乌尔逊凹陷油气运移方向研究

Migration direction of oil and gas in Wuerxun Depression

刘志文

Liu Zhiwen

大庆油田有限责任公司勘探开发研究院，黑龙江 大庆 163712

(Research Institute of Exploration and Development, Daqing Oilfield Co. Ltd. , CNPC, Daqing 163712, China).

乌尔逊凹陷的油气分布严格受生油凹陷的限制，主要分布在油源区内或其附近、油源区及其周边的断裂构造带上。凹陷内的油气藏主要分布在乌尔逊凹陷北部生烃洼槽边缘，苏仁诺尔走滑断裂带两侧，有的位于有效生烃灶内，有的位于有效生烃灶边缘；乌尔逊凹陷南部油气发现主要是在巴彦塔拉构造转换带地区。综合利用含氮化合物的多种指标，可以确定油气运移方向，研究油气运移通道，指出断裂和不整合面是凹陷内油气运移的主要通道，两者配合使油气呈现阶梯状运移。

The hydrocarbon distribution in Wuerxun Depression is strictly controlled by the source sag and the hydrocarbon is mainly distributed in the source sag or near the source sag. Furthermore,the oil and gas are also found near the tectonic belt as Surenluoer and Bayantala. The reservoirs in the north of Wuerxun Depression are on the border of source sag and near the both sides of Surenluoer strike slip belt. Some reservoirs are located in the corner of valid source rocks and some are located in the border of valid
source rocks. Discovery of hydrocarbon in the south of Wurenxun Depression is mainly in the Bayantala structural transfer zone. Pyrrolic nitrogen compounds are used as tracers for determining oil migration direction and researching the path of oil migration. This paper points out that fault and unconformity are the main paths for migration. The migration is in stepped shape under the control of unconformity and fault.