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通过对南极半岛鲍威尔盆地及邻区多道地震数据、重磁数据及测井数据的综合解译,对其地层结构和沉积特征进行了研究,并对其新生代构造、沉积演化过程以及主控因素进行了分析.对地震剖面的解释共划分出4个层序界面,5个构造沉积单元.研究结果表明鲍威尔盆地是一个典型的弧后盆地,始新世以来西侧太平洋板块向南极半岛之下持续的俯冲,以及东侧新生代以来威德尔海向斯科舍地区俯冲带的后撤,导致南极半岛发生近东西向的伸展作用,南奥克尼微地块与南极半岛裂离,并最终在早渐新世末期-早中新世期间发生海底扩张作用.南奥克尼微地块一侧的东部陆缘与南极半岛一侧的西部陆缘表现为被动陆缘特征,为共轭陆缘.其南北两侧陆缘则表现为走滑-拉张特征.对研究区沉积过程的控制因素进行研究,包括构造活动和沉积物源,海平面变化,以及冰川作用.其中南极半岛新生代冰川作用的影响因素显示了高纬度区边缘海盆地独特的沉积特征.
Through the comprehensive interpretation of multi-channel seismic data, gravity and magnetic data and well logging data in the Powell Basin and its adjacent areas in the Antarctic Peninsula, the stratigraphic and sedimentary characteristics of these systems were studied. The Cenozoic tectonic evolution, The analysis of the seismic profile shows that there are four sequence boundaries and five tectonic sedimentary units.The results show that the Powell Basin is a typical backarc basin.The western Pacific plate to the Antarctic Peninsula since the Eocene The continued subduction and the retreat of the Weddell Sea subduction zone to the Scotia region since the Cenozoic on the east led to the near east-west extension of the Antarctic Peninsula and the separation of the South Orkney Micro-Territory from the Antarctic Peninsula Eventually led to the expansion of the seafloor during the late Oligocene-Early Miocene.The eastern continental margin on the South Orkney Microfossil side and the western continental margin on the Antarctic peninsula side are characterized by passive continental margins as conjugate The continental margins on both the north and south sides are characterized by strike-slip-pull characteristics.The controlling factors of the sedimentary processes in the study area are studied, including tectonic activities, source of sediments, sea-level change and glaciation. The influencing factors of the Peninsula Cenozoic glaciation show the unique sedimentary characteristics of the marginal sea basin in the high latitudes.