Prestack amplitude preservation focusing and imaging technology for specific geologic body underground

The invention belongs to a geophysical exploration technology, and relates to a prestack amplitude preservation focusing and imaging technology for a specific geologic body underground. According to the invention, seismic data is acquired, conventional processing such as prestack noise elimination, de-convolution and first arrival blanking, and a geologic body at a specific depth underground can be accurately imaged by using the prestack amplitude preservation focusing and imaging technology. A corresponding focusing parameter can be estimated according to the spatial position of the specific geologic body underground, the focusing parameter is applied to prestack amplitude preservation focusing offset for the geologic body, and an accurate imaging result can be acquired. Provided by the invention is a high-precision imaging method for the specific geologic body underground, a problem that special geologic bodies such as a salt dome, a buried hill and a fracture at the medium depth underground are difficult to be imaged is solved, geometric diffusion effects in seismic wave propagation can be eliminated, and an offset section with relatively preserved amplitude is acquired.