Jacques BRIVES
Imaging Pyrenean lithosphere with ambient noise correlation
Supervisor:
Stehly Sebastien ; Univsity of Grenoble – ISTerre
Major Results
Ambient noise dataset from an spread of 435 stations over 1500km2 over the Pyrenean Mauleon Basin were correlated, in order to increase surface wave dispersion measurements and the ray coverage inside the array.
Abstract
Ambient seismic noise correlation method (C1) has proved to be an efficient way to retrieve surface wave propagation between any station pair. This method is now extensively used for seismic tomography and monitoring and benefits from the development of dense array. In this study we propose to revisit a dataset of broadband stations deployed across and around the Pyrenees massif between 2011 and 2013 (MAUPASACQ dataset). Using correlation of correlation method (C2) we are able to improve both the quality and the amount of surface wave dispersion mesurements between synchronous and asynchronous station pairs.
This allow us to drastically improve the ray coverage inside an around the massif and finally to obtain high resolution group velocity maps from 6s to 40s of period. Combined with C1, C2 method unveils sharp geologic structures within the massif between two asynchronous deployment and also allow us to have a much greater coverage of the Golf de Gascogne.
figure
Large-scale reconstruction of the Tethys–Atlantic area for the 270 Ma (a), 180 Ma (b), 140 Ma (c), and 100 Ma (d) periods. Modified from Angrand et al., 2020, Solid Earth.
PhD Thesis: Tomographie des Pyrénées par corrélation de bruit d’ordre supérieur. Application multi-échelle.
PhD Thesis: Tomographie des Pyrénées par corrélation de bruit d’ordre supérieur. Application multi-échelle.
Jacques Brives. Tomographie des Pyrénées par corrélation de bruit d’ordre supérieur. Application multi-échelle. Sciences de la Terre et de l’Univers et de l’Environnement, Université Grenoble, Alpes, 2020.
keywords: Sismologie, Tomographie, Pyrénées, Bruit ambiant, Ondes de surface, Maupasacq