Insights Into Volcanic Rift-Tectonic Fault Interactions From Moment Tensor Analysis of the Seismicity Prior to the 2021 and 2022 Fagradalsfjall Eruptions in Iceland
Description:
The two fissure eruptions at Fagradalsfjall volcano (located in the Reykjanes Peninsula in southwestern Iceland) in March 2021 and August 2022 were preceded by intense seismicity up to magnitude Mw 5.7. Thousands of events were reported by the Icelandic Meteorological Office (IMO), and many inhabitants in and around Reykjavík felt many intermediate and large-magnitude events. We retrieved the seismic moment tensor for around 100 events recorded before the 2021 and the 2022 eruptions inverting waveforms recorded by the IMO broadband seismic network. Although it is assumed that earthquakes in the Reykjanes Peninsula are due to strike-slip displacements of an array of sub-parallel N-S-trending faults in so-called bookshelf-type faulting, our moment tensors showed more diversity in the seismic sources in addition to N-S strike-slip faults. We performed a cross-correlation analysis of waveforms verifying that source parameter diversity agrees with different waveform clusters. Our goal is to understand the cause of those non-pure double-couple strike-slip mechanisms in the context of an imminent fissure eruption in a complex oblique rift system.
Session: Earthquake Source Parameters: Theory, Observations and Interpretations
Type: Oral
Date: 4/18/2023
Presentation Time: 05:15 PM (local time)
Presenting Author: Félix Rodríguez Cardozo
Student Presenter: No
Invited Presentation:
Authors
Félix Rodríguez Cardozo Presenting Author Corresponding Author frodriguezcardozo@gmail.com University of South Florida |
Jochen Braunmiller jbraunmiller@usf.edu University of South Florida |
Kristín Jónsdóttir kristin.jonsdottir@vedur.is Icelandic Meteorological Office |
Vala Hjörleifsdóttir vala.hjorleifsdottir@or.is Orkuveita Reykjavíkur |
Gerardo Mendo gmendoperez@gmail.com Universidad Nacional Autónoma de México |
Yesim Cubuk Sabunku yesim@vedur.is Icelandic Meteorological Office |
Glenn Thompson thompsong@usf.edu University of South Florida |
|
|
Insights Into Volcanic Rift-Tectonic Fault Interactions From Moment Tensor Analysis of the Seismicity Prior to the 2021 and 2022 Fagradalsfjall Eruptions in Iceland
Category
Earthquake Source Parameters: Theory, Observations and Interpretations