三塘湖盆地石炭系火山岩油藏特征及主控因素

分析了三塘湖盆地石炭系哈尔加乌组（C₂h）及卡拉岗组（C₂k）油藏特征，认为有效烃源岩、有利岩相带和断裂带、邻近生油凹陷的古构造以及后期的改造作用，是三塘湖盆地石炭系火山岩油气成藏的主控因素。三塘湖盆地火山岩储层复杂，油气以纵向运移为主，侧向运移距离有限，有效烃源岩对油气分布具有非常明显的控制作用。继承性发育的古凸起、古构造，为多期运聚成藏提供了良好的构造背景。火山活动受深大断裂的控制，断层是油气运移的主要通道，深部位生成的油气沿断层或裂缝向隆起部位运移聚集成藏。溢流相上部亚相是有利火山岩储集相带，火山角砾岩储集性能和含油性最好，其次为玄武岩和安山岩。构造运动、风化淋滤产生的微裂缝有效地改善了储集空间，油气主要赋存于裂缝沟通的火山溶孔中。指出三塘湖盆地马朗凹陷、条湖凹陷、条山凸起、苇北凸起和南缘冲断带是有利的勘探领域，对该区的石炭系油气勘探具有重要意义。

Characteristics and controlling factors of volcanic reservoir of Carboniferous in Santanghu Basin

The reservoir characteristics of C2 h and C2 k of Carboniferous in Santanghu Basin are analyzed. It is considered that effective source rock, favorable facies zone and faulted zone, paleo tectonic near petroleum genetative depression and late reformation are the main controlling factors of reservoir accumulation of Carboniferous volcanic rocks in Santanghu Basin. The volcanic reservoir in Santanghu Basin is complex, and petroleum migrated mainly in vertical direction, with limited lateral migration. The effective source rock has a significant controlling effect on oil and gas distribution. Ancient uplift and paleo tectonic provide structural setting for hydrocarbon multi-stage migration and accumulation. Volcanic activity is controlled by deep fault, and fault is the main migration pathway. Oil and gas that generated from the deep fault migrated along fault and fracture to uplift and accumulated there. The upper subfacies of effusive facies is favorable zone for volcanic reservoir. Volcanic breccia has the best reservoir property and oiliness, followed by basalt and andesite. Micro-fracture that generated by tectonic movement and weathering and leaching effectively improved the reservoir space. Oil and gas mainly occurred in volcanic solution pore linked up by fracture. It is pointed out that Malang Sag, Tiaohu Sag, Tiaoshan Sag, Weibei uplift and the thrust belt in the southern margin of Santanghu Basin are the favorable exploration field.