鄂尔多斯盆地靖边潜台及相邻区域在马五1-4时总体上为(内)陆棚盆缘坪亚环境.储层主要岩性为粉晶白云岩及含硬石膏结核和/或柱状晶的粉晶白云岩.地层在岩性上的分布差异是控制储层非均质发育的基础性因素,以含硬石膏结核和/或柱状晶的粉晶白云岩对研究区更具控制意义.其他主要控制因素还有地质背景、古岩溶成岩作用、构造裂隙及断层分布等,古地貌、储层有效厚度以及非储层发育程度等对储层非均质性也具一定影响.靖边潜台为目前天然气主产区,靠近研究区的西侧和东侧的储集性均较差,西侧地层剥蚀严重,东侧溶蚀作用过于强烈,储集性能均遭到严重破坏.

in the buried Jingbian Buried Platform and its periphery area of Ordos Basin, the sedimentary environment of Middle Ordovician Majiagou 51-4 Sub-member reservoir is generally the inner shelf basin-marginal flat facies. The Majiagou 51-4 reservoir consists of silt-sized crystalline dolostone. Difference of lithology is the basic factor that controls heterogeneity of the reservoir. Silt-sized crystalline dolostone with anhydrite-nodules and/or columnar crystallines plays a predominant role in controlling heterogeneity in this area. Other controlling factors are geologic background, palaeokarst diagenesis, tectonic fissures, fault distribution，etc. In addition, palaeogeomorphology, effective thickness of reservoir and development of non-reservior are also effective. The main gas-producing zone is in Jingbian Platform but the reservoir did not well-developed or along the west part of the platform where strata are severely eroded and the east part rock is heavily dissolved.