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Publications

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Sediment export and impacts associated with river delta channelization compound estuary vulnerability to sea-level rise, Skagit River Delta, Washington, USA

Improved understanding of the budget and retention of sediment in river deltas is becoming increasingly important to mitigate and plan for impacts expected with sea level rise. In this study, analyses of historical bathymetric change, sediment core stratigraphy, and modeling are used to evaluate the sediment budget and environmental response of the largest river delta in the U.S. Pacific Northwest
Authors
Eric E. Grossman, Andrew W. Stevens, Peter Dartnell, Doug A George, David Finlayson

Forecasting for a fractured land: A case study of the communication and use of aftershock forecasts from the Mw 7.8 2016 Kaikōura earthquake in Aotearoa New Zealand

Operational earthquake forecasts (OEFs) are represented as time‐dependent probabilities of future earthquake hazard and risk. These probabilities can be presented in a variety of formats, including tables, maps, and text‐based scenarios. In countries such as Aotearoa New Zealand, the U.S., and Japan, OEFs have been released by scientific organizations to agencies and the public, with the intent of
Authors
Julia S. Becker, Sally H. Potter, Sara McBride, Emma E. Hudson-Doyle, Matthew Gerstenberger, Anne-Marie Christopherson

The effects of phosphatization on the mineral associations and speciation of Pb in ferromanganese crusts

The older layers of thick ferromanganese (FeMn) crusts from the central Pacific Ocean have undergone diagenetic phosphatization, during which carbonate fluorapatite (CFA) filled fractures and pore space and replaced carbonates. The effects of phosphatization on individual trace metal concentrations, speciation, and phase associations in FeMn crusts remain poorly understood yet may be important to
Authors
Kira Mizell, James R. Hein, Andrea Koschinsky, Sarah M. Hayes

Mars orbiter for resources, ices, and environments (MORIE)

The MORIE mission concept study examined the science and technical trade space to address high priority questions related to ice reservoirs and environmental transitions. The study team converged on a medium-class SEP-enabled orbiter with seven instruments to unlock the extent and volume of subsurface ice and geologic sequence stratigraphy through time. Observations would include the first radar i
Authors
Wendy M. Calvin, Nathaniel E. Putzig, John W Holt, Ali M Bramson, Colin M. Dundas, Bethany L. Ehlmann, Briony H. N. Horgan, Gareth A Morgan, Scott L. Murchie, G Wesley Patterson, Kimberly D. Seelos, Hanna G Sizemore, Steve Matousek, Ryan Woolley, Carlos Brinoccolo, Valerie Scott, Cassie Stuurman, Kevin Wheeler, Brian Sutin, Marc Lane, Nathan Barba, Ivair Gontijo, Katherine Park, Mariko Burgin, Scott Hensley, Jan Martin, Jean Biancone, David Hinkle, Barbara Insua

Exposure of an early to middle Noachian valley network in three dimensions on Mars

We document a set of channels in a section of the Martian cratered highlands located between crustal massifs northeast of Hellas Planitia that are visible in cross section and planview >200 m below the surface. The morphometry and spatial distribution of the outcrops provide concrete geological evidence of a dynamic aqueous system in a structural sub-basin during the Early to Middle Noachian, bols
Authors
James A. Skinner, Corey M. Fortezzo, Peter J. Mouginis-Mark

Compositional layering in Io driven by magmatic segregation and volcanism

The compositional evolution of volcanic bodies like Io is not well understood. Magmatic segregation and volcanic eruptions transport tidal heat from Io's interior to its surface. Several observed eruptions appear to be extremely high temperature (≥ 1600 K), suggesting either very high degrees of melting, refractory source regions, or intensive viscous heating on ascent. To address this ambiguity,
Authors
Dan C Spencer, Richard F. Katz, Ian J. Hewitt, David A. May, Laszlo P. Kestay

Developing post-alert messaging for ShakeAlert, the earthquake early warning system for the West Coast of the United States of America

