GEOCHEMICAL EFFECTS OF CRUDE OIL MIGRATION IN THE NORTH TARIM BASIN, XINJIANG

Some successes were achieved when six new migration parameters of light hydrocarbon fingerprints for crude oil as well as lighter heavy hydrocarbon, biomarkers and other migration parameters were applied to the geochemical effect study of crude oil migration in North Tarim area. The hydrocarbon generated in the Late Hercynian is all related to the Ordovician source rocks reflected from its migration indexes. It must be the product of a large scale lateral migration northward along the Hercynian plane of unconformity from the oil source regions of the Awati and Manjiaer Depressions to the Shaya Uplift. The migration indexes show that the hydrocarbon generated in the Himalayan not only is related to the Ordovician source rocks but also has some relations with the Triassic-Jurassic source rocks. It can also accept continental hydrocarbon lateral migration southward from the Kuche Depression on the north.