随着塔河油田主体区潜山风化壳岩溶勘探开发的不断深入,斜坡区的内幕岩溶储集层越来越受到人们的关注,断裂对岩溶储集层的形成和分布具有重要控制作用。综合利用岩心、薄片、测井、钻井和地震资料,在储集层类型基础上,分析了断裂对岩溶储集层发育的控制作用及断控岩溶储集层分布规律,探讨了断控岩溶储集层的形成机制和演化特征。断裂和岩溶储集层发育规模、期次存在着一定的耦合关系,多期次继承发育的Ⅱ级和Ⅲ-1级断裂对岩溶储集层控制作用明显。平面上岩溶储集层沿断裂呈条带状分布,垂向上储集层分布在距奥陶系一间房组顶面0~50和100 m~150 m范围内。深部岩溶储集层形成作用主要有大气淡水溶蚀作用、TSR(硫酸盐热化学还原反应)、热液溶蚀作用和混合溶蚀作用4种类型,海西早期是断控岩溶储集层发育的主要时期。%The internal karst reservoirs in the slope area of Tahe oilfield ,Tarim Basin have attracted more and more atten-tion as further exploration and development were carried out in the weathering crust karst reservoirs in the buried hills of the main blocks in the field .It is generally agreed that faults control the formation and distribution of karst reservoirs . Based on reservoir classification ,the paper analyzed control effect of faults upon karst reservoirs and their distribution and discussed forming mechanism and evolving characteristics of the reservoirs through study of core , thin sections , logging and drilling as well as seismic data .A coupling relationship between extent and phases of development of faults and karst reservoirs was revealed during the analyses .Multi-phased and inherited faults of gradeⅡandⅢ-1 seemed to have a more prominent controlling effect upon the karst reservoirs .Horizontally , the reservoirs distributed as belts along faults; and vertically ,they were observed to occur within intervals 0-50 m or 100-150 m below the top of the Ordovician Yijian-fang Formation .The paper also suggested that these reservoirs were formed mainly by meteoric water dissolution , TSR ( Thermochemical Sulfate Reduction ) ,hydrothermal dissolution ,and hybrid dissolution .The Early Hercynian was believed to be the main stage for the development of the fault-controlled karst reservoirs in the field .
展开▼