Using low‐frequency signals to improve imaging quality under basalt

Abstract

Wave equation numerical modeling technology is applied to study the imaging problem below screening layers of highvelocity basalt. Two simple high-velocity basalt models are designed on the basis of basalt formation characteristics. The analysis of deep-layer reflection seismic signal energy shows that low-frequency seismic signals are more capable of both penetrating thin high-velocity basalt layers and reducing diffraction noises caused by rough interfaces. The processing results of a 2-D basalt modeling and real data confirm that low-frequency signals can be used to improve the imaging quality of deep-layers under basalt.