高邮凹陷深凹带戴南组古生物特征及环境意义
袁静;肖运凤;董道涛;熊光勤;仇永峰
【期刊名称】《西南石油大学学报(自然科学版)》 【年(卷),期】2018(040)001
【摘要】Based on rock core and paleontology analyses data,combined with the sedimentary facies,the relationship between fossils,such as ostracods and charophytes,and the sedimentary environment of the first and second members of the fifth sub-member of the Dainan Formation in the Deep Sag of Gaoyou Sag were systematically analyzed.Seventy species of ostracods were identified,with the Cyprididae Baird section molecules being dominant,followed by Candonidae Kaufmann,and a small number of Limnocytheridae.The vertical variation in the fossil assemblage reflects the cyclic changes in the lake water during the Dainan Period,namely,brackish water→fresh water→brackish water→brackish water→fresh water.In addition,76 species
of
charophytes
were
identified,including
Grovesichara
chanqzhouensis,S tephanochara fortis,Obtusochara
lonqscoluminania,and Sphaerochara parvula.The first sub-member of the first member of the Dainan Formation is most prosperous,which manifests a quiet and brackish-fresh water environment during those periods.The vertical distribution and evolution of the ostracods and charophytes fossil combination has a close relationship with the