Publications
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Interpreting and reporting 40Ar/39Ar geochronologic data
The 40Ar/39Ar dating method is among the most versatile of geochronometers, having the potential to date a broad variety of K-bearing materials spanning from the time of Earth’s formation into the historical realm. Measurements using modern noble-gas mass spectrometers are now producing 40Ar/39Ar dates with analytical uncertainties of ∼0.1%, thereby providing precise time constraints for a wide ra
Authors
Allen J. Schaen, Brian R. Jicha, Kip V. Hodges, Pieter Vermeesch, Mark E. Stelten, Cameron M. Mercer, David Phillips, Tiffany Rivera, Fred Jourdan, Erin L. Matchan, Sidney R. Hemming, Leah E. Morgan, Simon P. Kelley, William S. Cassata, Matt T. Heizler, Paulo M. Vasconcelos, Jeff A. Benowitz, Anthony A.P. Koppers, Darren F. Mark, Elizabeth M. Niespolo, Courtney J. Sprain, William E. Hames, Klaudia F. Kuiper, Brent D. Turrin, Paul R. Renne, Jake Ross, Sebastian Nomade, Hervé Guillou, Laura E. Webb, Barbara A. Cohen, Andrew T. Calvert, Nancy Joyce, Morgan Ganderød, Jan Wijbrans, Osamu Ishizuka, Huaiyu He, Adán Ramirez, Jörg Pfänder, Margarita Lopez-Martínez, Huaning Qiu, Brad S. Singer
Response: Commentary: Variability in Shelf Sedimentation in Response to Fluvial Sediment Supply and Coastal Erosion Over the Past 1,000 Years in Monterey Bay, CA, United States
No abstract available.
Authors
Joe Carlin, Jason A. Addison, Amy Wagner, Valerie Evelyn Schwartz, Jamie Hayward, Victoria Severin
Quantifying gas emissions associated with the 2018 rift eruption of Kīlauea Volcano using ground-based DOAS measurements
Starting on 3 May 2018, a series of eruptive fissures opened in Kīlauea Volcano’s lower East Rift Zone (LERZ). Over the course of the next 3 months, intense degassing accompanied lava effusion from these fissures. Here, we report on ground-based observations of the gas emissions associated with Kīlauea’s 2018 eruption. Visual observations combined with radiative transfer modeling show that ultravi
Authors
Christoph Kern, Allan Lerner, Tamar Elias, Patricia Nadeau, Lacey Holland, Peter J. Kelly, Cynthia Werner, Laura E. Clor, Michael Cappos
Geochemical modeling of iron and aluminum precipitation during mixing and neutralization of acid mine drainage
Geochemical modeling of precipitation reactions in the complex matrix of acid mine drainage is fundamental to understanding natural attenuation, lime treatment, and treatment procedures that separate constituents for potential reuse or recycling. The three main dissolved constituents in acid mine drainage are iron, aluminum, and sulfate. During the neutralization of acid mine drainage (AMD) by mix
Authors
D. Kirk Nordstrom
The prevalence and significance of offset magma reservoirs at arc volcanoes
Determining the spatial relations between volcanic edifices and their underlying magma storage zones is fundamental for characterizing long-term evolution and short-term unrest. We compile centroid locations of upper crustal magma reservoirs at 56 arc volcanoes inferred from seismic, magnetotelluric, and geodetic studies. We show that magma reservoirs are often horizontally offset from their assoc
Authors
Allan H. Lerner, Daniel O'Hara, Leif Karlstrom, Susanna K. Ebmeier, Kyle R. Anderson, Shaul Hurwitz
Observations on the structure of Surtsey
Comparison of investigations of the 1979 and 2017 cored boreholes coupled with continued observations of the dynamic surface of Surtsey has modified our concepts of the subsurface structure of the volcano. A geometrical analysis of the 2017 vertical and inclined cores indicates that near-surface layering dips westerly, indicating that the boreholes are located inside the Surtur crater. In subaeria
Authors
James G. Moore, Marie D. Jackson
Modeling groundwater inflow to the new crater lake at Kīlauea Volcano, Hawaiʻi
During the 2018 eruption of Kīlauea Volcano, Hawai'i, scientists relied heavily on a conceptual model of explosive eruptions triggered when lava‐lake levels drop below the water table. Numerical modeling of multiphase groundwater flow and heat transport revealed that, contrary to expectations, liquid water inflow to the drained magma conduit would likely be delayed by months to years, owing to the
Authors
Steven E. Ingebritsen, Ashton F. Flinders, James P. Kauahikaua, Paul A. Hsieh
Source model for Sabancaya volcano constrained by DInSAR and GNSS surface deformation observation
Sabancaya is the most active volcano of the Ampato-Sabancaya Volcanic Complex (ASVC) in southern Perú and has been erupting since 2016. The analysis of ascending and descending Sentinel-1 orbits (DInSAR) and Global Navigation Satellite System (GNSS) datasets from 2014 to 2019 imaged a radially symmetric inflating area, uplifting at a rate of 35 to 50 mm/yr and centered 5 km north of Sabancaya. The
Authors
Gregorio Boixart, Luis Cruz, Rafael Miranda, Pablo Euillades, Leonardo Euillades, Maurizio Battaglia
The 1951 eruption of Mount Lamington, Papua New Guinea: Devastating directed blast triggered by small-scale edifice failure
The catastrophic explosion of Mount Lamington volcano, Papua New Guinea on January 21, 1951 produced a devastating pyroclastic density current (PDC) that knocked down dense tropical rainforest over an area of 230 km2 and killed approximately 3000 people. We present results of a field reinvestigation of the 1951 PDC deposit combined with an analysis of the available photographs and eyewitness accou
Authors
Alexander Belousov, Marina Belousova, Richard P. Hoblitt, Herman Patia
Major-oxide and trace-element geochemical data from rocks collected on Little Sitkin Island, from Little Sitkin Volcano, Alaska
During the 2005 summer field season, geologists Michelle Coombs, Christina Neal, and Jessica Larsen from the University of Alaska, Fairbanks and the U.S. Geological survey, Alaska Volcano Observatory (AVO) conducted fieldwork on Little Sitkin Island in the western Aleutians of Alaska. The primary purpose of the fieldwork was to install geophysical networks for volcano monitoring. As part of this e
Authors
Jessica Larsen, Christina A. Neal, Cheryl E. Cameron
Radiocarbon dating of silica sinter and postglacial hydrothermal activity in the El Tatio geyser field
The El Tatio geothermal field in the Chilean Altiplano contains hydrothermal silica sinter deposits overlaying glacial and volcanic units, providing an opportunity to constrain the timing of deglaciation and volcanic activity in an area with sparse absolute chronologies. We obtained 51 new radiocarbon ages and δ13C values on the organic material trapped in these sinter deposits. Based on the δ13C
Authors
Carolina Munoz Saez, Michael Manga, Shaul Hurwitz, Silvina Salgter, Dakota Churchill, Martin Reich, David Damby, Diego Morata
Climate from the McMurdo Dry Valleys, Antarctica, 1986 – 2017: Surface air temperature trends and redefined summer season
The weather of the McMurdo Dry Valleys, Antarctica, the largest ice‐free region of the Antarctica, has been continuously monitored since 1985 with currently 14 operational meteorological stations distributed throughout the valleys. Because climate is based on a 30‐year record of weather, this is the first study to truly define the contemporary climate of the McMurdo Dry Valleys. Mean air temperatu
Authors
Maciej Obryk, P. T. Doran, A. G. Fountain, Monique Myers, C. P. McKay