This is a big warning sign of an impending quake!
Helium-3 is a very rare gas that is commonly bound up in silt on the moon but only found deep under the Earth's mantle. If you've detected that gas coming from a fault it means your fissure is tapping the molten layer down there! The only thing keeping it from coming up is prayers and God's grace at that stage. The pressure is lower the higher you get so that's an optimum location for a really big release or subduction to occur. We mean biblical level quake, West Coast into the ocean, that sort of tremor.
… but there is bound to be some bad news in this discovery as well.