Abstract:

The land 2-D seismic data of Beipu region in west Nanpu Sag is poor in quality.This is related to complicated surface condition and unique subsurface geological condition:1.multi-intensive reflecting boundaries and multiple Tertiary waves are the main causes of the poor qaulity;2.volcanic rocks of Tertiary System developed well and their shield action is intensive;3.the major target horizon—the Dongying Formation is of poor lithological combination with less reflecting boundaries.So it is necessary to improve tranditional seismic method,decrease randon noise and increase the ratio of signal to noise.It has been proved by practice that better results could be obtained when the maximum longitudinal shift distance on Beipu land was regulated to 4 500 m,the shield times increased to 90,exiting depth set at 9 m and detected with 5 linear multiple geophone grouping.

Key words: seismic wave, signal to noise ratio, method improvement, Beipu land