Publications
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An interface for simulating radiative transfer in and around volcanic plumes with the Monte Carlo radiative transfer model McArtim
This report describes two software tools that, when used as front ends for the three-dimensional backward Monte Carlo atmospheric-radiative-transfer model (RTM) McArtim, facilitate the generation of lookup tables of volcanic-plume optical-transmittance characteristics in the ultraviolet/visible-spectral region. In particular, the differential optical depth and derivatives thereof (that is, weighti
Authors
Christoph Kern
Structure of the Hat Creek graben region: Implications for the structure of the Hat Creek graben and transfer of right-lateral shear from the Walker Lane north of Lassen Peak, northern California, from gravity and magnetic anomalies
Interpretation of magnetic and new gravity data provides constraints on the geometry of the Hat Creek Fault, the amount of right-lateral offset in the area between Mt. Shasta and Lassen Peak, and confirmation of the influence of pre-existing structure on Quaternary faulting. Neogene volcanic rocks coincide with short-wavelength magnetic anomalies of both normal and reversed polarity, whereas a mar
Authors
Victoria E. Langenheim, Robert C. Jachens, Michael A. Clynne, L. J. Patrick Muffler
By
Energy and Minerals 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
Asthenosphere–lithosphere interactions in Western Saudi Arabia: Inferences from 3He/4He in xenoliths and lava flows from Harrat Hutaymah
Extensive volcanic fields on the western Arabian Plate have erupted intermittently over the last 30 Ma following emplacement of the Afar flood basalts in Ethiopia. In an effort to better understand the origin of this volcanism in western Saudi Arabia, we analyzed3He/4He, and He, CO2 and trace element concentrations in minerals separated from xenoliths and lava flows from Harrat Hutaymah, supplemen
Authors
Kevin Konrad, David W. Graham, Carl Thornber, Robert A. Duncan, Adam J. R. Kent, Abdulla Al-Amri
Post-eruptive inflation of Okmok Volcano, Alaska, from InSAR, 2008–2014
Okmok, a ~10-km wide caldera that occupies most of the northeastern end of Umnak Island, is one of the most active volcanoes in the Aleutian arc. The most recent eruption at Okmok during July-August 2008 was by far its largest and most explosive since at least the early 19th century. We investigate post-eruptive magma supply and storage at the volcano during 2008–2014 by analyzing all available sy
Authors
Feifei Qu, Zhong Lu, Michael P. Poland, Jeffrey T. Freymueller, Qin Zhang, Hyung-Sup Jung
Dome growth at Mount Cleveland, Aleutian Arc, quantified by time-series TerraSAR-X imagery
Synthetic aperture radar imagery is widely used to study surface deformation induced by volcanic activity; however, it is rarely applied to quantify the evolution of lava domes, which is important for understanding hazards and magmatic system characteristics. We studied dome formation associated with eruptive activity at Mount Cleveland, Aleutian Volcanic Arc, in 2011–2012 using TerraSAR-X imagery
Authors
Teng Wang, Michael P. Poland, Zhong Lu
The 2014-2015 Pāhoa lava flow crisis at Kīlauea Volcano, Hawai‘i: Disaster avoided and lessons learned
Lava flow crises are nothing new on the Island of Hawai‘i, where their destructive force has been demonstrated repeatedly over the past several hundred years. The 2014–2015 Pāhoa lava flow crisis, however, was unique in terms of its societal impact and volcanological characteristics. Despite low effusion rates, a long-lived lava flow whose extent reached 20 km (the longest at Kīlauea Volcano in th
Authors
Michael P. Poland, Tim R. Orr, James P. Kauahikaua, Steven R. Brantley, Janet L. Babb, Matthew R. Patrick, Christina A. Neal, Kyle R. Anderson, Loren Antolik, Matthew K. Burgess, Tamar Elias, Steven Fuke, Pauline Fukunaga, Ingrid A. Johanson, Marian Kagimoto, Kevan P. Kamibayashi, Lopaka Lee, Asta Miklius, William Million, Cyril J. Moniz, Paul G. Okubo, Andrew Sutton, T. Jane Takahashi, Weston A. Thelen, Willam Tollett, Frank A. Trusdell
