利川花椒坪长兴组生物礁岩层序地层研究

Sequence Stratigraphy Analysis and Reservoir Evaluation of Reef of Changxing Formation in Huajiaoping of Lichuan

摘要: 利川花椒坪位于川东碳酸盐岩台地与鄂西海槽之间的台地边缘相带，晚二叠世长兴期该区水体逐渐由深变浅，发育了一套规模巨大的加积–近积型台地边缘生物礁沉积。通过野外露头剖面精细地质写实研究，对花椒坪生物礁岩层序地层与储层进行了深入分析。研究表明利川花椒坪生物礁礁体主要在Sq1高位体系域和Sq2海侵体系域，内部由4个准层序组成。随着相对海平面不断下降，水动力条件逐渐增强，利川花椒坪经历了生物礁奠基、初期繁盛、最大繁盛和生物礁衰亡等四个演化阶段。

Abstract: Huajiaoping of Lichuan is located in platform margin facies between carbonate platform facies in eastern Sichuan and Western Hubei Trough. In the study area, the water gradually changed from the deep to shallow in the stage of Changxing Formation of Late Permian, and developed a huge scale of platform margin reef deposition in aggradation- progradation. Through the multidisciplinary analysis of measured profiles, the authors made an in-depth analysis on the Huajiaoping reef sequence stratigraphy and reservoir. The study demonstrated that the body of reef in the Huajiaoping of Lichuan was located in HST of sequence 1 and TST of sequence 2 of Changxing Formation, and internally consti- tuted by the four parasequence sets. As the relative sea level fell gradually and hydrodynamic force improved progres- sively, the reef in the Huajiaoping had experienced four stages of evolution, including the foundation stage, the initial flourishing stage, the prosperous stage, and the organic reef declining stage.