Teleseisms and microseisms on an ocean-bottom distributed acoustic sensing array
Ethan F. Williams, Maria R. Fernandez-Ruiz, Regina Magalhaes, Roel Vanthillo, Zhongwen Zhan, Miguel Gonzalez-Herraez, Hugo F. Martins
Received Date: 20th May 19
Sparse seismic instrumentation in the oceans limits our understanding of deep Earth dynamics and submarine earthquakes. Distributed acoustic sensing (DAS), an emerging technology that converts optical fiber to seismic sensors, allows us to leverage pre-existing submarine telecommunication cables for seismic monitoring. Here we report observations of a teleseismic earthquake, local surface gravity waves, and microseism along a 4192-sensor ocean-bottom DAS array offshore Belgium. We successfully recover P- and S-wave phases from the 2018-08-19 Mw8.2 Fiji deep earthquake in the 0.01-1 Hz frequency band. We also observe in-situ how opposing groups of ocean surface gravity waves generate double-frequency seismic Scholte waves, as described by the Longuet-Higgins theory of microseism generation. These results suggest great potential of DAS in next-generation submarine seismic networks.
Read in full at EarthArXiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.