Sedimentary Facies and Favorable Areas Prediction of the Middle Cambrian Gaotai Formation in the Eastern Sichuan Basin
[Objective]The Sichuan Basin has abundant oil and gas resources. The breakthrough of the Sinian Deng-ying and Cambrian Longwangmiao Formations reveals the huge exploration potential of deep oil and gas resources in the Sichuan Basin. However,the extent of research and exploration of the Cambrian Gaotai Formation in the eastern Sichuan Basin is typically low. Research between stratigraphy and sedimentary facies characteristics of the Gaotai For-mation can provide a basis for the next step of oil and gas exploration and deployment.[Methods]The basic geologi-cal research on the sequence stratigraphy,sedimentary facies characteristics,and distribution of the Gaotai Forma-tion can provide the basis for future oil and gas exploration and deployment. Based on drilling,logging,outcrop pro-file,core,and seismic data,a comprehensive study on the sequence lithofacies paleogeo.graphy of the Cambrian Gaotai Formation in eastern Sichuan has been conducted.[Results]The results show that Gaotai Formation can be divided into three third-order sequences (SQ1-SQ3) and six fourth-order sequences (SSQ1-SSQ6). During the sedi-mentary period of Gaotai Formation,the carbonate restricted platform sedimentary environment was developed. From west to east,four sedimentary subfacies developed successively:mixed tidal flat,tidal flat,lagoon and inner plat-form beach. The Gaotai Formation developed with a silty dolomite reservoir,which is characterized by thin thickness,strong heterogeneity,and "medium-low porosity and low permeability".[Conclusions]The favourable reservoirs in the study area are located in the dorsal spreading area influenced by tectonic activity and hydrothermal fluids. Tidal flat subfacie (dolomite tidal flat microfacies) is a favourable exploration zone in the western of eastern Sichuan Basin.
万方数据
维普
