Evolution of a lateral dike intrusion revealed by relatively-relocated dike-induced earthquakes: The 2014–15 Bárðarbunga–Holuhraun rifting event, Iceland ...

Understanding dikes is vital as they serve both as bodies that build the crust and as conduits that feed eruptions, and must be monitored to evaluate volcanic hazard. During the 2014-15 Bárðarbunga rifting event, Iceland, intenseseismicity accompanied the intrusion of a ∼ 50 km lateral dike which cu...

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Bibliographic Details
Main Authors: Woods, J, Winder, T, White, RS, Brandsdóttir, B
Format: Article in Journal/Newspaper
Language:English
Published: Elsevier BV 2019
Subjects:
Online Access:https://dx.doi.org/10.17863/cam.33723
https://www.repository.cam.ac.uk/handle/1810/286414
Description
Summary:Understanding dikes is vital as they serve both as bodies that build the crust and as conduits that feed eruptions, and must be monitored to evaluate volcanic hazard. During the 2014-15 Bárðarbunga rifting event, Iceland, intenseseismicity accompanied the intrusion of a ∼ 50 km lateral dike which culminated in a 6 month long eruption. We here present relocations of earthquakes induced by the lateral dike intrusion, using cross-correlated, sub-sample relative travel times. The ∼ 100 m spatial resolution achieved reveals the complexity of the dike propagation pathway and dynamics (jerky, segmented), and allows us to address the precise relationship between the dike and seismicity, with direct implications for hazard monitoring. The spatio-temporal characteristics of the induced seismicity can be directly linked in the first instance to propagation of the tip and opening of the dike, and following this - after dike opening - indicate a relationship with magma pressure changes (i.e. dike inflation/deflation), ...