Abstract:

 Traditionally，the Cambrian abnormal bodies in the southern Yingmaili swell were considered to be the reflections of MiddleCambrian salt tectonics. However, we found that there are multiple options to explain these large anomalous bodies. It is possible that the carbonate buildups exist in the main part of the folded structures and were thickened by the latter faults and formed large overlying composite folds. Faults and cracks are extremely developed inside the Cambrian folds and can greatly improve Cambrian dolomitite reservoir properties. They are very conducive to the oil and gas accumulation. The basement rifts can connect effectively with oil source, and the MiddleCambrian shale or mudstone can form good capping formations that are well closed. A comprehensive analysis on the southern Yingmaili area indicates that the Cambrian largescale fold structures possess favorable conditions for hydrocarbon accumulation and storage, and are favorable for forming large and mediumscale oil and gas fields. The Cambrian carbonatite buildup will be one of the new hydrocarbon exploration potential fields in the Tarim basin.

Key words:

Key words: Tarim basin；North Tarim uplift；Yingmaili swell；Cambrian；carbonatite buildup；algal reef；hydrocarbon reservoir