东濮凹陷早第三纪生物记录中的地质事件

本文综述了介形类、沟鞭藻等各门类化石居群的变化特征,认为沙三和沙一段沉积期为东濮凹陷早第三纪生物群繁盛阶段.化石演变呈陆相广布居群与地方居群交替出现的特征,其演变包含孔店组至沙四下亚段、沙四下亚段至沙四上亚段、沙一段至东营组等的渐变,并伴有洪水事件;沙四上亚段至沙三段、沙三段至沙二段、沙二段至沙一段等的突变,伴有水质变咸、变淡及风暴等地质事件.从化石组合序列、沉积相区及沉积物源等论述了沉积间断事件.

GEOLOGICAL EVENTS IN BIOLOGICAL RECORDS IN EOGENE IN DONGPU SAG

The evolution features of Ostracode fauna,Dinoflagellate flora etc.are summarized in this paper.There comes that the Sha3 and Sha1 are prosperity summits in early Tertiary biocoenosium in Dongpu sag.The terrestrial and local biocoenosium fossils emerged alternately.The evolution of biocoenosis contains the gradual changes from Ek to early Sha4,early Sha4 to late Sha4,Sha1 to Ed with flood event,and the sudden changes from late Sha4 to Sha3,Sha3 to Sha2,Sha2 to Sha1 accompanied by the events of alternations of the salinity change of the paleolacustrine water and occurence of tempests.The author also ex-pounds an event of the sedimentary gap on the basis of fossil assemblage sequence,sedimentary facies and sedimentary source charateristics.