【摘要】 通过使用普里兹湾的多道地震剖面的地质解释资料,对其地层结构和沉积特征进行了研究,并对其构造、沉积演化过程和油气资源潜力进行了分析.结果表明:研究区地层可以划分为5个沉积单元,包括前寒武纪(性质不确定)的变质岩基底(PS.5),晚二叠世-早三叠世期间和白垩纪期间的两期裂谷期沉积(PS.4及PS.3),晚始新世-中新世期间被冰川改造的被动大陆边缘沉积(PS.2)及上新世以来的冰川沉积(PS.1),其间均被不整合面所分隔.两期裂谷事件的沉积中心位于普里兹湾中部,并受断层控制.新生代以来沉积逐渐向着陆架外缘进积加厚,并被冰川作用所改造,沉积环境也由中生代的陆相转变为新生代的滨海相、冰川相.普里兹湾的白垩世和中新统有较高的有机碳含量,而其间的沉积类型为冰川沉积,有机碳含量很低.后者可能是由于冰川的底侵作用,使得深部有机碳含量较高的沉积在上部重新沉积的结果,普里兹湾断陷盆地区的PS.3以及陆架外缘以及陆坡深水区的PS.2上部(中新统)可能是油气的潜力生成区.更多还原

【Abstract】 Based on the interpretation of multi-channel seismic profiles across the Prydz Bay,East Antarctica,the stratigraphic sequences and sedimentary characteristics in this area are worked out in this study.In addition,the tectono-sedimentary evolution and hydrocarbon potential are explored.Five stratigraphic units are determined(PS.1,PS.2,PS.3,PS.4and PS.5from top down)in this study.Unit PS.5is composed of Precambrian metamophic basement rocks.Unit PS.4and PS.3are rift fillings deposited during two extensional events,with the age of Late Permian to Early Triassic,and Cretaceous respectively.Unit PS.2is composed of seaward dipping passive-margin sediments between Late Eocene to Miocene,and was affected by Neogene Glacial events.PS.1is glacial deposit since Pliocene.All these units are separated by unconformities.The sedimentary center during two rifting periods,containing nonmarine continental strata,is located in the center of Prydy Bay,and the sediments are controlled by normal faulting.Since Cenozoic the sequences prograded to the continental shelf-break,depositing in marine and glacial environments.High TOC of terrestrial origin have been discovered in part of the Cretaceous and Miocene with mature organic matter,of which the latter may be related to glacial erosion that recycled sediments.We suggest the Cretaceous deposits in the rifted basin and the Miocene deposits in out shelf and abyssal slope area are potential layers for hydrocarbon exploration.更多还原