Abstract: Research Significance Cenozoic igneous rocks are well developed in the southern pinghu slope zone of Xihu Depression. Local warming caused by magmatic activity has an important influence on the thermal evolution of source rocks and the formation of secondary pores in sandstone reservoirs, and magmatic activity is also the "pointer" of regional tectonic movement. Purpose and methods Based on 3d seismic data, seismic facies, volcanic mechanism and distribution horizon of igneous rocks in Pingnan area were identified and characterized. Results and conclusions The following three understandings were obtained in combination with previous studies on regional tectonic evolution: 1) Seismic facies of igneous rocks in the study area can be divided into volcanic channel facies, eruptive facies, overflow facies and intrusive facies. Shield volcanic mechanism and mound volcanic mechanism are mainly developed, and longjing movement accompanied by volcanic activity in the late Miocene. 2) The local warming of magmatic activity is favorable to the thermal evolution of source rocks and the formation of secondary pores in deep consolidated sandstone reservoirs; 3) There are five lithologic traps related to magmatic activity, low amplitude drape anticline and fault compound traps in the study area.