塔里木盆地西北部氦气富集特征与成藏条件分析

氦气作为一种用途广泛的稀有非烃类气体，在一些油气藏天然气组分中不断被检测到，其中不少达到或超过了工业开采标准。从综合利用氦气资源考虑，对塔里木盆地西北部氦气富集特征和成藏条件进行了分析。通过石油钻井和测试资料分析表明，塔里木盆地雅克拉、沙西2号、巴什托和亚松迪等油气藏天然气组分中氦气含量较高，氦气作为天然气伴生物而富集成藏。其储集层位为下奥陶统、上石炭统、下二叠统和下白垩统，主要富集在构造圈闭高部位或油气藏顶部；其成因特征以壳源氦为主，有少量幔源氦的加入；二叠纪火山活动提供了丰富的氦源；深达基底的断层为深部氦气向上运移的通道，良好的封盖条件有利于氦气富集成藏与保存。

Analysis on Helium Enrichment Characteristics and Reservoir Forming Conditions in Northwest Tarim Basin

As a widely used non-hydrocarbon noble gas, helium has been frequently detected in natural gas out of oil and gas reservoir, many of which has reached or exceeded the industrial standard. Considering the comprehensive utilization of helium, we analyzed the helium enrichment characteristics and reservoir forming conditions in northwest Tarim basin. The drilling and test data showed that the content of helium in natural gas was higher in Yakela, Shaxi 2, Bashituo and Ysongdi, and helium accumulated as concomitant of natural gas. It was stored in Lower-Ordovician, Upper Carboniferous, Lower Permian and Lower Cretaceous, and mainly concentrated in the high part of structural traps and the top of reservoir. The helium was mainly from the crust, and a small amount of them was from the mantle. The volcanic activity in Lower Permian supplied a rich source of helium, and the deep faults provided a channel for helium to migrate upward. The good sealing condition was to the benefit of accumulation and preservation of helium.