鄂尔多斯盆地华庆地区长9油藏富集特征及潜力区预测  

Enrichment Characteristics and Potential Area Prediction of Chang9 Reservoir in Huaqing Area of Ordos Basin

作　　者：杨浩 阳波[3] 石伟[3] 林丽[3] 方燕[3] 朱玉双[1,2] Yang Hao;Yang Bo;Shi Wei;Lin Li;Fang Yan;Zhu Yushuang(State Key Laboratory of Continental Dynamics,Xi′an,Shaanxi 710069,China;Northwestern University,Xi′an,Shaanxi 710069,China;PetroChina Changqing Oilfield Company,Qingcheng,Gansu 745100,China)

机构地区：[1]大陆动力学国家重点实验室,陕西西安710069 [2]西北大学,陕西西安710069 [3]中国石油长庆油田分公司,甘肃庆城745100

出　　处：《特种油气藏》2023年第2期78-85,共8页Special Oil & Gas Reservoirs

基　　金：国家自然科学基金“高热与超压背景的成岩响应及流体活动对储层成岩-孔隙演化的影响”(41972129)。

摘　　要：针对鄂尔多斯盆地华庆地区长9油藏的分布规律以及富集特征不够明确,限制了研究区勘探开发的现状,通过对长9油藏的构造特征、岩石学特征、储集孔隙空间、砂体发育特征等因素综合对比剖析,根据长7油藏过剩压力分布特征以及油气成藏配置探讨了研究区长9油藏富集规律及潜力区预测。结果表明:长9油藏局部低幅度构造及裂缝发育为油气运聚提供了有利条件;长9油藏发育长石岩屑砂岩及岩屑砂岩;填隙物发育绿泥石、浊沸石、铁方解石,其次为水云母、硅质等;长9油藏储集孔隙主要为粒间孔、长石溶孔,为特低孔特低渗-低孔低渗油藏;长9油藏储层砂体的连通性受到浅水三角洲前缘环境的控制;韵律、隔夹层的发育及其他储层非均质性差异造成研究区油气富集的差异;长9油藏油源来自长7烃源岩,受到长7内部过剩压力的作用下选择性充注成藏,导致油气在区域上分布不均;结合油藏地质研究以及过剩压力恢复分布特征,认为元521井区可作为下一步勘探有利区。研究结果对华庆地区长9油藏的深入勘探具有一定指导意义。In response to unclear understanding of distribution pattern and enrichment characteristics of Chang9 Reservoir in Huaqing Area,Ordos Basin,which restricts the exploration and development of the study area,after a comprehensive comparison and analysis of the tectonic characteristics,petrological characteristics,reservoir pore space and sand body development characteristics of Chang9 Reservoir,the enrichment rule and potential area of Chang9 Reservoir in the study area were discussed according to the characteristics of excess pressure distribution and hydrocarbon accumulation configuration of Chang7 Reservoir.The results show that the local low-amplitude structure and fracture development in Chang9 Reservoir are favorable for hydrocarbon migration and accumulation.Feldspathic lithic sandstone and lithic sandstone are developed in Chang9 Reservoir.The interstitial materials are chlorite,turbidite and ferrocalcite,followed by hydromica and silicalite.The reservoir pores of Chang9 Reservoir are mainly intergranular pores and feldspar dissolved pores,leading to extremely low porosity and permeability,so Chang9 Reservoir is of low porosity and permeability.The connectivity of sand bodies in Chang9 Reservoir is controlled by the environment of shallow water delta front.The differences of rhythm,interbed development and heterogeneity of other reservoirs result in the differences in hydrocarbon enrichment in the study area.The oil source of Chang9 Reservoir originates from the source rock of Chang7 Member.The source rocks are selectively filled into the reservoir under the action of the internal excess pressure of Chang7 Member,resulting in the uneven distribution of hydrocarbons in the area.According to the reservoir geological study and the characteristics of excess pressure distribution and recovery,Block Yuan521 is considered as a favorable area for the next exploration.There is much guiding significance of the study results for the deep exploration of the Chang9 Reservoir in Huaqing Area.

关 键 词：低渗透砂岩 富集规律 沉积砂体 华庆地区 长9油藏 鄂尔多斯盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探]