Abstract:Time lapse seismic acquisition is the most direct and effective technical means for tapping remaining oil potential. Most of China's old oil fields, including Huizhou A oilfield in the eastern South China Sea, have not implemented time lapse seismic acquisition. In order to clarify the distribution and movement patterns of oil and water in Huizhou A Oilfield, which has entered the stage of ultra-high water cut and high recovery, under the conditions of orthogonal collection of old 3D data and new 2D data, a mathematical operation method was used to perform dual directional non repetitive time-lapse seismic processing on the primary and secondary 3D data, achieving the goal of reducing the cost of time-lapse seismic acquisition and predicting the distribution of remaining oil. After drilling verification, the remaining oil prediction results are consistent with the drilling results, and this method can be used as a reference for the promotion of offshore oil fields.