Publications
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Diatom influence on the production characteristics of hydrate-bearing sediments: Examples from Ulleung Basin, offshore South Korea
The Ulleung Basin Gas Hydrate field expeditions in 2007 (UBGH1) and 2010 (UBGH2) sought to assess the Basin's gas hydrate resource potential. Coring operations in both expeditions recovered evidence of gas hydrate, primarily as fracture-filling (or vein type) morphologies in mainly silt-sized, fine-grained sediment, but also as pore-occupying hydrate in the coarser-grained layers of interbedded sa
Authors
Junbong Jang, William F. Waite, Laura A. Stern, Joo Yong Lee
Flexible multimethod approach for seismic site characterization
We describe the flexible multimethod seismic site characterization technique for obtaining shear-wave velocity (VS) profiles and derivative information, such as the time-averaged VS of the upper 30 m (VS30). Simply stated, the multimethod approach relies on the application of multiple independent noninvasive site characterization acquisition and analysis techniques utilized in a flexible field-bas
Authors
William J. Stephenson, Alan Yong, Antony Martin
Beyond the teleseism: Introducing regional seismic and geodetic data into routine USGS finite‐fault modeling
The U.S. Geological Survey (USGS) National Earthquake Information Center (NEIC) routinely produces finite‐fault models following significant earthquakes. These models are spatiotemporal estimates of coseismic slip critical to constraining downstream response products such as ShakeMap ground motion estimates, Prompt Assessment of Global Earthquake for Response loss estimates, and ground failure ass
Authors
Dara Elyse Goldberg, Pablo Koch, Diego Melgar, Sebastian Riquelme, William L. Yeck
Documenting the multiple facets of a subsiding landscape from coastal cities and wetlands to the continental shelf
Land subsidence is a settling, sinking, or collapse of the land surface. In the southeastern United States, subsidence is frequently observed as sinkhole collapse in karst environments, wetland degradation and loss in coastal and other low-lying areas, and inundation of coastal urban communities. Human activities such as fluid extraction, mining, and overburden alteration can cause or exacerbate s
Authors
James G. Flocks, Eileen McGraw, John Barras, Julie Bernier, Mike Bradley, Devin L. Galloway, James Landmeyer, W. Scott McBride, Christopher Smith, Kathryn Smith, Christopher Swarzenski, Lauren Toth
By
Natural Hazards Mission Area, Water Resources Mission Area, Coastal and Marine Hazards and Resources Program, Caribbean-Florida Water Science Center (CFWSC), Lower Mississippi-Gulf Water Science Center, Ohio-Kentucky-Indiana Water Science Center, South Atlantic Water Science Center (SAWSC), St. Petersburg Coastal and Marine Science Center, Gulf of Mexico
Reproducibility and variability of earthquake subsidence estimates from saltmarshes of a Cascadia estuary
We examine fossil foraminiferal assemblages from 20 sediment cores to assess sudden relative sea-level (RSL) changes across three mud-over-peat contacts at three salt marshes in northern Humboldt Bay, California (~44.8°N, -124.2°W). We use a validated foraminiferal-based Bayesian transfer function to evaluate the variability of subsidence stratigraphy at a range of 30-6000 m across an estuary. We
Authors
Jason Scott Padgett, Simon E. Engelhart, Harvey M. Kelsey, Robert C. Witter, Niamh Cahill
Crowd-sourced SfM: Best practices for high resolution monitoring of coastal cliffs and bluffs
Structure from motion (SfM) photogrammetry is an increasingly common technique for measuring landscape change over time by deriving 3D point clouds and surface models from overlapping photographs. Traditional change detection approaches require photos that are geotagged with a differential GPS (DGPS) location, which requires expensive equipment that can limit the ability of communities and researc
Authors
Phillipe Alan Wernette, Ian M. Miller, Andrew C. Ritchie, Jonathan Warrick
Seismic monitoring solutions for buildings
This chapter introduces seismic monitoring of structural systems for buildings and begins with a historical background of this topic in the United States. After providing the historical context, the chapter reviews common seismic instrumentation issues such as utilization of data, code versus extensive instrumentation, free-field instrumentation, record synchronization requirements and more. Recen
Authors
Mehmet Çelebi, Yavuz Kaya
Real-time earthquake detection and alerting behavior of PLUM ground-motion-based early warning in the United States
We examine the real‐time earthquake detection and alerting behavior of the Propagation of Local Undamped Motion (PLUM) earthquake early warning (EEW) algorithm and compare PLUM’s performance with the real‐time performance of the current source‐characterization‐based ShakeAlert System. In the United States (U.S.), PLUM uses a two‐station approach to detect earthquakes. Once a detection is confirmed
Authors
Jessie Kate Saunders, Sarah E. Minson, Annemarie S. Baltay, Julian J Bunn, Elizabeth S. Cochran, Deborah L. Kilb, Colin T O'Rourke, Mitsuyuki Hoshiba, Yuki Kodera
Comparisons of the NGA-Subduction ground motion models
In this article, ground-motion models (GMMs) for subduction earthquakes recently developed as part of the Next Generation Attenuation-Subduction (NGA-Sub) project are compared. The four models presented in this comparison study are documented in their respective articles submitted along with this article. Each of these four models is based on the analysis of the large NGA-Sub database. Three of th
Authors
Nick Gregor, Kofi O. Addo, Norman A. Abrahamson, Linda Al Atik, Gail M. Atkinson, David Boore, Yousef Bozorgnia, Kenneth W. Campbell, Brian S.-J. Chiou, Zeynep Gulerce, Behzad Hassani, Tadahiro Kishida, Nicolas Kuehn, Silvia Mazzoni, Saburoh Midorikawa, Grace Alexandra Parker, Hongjun Si, Jonathan P. Stewart, Robert R. Youngs
The global seismographic network reveals atmospherically coupled normal modes excited by the 2022 Hunga Tonga eruption
The eruption of the submarine Hunga Tonga-Hunga Haʻapai (Hunga Tonga) volcano on 15 January 2022, was one of the largest volcanic explosions recorded by modern geophysical instrumentation. The eruption was notable for the broad range of atmospheric wave phenomena it generated and for their unusual coupling with the oceans and solid Earth. The event was recorded worldwide across the Global Seismogr
Authors
Adam T. Ringler, Robert E. Anthony, Rick Aster, T. Taira, Brian Shiro, David C. Wilson, S. H. De Angelis, C. Ebeling, Matthew M. Haney, R. Matoza, H. Ortiz
Crustal permeability changes observed from seismic attenuation: Impacts on multi-mainshock sequences
We use amplitude ratios from narrowband-filtered earthquake seismograms to measure variations of seismic attenuation over time, providing unique insights into the dynamic state of stress in the Earth’s crust at depth. Our dataset from earthquakes of the 2016-2017 Central Apennines sequence allows us to obtain high-resolution time histories of seismic attenuation (frequency band: 0.5-30 Hz) charact
Authors
Luca Malagnini, Thomas E. Parsons, Irene Munafo, Simone Mancini, Margarita Segou, Eric L. Geist
Graphite as an electrically conductive indicator of ancient crustal-scale fluid flow within mineral systems
Magnetotelluric (MT) imaging results from mineral provinces in Australia and in the United States show an apparent spatial relationship between crustal-scale electrical conductivity anomalies and major magmatic-hydrothermal iron oxide-apatite/iron oxide-copper-gold (IOA-IOCG) deposits. Although these observations have driven substantial interest in the use of MT data to image ancient fluid pathway
Authors
Benjamin Scott Murphy, Jan Marten Huizenga, Paul A. Bedrosian