Reef Types and Sedimentation Characteristics of Changxing Formation in Manyue-Honghua Section of Kaixian,Northeastern Sichuan Basin  

作　　者：吴立群 焦养泉 荣辉 王瑞 李荣 

机构地区：[1]Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education,China University of Geosciences [2]Faculty of Earth Resources,China University of Geosciences [3]College of Geosciences,China University of Petroleum [4]Department of Earth and Atmospheric Sciences,University of Alberta

出　　处：《Journal of Earth Science》2012年第4期490-505,共16页地球科学学刊（英文版）

基　　金：supported by the SINOPEC Forward Looking Projects of China (Nos. YPH08114 and 2009026324)

摘　　要：In Changxing （长兴） stage, Manyue （满月）-Honghua （红花） Section of Kaixian （开县）, northeastern Sichuan （四川） Province was located in the platform-margin slope, which was the advantage area of reef-shoal depositional system developing. The strata of Changxing Formation are continuously exposed on both Honghua Section and Manyue Section. Four and two depositional cycles ean be identified in Honghua Section and Manyue Section, respectively. They are all platform-margin reef-shoal deposits. Their lithologic associations have obvious sequence, which is as follows： micrite bioclast limestone, bafflestone, bindstone, framestone, and bioclast limestone, in order from below. The paleontological assemblages are controlled by water depth and genetic facies. Six paleontological as- semblages can be identified in Honghua Section and Manyue Section; they are coral-calcareous algaecalcareous sponge assemblage, calcareous sponge-calcareous algae assemblage, calcareous spongecalcareous algae-coral-bryozoan assemblage, calcareous sponge-calcareous algae-hydra assemblage, calcareous sponge-calcareous algae-hydra-bryozoan assemblage, and calcareous sponge-calcareous algae-hydra-bryozoan-coral assemblage. The study of lithologic associations and paleontological assemblages indicates that the water body shallowed upward in both the growth cycle of a single reef and the higher-grade depositional cycle. According to the water depth types of reef （bioherm） developing, three different reef-shoal depositional systems can be identified in study area： deep-water-type bioherm, transitional-type reef （bioherm）, and more shallow-water-type reef.In Changxing （长兴） stage, Manyue （满月）-Honghua （红花） Section of Kaixian （开县）, northeastern Sichuan （四川） Province was located in the platform-margin slope, which was the advantage area of reef-shoal depositional system developing. The strata of Changxing Formation are continuously exposed on both Honghua Section and Manyue Section. Four and two depositional cycles ean be identified in Honghua Section and Manyue Section, respectively. They are all platform-margin reef-shoal deposits. Their lithologic associations have obvious sequence, which is as follows： micrite bioclast limestone, bafflestone, bindstone, framestone, and bioclast limestone, in order from below. The paleontological assemblages are controlled by water depth and genetic facies. Six paleontological as- semblages can be identified in Honghua Section and Manyue Section; they are coral-calcareous algaecalcareous sponge assemblage, calcareous sponge-calcareous algae assemblage, calcareous spongecalcareous algae-coral-bryozoan assemblage, calcareous sponge-calcareous algae-hydra assemblage, calcareous sponge-calcareous algae-hydra-bryozoan assemblage, and calcareous sponge-calcareous algae-hydra-bryozoan-coral assemblage. The study of lithologic associations and paleontological assemblages indicates that the water body shallowed upward in both the growth cycle of a single reef and the higher-grade depositional cycle. According to the water depth types of reef （bioherm） developing, three different reef-shoal depositional systems can be identified in study area： deep-water-type bioherm, transitional-type reef （bioherm）, and more shallow-water-type reef.

关 键 词：northeastern Sichuan Manyue-Honghua Section Changxing Formation reef. 

分 类 号：P618.13[天文地球—矿床学]