Real-time assessment of potential seismic migration within a monitoring network using Red-flag SARA

TitleReal-time assessment of potential seismic migration within a monitoring network using Red-flag SARA
Publication TypeJournal Article
Year of Publication2019
AuthorsTan CTing, Taisne B, Neuberg J, Basuki A
Journal Jounral of Volcanology and Geothermal Research
Volume384
Pagination 31-47
Date Published10/2019
ISSN0377-0273
Accession NumberWOS:000488333100003
Abstract

Magma opening new fluid pathways through the crust can generate migrating seismic sources following the trail of the magma. By using Seismic Amplitude Ratio Analysis (SARA), it is possible to detect this seismic migration simply from the amplitudes of continuous data recorded at different stations in a network, without having to do any picking of seismic phases. In this study, we present a modified method - Red-flag SARA, which adapts SARA for real-time monitoring. Red-flag SARA provides a quantitative tool to analyse amplitude ratios between stations in a network and detect temporal changes in these ratios. Since such changes imply seismic source location variations, Red-flag SARA is a handy tool during seismic crises to quickly answer the question of whether seismic activity, and therefore magma, is migrating or not. We tested Red-flag SARA on synthetic data and validated it using real data from two volcanoes - Piton de la Fournaise, Reunion Island, and Gede, Indonesia, for three scenarios: 1) magma migration ending as intrusion, 2) migration leading to eruption and 3) a burst of seismicity with no magma migration. (C) 2019 The Authors. Published by Elsevier B.V.

DOI10.1016/j.jvolgeores.2019.07.004