塔东低凸起震旦系断陷台地沉积特征及发育模式

Sedimentary Characteristics and Evolution Models of the Sinian Rift Platform in the Low-Uplift,Eastern Tarim Basin

本文综合利用钻井岩心、地震剖面等资料,揭示了塔东低凸起震旦系沉积特征,并建立了沉积演化模式。研究认为,塔东低凸起震旦系白云岩可划分为三种沉积相类型,包括潮坪相、颗粒滩相和缓坡相。连井对比及地震剖面揭示,塔东低凸起震旦系具有楔状反射结构,反映了向北倾的断陷盆地沉积结构特征,整体上具有南高北低的沉积格局。本文结合区域构造背景,建立了由早期的向北缓倾单斜逐渐演变为断陷台地的沉积演化模式,认为断陷台地的主体发育在塔东1井至东探1井北部的斜坡部位。

By utilization of drilling cores and seismic data, this work revealed the sedimentary characteristics of Sinian in the low - uplift, eastern Tar- im basn and established its evolutionary model. The study suggested that three sedimentary facies were identified in the Sinian dolostones, including tidal flat, grain beach and ramp types. Well correlation and seismic sections showed that Sinian sedimentary sequences in this area have a wedge - shaped re- flective structure, indicating a northward dipping rift basin and overall pattern of high in south and low in north. An evolutionary model of the basin was constructed that shows a change from a northward gentle dipping monocline at the early stage into a rift platform, of which the primary portion is the slope from the well TD - 1 to the north of well DT - 1.