UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Reconstructing magma failure and the degassing network of dome-building eruptions

Lavallee, Y; Benson, PM; Heap, MJ; Hess, K-U; Flaws, A; Schillinger, B; Meredith, PG; (2013) Reconstructing magma failure and the degassing network of dome-building eruptions. Geology , 41 (4) pp. 515-518. 10.1130/G33948.1. Green open access

[img]
Preview
Text
Benson_GEOLOGY-S-12-00762.pdf - Accepted version

Download (12MB) | Preview

Abstract

Volcanic eruptions are regulated by the rheology of magmas and their ability to degas. Both detail the evolution of stresses within ascending subvolcanic magma. But as magma is forced through the ductile-brittle transition, new pathways emerge as cracks nucleate, propagate, and coalesce, constructing a permeable network. Current analyses of magma dynamics center on models of the glass transition, neglecting important aspects such as incremental strain accommodation and (the key monitoring tool of) seismicity. Here, in a combined-methods study, we report the first high-resolution (20 μm) neutron-computed tomography and microseismic monitoring of magma failure under controlled experimental conditions. The data reconstruction reveals that a competition between extensional and shear fracturing modes controls the total magnitude of strain-to-failure and importantly, the geometry and efficiency of the permeable fracture network that regulates degassing events. Extrapolation of our findings yields magma ascent via strain localization along conduit margins, thereby providing an explanation for gas-and-ash explosions along arcuate fractures at active lava domes. We conclude that a coupled deformation-seismicity analysis holds a derivation of fracture mechanisms and network, and thus holds potential application in forecasting technologies.

Type: Article
Title: Reconstructing magma failure and the degassing network of dome-building eruptions
Open access status: An open access version is available from UCL Discovery
DOI: 10.1130/G33948.1
Publisher version: https://doi.org/10.1130/G33948.1
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Science & Technology, Physical Sciences, Geology, STRAIN LOCALIZATION, FRACTURE, VOLCANO, DECOMPRESSION, PERMEABILITY, EARTHQUAKES, GROWTH, COLIMA, LAVAS, MODEL
UCL classification: UCL
UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/10117714
Downloads since deposit
8Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item