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Amazon sediment transport and accumulation along the continuum of mixed fluvial and marine processes

Sediment transfer from land to ocean begins in coastal settings and, for large rivers such as the Amazon, has dramatic impacts over thousands of kilometers covering diverse environmental conditions. In the relatively natural Amazon tidal river, combinations of fluvial and marine processes transition toward the ocean, affecting the transport and accumulation of sediment in floodplains and tributary
Authors
Charles A. Nittrouer, David J. DeMaster, Steven A. Kuehl, Alberto G. Figueiredo, Richard W. Sternberg, L. Ercilio C. Faria, Odete M. Silveira, Meade A. Allison, Gail C. Kineke, Andrea S. Ogston, Pedro W.M. Souza Filho, Nils E. Asp, Daniel J. Nowacki, Aaron T. Fricke

Global quieting of high-frequency seismic noise due to COVID-19 pandemic lockdown measures

Human activity causes vibrations that propagate into the ground as high-frequency seismic waves. Measures to mitigate the COVID-19 pandemic caused widespread changes in human activity, leading to a months-long reduction in seismic noise of up to 50%. The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic noise reduction on record. While the reduction is
Authors
Thomas Lecocq, Stephen Hicks, Koen Van Noten, Kasper van Wijk, Paula Koelemeijer, Raphael S.M. De Plaen, Frederick Massin, Gregor Hillers, Robert E. Anthony, Maria-Theresia Apoloner, Mario Arroyo-Solorzano, Jelle D. Assink, Pinar Buyukakpinar, Andrea Cannata, Flavio Cannavo, Sebastian Carrasco, Corentin Caudron, Esteban J. Chaves, David G. Cornwell, David Craig, Oliver F.C. den Ouden, Jordi Diaz, Stefanie Donner, Christos P. Evangelidis, Laslo Evers, Benoit Fauville, Gonzalo A. Fernandez, Dimitrios Giannopoulos, Steven J. Gibbons, Társilo Girona, Bogdan Grecu, Marc Grunberg, Gyorgy Hetenyi, Anna Horleston, Adolfo Inza, Jessica C.E. Irving, Mohammadreza Jamalreyhani, Alan Kafka, Mathijs R. Koymans, Celeste Labedz, Eric Larose, Nathaniel J. Lindsey, Mika McKinnon, Tobias Megies, Meghan S. Miller, William G. Minarik, Louis Moresi, Victor H. Marquez-Ramirez, Martin Mollhoff, Ian Nesbitt, Shankho Niyogi, Javier Ojeda, Adrien Oth, Simon Proud, Jay Pulli, Lise Retailleau, Annukka E. Rintamaki, Claudio Satriano, Martha K. Savage, Shanhar Shani-Kamiel, Reinoud Sleeman, Efthimios Sokos, Klaus Stammler, Alexander E. Stott, Shiba Subedi, Mathilde B. Sorensen, Taka'aki Taira, Mar Tapia, Faith Turhan, Ben van der Pluijm, Mark Vanstone, Jerome Vernge, Tommi A.T. Vuorinen, Tristram Warren, Joachim Wassermann, Han Xiao

Reconstructing the velocity and deformation of a rapid landslide using multiview video

Noncontact measurements of spatially varied ground surface deformation during landslide motion can provide important constraints on landslide mechanics. Here, we present and test a new method for extracting measurements of rapid landslide surface displacement and velocity (accelerations of approximately 1 m/s2) using sequences of stereo images obtained from a pair of inexpensive, stationary 4K vid
Authors
Thomas D Rapstine, Francis K. Rengers, Kate E. Allstadt, Richard M. Iverson, Joel B. Smith, Maciej Obryk, M. Logan, M. J. Olsen

The importance of explicitly modelling sea-swell waves for runup on reef-lined coasts

The importance of explicitly modelling sea-swell waves for runup was examined using a 2D XBeach short wave-averaged (surfbeat, “XB-SB”) and a wave-resolving (non-hydrostatic, “XB-NH”) model of Roi-Namur Island on Kwajalein Atoll in the Republic of Marshall Islands. Field observations on water levels, wave heights, and wave runup were used to drive and evaluate both models, which were subsequently
Authors
Ellen Quataert, Curt D. Storlazzi, Ap van Dongeren, Robert T. McCall

Bellwether sites for evaluating changes in landslide frequency and magnitude in cryospheric mountainous terrain: A call for systematic, long-term observations to decipher the impact of climate change

Permafrost and glaciers are being degraded by the warming effects of climate change. The impact that this degradation has on slope stability in mountainous terrain is the subject of ongoing research efforts. The relatively new availability of high-resolution (≤ 10 m) imagery with worldwide coverage and short (≤ 30 days) repeat acquisition times, as well as the emerging field of environmental seism
Authors
Jeffrey A. Coe

