Onshore-offshore seismic experiment uses air-gun arrays as seismic sources, permanent and portable land stations and ocean bottom seismometers to form a signal record array. Such experiment has been carried out many times in the northern South China Sea, and layout of portable stations was always a key for the success in such a field experiment. This paper is based on the onshore-offshore seismic experiment in Hainan island during 2011. It summarizes the processes and matters that need attention during deploying portable stations, and analyzes air-gun signals received by portable stations on three different types of basements. We find that the received air-gun signals were closely related to the stability of the basement and the ambient noise. When using exposed abundant basic rock as the basement, portable stations acquired high signal-to-noise ratio (SNR), and long duration of the waveform and more concentrated energy. When the basement was large semi-floating rockmass on a mountaintop, the portable stations received general SNR, and long duration of waveform. When the basement was rocks exposed in the sedimentary layer, the signal received by portable station performed lower SNR, longer duration of waveform, and decentralized energy; even the arrival time was hard to identify. From the processed profiles, we conclude that clearly seismic phase and more accurate arrival time were easily acquired when exposed abundant basic rock was used as the basement.
JIA Shao-Gong
,
LIN Wei
,
CHEN Jian-Chao
,
XU Hui-Long
,
QIU Hua-Lin
. Layout of portable stations and signal analysis in an onshore-offshore seismic experiment[J]. Journal of Tropical Oceanography, 2012
, 31(3)
: 48
-57
.
DOI: 10.11978/j.issn.1009-5470.2012.03.007
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