Fossil intermediate-depth earthquakes in subducting slabs linked to differential stress release
Scambelluri M, Pennacchioni G, Gilio M, Bestmann M, Plumper O, Nestola F (2017)
Publication Status: Published
Publication Type: Journal article, Original article
Publication year: 2017
Journal
Publisher: NATURE PUBLISHING GROUP
Book Volume: 10
Pages Range: 960-+
Journal Issue: 12
DOI: 10.1038/s41561-017-0010-7
Abstract
The cause of intermediate-depth (50-300 km) seismicity in subduction zones is uncertain. It is typically attributed either to rock embrittlement associated with fluid pressurization, or to thermal runaway instabilities. Here we document glassy pseudotachylyte fault rocks-the products of frictional melting during coseismic faulting-in the Lanzo Massif ophiolite in the Italian Western Alps. These pseudotachylytes formed at subduction-zone depths of 60-70 km in poorly hydrated to dry oceanic gabbro and mantle peridotite. This rock suite is a fossil analogue to an oceanic lithospheric mantle that undergoes present-day subduction. The pseudotachylytes locally preserve high-pressure minerals that indicate an intermediate-depth seismic environment. These pseudotachylytes are important because they are hosted in a near-anhydrous lithosphere free of coeval ductile deformation, which excludes an origin by dehydration embrittlement or thermal runaway processes. Instead, our observations indicate that seismicity in cold subducting slabs can be explained by the release of differential stresses accumulated in strong dry metastable rocks.
Authors with CRIS profile
Involved external institutions
University of Padua / Universita degli Studi di Padova
Italy (IT)
University of Genova / Università degli Studi di Genova
Italy (IT)
Universiteit Utrecht (UU) / Utrecht University
Netherlands (NL)
Italy (IT)
University of Genova / Università degli Studi di Genova
Italy (IT)
Universiteit Utrecht (UU) / Utrecht University
Netherlands (NL)
How to cite
APA:
Scambelluri, M., Pennacchioni, G., Gilio, M., Bestmann, M., Plumper, O., & Nestola, F. (2017). Fossil intermediate-depth earthquakes in subducting slabs linked to differential stress release. Nature Geoscience, 10(12), 960-+. https://dx.doi.org/10.1038/s41561-017-0010-7
MLA:
Scambelluri, Marco, et al. "Fossil intermediate-depth earthquakes in subducting slabs linked to differential stress release." Nature Geoscience 10.12 (2017): 960-+.
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