By means of sequence stratigraphy theory and based on the analysis of lithostratigraphy, logging stratigraphy and seismic stratigraphy, eo-cene-miocene carbonera formation in middle Llanos basin is divided into four 3rd-order sequences. All the four sequences are composed of the trans-gressive system tract deposits inner shelf and pro-delta and the high-stand system tract mainly deposits delta front, the low-stand system tract doesn't present. The integral exhibits four series of marine invasion to dereliction depositional cycle. The tectonic movement and sea level change are the main controlling factors of the sequences of Carbonera formation. According to the analysis of sequence evolution and petroleum geology conditions, the delta subsea distributed channel developed in high-stand system tract are favorable explorative targets for high quality reservoirs.%以层序地层学理论为指导,通过对岩石地层、测井地层、地震地层等资料的综合分析,将Llanos盆地中部始—中新统Carbonera组划分为4个三级层序.4个层序均由海侵体系域和高位体系域组成,缺失低位体系域.海侵体系域发育内陆棚～前三角洲泥质沉积,高位体系域以发育三角洲前缘砂质沉积为主,整体上显示为四套从海进到海退的沉积旋回.构造运动和海平面升降是控制Llanos盆地中部Carbonera组层序形成与发育的主要因素.层序演化及石油地质条件分析表明,高位体系域中发育的三角洲前缘水下分流河道,是寻找优质储层的有利目标.
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