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Publications

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Microseismic events associated with the Oroville Dam spillway

On 14 February 2017, two small (equivalent MD 0.8 and 1.0) seismic events occurred in proximity to the Oroville Dam in the Sierra Nevada foothills, California. To examine possible causal relationships between these events and reservoir operations, including the spillway failure starting prior to these events, we applied a new optimized template matching approach to seismic data between May 1993 -
Authors
Robert J. Skoumal, Phillip B. Dawson, Stephen H. Hickman, J. Ole Kaven

Ground motions from induced earthquakes in Oklahoma and Kansas

Improved predictions of earthquake ground motions are critical to advancing seismic hazard analyses and earthquake response. The high seismicity rate from 2009 to 2016 in Oklahoma and Kansas provides an extensive data set for examining the ground motions from these events. We evaluate the ability of three suites of ground‐motion prediction equations (GMPEs)—appropriate for modeling tectonic earthq
Authors
Morgan P. Moschetti, Eric M. Thompson, Peter M. Powers, Susan M. Hoover, Daniel E. McNamara

Salt marsh ecosystem restructuring enhances elevation resilience and carbon storage during accelerating relative sea-level rise

Salt marshes respond to sea-level rise through a series of complex and dynamic bio-physical feedbacks. In this study, we found that sea-level rise triggered salt marsh habitat restructuring, with the associated vegetation changes enhancing salt marsh elevation resilience. A continuous record of marsh elevation relative to sea level that includes reconstruction of high-resolution, sub-decadal, mars
Authors
Meagan Gonneea Eagle, Christopher V. Maio, Kevin D. Kroeger, Andrea D. Hawkes, Jordan Mora, Richard Sullivan, Stephanie Madsen, Richard M. Buzard, Niamh Cahill, Jeffrey P. Donnelly

On the contribution of waves to total coastal water level changes in the context of sea level rise: a response to Melet, et al. (2018)

Response to Melet, A., Meyssignac, B., Almar, R. & Le Cozannet, G. Under-estimated wave contribution to coastal sea-level rise. Nat. Clim. Change 8, 234–239 (2018). In a recent paper, Melet et al.1 claim that the contribution of wind-waves to coastal sea-level rise has been under-estimated. Although we agree with the overall premise that coastal wind-wave dynamics are important when assessing the
Authors
Jerome Aucan, Ron Hoeke, Curt D. Storlazzi, Justin Stopa, Moritz Wandres, Ryan J. Lowe

Hydrologic controls of methane dynamics in karst subterranean estuaries

Karst subterranean estuaries (KSEs) extend into carbonate platforms along 12% of all coastlines. A recent study has shown that microbial methane (CH4) consumption is an important component of the carbon cycle and food web dynamics within flooded caves that permeate KSEs. In this study, we obtained high‐resolution (~2.5‐day) temporal records of dissolved methane concentrations and its stable isotop
Authors
David Brankovits, John W. Pohlman, Neil K. Ganju, T.M. Iliffe, N. Lowell, E. Roth, S.P. Sylva, J.A. Emmert, L. L. Lapham

Seismology with dark data: Image-based processing of analog records using machine learning for the rangely earthquake control experiment

Before the digital era, seismograms were recorded in analog form and read manually by analysts. The digital era represents only about 25% of the total time span of instrumental seismology. Analog data provide important constraints on earthquake processes over the long term, and in some cases are the only data available. The media on which analog data are recorded degrades with time and there is an
Authors
Kaiwen Wang, William L. Ellsworth, Gregory C. Beroza, Gordon Williams, Miao Zhang, Dustin Schroeder, Justin L. Rubinstein

A 50-year Sr/Ca time series from an enclosed, shallow-water Guam coral: In situ monitoring and extraction of a temperature trend, annual cycle, and ENSO and PDO signals

Located on the northern edge of the West Pacific Warm Pool and having a developed economy and modern infrastructure, Guam is well positioned and equipped for obtaining natural records of the west Pacific maritime paleoclimate. This study was a proof of concept to explore whether useful climate proxy records might be obtained from coral at readily accessible, even if geochemically nonoptimal, coast
Authors
Tomoko Bell, Mark Lander, John Jenson, Richard Randall, Judson W. Partin, Nancy G. Prouty

On the intensity of the magnetic superstorm of September 1909

Analysis is made of solar observations and ground‐based magnetometer data recording space weather before and during the magnetic superstorm of 25 September 1909. From these data, it is inferred that the storm was initiated by an interplanetary coronal‐mass ejection having a mean Sun‐to‐Earth velocity of ~1,679 km/s. The commencement pressure on the magnetopause was ~32.4 nPa, sufficient to compres
Authors
Jeffrey J. Love, Hisashi Hayakawa, Edward W. Cliver

Updated California aftershock parameters

Reasenberg and Jones (1989) introduced a statistical model for aftershock rate following a mainshock along with estimates of “generic” California parameter values based on past aftershock sequences. The Reasenberg and Jones (1989) model has been used for decades to issue aftershock forecasts following M≥5 mainshocks in California. Here, we update the “generic” parameters for California through a f
Authors
Jeanne L. Hardebeck, Andrea L. Llenos, Andrew J. Michael, Morgan T. Page, Nicholas van der Elst

The Albuquerque Seismological Lab WWSSN film chip preservation project

From 1961 to 1996, the Albuquerque Seismological Laboratory (ASL) installed and operated the World‐Wide Standardized Seismograph Network (WWSSN). Each station within the network consisted of three Benioff short‐period sensors and three Sprengnether Press‐Ewing long‐period sensors along with recording, timing, and calibration equipment. Approximately 3.7 million single‐day record film chips were cr
Authors
Alexis Casondra Bianca Alejandro, Charles R. Hutt, Adam T. Ringler, Sabrina Veronica Moore, Robert E. Anthony, David C. Wilson

Global Earthquake Model (GEM) Risk Map

The Global Earthquake Risk Map (v2018.1) comprises four global maps. The main map presents the geographic distribution of average annual loss (USD) normalized by the average construction costs of the respective country (USD/m2 due to ground shaking in the residential, commercial and industrial building stock, considering contents, structural and non-structural components. The normalized metri
Authors
V. Silva, D. Amo-Oduro, A. Calderon, J. Dabbeek, V. Despotaki, L. Martins, A. Rao, M. Simionato, D. Vigano, C. Yepes, A. Acevedo, H. Crowley, Nick Horspool, Kishor S. Jaiswal, M. Journeay, M. Pittore

Geomorphic evolution of a gravel‐bed river under sediment‐starved vs. sediment‐rich conditions: River response to the world's largest dam removal

Understanding river response to sediment pulses is a fundamental problem in geomorphic process studies, with myriad implications for river management. However, because large sediment pulses are rare and usually unanticipated, they are seldom studied at field scale. We examine fluvial response to a massive (~20 Mt) sediment pulse released by the largest dam removal globally, on the Elwha River, Was

Authors
Amy E. East, Joshua B. Logan, Mark C. Mastin, Andrew C. Ritchie, Jennifer A. Bountry, Christopher S. Magirl, Joel B. Sankey