Abstract:

Petroleum exploration is expanding to (super-) deeply buried strata worldwidely. Along with this trend, the hydrocarbon
accumulation in lower assemblage of the deeply-buried Jurassic strata in the southern Junggar Basin in northwest China is
becoming one of the important targets for basin,s exploration. However threre are few related studies due to relatively low degree
of exploration. This paper studies source rocks and discusses the controlling factors of hydrocarbon accumulation in the southern
Junggar Basin, inorder to provide new information on regional exploration and similar studies worldwide. Firstly, we evaluated
generation potential of the Jurassic source rocks by way of abundance, type and maturity of organic matter in combination with
geological setting. The Jurassic source rocks are of relatively good quality, having good hydrocarbon generation potential both for
oil and for gas. Secondly, the well-studied Well Xihu 1 was selected as a representative to confirm the effectiveness of the oil and
gas generation potential by analyzing hydrocarbon geochemistry. Lastly, through a hydrocarbon accumulation study, we found that
there are multiple factors that control large-scale and effective hydrocarbon accumulation of deeply-buried strata in the southern
Junggar Basin. Among them, charge intensity of hydrocarbon and physical property of reservoir were two key factors that need to
be considered in future.

Key words: southern Junggar Basin, Jurassic, deeply-buried lower assemblage, hydrocarbon accumulation, hydrocarbon
geochemistry