Study on Characteristic Variability of Weak Signal in High Density Seismic Acquisition

Chen Wujin¹ and Wu Anchu¹

Abstract

The seismic signal received by sensors is very weak because of absorption and attenuation by subsurface and deep layer during signal propagating. The high frequency component was much more serious absorbed and attenuated than low frequency component. The key issues for high density seismic acquisition are to receive and identify low reflection coefficient or high frequency weak signal. In this paper the relationship between weak signal and subsurface, dominant frequency, offset and deep target layer was analyzed based on a typical elastic-viscoelastic earth model. Due to cut off frequency exists, it is very difficult to show the advantages of broad band frequency in high density seismic acquisition in the area with strong subsurface attenuation and low S/N ratio. Good condition excitation can improve weak signal energy and give more contribution to broaden frequency band. The effective reflection coefficient can be better presented in small and middle receiver- source offset and can be well extracted to guide high density data acquisition and processing.

AAPG Search and Discovery Article #90188 ©GEO-2014, 11th Middle East Geosciences Conference and Exhibition, 10-12 March 2014, Manama, Bahrain