1. Complex paths of magma propagation at Fernandina (Galápagos): The coexistence of circumferential and radial dike intrusion during the January 2020 eruption.
- Author
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Galetto, Federico
- Subjects
- *
SYNTHETIC aperture radar , *VOLCANIC eruptions , *MAGMAS , *RADIAL flow - Abstract
Understanding paths of magma propagation is fundamental to infer how magma is transported from magma reservoir to the surface during eruptions. Here has been investigated the 2020 circumferential eruption that occurred on the upper east flank of Fernandina volcano (Galápagos), using Interferometric Synthetic Aperture Radar (InSAR) data and geodetic modelling. Results show that most of the deformation is related to a radial intrusion that propagated southward, evolving from sill-like intrusion beneath the caldera to radial and dike-like lower on the volcano flank. No deformation in the coherent area immediately to the east of the 2020 circumferential eruptive fissures is spatially correlated with these fissures, which might be associated with an ephemeral circumferential dike that have shared with the radial dike the same intra-caldera intruded sill. This eruption is the first documented event in the Galápagos where circumferential and radial dikes were intruded simultaneously, suggesting that magma in these volcanoes can propagate from the same intrusion in two different directions, with distinct geometries at the same time. The volume of the radial dike is higher than the inferred erupted volume. This fact suggests that magma mainly flowed into the radial dike, potentially explaining why the circumferential eruption only lasted for 9 h. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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