塔里木盆地塔中地区志留系成藏控制因素

Control factors of Silurian system reservoir forming in Tazhong are a,Tarim Basin

在对塔里木盆地塔中地区构造背景和岩石学特征等研究的基础上,分析了塔中地区油气成藏的2个主要控制因素:一是具有有利的区域构造背景;二是发育中、下寒武统—下奥陶统的含泥或泥质泥晶白云岩及泥质泥晶灰岩和中、上奥陶统台缘斜坡灰泥岩、泥质泥晶灰岩2套烃源岩。综合分析表明,塔中地区有利的储集空间为石英含量超过65%的砂岩;该区分布志留系红泥岩段和下石炭统泥岩2个泥岩段等多套区域性盖层,并存在下红色砂泥岩段和柯坪塔格组中段暗色泥岩2套潜在盖层。

Based on the research of structure background, petrology character and so on in Tazhong area of Tarim Basin,two main control factors of the oil and gas reservoir forming were analyzed. The first is the favorable regional tectonic setting,and the second is the two sets of hydrocarbon source rock,one developed in muddy microcrystalline dolomite and micrite in the middle and lower Cambro - lower Ordovician, and the other developed in the middle and upper Ordovician calcilutite and micrite on the platform margin slope. Comprehensive analysis shows thatthe beneficial reservoir spaces in the Tazhong area are the sandstones with more than 65% of the quartz content {multiple sets of regional caprocks were developed, including red shale segment in Silurian and shale segment in lower Carboniferous system,and two sets of potential caprocks,including the lower red sand - shale segment and the dark shale segment in the middle of Kepingtage Formation in this area.