塔里木盆地塔中隆起构造演化与油气关系

笔者结合塔里木盆地形成的构造背景对塔中隆起的主要构造演化过程进行了研究,并具体分析了各构造演化阶段与志留系油气的关系。研究表明,塔中隆起源于早古生代拉张背景下的正断层,寒武-奥陶纪为其烃源岩形成的重要时期;早奥陶世末-晚奥陶世末的构造反转是塔中隆起的主要形成期,同时也为志留系的形成及复合圈闭提供了古地理背景;泥盆纪末塔中鼻状隆起基本定型,古油藏遭受破坏,形成了沥青砂岩;早二叠世晚期的构造变形使古油藏遭受进一步的破坏;二叠纪后构造变动主要以调节为主。伴随整个构造的演化,志留系的油气聚集也是分期次、不同规模的进行。

Tectonic evolution and its bearings to the oil and gas with in the central Tarim uplift of the Tarim Basin,Xinjiang

The central Tarim uplift resulted from a normal fault during the Early Palaeozoic extension. The Cambrian and Ordovician periods are important phases for the formation of source rocks. The tectonic inversion gave rise to the formation of the uplift during the latest Early Ordovician to the latest Late Ordovician. During the latest Devonian,the central Tarim uplift came into being,the pre-existing oil pools were subjected to the failure,and the asphaltic sandstones were well developed. The late Early Permian magmatic activities led not only to the further destruction of the early geological structures and oil pools,but also to the formation of new structures favourable for the accumulation of newly-generated oil and gas. The middle Caledonian and early Hercynian orogenies played an important part in the accumulation and preservation of the Silurian strata in which abundant oil pools are hosted.