| The degree of oil and gas exploration in the Qiangtang Basin is low. To further identify the potential of Jurassic Sowa Formation source rocks, this study conducted total organic carbon, extraction, chromatography-mass spectrometry, Ro determination, and isotopic analysis on the Puruogang daily profile outcrop. It aims to define the source rock characteristics and formation environment of the Sowa Formation in the Puruogangri area. The results show that the total organic carbon content of Sowa Formation source rocks in the study area ranges from 0.22 to 2.16 wt%, with an average of 0.65 wt%. The depositional environment is reductive marine facies, with the parent material contributed by higher plants and algae. Kerogen isotopes indicate type III organic matter. Influenced by Paleogene volcanic activity, the source rocks are at a high maturity stage, with Ro values ranging from 1.85% to 3.51%. Comprehensive analysis indicates that Sowa Formation source rocks, centered around intrusive rocks (former heat sources) and within the radiation range of the Puruogang profile, are gas-dominated. In areas distant from intrusive rocks, Sowa Formation source rocks can produce small amounts of crude oil. |