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Publications

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Laboratory tests of three Z‐Land Fairfield Nodal 5‐Hz, three‐component sensors

We conduct a number of laboratory tests at the Albuquerque Seismological Laboratory to verify the self‐noise and fidelity in which 3 three‐component Fairfield Nodal Z‐Land, Generation 2, 5‐Hz sensors are able to record seismic signals. In addition to the incoherent self‐noise of the sensors, we estimate the sensitivity of the units in digital volts/m/s, the damping, and the free period. These thre
Authors
Adam T. Ringler, Robert E. Anthony, M.S Karplus, Austin Holland, David C. Wilson

Characterizing the sponge grounds of Grays Canyon, Washington, USA

Deep-sea sponge grounds are relatively understudied ecosystems that may provide key habitats for a large number of fish and invertebrates including commercial species. Glass sponge grounds have been discovered from the tropics to polar regions but there are only a few places with high densities of dictyonine sponges. Dictyonine glass sponges have a fused skeleton, which stays intact when they die
Authors
Abby N. Powell, M. Elizabeth Clarke, Erica Fruh, Jason Chaytor, Henry M. Reiswig, Curt E. Whitmire

DDT and related compounds in pore water of shallow sediments on the Palos Verdes Shelf, California, USA

For nearly two and a half decades following World War II, production wastes from the world's largest manufacturer of technical DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) were discharged into sewers of Los Angeles County. Following treatment, the wastes were released via a submarine outfall system to nearshore coastal waters where a portion accumulated in shallow sediments of
Authors
Robert P. Eganhouse, Erica L. DiFilippo, James Pontolillo, William H. Orem, Paul C. Hackley, Brian Edwards

Reductive dechlorination rates of 4,4′-DDE (1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene) in sediments of the Palos Verdes Shelf, CA

Wastes from the world's largest manufacturer of DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) were released into the Los Angeles County municipal sewer system from 1947 to 1971. Following primary treatment, the effluent was discharged through a submarine outfall system whereupon a portion of the DDT and associated degradation products were deposited in sediments of the Palos Ve
Authors
Robert P. Eganhouse, Christopher R. Sherwood, James Pontolillo, Brian Edwards, Patrick J. Dickhudt

Seagrass impact on sediment exchange between tidal flats and salt Marsh, and the sediment budget of shallow bays

Seagrasses are marine flowering plants that strongly impact their physical and biological surroundings and are therefore frequently referred to as ecological engineers. The effect of seagrasses on coastal bay resilience and sediment transport dynamics is understudied. Here we use six historical maps of seagrass distribution in Barnegat Bay, USA, to investigate the role of these vegetated surfaces
Authors
Carmine Donatelli, Neil Kamal Ganju, Sergio Fagherazzi, Nicoletta Leonardi

Preface to the Focus Section on the Collaboratory for the Study of Earthquake Predictability (CSEP): New results and future directions

The Collaboratory for the Study of Earthquake Predictability (CSEP; Jordan, 2006) carries out fully prospective tests of earthquake forecasts, using fixed and standardized statistical tests and authoritative data sets, to assess the predictive skill of forecast models and to make objective comparisons between models. CSEP conducts prospective experiments at four testing centers around the world, a
Authors
Andrew J. Michael, Maximillian J. Werner

Ensemble smoothed seismicity models for the new Italian Probabilistic Seismic Hazard Map

We develop a long‐term (a few decades or longer) earthquake rate forecast for Italy based on smoothed seismicity for incorporation in the 2017–2018 Italian Probabilistic Seismic Hazard Maps (IPSHM). Because the earthquake rate models from previous IPSHM were computed using source zones that were drawn around seismicity and tectonic provinces, the present model will be the first introduction of the
Authors
Aybige Akinci, Morgan P. Moschetti, Matteo Taroni

Reexamination of the subsurface fault structure in the vicinity of the 1989 moment-magnitude-6.9 Loma Prieta earthquake, central California, using steep-reflection, earthquake, and magnetic data

We reexamine the geometry of the causative fault structure of the 1989 moment-magnitude-6.9 Loma Prieta earthquake in central California, using seismic-reflection, earthquake-hypocenter, and magnetic data. Our study is prompted by recent interpretations of a two-part dip of the San Andreas Fault (SAF) accompanied by a flower-like structure in the Coachella Valley, in southern California. Initially
Authors
Edward Zhang, Gary S. Fuis, Rufus D. Catchings, Daniel S. Scheirer, Mark Goldman, Klaus Bauer

Broadband ground‐motion simulation of the 2011 Mw 6.2 Christchurch, New Zealand, earthquake

This study presents the details and results of hybrid broadband (0–10 Hz) ground‐motion simulations for the 2011 MwMw 6.2 Christchurch, New Zealand, earthquake. The simulations utilize a 3D velocity model and a kinematic source model with stochastic realizations of the slip amplitude, rise time, and rake angle. The resulting ground motions capture the salient basin amplification effects that are s
Authors
Hoby N. T. Razafindrakoto, Brendon A. Bradley, Robert Graves

On the feasibility of real-time mapping of the geoelectric field across North America

A review is given of the present feasibility for accurately mapping geoelectric fields across North America in near-realtime by modeling geomagnetic monitoring and magnetotelluric survey data. Should this capability be successfully developed, it could inform utility companies of magnetic-storm interference on electric-power-grid systems. That real-time mapping of geoelectric fields is a challenge
Authors
Jeffrey J. Love, E. Joshua Rigler, Anna Kelbert, Carol A. Finn, Paul A. Bedrosian, Christopher C. Balch

Injection-induced moment release can also be aseismic

The cumulative seismic moment is a robust measure of the earthquake response to fluid injection for injection volumes ranging from 3100 to about 12 million m3. Over this range, the moment release is limited to twice the product of the shear modulus and the volume of injected fluid. This relation also applies at the much smaller injection volumes of the field experiment in France reported by Guglie
Authors
Arthur McGarr, Andrew J. Barbour

Storm impacts on hydrodynamics and suspended-sediment fluxes in a microtidal back-barrier estuary

Recent major storms have piqued interest in understanding the responses of estuarine hydrodynamics and sediment transport to these events. To that end, flow velocity, wave characteristics, and suspended-sediment concentration (SSC) were measured for 11 months at eight locations in Chincoteague Bay, MD/VA, USA, a shallow back-barrier estuary. Daily breezes and episodic storms generated sediment-res
Authors
Daniel J. Nowacki, Neil K. Ganju