子长油田肖家河区延长组沉积相特征研究

The study on the characteristic of sedimentary facies of the Xiaojiahe area in Zichang oilfield

通过野外剖面和井下岩心观察描述并结合测井资料,对子长油田肖家河区主力油层组长4+5和长6沉积相展布特征及演化规律进行了系统的研究,结果表明:该区沉积构造特征多样,主力油层组发育两套三角洲沉积亚相,其中长61~长4+51为三角洲平原亚相,长64~长62为三角洲前缘亚相,在此基础之上又识别出6种沉积微相,自下而上沉积微相平面显示出沉积环境在演化过程中既有继承性又存在差异性。分流河道和水下分流河道为砂体的有利控制相带,从而进一步影响着储层特征及油气富集规律。

Based on the observation of field and core as well as the logging data, the characteristics of sedimentary facies of main producing reservoir, Chang 4+5 and Chang 6, in the Xiaojiahe area of Zichang oilfield were systematically studied. The results show that the geological features in study area are diverse. Two sets of sedimentary subfacies are well recognized in this area, of which, the subfacies of Chang 61~Chang 4+51 are delta plain,the subfacies of Chang 64~Chang 62 are the delta front. Moreover, six kinds of sedimentary microfacies could be recognized. Form bottom to up, the sedimentary environment has both inheritance and difference in the evolution process. The distribution of sand body is controlled by the sedimentary facies and influences hydrocarbon accumulation rules.