【摘要】 奥陶系碳酸盐岩是塔河油田的重要勘探领域之一,其储层类型主要为风化壳古岩溶作用下形成的岩溶缝洞系统。通过对塔河油田4区岩心、钻井、录井、测井以及地震等资料进行系统分析,发现研究区内风化壳古岩溶发育,作用标志明显:岩心中具有与原岩岩性不一致的沉积充填物;钻进中常有放空、井漏、井涌等现象发生;测井曲线上各物性参数大幅度变化;地震反射剖面见杂乱反射、弱反射、串珠状反射等特征。研究区风化壳古岩溶发育主要受可溶性岩石、不整合面、风化壳古地貌及古气候等因素控制,其中可溶性岩石和不整合面控制了古岩溶的空间分布,古地貌决定了风化壳古岩溶的深度、范围及强度,古气候决定了古岩溶的总体发育程度,在各因素共同作用下,形成了一系列岩溶缝洞系统。更多还原

【Abstract】 Ordovician carbonate is an important exploration area in Tahe oil field.The major reservoir type is karst seam and hole system in weathered crust formed by paleo-karstification.This paper analyzes core,well drilling,mud-logging,well-logging and seismic datas in the 4th block systematically.It is found that paleo-karst with obvious karst marks is well developed in karst seam and hole system in the study area.The paleo-karst marks including following features,such as infillings that different from the primary lithology in the core;the phenomena of lost circulation and kicking when drilling;great changes in physical property parameters in well-logging curves;irregular,weak or beaded reflection in seismic reflection profiling.The overall development degree of the paleo-karst is controlled mainly by soluble rock,unconformity plane,paleo landscape and climate.The spatial distribution of paleo-karst is controlled by soluble rock and unconformities;the weathering range,depth and intensity decided by paleo-landscape;and the paleo-climate decides the total extent of the paleo-karst.A lot of karst seam and hole systems are formed under the influence of these factors.更多还原