HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Detecting seismic activity with a covariance matrix analysis of data recorded on seismic arrays

Abstract : Modern seismic networks are recording the ground motion continuously at the Earth's surface, providing dense spatial samples of the seismic wavefield. The aim of our study is to analyse these records with statistical array-based approaches to identify coherent time-series as a function of time and frequency. Using ideas mainly brought from the random matrix theory, we analyse the spatial coherence of the seismic wavefield from the width of the covariance matrix eigenvalue distribution. We propose a robust detection method that could be used for the analysis of weak and emergent signals embedded in background noise, such as the volcanic or tectonic tremors and local microseismicity, without any prior knowledge about the studied wavefields. We apply our algorithm to the records of the seismic monitoring network of the Piton de la Fournaise volcano located at La Réunion Island and composed of 21 receivers with an aperture of ∼15 km. This array recorded many teleseismic earthquakes as well as seismovolcanic events during the year 2010. We show that the analysis of the wavefield at frequencies smaller than ∼0.1 Hz results in detection of the majority of teleseismic events from the Global Centroid Moment Tensor database. The seismic activity related to the Piton de la Fournaise volcano is well detected at frequencies above 1 Hz.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03581673
Contributor : Nathalie Pothier Connect in order to contact the contributor
Submitted on : Sunday, February 20, 2022 - 12:32:58 PM
Last modification on : Thursday, April 7, 2022 - 1:58:15 PM
Long-term archiving on: : Saturday, May 21, 2022 - 6:10:50 PM

File

ggv531.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

L. Seydoux, N. M. Shapiro, J. de Rosny, F. Brenguier, M. Landès. Detecting seismic activity with a covariance matrix analysis of data recorded on seismic arrays. Geophysical Journal International, Oxford University Press (OUP), 2016, 204, pp.1430-1442. ⟨10.1093/gji/ggv531⟩. ⟨insu-03581673⟩

Share

Metrics

Record views

51

Files downloads

4