Sequence Stratigraphy Research And Subtle Trap Recognition In The Centre Part Of Zunggar Basin

With the relatively higher degree of prospecting, the subtle trap in Zungar Basin was considered as an important exploration direction. Zungar Basin belongs to the large-scale landlocked depression basin in Jurassic Period, the water body of lake is not deep, the slope is relatively slow, the whole is a river-lake delta system, characteristics of multiple cycle and source help the lithology trap to develop.Base on the structure background , sequence stratigraphy and depositional system of Jurassic Period has been studied . An efficient method to discovery subtle trap in the Centre Part of Zungar basin has been found.In this paper, The division of sequence in outcrop, log well and seismic and sequence interface and depositional system and system track was detailed discussed. Analyzing the different advantages of every method, the seismic data was directly used to divid third-order sequence. Log well sequence analysis method is suitable for four or above rank sequence study.The outcrop sequence analysis method is suitable for the study of sequence interior structure, depositional system.Zungar basin is a superposed basin developed on Hercynian basis. The deposition of Jurassic Period in the Centre part is controlled by the ancient uplift. The ancient uplift was formed in the end of early Juassic period , developed in the end of latterly Juassic Period , buried in Cretaceous Period -early Tertiary Period, transformed and adjusted in Tertiary Period-Quaternary Period lately. The ancient uplift has the important influence to the development of subtle trap in the Centre Part of Zungar basin.Base on outcrop and log well and seismic section, seven sequences and two Super sequences and one Mega sequence were founded. Zungar Basin subsides wholly in later period of Indosinian.The deposition of formation of Badaowan, Sangonghe and Xisanyao...