全球泥盆纪生物礁演化及其影响因素  

EVOLUTION OF DEVONIAN REEFS AND ITS INFLUENCING FACTORS

作　　者：黄家园 梁昆 王玉珏 郄文昆[1] HUANG Jia-yuan;LIANG Kun;WANG Yu-jue;QIE Wen-kun(Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008;University of Science and Technology of China, Hefei 230026)

机构地区：[1]中国科学院南京地质古生物研究所和生物演化与环境卓越创新中心,资源地层学与古地理学重点实验室,江苏南京210008 [2]中国科学技术大学,安徽合肥230026

出　　处：《地层学杂志》2019年第2期198-209,共12页Journal of Stratigraphy

基　　金：中国科学院战略性先导科技专项项目(XDB26000000;XDB18000000);国家自然科学基金项目(41772004);科技部基础性专项项目(2013FY111000);现代古生物学和地层学国家重点实验室资助共同资助

摘　　要：泥盆纪是地史时期海洋生物迅速演化的时期之一,以发育显生宙以来地球上最大规模生物礁生态系统及其彻底崩溃为重要特征。泥盆纪的生物礁经历了吉维特-弗拉期和法门期的繁盛,造礁生物分别以珊瑚-层孔虫和菌藻类为主导;在吉维特中晚期、弗拉-法门期(F/F)之交和泥盆纪-石炭纪(D/C)之交,则遭受多次生物灭绝事件的打击,随后在石炭纪的杜内早-中期生物礁基本消失,而后生动物礁直到13 Myr之后(维宪期)才再次出现。通过最新的地球化学资料研究发现,中泥盆世海水表层温度适宜、大陆风化程度较低。因此,全球后生动物礁规模空前,异常繁盛;而晚泥盆世海水表层温度及大陆风化程度较高,导致法门期后生动物礁衰落,而菌藻类生物礁繁盛。通过灭绝事件的详细研究表明,Taghanic事件中海平面的快速上升、温度的急剧升高造成珊瑚和层孔虫消失,后生动物礁数量大幅减少;Kellwasser事件中的温度突变、全球性海平面升降以及缺氧等因素则引发了后生动物礁彻底崩溃;而Hangenberg事件中短暂复苏的后生动物礁受温度降低和海平面下降的影响而最终消失。因此,在众多影响泥盆纪生物礁发育的因素中,全球性的温度和海平面变化占据主导地位。Devonian is generally portrayed as a time of rapid evolution of marine organisms, characterized by the development of the largest Phanerozoic reef ecosystem and its complete collapse. Devonian reefs thrived during the Givetian-Frasnian and Famennian, and they were dominated by coral-stromatoporoid and microbe-algae, respectively. Meanwhile, extinction events at the late middle-Givetian, the Frasnian-Famennian boundary(F/F) and the Devonian-Carboniferous boundary(D/C) exerted major impacts on Devonian reefs. As a result, the earliest Carboniferous was devoid of reefs, and metazoan reefs did not recover until 13 million years later. Recent geochemical researches indicate that during the Middle Devonian, the sea surface temperature in low-middle latitude regions was suitable and the continental weathering rate was repressed, leading to the unprecedented metazoan reef ecosystem in Earth history. With the enhancement of sea surface temperature and continental weathering rate during the Late Devonian, metazoan reefs started to decline in the late Frasnian,and bacterial and algal reefs flourished in the Famennian. In the Taghanic event, the rapid rise of sea level and temperature resulted in the extinction of corals and stromatoporoid and a significant reduction of metazoan reefs. In the Kellwasser event, the sudden change of temperature, the fluctuation of sea level and local anoxia caused the complete collapse of metazoan reefs. During the latest Devonian, the stepwise recovery of metazoan reefs was terminated by the Hangenberg event, due to the drop of temperature and global sea level. Among all the factors that affect Devonian reefs, global temperature and sea level changes are most important.

关 键 词：泥盆纪 生物礁 温度变化 海平面波动 生物灭绝事件 

分 类 号：P534.44[天文地球—古生物学与地层学]