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Aftershock forecasting

Aftershocks can compound the impacts of a major earthquake, disrupting recovery efforts and potentially further damaging weakened buildings and infrastructure. Forecasts of the probability of aftershocks can therefore aid decision-making during earthquake response and recovery. Several countries issue authoritative aftershock forecasts. Most aftershock forecasts are based on simple statistical
Authors
Jeanne L. Hardebeck, Andrea L. Llenos, Andrew J. Michael, Morgan T. Page, Max Schneider, Nicholas van der Elst

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

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

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

Uncertainty in ground-motion-to-intensity conversions significantly affects earthquake early warning alert regions

We examine how the choice of ground‐motion‐to‐intensity conversion equations (GMICEs) in earthquake early warning (EEW) systems affects resulting alert regions. We find that existing GMICEs can underestimate observed shaking at short rupture distances or overestimate the extent of low‐intensity shaking. Updated GMICEs that remove these biases would improve the accuracy of alert regions for the Sha
Authors
Jessie Saunders, Annemarie S. Baltay, Sarah E. Minson, Maren Böse

Fire effects on geomorphic processes

Fire-induced geomorphic changes, such as enhanced erosion and debris-flow activity, are expected to increase with climate change owing to increases in fire activity and rainfall intensification. In this Review, we summarize how landscape attributes, rainfall and burn severity influence post-fire geomorphic responses over a range of temporal and spatial scales. Sub-hourly rainfall intensity and bur
Authors
Luke McGuire, Brian A. Ebel, Francis K. Rengers, Diana Vieira, Petter Nyman