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Title: Explosive-effusive volcanic eruption transitions caused by sintering.
Silicic volcanic activity has long been framed as either violently explosive or gently effusive. However, recent ob- servations demonstrate that explosive and effusive behavior can occur simultaneously. Here, we propose that rhyolitic magma feeding subaerial eruptions generally fragments during ascent through the upper crust and that effusive eruptions result from conduit blockage and sintering of the pyroclastic products of deeper cryptic frag- mentation. Our proposal is supported by (i) rhyolitic lavas are volatile depleted; (ii) textural evidence supports a pyroclastic origin for effusive products; (iii) numerical models show that small ash particles !10−5 m can diffusive- ly degas, stick, and sinter to low porosity, in the time available between fragmentation and the surface; and (iv) inferred ascent rates from both explosive and apparently effusive eruptions can overlap. Our model reconciles previously paradoxical observations and offers a new framework in which to evaluate physical, numerical, and geochemical models of Earth’s most violent volcanic eruptions.
Authors:
; ; ; ;
Award ID(s):
1725186
Publication Date:
NSF-PAR ID:
10301238
Journal Name:
Science advances
Volume:
6
Issue:
39
Page Range or eLocation-ID:
eaba7940
ISSN:
2375-2548
Sponsoring Org:
National Science Foundation
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