摘要
大牛地气田位于鄂尔多斯盆地东北部,总体上属于致密砂岩气藏,该区石炭系本溪组发育铝土质泥岩,传统上认为其是下古生界风化壳的盖层;但研究后却发现本溪组铝土质泥岩不同于一般的泥岩或页岩,前者具有更好的孔隙网络,同时也有较好的气测显示,可以作为潜在储层。为此,利用烷烃气碳同位素比较法,首先判别了该区铝土质泥岩储层的气源,发现其天然气来源于石炭—二叠系煤成气、下古生界碳酸盐岩自生气和铝土质泥岩内部泥页岩自生气所组成的混源气,而以石炭—二叠系煤成气为主;在此基础上,利用常规测井和特殊方法测井资料总结出了铝土质泥岩储层的测井响应特征,进而分析、评价了形成储层的原因及储层的品质;最后对该区本溪组铝土质泥岩储层的厚度进行了平面分布预测。结果表明：该类储层普遍发育,连续性较好,但其厚度不均匀（介于2.0~21.6m）,总体上由北西向南东方向逐渐变厚。该研究成果为大牛地气田铝土质泥岩储层的勘探开发提供了技术支持。
The Daniudi Gasfield,located in the northeast of the Ordos Basin,is characterized by tight sandstone reservoirs.The bauxitic mudstones are developed in the carboniferous Benxi Formation in the Daniudi Gasfield,which is traditionally considered as the caprock of the Lower Palaeozoic weathered crust.However,this study shows that bauxitic mudstones in the Benxi Formation have better pore network and fairly good gas logging show,which is different from regular mudstones or shales,and can be promising hydrocarbon reservoirs.For this reason,the alkane carbon isotope comparison method was used to firstly discriminate that there is source-mixed natural gas inside the bauxitic mudstones,which is composed of Carboniferous-Permian coal-derived gas,Lower Palaeozoic carbonate authigenous gas and mud shale authigenous gas,and is mainly dominated by the Carboniferous-Permian coal-derived gas.Then,conventional and special log data were used to find out the log response characteristics of bauxitic mudstone reservoirs,and the reservoir origin and quality were further analyzed and evaluated.Finally,horizontal distribution of Benxi Formation bauxitic mudstone reservoir thickness was predicted.The results show that this type of reservoir is universally developed,with good continuity,and with uneven thickness（2.0- 21.6 m） gradually increasing from northwest to southeast in general.This conclusion provides technical support for the exploration and development of bauxitic mudstone reservoirs in the Daniudi Gasfield.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2015年第5期24-30,共7页
Natural Gas Industry
基金
中国石油化工集团科技攻关项目"低对比度致密砂岩油气测井响应机理与评价方法"(编号:P13111)
中国石化青年科技创新基金"致密砂岩裂缝参数测井定量评价模型研究"(编号:P14136)
关键词
鄂尔多斯盆地
大牛地气田
石炭纪
铝土质泥岩
储集层
风化壳
混源气
微孔隙
碳同位素比较法
测井特征
Ordos Basin
Daniudi Gasfield
Carboniferous
Bauxitic mudstone
Reservoir stratum
Weathered crust
Source mixed natural gas
Micropore
Carbon isotope comparison method
Logging characteristics