As ShakeAlert, the earthquake early warning system for the West Coast of the U.S., begins its transition to operational public alerting, we explore how post-alert messaging might represent system performance. Planned post-alert messaging can provide timely, crucial information to both emergency managers and ShakeAlert operators as well as calibrate expectations among various publics or public user
Authors
Sara McBride, Ann Bostrom, Jeannette Sutton, Robert Michael deGroot, Annemarie S. Baltay, Brian Terbush, Paul Bodin, Maximilian Dixon, Emily Holland, Ryan Arba, Paul C. Laustsen, Sophia Liu, Margaret Vinci

Measuring basal force fluctuations of debris flows using seismic recordings and empirical green's functions

We present a novel method for measuring the fluctuating basal normal and shear stresses of debris flows by using along‐channel seismic recordings. Our method couples a simple parameterization of a debris flow as a seismic source with direct measurements of seismic path effects using empirical Green's functions generated with a force hammer. We test this method using two large‐scale (8 and 10 m3) e
Authors
Kate E. Allstadt, Maxime Farin, Richard M. Iverson, Maciej Obryk, Jason W. Kean, Victor C. Tsai, Thomas D Rapstine, Matthew Logan

Hydrothermal alteration on composite volcanoes: Mineralogy, hyperspectral imaging and aeromagnetic study of Mt Ruapehu, New Zealand

Prolonged volcanic activity can induce surface weathering and hydrothermal alteration that is a primary control on edifice instability, posing a complex hazard with its challenges to accurately forecast and mitigate. This study uses a frequently active composite volcano, Mt Ruapehu, New Zealand, to develop a conceptual model of surface weathering and hydrothermal alteration applicable to long‐live
Authors
Gabor Kereszturi, Lauren N. Schaefer, Craig A. Miller, Stuart Mead

Evaluating stereo DTM quality at Jezero Crater, Mars with HRSC, CTX, and HiRISE images

We have used a high-precision, high-resolution digital terrain model (DTM) of the NASA Mars 2020 rover Perseverance landing site in Jezero crater based on mosaicked images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (MRO HiRISE) camera as a reference dataset to evaluate DTMs based on Mars Express High Resolution Stereo Camera (MEX HRSC) and MRO Context camera (C
Authors
Randolph L. Kirk, Robin L. Fergason, Bonnie L. Redding, Donna M. Galuszka, Ethan Smith, David Mayer, Trent M. Hare, Klaus Gwinner

The recurrence interval of post-fire debris-flow generating rainfall in the southwestern United States

In the southwestern United States, post-fire debris flows commonly initiate during short bursts of intense rainfall. To date, the frequency of the rainfall rates has not been quantified. Here, we combine an existing database of debris-flow occurrences and corresponding peak storm intensities with a geospatial library of rainfall recurrence interval (RI) information and climate type to determine th
Authors
Dennis M. Staley, Jason W. Kean, Francis K. Rengers

Research is needed to inform environmental management of hydrothermally inactive and extinct polymetallic sulfide (PMS) deposits

Polymetallic sulfide (PMS) deposits produced at hydrothermal vents in the deep sea are of potential interest to miners. Hydrothermally active sulfide ecosystems are valued for the extraordinary chemosynthetic communities that they support. Many countries, including Canada, Portugal, and the United States, protect vent ecosystems in their Exclusive Economic Zones. When hydrothermal activity ceases
Authors
CL Van Dover, Ana Colaco, PC Collins, P Croot, Anna Metaxas, BJ Murton, A Swaddling, R Boschen-Rose, J Carlsson, L Cuyvers, Toshio Fukushima, Amy Gartman, R. Kennedy, C Kriete, NC Mestre, T Molodtsova, A Myhrvold, E Pelleter, SO Popoola, P-Y Qian, J Sarrazin, R Sharma, YJ Suh, JB Sylvan, Chunhui Tao, Michal Tomczak, J Vermilye