A future for drifting seismic networks
1 Earth Sciences Department
University College London
London, WC1E 6BT, UK
2 Geosciences Department
Princeton NJ 08544, USA
3 Institute of Geophysics and Planetary Physics
EOS, Trans. Am. Geoph. Union, 2006, 87 (31), 305 & 307
Scripps Institution of Oceanography
La Jolla, CA 92093, USA
In the last few decades seismologists have mapped out elastic
wavespeeds of the Earth's interior with often perplexing if not always
uncontested detail. Earthquake sources used in seismic tomography lie
mostly on plate boundaries; receivers mostly on dry land. The uneven
coverage resulting from this fundamentally inadequate source-station
distribution leaves large volumes inside the Earth entirely unsampled.
Placing seismic stations on the ocean bottom is often touted as the
only solution. The MERMAID project (Mobile Earthquake Recorder in
Marine Areas by Independent Divers) is a radical low-cost alternative
that uses passively drifting autonomous hydrophones with a now proven
potential to record hundreds of distant earthquakes over their
projected life span.
- Figure 01
Example of poor resolution of
mantle structure in the southern hemisphere and elsewhere
due to the absence of seismic stations in the ocean.
- Figure 02
The MERMAID-001 prototype. The
hydrophone protrudes from the middle right.
- Figure 03
A P wave from a magnitude 6.0
earthquake at 46 degrees detected at 700 m
depth by the hydrophone onboard MERMAID-001.
Last modified: Wed Apr 12 23:06:25 EDT 2023