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塔里木盆地寒武系沉积前的古构造格局对于寒武纪早期快速海侵形成的优质烃源岩的分布有显著控制作用。结合钻井和露头资料研究了塔里木盆地南华纪—震旦纪的早期演化过程及寒武系沉积前的古构造格局,进而探讨了玉尔吐斯组和西山布拉克组源岩的分布特征。研究认为塔里木盆地在南华纪—震旦纪期间存在多个先后发育的、大小不等的、彼此孤立的裂陷中心,一般都经历了快速的填平补齐,晚震旦世沉积的白云岩段在全区基本可以对比,震旦纪末期的柯坪运动导致盆内大部分地区抬升,造成区域上构造地貌的差异。寒武系沉积前盆地内存在EW向古隆起带,环绕古隆起带的盆地内大部分地区可能为地势平坦的滨浅海碳酸盐台地,古地貌特征表现为从中央隆起带向南北两侧平缓降低,下寒武统优质烃源岩的发育与寒武纪早期快速海侵过程中的热水活动—上升洋流—缺氧事件有关,古构造格局暗示其在北部坳陷一带应该具有稳定广泛的分布。
The Paleo-tectonic setting before Cambrian deposition in the Tarim Basin has significant control over the distribution of high-quality source rocks formed by rapid transgression of the Cambrian. Based on the drilling and outcrop data, the early evolution of South China Sea-Sinian in the Tarim Basin and the palaeotectonic structure before Cambrian sedimentation were studied. Then the distribution characteristics of source rocks in the Yü Tu Tuo Group and Xilang Braque Group were discussed. The study suggests that there are several well-developed and isolated rift centers in the Tarim Basin during the Nanhua-Sinian period, which generally experienced rapid filling and dolostone deposition in the late Sinian period Sections can be basically compared in the whole area. The Keping movement at the end of the Sinian caused the uplift in most parts of the basin, resulting in differences in tectonic topography in the area. There are EW paleo-uplift belts in Cambrian pre-sedimentary basins, and most of the areas surrounding the paleo-uplift belts may be flat coastal shallow marine carbonate terraces. The paleogeomorphology is characterized by gentle relief from the central uplift to both north and south Lower Cambrian high-quality source rock development is related to the hot water activity-rising ocean current-anoxic event in the early Cambrian rapid transgression process. The palaeoconformational pattern implies that it should have a stable and extensive distribution in the northern depression distributed.