三塘湖盆地构造演化与油气聚集

三塘湖盆地处于西伯利亚板块南缘,早石炭世晚期,盆地褶皱基底形成；晚石炭世早期,总体处于碰撞期后伸展构造环境；晚石炭世晚期,洋壳消亡,断陷收缩与整体抬升,形成剥蚀不整合.早二叠世,进入陆内前陆盆地演化阶段；中二叠世,盆地进入推覆体前缘前陆盆地发育期；晚二叠世,构造褶皱回返,前陆盆地消失；三叠纪晚期至侏罗纪中期,进入统一坳...

Structure evolution and petroleum accumulation of Santanghu Basin

Santanghu Basin is in the southern rim of the Siberia plate.In the late stage of Early Carboniferous，formed folding base； In the early stage of Late Carboniferous，this basin undergone a extension period after collision activity； In the late stage of Late Carboniferous，Its evolution was composed by the following tectonic activity：ocean crust extinction，fault depression shrinkage and basin uplifting，formed erosion unconformity.In the Early Permian，began foreland basin evolution stage； the middle Permian was a nappe front foreland basin developmental stage.In late Early Permian，this foreland basin disappeared； From Late Triassic to Middle Jurassic，it was a uniform depression； In the Late Jurassic Early Cretaceous，it was formed the tectonic framework of this basin.Santanghu Basin was divided into three structural belts：east northern thrust nappe uplift，central depression and west southern thrust nappe belt.There are two types structural styles：basement involved and capping slided.In the Tiaohu Malang sag，it developed three effective hydrocarbon source formations(Upper Carboniferous，Middle Permian and Jurassic Shuixigou Formation).These hydrocarbon source have a characteristic of two periods hydrocarbon generating and accumulating； formed three independent hydrocarbon accumulation systems，shown as a character of “late period and near source，self generation and self preservation.There are three types of hydrocarbon accumulation：accumulated in the north eastern depression uplift and paleo uplift，in the north western thrust fault belt，in the unconformity.The petroleum source of Santanghu Basin was up to 7×108～9×108t.It has a low exploration degree.There are four exploration potentials：shallow Jurassic litho stratigraphic reservoir surrounding Malang Tiaohu depression，Carboniferous volcanic weathering crust reservoir in the northern uplift，Permian dolomite and Carboniferous volcanic reservoir in the southern thrust nappe belt.