Results 81 to 90 of about 5,469 (201)

Interplay of Tectonics and Topography Facilitated Sudden Dyke Intrusion in 2022 at São Jorge Island, Azores

Geophysical Research Letters, Volume 53, Issue 6, 28 March 2026.
Abstract Oblique slow rifting in a hotspot setting has created a distributed volcanic zone in the central part of the Azores but it's unclear what causes focusing of magma upflow under the islands within a wide plate boundary deformation zone. For São Jorge Island, we use a three‐dimensional finite element model to evaluate crustal stress from the ...
J. D’Araújo, A. Hooper, M. Lazecky, F. Sigmundsson, F. Albino, T. Ferreira, J. L. Gaspar   +6 more
wiley   +1 more source

Trigger mechanism and propagation dynamics of pyroclastic density currents at basaltic volcanoes

Communications Earth & Environment
Pyroclastic density currents (PDCs) are among the deadliest manifestations of volcanic eruptions, commonly associated with volcanoes characterized by intermediate to felsic magma compositions and related to eruption column collapse, lateral blasts, or ...
Francesco Zuccarello, Daniele Andronico, Paola Del Carlo, Mattia de’ Michieli Vitturi, Alessio Di Roberto, Gaetana Ganci, Boris Behncke, Tomaso Esposti Ongaro, Francesco Ciancitto, Annalisa Cappello   +9 more
doaj   +1 more source

Behaviours of pyroclastic and analogue materials, in dry and wet environments, for use in experimental modelling of pyroclastic density currents

Volcanica
Modelling pyroclastic density currents (PDCs) is a challenging yet essential element of hazard assessment. PDCs are unpredictable and internal processes are often difficult to measure directly.
Nemi Walding, Rebecca Williams, Pete Rowley, Natasha Dowey, Daniel Parsons, Anna Bird   +5 more
doaj   +1 more source

Teleseismic Radial Anisotropy Reveals a Sill‐Dominated Magma Reservoir Beneath the Valles Caldera, New Mexico

Geophysical Research Letters, Volume 53, Issue 6, 28 March 2026.
Abstract The Valles Caldera (VC), one of the largest Quaternary silicic calderas in North America, formed by explosive rhyolitic eruptions. Seismic studies suggest a crustal magmatic reservoir beneath the caldera with low‐velocity anomalies, but resolving the detailed geometry of localized melt requires constraints from seismic anisotropy.
Gaoshan Guo, Haiqiang Lan, Tao Xu, Qinya Liu   +3 more
wiley   +1 more source

Revaluating the Vertical Velocity and Density Structure of Dilute Pyroclastic Density Currents

, 2023
Dilute pyroclastic density currents (dilute PDCs) are frequent and hazardous volcanic phenomena. Better mitigating against PDC hazards requires understanding of the vertical velocity and density structures inside flows and how these are modified during flow runout, particle sedimentation, air entrainment and buoyancy reversal.
Uhle, D., Ardo, J., Lube, G., Jones, J.
openaire   +2 more sources

Modeling the Transport and Dispersion of Volcanic Co‐PDC Ash Clouds Using NAME: An Evaluation of Source Geometry and Mass Eruption Rate

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 6, 28 March 2026.
Abstract Pyroclastic density currents (PDCs) are gravity currents that frequently form during explosive volcanic eruptions. These ground‐hugging density currents consist of high‐temperature mixtures of pyroclasts (e.g., ash, pumice), lithics, and gas.
M. Hagenbourger, F. M. Beckett, T. J. Jones, S. L. Engwell   +3 more
wiley   +1 more source

Volcanic Ash Affected by Lightning During the Hunga 2022 Eruption

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 5, 16 March 2026.
Abstract The 15 January 2022 eruption of Hunga volcano (Kingdom of Tonga) produced the most lightning ever documented during an explosive eruption to date. This study estimates the mass of erupted tephra that may be structurally or electromagnetically affected by the lightning, based upon lightning peak current, channel length, and ash plume particle ...
Kimberly Genareau, Joali Paredes‐Mariño, Shane J. Cronin, Sebastian S. Harkema, Christopher J. Schultz, Kelley M. Murphy, Aaron R. Naeger   +6 more
wiley   +1 more source

Volcanoes Erupt Stressed Quartz Crystals

Geophysical Research Letters, 2019
Volcanic eruptions are energetic events driven by the imbalance of magmatic forces. The magnitudes of these forces remain poorly constrained because they operate in regions that are inaccessible, either underground or dangerous to approach.
K. S. Befus, M. Manga, C. Stan, N. Tamura   +3 more
doaj   +1 more source

Supplemental Material: Long-runout pyroclastic density currents: Analysis and implications

, 2022
<p>Supplemental figures, detailed information on the Great Basin ignimbrites and the paleovalleys, a summary of the database and the characteristics of the pyroclastic density currents, and the statistical model used. </p>
et al., Olivier Roche
openaire   +1 more source

Repository - Unraveling Transient Dynamics in Particle-Laden Density Currents: Insights into Dilute Pyroclastic Density Current Runout

, 2023
This the data repository of the AGU monograph entitled "Unraveling Transient Dynamics in Particle-Laden Density Currents: Insights into Dilute Pyroclastic Density Current Runout"
Breard, Eric, Cerminara, Matteo, Dufek, Josef, O'Donnell, Sean   +3 more
openaire   +1 more source