开江-梁平海槽的形成、发展和消亡过程对川东地区长兴组生物礁分布有着明显的控制作用,因而决定了生物礁气藏的类型、规模及其分布.通过露头、岩心观察和薄片鉴定手段,对台地边缘生物礁内部结构、发育特征的详细研究,表明台地边缘生物礁在海槽周缘的不同部位差别较大,按照生物礁发育规模,可将其分为台缘点礁、台缘丘礁和台缘堤礁,系统总结了这3种生物礁的生长演化阶段.其中台缘点礁主要发育于研究区环开江-梁平海槽的南端,发育于长-或长二到长三期,主要由障积礁组成,礁体发育时间短、发育规模最小,礁体发育最为简单,主要经历了3个演化阶段;台缘丘礁发育于研究区环开江-梁平海槽的中端-北端,发育于长二-长三期,大部分生物礁延续到了长三末期,礁体发育时间相对较长、发育规模相对较大,主要经历了5个演化阶段;台缘堤礁主要发育于鄂西海槽台地边缘或开江-梁平海槽最北端的川东北地区,礁体发育于长一时期或长二初期,一直延续到长三末期,礁体发育时间最长、规模最大,礁体最为复杂,经历了5个演化阶段.%The formation,development and consumption of Kaijiang-Liangping trough have obviously controlled the distribution of Changxing Formation reefs,and thus determined the types,sizes and distribution of the reef gas reservoirs.Through the detailed study of internal structures and their development,the authors found that the platform-edge reefs have very different sedimentary characteristics in different places near the trough,and could be divided into patch reefs,mound reefs and barrier reefs according to the development scales.The platformedge reefs and their evolutionary stages were summarized systematically.The patch reefs were mainly developed from Changxing 1st period or Changxing 2nd period to Changxing 3rd period on the southern side of Kaijiang-Liangping trough,characterized by the shortest formation time,the smallest scale,the most simple texture and three evolutionary stages.The mound reefs were mainly developed from Changxing 2nd to Changxing 3rd period on the middle to northern side of Kaijiang-Liangping trough,and their development could mostly last to the Changxing 3rd period,with the characteristics of larger scale,more complex texture relative to the patch reef,and five evolutionary stages.The barrier reefs were mainly developed from Changxing 1st to Changxing 2nd period at western Hubei trough or in east Sichuan area,and their development mostly lasted to Changxing 3rd period,with the characteristics of longest formation time,largest scale,most complex evolution and five evolutionary stages.
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