关键词: 番禺低隆区, 先存断裂体系, 断裂演化, 断裂控洼, 源—汇系统, 烃源岩, 珠江口盆地

Abstract:  The exploration potential of the Panyu low uplift in the Pearl River Mouth basin (PRMB) is considerable. However, the level of research remains low and is limited to individual depressions, lacking systematic analysis of the impact of fault structures on the sedimentation of depressions and the source-sink system. This limitation hinders subsequent exploration and development activities. Therefore, this paper systematically analyzes the relationship and evolutionary sequence of the source-sink response under the control of tectonic activity in the Panyu low uplift area of the PRMB, based on the latest 3D seismic data and drilling information. The Cenozoic fault activity in the Panyu low uplift area exhibits significant zonation and periodicity under the influence of two existing fault systems, NE-NEE and NW-NWW, during the Late Mesozoic. In the Early Wenchang period, the faulting controlled the depression, with NE-NEE direction dominating in the western region and EW direction in the eastern region, while the fault activity increased during the Wenchang period compared to the Enping period. Three types of fault-controlled depressions developed within the area: Migration-type, combination-type, and inheritance-type. The source-sink system in the area utilizes the felsic granite from the uplift area and the ancient Pearl River as the material source with steep slope faults, gentle slope transition trenches, and reverse fault steps acting as transportation pathways, while half-graben depressions serve as the sedimentation zones. In the Early Wenchang period, a source-sink system dominated by nearby material sources and large source areas developed in small lake basins; In the Late Wenchang period, a coexistence of nearby and distant material sources in the small source area of large lake basins occurred; And during the Enping period, a large lake basin system developed with distant sources in the western region and nearby sources in the eastern region. Overall, the highest quality semi-deep lake facies hydrocarbon source rocks developed in the Late Wenchang period characterized by high tectonic activity rates and low material source supply; Large-scale distant deltaic sedimentary sand bodies widely developed in the Enping Formation period marked by low tectonic activity rates and high material source supply, the source rocks and the sand bodies formed the most favorable vertically combination of source, reservoir and cap rocks.

Key words: Panyu low uplift, pre-existing faults, fault evolution, fault-controlled depression, source-sink system, source rock, Pearl River Mouth basin