused on quantifying spatial variations in debris-flow likelihood and volume in response to design rainstorms. However, a methodology that provides estimates of debris-flow inundation downstream of burned areas based o
Authors
A. B. Prescott, L. A. McGuire, K.-S. Jun, Katherine R. Barnhart, N. S. Oakley
Geological context and significance of the clay-sulfate transition region in Mount Sharp, Gale crater, Mars: An integrated assessment based on orbiter and rover data
On Mars, phyllosilicate (“clay”) minerals are often associated with older terrains, and sulfate minerals are associated with younger terrains, and this dichotomy is taken as evidence that Mars’ surface dried up over time. Therefore, in situ investigation of the Mount Sharp strata in Gale crater, which record a shift from dominantly clay-bearing to sulfate-bearing minerals, as seen in visible−near-
Authors
Melissa J. Meyer, Ralph E. Milliken, Kathryn M. Stack, Lauren A. Edgar, Elizabeth B. Rampe, Madison L. Turner, Kevin W. Lewis, Edwin S. Kite, Gwenael Caravaca, Ashwin R. Vasavada, William E. Dietrich, Alex B. Bryk, Olivier Gasnault, Stephane Le Mouelic, Christina H. Seeger, Rachel Y. Sheppard
Relatively stable pressure effects and time-increasing thermal contraction control Heber geothermal field deformation
Due to geological complexities and observational gaps, it is challenging to identify the governing physical processes of geothermal field deformation including ground subsidence and earthquakes. In the west and east regions of the Heber Geothermal Field (HGF), decade-long subsidence was occurring despite injection of heat-depleted brines, along with transient reversals between uplift and subsidenc
Authors
Guoyan Jiang, Andrew Barbour, Robert John Skoumal, Kathryn Zerbe Materna, Aren Crandall-Bear