塔里木盆地奥陶系层间岩溶野外剖面及岩溶特征

古岩溶作用是塔里木盆地塔中、塔北地区海相碳酸盐岩储层形成的关键因素之一，塔中层间岩溶与塔北风化壳岩溶模式具有较大的差别。为进一步识别塔里木盆地层间岩溶发育模式，分析古岩溶发育特征。在前人研究的基础上，明确了奥陶系及上覆地层之间的地层缺失情况，通过野外剖面考察及室内岩心实验分析，考察了传统风化壳岩溶和层间岩溶野外剖面及典型特征。研究表明，层间岩溶具有明显的垂向分带性，自上而下分别为结核垆坶带（残积带）、风化裂隙带（渗流带）和溶蚀孔洞带（潜流带），各自形成的溶洞连续性较差；并发育多期旋回，组成数十米的层间岩溶发育带，为油气富集的有利区域。认为塔里木盆地层间岩溶型储层是多期次岩溶作用叠加改造后的结果。

Ordovician Interlayer Karst Field Profiles and Karst Characteristics in Tarim Basin

Paleokarstification is one of the key factors for the formation of marine carbonate reservoirs in Tazhong and north Tarim basin. The interlayer karstification in the middle Tarim basin is quite different from that in the weathering crust in the north Tarim basin. In order to further identify the development pattern of interlayer karst in Tarim basin and analyze the development characteristics of paleokarst. On the basis of previous studies, the stratigraphic loss between the ordovician and overlying strata is clarified. The field profile and typical characteristics of the traditional weathering crust karst and interlayer karst are investigated through field investigation and laboratory core experiment analysis. The results show that the interlayer karst has obvious vertical zoning, and the continuity of karst caves is poor from top to bottom, which are nodular loam zone (residual zone), weathered fracture zone (seepage zone) and dissolution cave zone (subsurface zone). It is also a multi⁃stage cycle, forming interlayer karst development zone of tens of meters, which is a favorable area for oil and gas enrichment. It is considered that the interlayer karstic reservoir in Tarim basin is the result of the superimposed transformation of multi stage karstification.