松辽盆地北部氦气分布特征及控制因素

Distribution characteristics and control factors of helium gas in northern Songliao basin

松辽盆地北部氦气藏主要分布于坳陷期至断陷期地层中,特别是坳陷期嫩江组至姚家组氦气含量平均值已达到0.172%,泉头组三段至四段氦气含量平均值为0.181%,登娄库组至火石岭组氦气含量平均值为0.234%。松辽盆地北部发育有4条北北东向深大断裂带和3条北北西向深大断裂带,这些深大断裂带是深部氦气向上运移的主要通道。松辽盆地北部青山口一段、嫩江组一段、二段泥质岩全区发育是良好的区域性盖层;青山口二、三段泥质岩在少数部分地区虽然有缺失,但因其厚度大也不失为好的区域性盖层。这4套区域性盖层为氦气成藏创造了良好条件。

The main distribution horizons of helium gas reservoirs in the northern Songliao basin are the depression formations and the faulted formations. The average helium gas value in Nenjiang-Yaojia formation was 0.172% and 0.181% in Quan4-quan3 formation. The helium average value is 0.234% in Denglouku- Huoshiling formation. There are 4 NNE deep faults and 3 NNE deep fractures in the northern Songliao basin, and the two fracture zones are the main channels for upward migration of deep helium. The No.1 - 2 Member of Nenjiang formation and the No. l Member of Qingshankou formation are good regional seal in northern Songliao basin. Although the No.2 - 3 Member of Qingshankou formation is not developed in a few areas, but its regional relatively large thickness is also a very good cover. The 4 sets of cap rocks benefit greatly for the helium gas accumulation.