歧北凹陷下第三系深层沉积相及储层特征研究

Characteristics of Eogene deep sedimentary facies and reservoir in the north of Qikou sag

歧北凹陷下第三系深层主要指埋藏深度大于3500m的下第三系沙一下段地层，本文根据钻井、测井资料，在前人研究成果的基础上，从取芯井入手，建立相应的岩——电模式，以此来确定本区深层的沉积相类型及其分布特征，并在此基础上分析储层的特征及其控制因素。研究表明：储层的沉积相、成岩作用和异常压力直接影响了深层储层的储集物性，它们是预测有利储层的主要依据，其中本区最有利沉积相带是重力流主水道；有利的压力系数在1．2～1．6之间1次生孔隙最发育的埋深为3400～3600m和3700～4000m。

The deep zone of Eogene system in the north Qikou sag is the Es13 zone that buried depth is more than 3500 meter, according to drilling and logging data and the study result of predecessor, result about the rock-electric log mode from core data, and determine the deep zone sedimentary facies and its distributing characteristics, and analysis reservoir characteristics and its control factors. The result indicates： the sedimentary facies and diagenesis and abnormal pressure directly affect the physics property of the deep zone reservoir, it is the evidence that predict favorable reservoir. The best favorable sedimentary facies is the main aqueduct of mass flow; the favorable pressure factor is between 1.2 and 1.6; the buried depth that the best favorable secondary pore occurs is between 3400m and 3600m, and between 3700m and 4000m.