Publications
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Estimates of metals contained in abyssal manganese nodules and ferromanganese crusts in the global ocean based on regional variations and genetic types of nodules
Deep-ocean ferromanganese crusts and manganese nodules are important marine repositories for global metals. Interest in these minerals as potential resources has led to detailed sampling in many regions of the global ocean, allowing for updated estimates of their global extent. Here, we present global estimates of total tonnage as well as contained metal concentrations and tonnages for ferromangan
Authors
Kira Mizell, James R. Hein, Manda Viola Au, Amy Gartman
Seismic site characterization with shear wave (SH) reflection and refraction methods
Reflection and critically refracted seismic methods use traveltime measurements of body waves propagating between a source and a series of receivers on the ground surface to calculate subsurface velocities. Body wave energy is refracted or reflected at boundaries where there is a change in seismic impedance, defined as the product of material density and seismic velocity. This article provides pra
Authors
James A. Hunter, Heather L. Crow, William J. Stephenson, André J.-M. Pugin, Robert Williams, James B. Harris, Jackson K. Odum, Edward W Woolery
An assessment of uncertainties in VS profiles obtained from microtremor observations in the phased 2018 COSMOS blind trials
Site response is a critical consideration when assessing earthquake hazards. Site characterization is key to understanding site effects as influenced by seismic site conditions of the local geology. Thus, a number of geophysical site characterization methods were developed to meet the demand for accurate and cost-effective results. As a consequence, a number of studies have been administered perio
Authors
Michael W. Asten, Alan Yong, Sebastiano Foti, Koichi Hayashi, Antony J. Martin, William J. Stephenson, John F. Cassidy, Jacie Coleman, Robert L. Nigbor, Silvia Castellaro, Kosuke Chimoto, Ikuo Cho, Cécile Cornou, Takumi Hayashida, Manuel Hobiger, Chun-Hsiang Kuo, Albert Macau, E. Diego Mercerat, Sheri Molnar, Passakorn Pananont, Marco Pilz, Nakhorn Poovarodom, Esteban Sáez, Marc Wathelet, Hiroaki Yamanaka, Toshiaki Yokoi, Don Zhao
Waveform signatures of earthquakes located close to the subducted Gorda Plate interface
Complex seismic velocity structure near the earthquake source can affect rupture dynamics and strongly modify the seismic waveforms recorded near the fault. Fault‐zone waves are commonly observed in continental crustal settings but are less clear in subduction zones due to the spatial separation between seismic stations and the plate boundary fault. We observed anomalously long duration S waves fr
Authors
Jianhua Gong, Jeffrey McGuire
Landslides triggered by the 2002 M 7.9 Denali Fault earthquake, Alaska, USA
The 2002 M 7.9 Denali earthquake in Alaska, USA, was the largest inland earthquake in North America in nearly 150 years. The earthquake involved oblique thrusting but mostly strike-slip motion, and faults ruptured the ground surface over 330 km. Fault rupture occurred in a rugged, mountainous, subarctic environment with extensive permafrost and variable glaciation, geology, and groundwater presenc
Authors
William Schulz
Diagenesis of Vera Rubin ridge, Gale crater, Mars from Mastcam multispectral images
Images from the Mars Science Laboratory (MSL) mission of lacustrine sedimentary rocks of Vera Rubin ridge on “Mt. Sharp” in Gale crater, Mars, have shown stark color variations from red to purple to gray. These color differences crosscut stratigraphy and are likely due to diagenetic alteration of the sediments after deposition. However, the chemistry and timing of these fluid interactions is uncle
Authors
Briony H. N. Horgan, Jeffrey R. Johnson, Abigail A. Fraeman, Melissa Rice, Christina Seeger, James F. Bell, Kristen A. Bennett, Edward A. Cloutis, Lauren A. Edgar, Jens Frydenvang, John P. Grotzinger, Jonas L'Haridon, Samantha Jacob, Nicolas Mangold, Elizabeth B. Rampe, Frances Rivera-Hernandez, Vivian Z. Sun, Lucy Thompson, Danika F. Wellington
Preliminary study of correlation of natural periods and damping percentages of tall buildings in several countries
Fundamental periods (T) and critical damping percentages (ζ) of 41 tall buildings in several countries form the basis of this preliminary study. Correlation between building height and fundamental period for steel and reinforced concrete buildings clearly shows a linear variation but with a large standard deviation, most likely due to considerable variation in the designs of structural systems. No
Authors
Mehmet Çelebi
Responses of the Carquinez, California suspension bridge during the MW6.0 South Napa earthquake of August 24, 2014
The behavior of the suspension bridge in Carquinez, CA, during the Mw6.0 24 August 2014 South Napa, CA earthquake is studied using data recorded by an extensive array of accelerometers. Modes, corresponding frequencies and damping are identified and compared with previous studies that used ambient data of the deck only plus mathematical models. Data are systematically analyzed for vertical, transv
Authors
Mehmet Çelebi, S. F. Ghahari, E. Taciroglu
Zoning Verification in Mexico City Using Strong Motions of the M7.1 Puebla-Morelos Earthquake of September 19, 2017
Mexico City suffers extensive damage from large earthquakes that originate at far distances due mainly to densely built areas on a filled lakebed. Seismic design codes in Mexico recognize the site-specific issues in Mexico City by acknowledging zones that represent lakebed as being riskier compared to other Mexico City areas. At the time of the 19 September 1985 M8.1 Michoacán Earthquake, (a) the
Authors
Mehmet Çelebi, Valerie J. Sahakian, Diego Melgar, Luis Quintanar
Multi-period response spectra
Multi-period response spectra (MPRS) are incorporated in the development of seismic design ground motions in the 2020 edition of the NEHRP Recommended Seismic Provisions for New Buildings and Other Structures (2020 NEHRP Provisions) and are approved for adoption in the American Society of Civil Engineers (ASCE) Standard, Minimum Design Loads and Associated Criteria for Buildings and Other Structur
Authors
Sanaz Rezaeian, Nicolas Luco, C. A. Kircher
Exploring probabilistic seismic risk assessment to monitor the Sendai Framework for Disaster Risk Reduction
The Sendai Framework for Disaster Risk Reduction (SFDRR) calls upon the systematic collection of damage and loss data between 2015 and 2030 to monitor a number of disaster indicators. These indicators include the number of deaths, number of injured people, number of people affected by disasters, and direct economic losses. These results can then be compared with previous periods in order to track
Authors
V. Silva, A. Calderon, C. Costa, J. Dabbeek, L. Martins, A. Rao, Catalina Yepes-Estrada, A. Acevedo, H. Crowley, M. Journeay, M. Pittore
Near real-time updating of pager loss estimates
Initial alerts by PAGER (Prompt Assessment of Global Earthquakes for Response) within minutes following an earthquake include several uncertainties, mainly due to potential inaccuracies in location, depth, fault delineation, and shaking estimates. We enhance an updating framework by incorporating early reports of fatalities within the first 24 hours, or so, of an earthquake to update PAGER’s overa
Authors
Davis Engler, Kishor S. Jaiswal, Hae Young Noh, David J. Wald