Analysis of heavy oil genesis and oil source correlation in Tuyuke Oilfield of Tuha Basin

Tuyuke oilfield is a heavy oil pool. There are different opinions about genesis of heavy oil and its oil\|source at present. The genesis of heavy oil and oil source sequence are analyzed according to the geochemical parameters of crude oil, oil and source rock correlation and fluid\|inclusion. The crude oil in Tuyuke oilfield suffered from biodegradation, and the genesis reached middle degree. The crude oil in the process of petroleum accumulation is normal mature hydrocarbon. Oil and gas mainly came from source of Permian system in the northern sags and the oil maturity is about 0.8%-0.9%. The petroleum in Tuyuke oilfield migrated and accumulated mainly in the end of Triassic and Lower Jurassic. The lifting in the end of Triassic caused oil pool of biodegradation. Tuyuke oilfield was located in the environment of shallow water or lifting, and the oil pool suffered from biodegradation.