Origin of Lawn Hollow and Hole and Their Disposal;

For further deepening the exploration process to find commercial oil and gas flow, it is necessary to study the hydrocarbon-bearing system of Tiancao sag.

Tiancao sag develops many sets of source rocks,but the main source rock is still unclear,and the report about the evaluation of source rock has not been seen.

The reservoir rock type of Lower Cretaceous age in Tiancao depression of YingenEjinaqi basin consisteds mainly of feldspar litharenite which is characterized by high contents of lithic debris,by lass for feldspar and least for quartz.

In order to evaluate the petroleum prospecting potential of the Tiancao depression, two set of source rocks from Bayingebi Formation and Suhongtu Formation of Lower Cretaceous respectively were collected for studying their geological and geochemical characteristics and thermal evolution history.

Located in the northwest of the Cretaceous rift basin group in Yingen Ejinaqi basin, the tectono-sedimentary evolution of Tiancao depression involves three main periods, the first period is the occurrence and development of the rift in earlier Cretaceous, the second period is the sagging during later Cretaceous and the third period is squeezing and uplifting during Tertiary and Quaternary.

Evaluation of denudation of structural unconformable surface for Paleozoic upper Devonian bottom and Permian bottom in Caohu depression of Tarim basin;

Carboniferous sequence stratigraphy and changes of sea level in Caohu depression of Tarim Basin;

Taking the Caohu depression as an example, the Cahou, Hercynian, Yansan and Himalayan oil-gas systems and the producing hydrocarbon sub-system are plotted and described using the time limit of the most important three structural movements and the cosmical or conical shape of the hydrocar.