The chemostratigraphy of the Murray formation and role of diagenesis at Vera Rubin ridge in Gale crater, Mars, as observed by the ChemCam instrument

Geochemical results are presented from Curiosity’s exploration of the Vera Rubin ridge (VRR), in addition to the full chemostratigraphy of the predominantly lacustrine mudstone Murray formation up to and including VRR. VRR is a prominent ridge flanking Aeolis Mons (informally Mt. Sharp), the central mound in Gale crater, Mars, and was a key area of interest for the Mars Science Laboratory mission.
Authors
Jens Frydenvang, Nicholas Mangold, Roger C. Wiens, Abigail A. Fraeman, Lauren A. Edgar, Christopher M. Fedo, Jonas L'Haridon, Candice C. Bedford, Sanjeev Gupta, John P. Grotzinger, Jon C. Bridges, Ben C. Clark, Elizabeth B. Rampe, Olivier Gasnaut, Sylvestre Maurice, Patrick J. Gasda, Nina L. Lanza, Ann M. Olilla, Pierre-Yves Meslin, Valerie Payre, Fred J. Calef, Mark R Salvatore, Christopher H House

Pseudo-prospective evaluation of UCERF3-ETAS forecasts during the 2019 Ridgecrest sequence

The 2019 Ridgecrest sequence provides the first opportunity to evaluate Uniform California Earthquake Rupture Forecast v.3 with epidemic‐type aftershock sequences (UCERF3‐ETAS) in a pseudoprospective sense. For comparison, we include a version of the model without explicit faults more closely mimicking traditional ETAS models (UCERF3‐NoFaults). We evaluate the forecasts with new metrics developed
Authors
William J. Savran, Maximillian J. Werner, W. Marzocchi, David A. Rhoades, David D. Jackson, Kevin R. Milner, Edward H. Field, Andrew J. Michael

U.S. Geological Survey STATEMAP Program—Geologic mapping for the public good

As of 2020, STATEMAP has invested more than $150 million in 48 State geological surveys, matched dollar for dollar, to complete geologic mapping projects crucial to the health and security of State natural resources and residents. For more information about STATEMAP and other geologic mapping efforts supported by the National Cooperative Geologic Mapping Program, visit https://ncgmp.usgs.gov.
Authors
Abby Ackerman, Darcy McPhee

Evidence of previous faulting along the 2019 Ridgecrest, California earthquake ruptures

The July 2019 Ridgecrest earthquake sequence in southeastern California was characterized as surprising because only ~35% of the rupture occurred on previously mapped faults. Employing more detailed inspection of pre-event high-resolution topography and imagery in combination with field observations, we document evidence of active faulting in the landscape along the entire fault system. Scarps, de
Authors
Jessica Thompson Jobe, Belle E. Philibosian, Colin Chupik, Timothy E. Dawson, Scott E. K. Bennett, Ryan D. Gold, Christopher DuRoss, Tyler C. Ladinsky, Katherine J. Kendrick, Elizabeth Haddon, Ian Pierce, Brian J. Swanson, Gordon G. Seitz

Factors influencing the probability of hydraulic fracturing induced seismicity in Oklahoma

Injection‐induced seismicity became an important issue over the past decade, and although much of the rise in seismicity is attributed to wastewater disposal, a growing number of cases have identified hydraulic fracturing (HF) as the cause. A recent study identified regions in Oklahoma where ≥75% of seismicity from 2010 to 2016 correlated with nearly 300 HF wells. To identify factors associated wi
Authors
Rosamiel Ries, Michael R. Brudzinski, Robert Skoumal, Brian S. Currie

On the use of receiver operating character tests for evaluating spatial earthquake forecasts

Spatial forecasts of triggered earthquake distributions have been ranked using receiver operating characteristic (ROC) tests. The test is a binary comparison between regions of positive and negative forecast against positive and negative presence of earthquakes. Forecasts predicting only positive changes score higher than Coulomb methods, which predict positive and negative changes. I hypothesize
Authors
Thomas E. Parsons

ShakeAlert Earthquake Early Warning System Performance During the 2019 Ridgecrest Earthquake Sequence

During July 2019, a sequence of earthquakes including a Mw6.4 foreshock and a Mw7.1 mainshock occurred near Ridgecrest, California. ShakeAlert, the U.S. Geological Survey (USGS) ShakeAlert public Earthquake Early Warning (EEW) system being developed for the U.S. West Coast, was operational during this time, though public alerting was only available within LA County. ShakeAlert created alert messag
Authors
Angela Chung, Men-Andrin Meier, Jennifer Andrews, Maren Böse, Brendan Crowell, Jeffrey McGuire, Deborah Smith