Analysis on causes of differences in physical properties of Jurassic crude oil around Fukang depression, Junggar Basin

According to the differences in physical properties of Jurassic crude oil around Fukang depression, geochemical characteristics of oil are analyzed from five zones. The results show that differences in organic matter and biodegradation are the causes of differences in physical properties. Crude oil in Ganhe and Santai oilfield come from Permian sapropel source rocks. Because of biodegradation, crude oil in Santai oilfield was heavier. Due to multistage charging and biodegradation, crude oil in Fudong slope is characterized by mixed with normal density. The light oil in Fubei slope and Fukang depression belong to the products of Jurassic humic source rocks.