地层倾角测井在沉积微相研究中的应用

Application of dip logging in the study of sedimentary micro-facies

宋子齐 冯玉成 唐长久 李伟峰 王 艳

西安石油大学， 陕西 西安 710065 河南油田分公司魏岗油矿，河南 南阳 473132

Xi’an Shiyou University, Xi’an, 710065, China Weigang Oilfield, Henan Oilfield Company, SINOPEC, Nanyang 473132 , China

针对雁木西油田白垩系低阻油层受沉积相带及其断裂、构造和岩性等多种因素控制影响，测井信息应用难度增大的特点，采用地层倾角测井资料确定古水流方向、砂体延伸、层理构造和微相特征。利用倾角方位频率矢量统计，确定出白垩系K1s3、K1s2、K1s1目的层段古水流及其相应河道砂体延伸方向为北北东20°。利用层理构造倾角模式分析，确定出白垩系K1s3、K1s2、K1s1期分别发育楔状交错层理、波状斜层理、波状交错层理和水平层理，结合岩心、井径、自然伽马和微侧向电阻率曲线特征，分别阐明白垩系K1s3、K1s2到K1s1期水动力能量由较高到较低变化，形成了扇三角洲前缘扇中的水下辫状河道到扇端的浅水河道有利微相砂体发育带，由南南西向北北东方向展布，控制研究区最为有利的油气储集砂体分布。

To aim at the characteristics that low resistivity reservoirs of Yanmuxi oilfield are influeced by the sedimentary faces, fault, structure and lithology and the application of logging data becomes more difficult, dip logging data is adopted to determine paleocurrent direction, sand body extension, stratification structure and microfacies characteristics. By the Statistics of dip orientation, we identified the direction of paleocurrent of K_1s3, K_1s2 and K1s1 and their palaeo-channel sedimentary sand orientation was NNE 20°. By using the analysis of stratification structure model, cross bedding pattern, current bedding and flat bedding had
been developed in the Cretaceous of all the above layers. Combined with core, CAL, GR, and MLL Characteristic curve, the flow rate changing of the palaeo-channel is made clear, which is from higher to lower. Beneficial sedimentary sand area of microfacies from under water braided channel in delta front to shallow channel on the distal end has been generated. The orientation of sedimentary sand is in south-southwest to north-northeast, which controls the distribution of the best reservoir sand in this area.