Serpulids and their paleoecology of the Paleogene Kalatar Formation in southwest Tarim Basin of China  

作　　者：YANG HaiJun SHEN JianWei ZHANG LiJuan LI Meng HUANG ZhiBin WANG Yue 

机构地区：[1]Key Laboratory of Marginal Sea Geology of CAS,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China [2]Exploration and Development Research Institute,Tarim Oilfield Company,Petroleum Company Limited,Korla 841000,China

出　　处：《Science China Earth Sciences》2012年第7期1087-1100,共14页中国科学（地球科学英文版）

基　　金：supported by National Natural Science Foundation of China(Grant Nos. 40872078,40976030);Knowledge Innovation Program of South China Sea Institute of Oceanology (Grant No. LYQY200806);the Research Project of Tarim Oilfield Company (Grant No. 41009080051)

摘　　要：Polychaete serpulids are globally distributed tubeworms mostly in marine environments from Late Triassic to modem time. These calcareous tubeworms could be rock-forming, reef-building, or a principal fouling organism in harbor and bays. Car- bonates of the Paleogene Kalatar Formation in southwest Tarim Basin yield abundant serpulid fossils, which, together with oyster fossils, constitute the characteristic fossil assemblage of the Kalatar Formation. Other common fossils include bivalves, gastropods, ostracods, echinoderms, and bryozoans. Lithologies that yielded serpulid fossils are characterized by micritic bio- clastic limestone, sandy limestone, and shelly limestone, indicating a semi-restricted to open shallow marine environment with medium to low water energy. The research data about serpulids and their fossil materials from China are relatively rare. Based on the studies of tbssils taxonomy, community palaeoecology, and fossil taphonomy, this paper analyzed and studied the types, occurrence, distribution, and morphological characteristics of serpulids and their palaeoecological features in the Kalatar For- mation. Two serpulid community compositions were recognized in the Kalatar Formation, including a rock-forming Ditrupa community and a cluster-growth Propomatoceros community. The Ditrupa community was distributed in coastal environment of the west Kunlun piedmont, lived on sandy hard substrates with little mud, and rarely occurred in lagoon and tidal settings. The Propomatoceros community occurred in offshore middle carbonate ramp in the piedmont of the south Tianshan Moun- tains and in offshore shelf in the piedmont of the west Kunlun Mountains. According to the analysis on the host-rock litholo- gies, preservation and symbionts, it is inferred that serpulids in the Kalatar Formation grew on the oyster shell or other hard substrate, and they did not form reefs or bioherms.Polychaete serpulids are globally distributed tubeworms mostly in marine environments from Late Triassic to modern time.These calcareous tubeworms could be rock-forming,reef-building,or a principal fouling organism in harbor and bays.Carbonates of the Paleogene Kalatar Formation in southwest Tarim Basin yield abundant serpulid fossils,which,together with oyster fossils,constitute the characteristic fossil assemblage of the Kalatar Formation.Other common fossils include bivalves,gastropods,ostracods,echinoderms,and bryozoans.Lithologies that yielded serpulid fossils are characterized by micritic bioclastic limestone,sandy limestone,and shelly limestone,indicating a semi-restricted to open shallow marine environment with medium to low water energy.The research data about serpulids and their fossil materials from China are relatively rare.Based on the studies of fossils taxonomy,community palaeoecology,and fossil taphonomy,this paper analyzed and studied the types,occurrence,distribution,and morphological characteristics of serpulids and their palaeoecological features in the Kalatar Formation.Two serpulid community compositions were recognized in the Kalatar Formation,including a rock-forming Ditrupa community and a cluster-growth Propomatoceros community.The Ditrupa community was distributed in coastal environment of the west Kunlun piedmont,lived on sandy hard substrates with little mud,and rarely occurred in lagoon and tidal settings.The Propomatoceros community occurred in offshore middle carbonate ramp in the piedmont of the south Tianshan Mountains and in offshore shelf in the piedmont of the west Kunlun Mountains.According to the analysis on the host-rock lithologies,preservation and symbionts,it is inferred that serpulids in the Kalatar Formation grew on the oyster shell or other hard substrate,and they did not form reefs or bioherms.

关 键 词：serpulids PALAEOECOLOGY Kalatar Formation PALEOGENE southwest Tarim Basin 

分 类 号：P542.3[天文地球—构造地质学] Q914.81[天文地球—地质学]