Abstract:

Based on drilling,logging and seismic data,principles of high resolution sequence stratigraphy and correlation method using datum cycle as reference framework are used in this paper.Five drilling datum mid-term cycles and five corresponding seismic sequences are recognized and the framework of high resolution sequence stratigraphy correlation is established in Penglaizhen Formation of Upper Jurassic in Xinchang of West Sichuan Depression according to formation denudation phenomena,remained deposits,short-term cycle superimposed pattern,seismic reflection end type and important variation of reflective character.It is pointed out that the main body of Penglaizhen Formation deposited in the position of transititional part from deltaic subwater-plain to river mouth bar during the process of late descending-early rising of the mid-term datum and mostly occurred in both sides of sequence boundary.Seismic response of the gas-bearing sand bodies was used for lateral prediction.Consequently,the accuracy of predicting time-space distribution of the favorable sand bodies and description of smaller sand bodies is significantly increased.

Key words: Xinchang, Penglaizhen Formation, datum cycle, high resolution, sequence stratigraphy, lateral prediction