Publications
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Instability of Hawaiian volcanoes
Hawaiian volcanoes build long rift zones and some of the largest volcanic edifices on Earth. For the active volcanoes on the Island of Hawai‘i, the growth of these rift zones is upward and seaward and occurs through a repetitive process of decades-long buildup of a magma-system head along the rift zones, followed by rapid large-scale displacement of the seaward flank in seconds to minutes. This la
Authors
Roger P. Denlinger, Julia K. Morgan
The dynamics of Hawaiian-style eruptions: A century of study
This chapter, prepared in celebration of the Hawaiian Volcano Observatoryʼs centennial, provides a historical lens through which to view modern paradigms of Hawaiian-style eruption dynamics. The models presented here draw heavily from observations, monitoring, and experiments conducted on Kīlauea Volcano, which, as the site of frequent and accessible eruptions, has attracted scientists from around
Authors
Margaret T. Mangan, Katharine V. Cashman, Donald A. Swanson
A century of studying effusive eruptions in Hawaii
The Hawaiian Volcano Observatory (HVO) was established as a natural laboratory to study volcanic processes. Since the most frequent form of volcanic activity in Hawai‘i is effusive, a major contribution of the past century of research at HVO has been to describe and quantify lava flow emplacement processes. Lava flow research has taken many forms; first and foremost it has been a collection of bas
Authors
Katherine V. Cashman, Margaret T. Mangan
40Ar/39Ar geochronology, paleomagnetism, and evolution of the Boring volcanic field, Oregon and Washington, USA
The 40Ar/39Ar investigations of a large suite of fine-grained basaltic rocks of the Boring volcanic field (BVF), Oregon and Washington (USA), yielded two primary results. (1) Using age control from paleomagnetic polarity, stratigraphy, and available plateau ages, 40Ar/39Ar recoil model ages are defined that provide reliable age results in the absence of an age plateau, even in cases of significant
Authors
Robert J. Fleck, Jonathan T. Hagstrum, Andrew T. Calvert, Russell C. Evarts, Richard M. Conrey
By
Energy and Minerals Mission Area, Natural Hazards Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Volcano Hazards Program, Volcano Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Growth and degradation of Hawaiian volcanoes
The 19 known shield volcanoes of the main Hawaiian Islands—15 now emergent, 3 submerged, and 1 newly born and still submarine—lie at the southeast end of a long-lived hot spot chain. As the Pacific Plate of the Earth’s lithosphere moves slowly northwestward over the Hawaiian hot spot, volcanoes are successively born above it, evolve as they drift away from it, and eventually die and subside beneat
Authors
David A. Clague, David R. Sherrod
2014 update of the U.S. national seismic hazard maps
We held 8 regional and topical workshops across the U.S. to gather information for these maps. The maps were available to the public for comment during a 60-day period. A Steering Committee (9 experts) was assembled to review the inputs and results and provide additional insights. The maps have been presented at several professional meetings.
In this talk we discuss:
(1) CEUS, (2) WUS (outside
Authors
Mark D. Petersen, Morgan P. Moschetti, Peter M. Powers, Charles S. Mueller, Kathleen M. Haller, Arthur D. Frankel, Yuehua Zeng, Sanaz Rezaeian, Stephen C. Harmsen, Oliver S. Boyd, Edward H. Field, R Chen, Kenneth S. Rukstales, Nicolas Luco, Russell L. Wheeler, Anna H. Olsen
Triggered aseismic slip adjacent to the 6 February 2013 Mw 8.0 Santa Cruz Islands megathrust earthquake
Aseismic or slow slip events have been observed in many subduction zones, but whether they affect the occurrence of earthquakes or result from stress changes caused by nearby events is unclear. In an area lacking direct geodetic observations, inferences can be made from seismological studies of co-seismic slip, associated stress changes and the spatiotemporal nature of aftershocks. These observati
Authors
Gavin P. Hayes, Kevin P. Furlong, Harley M. Benz, Matthew W. Herman
Stable stress‐drop measurements and their variability: Implications for ground‐motion prediction
We estimate the arms‐stress drop, Graphic, (Hanks, 1979) using acceleration time records of 59 earthquakes from two earthquake sequences in eastern Honshu, Japan. These acceleration‐based static stress drops compare well to stress drops calculated for the same events by Baltay et al. (2011) using an empirical Green’s function (eGf) approach. This agreement supports the assumption that earthquake a
Authors
Thomas C. Hanks, Annemarie S. Baltay, Gregory C. Beroza
Use of fragile geologic structures as indicators of unexceeded ground motions and direct constraints on probabilistic seismic hazard analysis
We present a quantitative procedure for constraining probabilistic seismic hazard analysis results at a given site, based on the existence of fragile geologic structures at that site. We illustrate this procedure by analyzing precarious rocks and undamaged lithophysae at Yucca Mountain, Nevada. The key metric is the probability that the feature would have survived to the present day, assuming that
Authors
J. W. Baker, John W. Whitney, Thomas C. Hanks, Norman A. Abramson, Mark P. Board
Re‐estimated effects of deep episodic slip on the occurrence and probability of great earthquakes in Cascadia
Mazzotti and Adams (2004) estimated that rapid deep slip during typically two week long episodes beneath northern Washington and southern British Columbia increases the probability of a great Cascadia earthquake by 30–100 times relative to the probability during the ∼58 weeks between slip events. Because the corresponding absolute probability remains very low at ∼0.03% per week, their conclusion i
Authors
Nicholas M. Beeler, Evelyn A. Roeloffs, Wendy McCausland
The 2011 M = 9.0 Tohoku oki earthquake more than doubled the probability of large shocks beneath Tokyo
1] The Kanto seismic corridor surrounding Tokyo has hosted four to five M ≥ 7 earthquakes in the past 400 years. Immediately after the Tohoku earthquake, the seismicity rate in the corridor jumped 10-fold, while the rate of normal focal mechanisms dropped in half. The seismicity rate decayed for 6–12 months, after which it steadied at three times the pre-Tohoku rate. The seismicity rate jump and d
Authors
Shinji Toda, Ross S. Stein
The 1960 tsunami on beach-ridge plains near Maullín, Chile: Landward descent, renewed breaches, aggraded fans, multiple predecessors
The Chilean tsunami of 22 May 1960 reamed out a breach and built up a fan as it flowed across a sparsely inhabited beach-ridge plain near Maullín, midway along the length of the tsunami source. Eyewitnesses to the flooding, interviewed mainly in 1988 and 1989, identified levels that the tsunami had reached on high ground, trees, and build- ings. The maximum levels fell, from about 10 m to 2 m, bet
Authors
Brian F. Atwater, Marco Cisternas, E. Yulianto, A. Prendergast, K. Jankaew, A. Eipert, Warnakulasuriya Fernando, Iwan Tejakusuma, Ignacio Schiappacasse, Yuki Sawai