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通过对南海北部琼东南盆地渐新世—上新世3个钻井剖面412个沟鞭藻样品的系统分析,发现了较丰富的沟鞭藻化石。根据沟鞭藻化石丰度、分异度变化以及特征性的环境指示种,对琼东南盆地渐新世至上新世的沉积环境进行了详细研究。认为研究区从早渐新世早期海水开始入侵,至早渐新世晚期海侵范围进一步扩大,一直持续到晚渐新世;早中新世沟鞭藻化石数量和种类明显出现低谷,发生了一次较为明显的海退;中中新世至晚中新世,沟鞭藻化石较丰富,丰度和分异度增加,海水明显比早中新世沉积时期加深;早上新世早期,指示海侵的化石属种较丰富,反映了温暖浅海的沉积环境;早上新世晚期,指示一种开阔的海洋环境,水体较深;晚上新世早期,沟鞭藻化石属种面貌反映了热带浅海环境,但水体可能比早上新世晚期沉积时要浅;晚上新世晚期,指示海侵的沟鞭藻化石属种达到最繁盛时期,海侵范围进一步扩大。
Through systematic analysis of 412 samples of Daphniphyllum from three Oligocene-Pliocene sections in the Qiongdongnan Basin in the northern South China Sea, abundant dinoflagellate fossils have been found. According to the fossil abundance, diversity and diversity of the dinoflagellates, the depositional environment of Oligocene to Pliocene in the Qiongdongnan Basin was studied in detail. It is considered that the study area began to invade from the seawaters in the early Oligocenocene and further expanded to the late Oligocene up to the Early Oligocenocene. The number and species of Fagaceous algae in Early Miocene downturn obviously occurred, A more obvious regression. From Middle Miocene to late Miocene, the dinoflagellate fossils are richer in abundance and diversity, and the seawater is significantly deeper than the Early Miocene depositional period. In the early morning and early Pliocene, Invaded fossil species are abundant, reflecting the depositional environment of warm shallow sea. In the late period of Early Pliocene, it indicates an open marine environment with deep water body. In the early period of the Late Pliocene, the genera of the genus Dinoflagellates reflect the tropical shallow sea environment , But the water body may be shallower than that deposited in the late Pleistocene. In the late stage of Late Pleistocene, the genus Ditchinae which indicated the transgression was reached the most prosperous period, and the scope of transgression was further enlarged.