华南板块古生代生物礁及其古地理控制因素  

PALEOZOIC REEFS AND THEIR PALEOGEOLOGICAL CONTROLS IN SOUTH CHINA BLOCK

作　　者：王建坡[1] 李越[2] 程龙[1] 曾雄伟[1] 王冠[2] 

机构地区：[1]中国地质调查局武汉地质调查中心,武汉430205 [2]中国科学院南京地质古生物研究所,南京210008

出　　处：《古生物学报》2014年第1期121-131,共11页Acta Palaeontologica Sinica

基　　金：国家自然科学基金(41072002);中国地质调查局项目(1212011120148);"早古生代重大生物事件及其背景机制"研究项目(41221001)联合资助

摘　　要：华南板块在古生代处于中、低纬度,碳酸盐岩类型多样并形成不同时空背景下的多种生物礁建造,生物礁发展序列基本吻合于全球古生代生物礁的宏演化趋势,寒武纪生物群和古生代动物群演化过程中重要造礁生物门类的起源、辐射、灭绝与复苏事件是塑造礁群落基本生态结构的历史因素。寒武纪早期的古杯-藻礁和继之的微生物礁生长区域相当局限;早—中奥陶世的苔藓虫礁、藻礁以及瓶筐石-硬海绵礁群落分异明显;晚奥陶世珊瑚-层孔虫礁以及藻丘建造见于浙赣局限台地及台缘带,而扬子区志留纪兰多维列世生物礁的生长频繁受陆源碎屑岩覆盖;中泥盆世的珊瑚-层孔虫-藻礁群落结构相对稳定,晚泥盆世法门期—密西西比亚纪的微生物礁、苔藓虫-珊瑚礁、宾夕法尼亚亚纪—早二叠世的苔藓虫-海绵-藻礁、中—晚二叠世的珊瑚-苔藓虫-海绵-藻礁可诠释为与生物灭绝事件相关的幕式群落演替。区域构造活动导致的岩相分异和海平面变化显著制约生物礁的时空分布。中—晚奥陶世的偏深水环境、志留纪兰多维列世—早泥盆世早期扬子区整体抬升的古地理格局造成适宜于生物礁生长海域的缩减;泥盆纪较长的温室期促进了生物礁发展,而宾夕法尼亚亚纪—早二叠世偏凉的海洋水体对生物礁的规模影响力度明显。从华南板块古生界整体的视角看,海相碳酸盐岩具有量值优势,海水在时间尺度和空间展布上多维持较高的清澈度,陆源碎屑岩沉积在特定的时间段可视为生物礁生长的主控因素;海平面变化因其幅度有限可在单剖面或区域上控制生物礁群落的纵横迁移,碳酸盐岩沉积区多见基底沉降与沉积补偿速率基本均衡,具备不同规模的浅海相沉积空间,因此水深变化并非起到决定性作用。特定时段碳酸盐岩台地海水的盐度异常可造成大规模白云岩沉积可排除生�South China Block was mostly located within middle--low latitude belt during the Paleozoic time. Reef types with temporal and spatial differentiations are abundant in distribution from diverse carbonate facies. The community structures basically matched the global macroevolutionary patterns especially the essential changeover from the Cambrian Fauna and Paleozoic Fauna. The origin, radiation, extinction and recovery events are enhanced as the mechanisms and historically configured profiles of reef successions. Archaeocyaths-microbial reefs of the Early Cambrian and onward microbial reefs extended limitedly. Bryozo- anal, microbial and Calathium-lithistid sponge reefs diversified in ecological components at the Early--Middle Ordovician. Coral-stromatoporoidalgal and microbial reefs of the Late Ordovician reefs occurred from the limited platform as well as its margin of the Zhe-Gan border region. Growth of the Llandovery reef in the Yangtze Platform was frequently covered by terrigenous debris. Ecological associations of the reefs were relatively stable with duration from the Middle Devonian to early Late Devonian. Microbial, bryozoan-coral reefs from the Famennian, Late Devonian to Mississip- pian, bryozoan-sponge-algal reefs of the Pennsylvanian to the Early Permian, coral-bryozoan-sponge- algal reefs of the Middle--Late Permian show dramatic replacement of the reef-building biota trig- gered by mass extinction events. Regional tectonic movements and sea level fluctuations significantly restricted temporal and spatial distributions of the reefs. High sea-level of the Middle--Late Ordovician and uplifting of the whole Yangtze region from the Llandovery to the early Early Devonian shrankhabitation realms of the reefs palaeogeographical- ly. Long-term greenhouse of the Devonian promo- ted the development of the reef-building. Howev- er, cool marine water condition constrained the reef magnitude from the Pennsylvanian to the Ear- ly Permian. Carbonates are dominated in value throughout the Palaeozoic sequences of the

关 键 词：生物礁类型 古地理 古生代 华南 

分 类 号：Q911[天文地球—古生物学与地层学] P534.4[生物学—古生物学]