鄂尔多斯盆地西北部地区天然气成藏地质特征与勘探潜力  

Geological Characteristics and Exploration Potential of Natural Gas Reservoir in Northwest Region of Ordos Basin

作　　者：何自新[1] 付金华[1] 孙六一[1] 

机构地区：[1]中国石油长庆油田公司,陕西省西安市710021

出　　处：《中国石油勘探》2002年第1期56-66,共11页China Petroleum Exploration

摘　　要：鄂尔多斯盆地是一个多层系含油气盆地,天然气勘探近年来在盆地中北部上、下古生界取得一系列重大发现,探明了苏里格特大型气田和靖边大气田,为鄂尔多斯盆地成为中国天然气工业的重要基地奠定了基础。盆地西北部即天环北段和西椽冲断构造带北部具有与盆地中北部相似的成藏条件,天然气资源丰富,其上古生界为一套海陆过渡相的碎屑岩系;下部石炭系太原组及二叠系山西组为煤糸烃源岩,生烃能力强。二叠系山西组和上下石盒子组发育了一套河流—三角洲相沉积,砂体发育,储层物性好;下古生界发育海相碳酸盐岩沉积,岩溶储层厚,物性好,可接受上、下古生界两套烃源供给,气源充足;奥陶系风化壳上覆铝土质岩类,封盖条件好,有利于形成大型地层、岩性圈闭。上、下古生界生储盖配套,形成了三套有利的成藏组合及多种类型的成藏圈闭,具有良好的勘探前景。Ordos basin is an oil and gas basin with multiple stratum series. Natural gas exploration has led to a series of major discoveries in the middle northern part of the basin from Upper Paleozoic to Lower Paleozoic in the recent years. Giant gas fields have been proven, such as Sulige Super-giant gas field and Jingbian gas field, enabling Ordos basin to become the important base for China's natural gas industry. The northwestern part of the basin, namely the northern Tianhuan section and the western peripheral thrust faulted structural belt, has the same reservoir conditions as the middle northern part of the basin. This area is rich in natural gas with Upper Paleozoic being a set of clastic series of transitional facies and Lower Paleozoic being coal hydrocarbon source rock of carboniferous Taiyuan formation and Permian Shanxi formation with strong source capability. In Permian Shanxi formation and Upper and Lower Shihezi formations developed a set of fluvial-delta sediment with good development of sand body and good reservoir physical propertie. In Lower Paleozoic developed carbonate rock sediment of marine facies with thick karst reservoir and good physical properties, which can accept hydrocarbon supply both from Upper Paleozoic and Lower Paleozoic with an adequate gas source. The Ordovician weathering crust has good sealing and covering conditions of aluminum rock on the top, favorable for formation of large-scale stratum and lithologic trap. The sourcereservoir-caprock assemblage is good for both Upper Paleozoic and Lower Paleozoic, forming three sets of favorable reservoir assemblages and various types of reservoir traps. Therefore, this area has a promising prospect for exploration.

关 键 词：鄂尔多斯盆地 天然气 成藏条件 地质特征 油气勘探潜力 

分 类 号：P618.13[天文地球—矿床学] TE13[天文地球—地质学]