伦坡拉第三纪盆地的形成机理和石油地质特征

位于班-怒大断裂中的赞-兹断层右行走滑拉分,是伦坡拉盆地形成的动力学机制.盆地的石油地质特征表现为：①现今构造格局具南北分带、东西分块的特点;②牛堡组不仅厚度大,而且分布广,自下而上三段的粒度和颜色还具粗-细-粗和红-黑-红的特点,而丁青湖组不仅粒度细,而且颜色深,厚度小,分布局限;③源岩颜色深、粒度细、厚度大、分布广、有机质类型好、成熟度中等、转化率高;④储集砂体厚度大、分布广,且孔、渗条件好;⑤油气显示类型多、分布广,原油密度较大,粘度较低,高蜡低硫,后生变化强烈

THE FORMING MECHANISM AND PETROLEUM GEOLOGY OF TERTIARY LUNPOLA BASIN,TIBET

The right-handed strike-strike slip pull apart of Zan-Zi fault in the Ban-Nu main fault zone is the dynamic mechanism for the formation of Lunpola Basin. Features of petroleum geology in the Basin are as follows:(1)The tectonic nie frarnewark today is canstituted by south-north divided belts,east west divided blacks. (2)The Niubaa formation is thick and widely distributed and the grain size and color from bottom to top are coares-fine-coarse and red-black-red. The Dingyin ghu formation is a series of fine-grained blank and elastic rocks,limited in distribution.(3)The source racks are black,fine-grained and thick,extensive in distributian. The organic matter is in good type.matured and high in transformation ratio. (4)The reservoir sand bodies are extensively distributed,and goad in porosity and permeability. (5)Various types of ail and gas shows are widely distributed. The crude oil is heavy in specific gravity,low in viscosity,high in wax and low in sulfur.and with intensive changes after its generation.