Constraints on the source parameters of low-frequency earthquakes on the San Andreas Fault
Low-frequency earthquakes (LFEs) are small repeating earthquakes that occur in conjunction with deep slow slip. Like typical earthquakes, LFEs are thought to represent shear slip on crustal faults, but when compared to earthquakes of the same magnitude, LFEs are depleted in high-frequency content and have lower corner frequencies, implying longer duration. Here we exploit this difference to estima
Authors
Amanda M. Thomas, Gregory C. Beroza, David R. Shelly
At the foot of the smoking mountains: The 2014 scientific investigations in the Islands of the Four Mountains
An interdisciplinary research team conducted archaeological, geological, and biological investigations in the Islands of the Four Mountains, Alaska during the summer of 2014 as part of a three-year project to study long-term geological and ecological patterns and processes with respect to human settlement. Researchers investigated three archaeological sites on Chuginadak Island (SAM-0014, SAM-0016
Authors
Virginia Hatfield, Kale Bruner, Dixie West, Arkady Savinetsky, Olga Krylovich, Bulat Khasanov, Dmitry Vasyukov, Zhanna Antipushina, Mitsuru Okuno, Susan Crockford, Kirsten Nicolaysen, Breanyn MacInnes, Lyman Persico, Pavel Izbekov, Christina A. Neal, Thomas Bartlett, Lydia Loopesko, Anne Fulton
Dimensionless erosion laws for cohesive sediment
A method of achieving a dimensionless collapse of erosion-rate data for cohesive sediments is proposed and shown to work well for data collected in flume-erosion tests on mixtures of sand and mud (silt plus clay sized particles) for a wide range of mud fraction. The data collapse corresponds to a dimensional erosion law of the form E∼(τ−τc)mE∼(τ−τc)m, where EE is erosion rate, ττ is shear stress,
Authors
Joseph S. Walder
Monogenetic volcanoes fed by interconnected dikes and sills in the Hopi Buttes volcanic field, Navajo Nation, USA
Although monogenetic volcanic fields pose hazards to major cities worldwide, their shallow magma feeders (<500 m depth) are rarely exposed and, therefore, poorly understood. Here, we investigate exposures of dikes and sills in the Hopi Buttes volcanic field, Arizona, to shed light on the nature of its magma feeder system. Shallow exposures reveal a transition zone between intrusion and eruption wi
Authors
James D. Muirhead, Alexa R. Van Eaton, Giuseppe Re, James D. L. White, Michael H. Ort
Geochemical characterization and dating of R tephra, a post-glacial marker bed in Mount Rainier National Park, Washington, U.S.A.
The oldest postglacial lapilli–ash tephra recognized in sedimentary records surrounding Mount Rainier (Washington State, USA) is R tephra, a very early Holocene deposit that acts as an important stratigraphic and geochronologic marker bed. This multidisciplinary study incorporates tephrostratigraphy, radiocarbon dating, petrography, and electron microprobe analysis to characterize R tephra. Tephra
Authors
Mary Samolczyk, James W. Vallance, Joel Cubley, Gerald Osborn, Douglas H. Clark
Apatite fission-track evidence for regional exhumation in the subtropical Eocene, block faulting, and localized fluid flow in east-central Alaska
The origin and antiquity of the subdued topography of the Yukon–Tanana Upland (YTU), the physiographic province between the Denali and Tintina faults, are unresolved questions in the geologic history of interior Alaska and adjacent Yukon. We present apatite fission-track (AFT) results for 33 samples from the 2300 km2 western Fortymile district in the YTU in Alaska and propose an exhumation model t
Authors
Cynthia Dusel-Bacon, Charles R. Bacon, Paul B. O'Sullivan, Warren C. Day