Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 2674

Ash aggregate-rich pyroclastic density currents of the 431 CE Tierra Blanca Joven eruption, Ilopango caldera, El Salvador

The VEI 6, Tierra Blanca Joven pyroclastic sequence (30–90 km3 DRE volume), erupted from Ilopango caldera, El Salvador, in 431 CE, is the product of one of the largest eruptions of the last two millennia. The eruption devastated Central America's Mayan civilization. The eruption began with a short-lived phase of ash and pumice fall deposition and transitioned to a ‘wet’ explosive phase during whic
Authors
Richard J. Brown, Alexa R. Van Eaton, Walter Hernandez, Pearce Condren, Clare Sweeney, Pierre-Yves Tournigand, James W. Vallance

Lightning rings and gravity waves: Insights into the giant eruption plumefrom Tonga’s Hunga Volcano on 15 January 2022

On 15 January 2022, Hunga Volcano in Tonga produced the most violent eruption in the modern satellite era, sending a water-rich plume at least 58 km high. Using a combination of satellite- and ground-based sensors, we investigate the astonishing rate of volcanic lightning (>2,600 flashes min−1) and what it reveals about the dynamics of the submarine eruption. In map view, lightning locations form
Authors
Alexa R. Van Eaton, Jeff Lapierre, Sonja A. Behnke, Chris Vagasky, Christopher J. Schultz, Michael J. Pavolonis, Kristopher Bedka, Konstantin Khlopenkov

High-resolution InSAR reveals localized pre-eruptive deformation inside the crater of Agung Volcano, Indonesia

During a volcanic crisis, high-rate, localized deformation can indicate magma close to the surface, with important implications for eruption forecasting. However, only a few such examples have been reported, because frequent, dense monitoring is needed. High-resolution Synthetic Aperture Radar (SAR) is capable of achieving <1 m spatial resolution and sub-weekly revisit times, but is under-used. He
Authors
Mark Bemelmans, Juliet Biggs, Michael P. Poland, James Wookey, Susanna Ebmeier, Angela K. Diefenbach, Devy Damil Syahbana

Elucidating the magma plumbing system of Ol Doinyo Lengai (Natron Rift, Tanzania) Using satellite geodesy and numerical modeling

Ol Doinyo Lengai, located in the southern Eastern Branch of the East African Rift had several eruptive episodes with ash falls and lava flows (VEI 3) that caused damage to the nearby communities between 2007 and 2010. The volcano is remote and access is difficult. Although this volcano has been studied for decades, its plumbing system is still poorly understood, in part, because of the lack of pre
Authors
Ntambila Daud, Sarah Stamps, Maurizio Battaglia, Mong-Han Huang, Elifuraha Saria, Kang-Hyeun Ji

Flow development and entrainment in turbulent particle-laden jets

Explosive eruptions expel volcanic gases and particles at high pressures and velocities. Within this multiphase fluid, small ash particles affect the flow dynamics, impacting mixing, entrainment, turbulence, and aggregation. To examine the role of turbulent particle behavior, we conducted an analogue experiment using a particle-laden jet. We used compressed air as the carrier fluid, considering tu
Authors
Laura K. Shannon, Bianca Viggiano, Raul Bayoan Cal, Larry G. Mastin, Alexa R. Van Eaton, Stephen A. Solovitz

Volcanic and tectonic sources of seismicity near the Tanaga Volcanic Cluster, Alaska

Tanaga Island in the Central Aleutian Islands includes four stratovolcanoes: Sajaka, Tanaga, and East Tanaga in the northwest, and Takawangha in the central part of the island. Of these volcanoes, only Tanaga has a confirmed record of historical eruptive activity. We use double-difference methods to relocate Tanaga Island earthquakes from the period 2003–2017 to gain insight into volcanic and tect
Authors
Kevin Lally, Jackie Caplan-Auerbach, John Power

2019 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory

The Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 17 volcanic centers in Alaska in 2019. The most notable volcanic activity was an eruption of Shishaldin Volcano, featuring eruptive activity that produced lava flows, lahars, and ash. Weak explosive activity also took place at Great Sitkin Volcano and
Authors
Tim R. Orr, Cheryl E. Cameron, Hannah R. Dietterich, James P. Dixon, Max L. Enders, Ronni Grapenthin, Alexandra M. Iezzi, Matthew W. Loewen, John A. Power, Cheryl Searcy, Gabrielle Tepp, Liam Toney, Christopher F. Waythomas, Aaron G. Wech

Volcanic earthquake catalog enhancement using integrated detection, matched-filtering, and relocation tools

Volcanic earthquake catalogs are an essential data product used to interpret subsurface volcanic activity and forecast eruptions. Advances in detection techniques (e.g., matched-filtering, machine learning) and relative relocation tools have improved catalog completeness and refined event locations. However, most volcano observatories have yet to incorporate these techniques into their catalog-bui
Authors
Darren Tan, David Fee, Alicia J. Hotovec-Ellis, J. Pesicek, Matthew M. Haney, John Power, T. Girona

Garnet stability in arc basalt, andesite, and dacite—An experimental study

Garnet’s stability in arc magmas and its influences on their differentiation were explored experimentally in a typical basalt, andesite, and dacite at conditions of 0.9–1.67 GPa, 800–1300 °C, with 2–9 wt.% added H2O, and with oxygen fugacity buffered near Re + O2 = ReO2 (~ Ni-NiO + 1.7 log10 bars). Garnet did not grow at 0.9 GPa in any of the compositions, even with garnet seeds added to facilitat
Authors
Dawnika Blatter, Thomas W. Sisson, W. Ben Hankins

Weak degassing from remote Alaska volcanoes characterized with a new airborne Imaging DOAS instrument and a suite of in situ sensors

Gas emissions from volcanoes occur when volatile species exsolve from magmatic and hydrothermal systems and make their way to the surface. Measurements of emitted gases therefore provide insights into volcanic processes. On 16 July 2021, we made airborne measurements of weak gas plumes emitted from four remote Alaska volcanoes: Iliamna Volcano, Mount Douglas, Mount Martin, and Mount Mageik. Integr
Authors
Christoph Kern, Peter J. Kelly

It begins with curiosity—How do scientists learn from volcanoes?

This poster uses photographs of scientists in action to introduce the principles of critical thinking and curiosity-driven science as they relate to the study of volcanoes. Captions align with educational “Next Generation Science Standards” and include job titles and tasks to increase career awareness among students and their teachers. The poster is available in both English and Spanish.
Authors
Elizabeth G. Westby, Lisa M. Faust

2018 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory

The Alaska Volcano Observatory responded to eruptions, considerable and minor volcanic unrest, and seismic events at 15 volcanic centers in Alaska during 2018. The most notable volcanic activity came from Mount Cleveland, which had continuing intermittent dome growth and ash eruptions, and Mount Veniaminof, Great Sitkin Volcano, and Semisopochnoi Island, the three of which had minor eruptions. Thi
Authors
Cheryl E. Cameron, Tim R. Orr, James P. Dixon, Hannah R. Dietterich, Christopher F. Waythomas, Alexandra M. Iezzi, John A. Power, Cheryl Searcy, Ronni Grapenthin, Gabrielle Tepp, Kristi L. Wallace, Taryn M. Lopez, Kimberly Degrandpre, John M. Perreault