中国新疆塔里木盆地上奥陶统良里塔格组的钙藻化石

CALCAREOUS ALGAE FROM THE UPPER ORDOVICIAN LIANGLITAGE FORMATION IN THE TARIM BASIN,XINJIANG,CHINA

钙藻是可以发生生物钙化作用形成钙质"骨骼"的分属多个门类的藻类的俗称。钙藻最早出现于寒武纪,奥陶纪发生第一次辐射演化。本文系统讨论了绿藻门绒枝藻目(Dasycladales)、羽藻目钙扇藻科(Udoteaceae)的科和属级分类标准和红藻门珊瑚藻科、管孔藻科(Solenoporaceae)属级分类标准及其中各属分类中存在的问题。塔里木盆地晚奥陶世在塔中—巴楚台地和塔北台地发育了一套礁滩相良里塔格组碳酸盐岩,其中含有丰富的钙藻化石。本文系统描述了来自塔里木盆地塔中、巴楚、塔北地区取心井上奥陶统良里塔格组岩层中的钙藻化石11个属15个种。包括绿藻门绒枝藻目西莱特藻科(Seletonellaceae)的Dasyporella,Kazakhstanelia,Vermiporella,Aphroporella,Arthroporella,绿藻门的羽藻目Bryopsidales(siphonales)的钙扇藻科的Dimor phosiphon,Palaeo porella,红藻门珊瑚藻目(Corallinales)的管孔藻科的Solenopora,Parachaetetes及Corallinales incertus familiae的Petro-phyton,以及分类位置不明的Monili porella。其中绒枝藻Ajakmalajsoria被视作Kazakhstanelia的同义名。

Calcareous algae are the algae which can precipitate carbonate to form carbonate skeletons.Calcareous algae first appear in the Cambrian,and had its first major evolutionary radiation in the Ordovician.The primary calcareous algae are green algae and red algae.This paper discusses the classification criterion of families and genera of the Dasycladales and Udoteaceae of Bryopsidales in Chlorophyta and problems existing in the system classification of Solenoporaceae in Rhodophyta.The marginal carbonate facies of the Upper Ordovician Lianglitage Formation include two carbonate platforms in the Tarim Basin,the Central—Bachu Tarim and Northern Tarim,representing the bank and reef facies with abundant calcareous algae fossils.This paper describes 15 species belonging to 11 genera of calcareous algae from the Upper Ordovician Lianglitage Formation of the wells in the Central—Bachu Tarim and Northern Tarim platforms.The Dasycladales components described herein include Dasyporella,Kazakhstanelia,Vermiporella,Aphroporella,Arthroporella,and the Udoteaceae include Dimorphosiphon and Palaeoporella.Ajakmalajsoria is regarded as a synonym of Kazakhstanelia.The Solenoporaceae described here include Solenopora,Parachaetetes,and also Petrophyton which is Corallinales incertae familiae.The genus Moniliporella has a uncertain position in the red algae or the green algae.