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Publications

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A numerical study of wave-driven mean flows and setup dynamics at a coral reef-lagoon system

Two-dimensional mean wave-driven flow and setup dynamics were investigated at a reef-lagoon system at Ningaloo Reef, Western Australia, using the numerical wave-flow model, SWASH. Phase-resolved numerical simulations of the wave and flow fields, validated with highly detailed field observations (including >10 sensors through the energetic surf zone), were used to quantify the main mechanisms that
Authors
Dirk P. Rijnsdorp, Mark L. Buckley, Renan da Silva, Mike Cuttler, Jeff Hansen, Ryan Lowe, Rebecca H. Green, Curt Storlazzi

Temporal seismic velocity variations: Recovery following from the 2019 Mw 7.1 Ridgecrest, California earthquake

We investigated seismic velocity changes (dv/v) associated with the 2019 Ridgecrest earthquake sequence with high‐frequency autocorrelations of ambient seismic noise data. Daily autocorrelation functions were computed for the entirety of 2019 and the first quarter of 2020 for broadband stations within the region, including the temporary broadband stations installed during the aftershock deployment
Authors
Joshua Dakota Boschelli, Morgan P. Moschetti, C Sens-Schonfelder

A probabilistic framework to model distributions of VS30

The time‐averaged shear‐wave velocity in the upper 30 m depth from the ground surface, or VS30⁠, is often used as a predictor to describe local site effects in ground‐motion models. Although VS30 is typically determined from in situ measurements, it is not always feasible to obtain such measurements due to project restrictions or site accessibility. This motivates the development and use of proxy‐
Authors
Utkarsh Mital, Sean K Ahdi, Julie A Herrick, Junko Iwahashi, Alexandros Savvaidis, Alan Yong

Rapid strain release on the Bear River fault zone, Utah–Wyoming—The impact of preexisting structure on the rupture behavior of a new normal fault

Earthquake clustering (grouping in space and time) is a widely observed mode of strain release in the upper crust, although this behavior on individual faults is a departure from classic elastic rebound theory. In this study, we consider factors responsible for a cluster of earthquakes on the Bear River fault zone (BRF), a recently activated, 44-km-long normal fault on the eastern margin of Basin
Authors
Suzanne Hecker, David P. Schwartz, Stephen B. DeLong

Electrical conductivity of pure CO2 hydrate and CH4 hydrate: Role of the guest molecule

To conclude a series of DOE-sponsored laboratory experiments in which our team measured electrical conductivity of methane hydrate-bearing samples, we investigated electrical conductivity of CO2 hydrate for direct comparison with methane hydrate. Their surprisingly distinct signatures could aid in the monitoring of CO2 in certain deep marine environments. To the best of our knowledge these are the
Authors
Laura A. Stern, S. Constable, Ryan Lu, Wyatt L. Du Frane, J. Murray Roberts

Potential use of the benthic foraminifers Bulimina denudata and Eggerelloides advenus in marine sediment toxicity testing

The benthic foraminifers Bulimina denudata and Eggerelloides advenus are commonly abundant in offshore regions in the Pacific Ocean, especially in waste-discharge sites. The relationship between their abundance and standard macrofaunal sediment toxicity tests (amphipod survival and sea urchin fertilization) as well as sediment chemistry analyte measurements were determined for sediments collected
Authors
Mary McGann

Extreme-event magnetic storm probabilities derived from rank statistics of historical Dst intensities for solar cycles 14-24

A compilation is made of the largest and second-largest magnetic-storm-maximum intensities, −Dst1 and −Dst2, for solar cycles 14–24 (1902–2016) by sampling Oulu Dcx for cycles 19–24, using published −Dstm values for 4 intense storms in cycles 14, 15, and 18 (1903, 1909, 1921, 1946), and calculating 15 new storm-maximum −Dstm values (reported here) for cycles 14–18. Three different models are fitte
Authors
Jeffrey J. Love

Numerical analysis of the effect of subgrid variability in a physically based hydrological model on runoff, soil moisture, and slope stability

In coarse resolution hydrological modeling we face the problem of subgrid variability, the effects of which are difficult to express and are often hidden in the parameterization and calibration. We present a numerical experiment with the physically based hydrological model ParFlow‐CLM with which we quantify the effect of subgrid heterogeneities in headwater catchments within the cell size typicall
Authors
E. Leonarduzzi, R. M. Maxwell, Benjamin B. Mirus, P. Molnar

Expected warning times from the ShakeAlert earthquake early warning system for earthquakes in the Pacific Northwest

The ShakeAlert® earthquake early warning system has been live since October 2019 for the testing of public alerting to mobile devices in California and will soon begin testing this modality in Oregon and Washington. The Pacific Northwest presents new challenges and opportunities for ShakeAlert owing to the different types of earthquakes that occur in the Cascadia subduction zone. Many locations in
Authors
Jeffrey J. McGuire, Deborah E. Smith, Arthur D. Frankel, Erin A. Wirth, Sara K. McBride, Robert M. de Groot

Commentary: The role of geodetic algorithms for earthquake early warning in Cascadia

The ShakeAlert earthquake early warning (EEW) system issues public alerts in California and will soon extend to Oregon and Washington. The Cascadia subduction zone presents significant new challenges and opportunities for EEW. Initial publications suggested that EEW algorithms based on Global Navigation Satellite System (GNSS) data could provide improved warning for intraslab events and dramatical
Authors
Jeffrey McGuire, Sarah E. Minson, Jessica R. Murray, Benjamin A. Brooks

Characterizing stress orientations in southern Kansas

Induced seismicity predominantly occurs along faults that are optimally oriented to the local principal compressive stress direction, and the characterization of these stress orientations is an important component of understanding seismic hazards. The seismicity rate in southern Kansas rapidly increased in 2013 primarily due to the disposal of large volumes of wastewater into the Arbuckle Group. P
Authors
Robert Skoumal, Elizabeth S. Cochran, Kayla A. Kroll, Justin Rubinstein, Devin McPhillips

Slip distribution and rupture history of the August 11, 2012, double earthquakes in Ahar – Varzaghan, Iran, using joint inversion of teleseismic broadband and local strong motion data

We use combined teleseismic and strong motion data sets to investigate finite-fault slip models for a double of earthquakes that occurred on August 11, 2012, in northwestern Iran near the cities of Ahar and Varzaghan. The data include teleseismic P-waveforms retrieved from broadband seismic stations located between 30°–94° from the earthquakes and local strong motion data recorded by the Iran Stro
Authors
Atefeh Saltanatpouri, Stephen H. Hartzell, Habib Rahimi, Rahmatollah Rouhollahi, Rouholla Amiri Fard