Abstract:A set of sand and gravel reservoirs with quasi in-situ sedimentary genesis are commonly developed on the surface of ancient buried mountain oil and gas reservoirs, which have good physical pro-perties and high productivity but complex distribution patterns. It is urgent to carry out reservoir distribution prediction to support the development of buried mountain oil and gas reservoirs. This article takes the Archean buried hill in Bohai A oilfield as an example and adopts the approach of "discussing the present and the past" to establish a prototype model of sand and gravel sedimentation in the source area. Based on the restoration of micro ancient landforms and fully utilizing the low-frequency response cha-racteristics of 3D seismic data, the distribution prediction of sand and gravel reservoirs in the ancient buried hill erosion source area has been achieved. The following understanding has been obtained: (1) The sedimentation of sand and gravel in the erosion source area is controlled by local terrain and landforms, forming different sedimentary combination patterns in mountain areas, inter mountain depre-ssions, and inter mountain valleys; (2) On the basis of the impression method, the fine characterization of micro paleogeomorphology is achieved using the technique of amplifying the difference in layer slope attributes. Based on the low-frequency seismic data, seismic attribute analysis is carried out, and the corresponding relationship between attribute distribution and micro geomorphic units is used to further judge the rationality of reservoir distribution prediction results. The research results of Oilfield A show that the distribution of sand and gravel in its erosion source area conforms to the "mountain eroded river front alluvial fan" combination model developed in mountainous areas. The sand and gravel in the mountain valleys are in a continuous strip shape, while the sand and gravel in the peak and ridge areas are poorly developed and distributed in discontinuous patches. The sand and gravel in the geomorphic units of the mountain slope are distributed in continuous patches.