青藏特提斯板块构造与含油气盆地

TETHYAN PLATE STRUCTURES AND PETROLIFEROUS BASINS IN THE QINGHAI-TIBET PLATEAU

青藏特提斯是由5大地壳块体、3条板块缝合带经多期碰撞拼合而组成的复杂构造系统,由于新生代以来的强烈陆内汇聚作 用,现今主要表现为2个构造结点、3条汇聚边界和2大剪切带的构造运动学特征,边界的强烈汇聚与板内的强烈隆升、挤压剪切、 伸展剥离组成复杂而统一的动力学系统,具有厚壳和热壳特点。青藏特提斯含油气盆地可划分为海相复合型、海陆叠复合型和陆相 上叠型等3种基本类型,多含油气层系的复合与叠置、多期次构造运动的改造和岩浆热液活动的影响导致这些盆地具有地温场高、 地层压力低、储层致密和油气氧化界面深等显著特点。

The Tethys in the Qinghai-Tibet Plateau is a complex structural system which is formed by multiple collisions and coherences of five crustal blocks and three plate sutured belts. Due to strong inner-continental convergences since the Cenozoic, the Tethys in the Qinghai-Tibet Plateau presently has the structural kinematic features of two structural knots, three convergence boundaries and two great shear belts. The strong convergence of boundaries combined with inner-continental uplifting, compression-shearing and extension-stripping leaded to a complex and uniform kinematic system, characterized by a thick and hot crust. The petroliferous basins in the Qinghai-Tibet Plateau can be divided into three basic types as the marine compound basin, the superposed basin of marine and continent and the continental overlapped basin etc. These basins have some notable features such as high geothermal field, low formation pressure, tight reservoirs, deep oxidized hydrocarbon boundaries and so on, which were resulted from impressions brought about the re-combinations and overriding of multiple petroliferous strata, the reconstruction of multiple structural movements and the activities of hot magma.