Trans-crustal structural control of CO2-rich extensional magmatic systems revealed at Mount Erebus Antarctica

0558416 - GFÚ 2023 RIV GB eng J - Journal Article
Hill, Graham J. - Wannamaker, P. E. - Maris, V. - Stodt, J. A. - Kordy, M. A. - Unsworth, M. - Bedrosian, P. A. - Wallin, E. L. - Uhlmann, D. F. - Ogawa, Y. - Kyle, P.
Trans-crustal structural control of CO2-rich extensional magmatic systems revealed at Mount Erebus Antarctica.
Nature Communications. Roč. 13, č. 1 (2022), č. článku 2989. E-ISSN 2041-1723
Grant - others:AV ČR(CZ) LQ100121901
Program: Prémie Lumina quaeruntur
Institutional support: RVO:67985530
Keywords : Ross Island * seismic tomography * eruptive history * Erebus volcano * mantle
OECD category: Volcanology
Impact factor: 16.6, year: 2022
Method of publishing: Open access
https://www.nature.com/articles/s41467-022-30627-7

Erebus volcano, Antarctica, with its persistent phonolite lava lake, is a classic example of an evolved, CO2-rich rift volcano. Seismic studies provide limited images of the magmatic system. Here we show using magnetotelluric data that a steep, melt-related conduit of low electrical resistivity originating in the upper mantle undergoes pronounced lateral re-orientation in the deep crust before reaching shallower magmatic storage and the summit lava lake. The lateral turn represents a structural fault-valve controlling episodic flow of magma and CO2 vapour, which replenish and heat the high level phonolite differentiation zone. This magmatic valve lies within an inferred, east-west structural trend forming part of an accommodation zone across the southern termination of the Terror Rift, providing a dilatant magma pathway. Unlike H2O-rich subduction arc volcanoes, CO2-dominated Erebus geophysically shows continuous magmatic structure to shallow crustal depths of < 1 km, as the melt does not experience decompression-related volatile supersaturation and viscous stalling.
Permanent Link: http://hdl.handle.net/11104/0332141