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大洋钻探184航次1148站位从南海当前的深海陆坡区取得了距今32.8Ma以来的沉积纪录,其中渐新世(32.8—23.8Ma)沉积包含了丰富的沟鞭藻化石,通过定量和定性结合的分析方法对沟鞭藻进行了研究。依据可指示地层时代关键种的最高产出层位和沟鞭藻组合特征,建立了1个组合带和2个亚带:Cleistosphaeridium diver-sispinosum组合带(A带)、Enneadocysta pectiniformis亚带(A-1亚带)和Cordosphaeridium gracile亚带(A-2亚带)。由Cl.diversispinosum、Co.gracile、Hystrichokolpoma pusillum和Homotryblium vallum的最高产出层位标定A带顶界,时代为渐新世;据Enneadocysta partridgei和E.pectiniformis最高产出层位划分出A-1亚带和A-2亚带;由E.partridgei,E.pectiniformis和Phthanoperidinium amoenum的生存时限可确定A-1亚带为早渐新世鲁培尔期(Rupelian);由Co.gracile,Distatodinium ellipticum,Wetzeliella articulata,W.gochtii和W.symmetrica等种的最高产出层位和分布时限可确定A-2亚带为晚渐新世夏特期(Chattian)。根据共存的沟鞭藻属种特征,新建立的化石带在不同程度上可与世界其他地区的同期沟鞭藻化石带或组合带进行对比,某些关键沟鞭藻种共存有助于确定化石带的年龄。
Ocean Drilling Flight 184, Station 1148, has made sedimentary records since 32.8Ma from the current deep-sea slope in the South China Sea. The Oligocene (32.8-23.8Ma) sediments contain abundant dinoflagellate fossils. Through quantitative and qualitative combination The method of analysis of dinoflagellate has been studied. Based on the combination of the highest output level of the key species and the dinoflagellate assemblage in the age of the stratigraphic age, one combination belt and two sub-belts were established: Cleistosphaeridium diver-sispinosum combination belt (A zone), Enneadocysta pectiniformis sub-zone (A- 1 sub-band) and Cordosphaeridium gracile sub-band (sub-band A-2). The A-1 sub-epoch was erased from the highest producing horizon of Cl.diversispinosum, Co.gracile, Hystrichokolpoma pusillum and Homotryblium vallum. The ages were Oligocene; A-1 sub-region was defined according to the highest output layer of Enneadocysta partridgei and E.pectiniformis A-2 and A-2 sub-bands; the A-1 sub-band was determined to be Early Oligocene Rupelian by the survival time of E.partridgei, E.pectiniformis and Phthanoperidinium amoenum; The highest output stratigraphy and distribution intervals of Wetzeliella articulata, W.gochtii and W.symmetrica can confirm that the A-2 sub-belt is late-Oligocene Chattian. Based on the coexisting features of the dinoflagellate species, the newly established fossil zones are, to varying degrees, comparable to the dinoflagellate fossils or assemblages in other parts of the world, and the coexistence of certain key dinoflagellates contributes to the identification of fossils The age of the band