【摘要】 按照由整体到局部的思路,利用已钻井的有孔虫、钙质超微等古生物资料,结合岩性及古地貌,对琼东南盆地渐新统崖城组沉积环境进行综合研究。研究结果表明:琼东南盆地崖城组沉积时期,北部坳陷早期为陆相环境,中晚期古生物开始间歇性出现,丰度与分异度普遍不高,为泻湖—潮坪环境;而中央坳陷从崖城组早期古生物便呈间歇—较连续性出现,丰度与分异度较高,为局限滨海—浅海环境,据此推断位于中央坳陷的长昌凹陷崖城组时期为局限滨海—浅海环境。其中,扇三角洲、三角洲、海岸平原及滨海沼泽围绕凹陷周缘分布,斜坡部位发育大面积滨海沉积,凹陷中央为浅海。根据平面沉积充填特征、典型地震剖面,以及前人的研究成果,综合分析认为长昌凹陷崖城组属典型的地堑式沉积发育模式。更多还原

【Abstract】 From the whole to local,based on the foraminifera and calcareous nannofossil data of the wells,lithology and tectonic paleogeomorphology,comprehensive analysis on sedimentary environment of Yacheng Formation in Qiongdongnan basin has been done.Thestudy results indicate that during the sedimentation period of Yacheng Formation,the northern part of this depression is continental at the early stage,in the middle and later stage,the fossil appeared discontinuously,being lagoon-tidal flat facies;the fossil appeared more continuously in the central depression in Qiongdongnan basin,the abundance and diversity are much higher,being deposited under restricted shallow-sea environment.Therefore,it is concluded that the environment of Changchang depression in this unit is restricted shallow-sea.Fan delta,delta,coastal plain and coastal marsh distribute around depression,large area of coast deposit are well developed in the slope,and shallow sea are well developed in the center of depression.According to the planar sediment filling characteristics and typical seismic profiles,combined with the previous study results,it is believed that Yacheng Formation in Changchang depression is typical graben sedimentation and developemt model.更多还原