Method for judging helium supply of basement granite to helium-rich natural gas reservoir

The invention discloses a method for judging helium supply of basement granite to a helium-rich natural gas reservoir, which is characterized by comprising the following steps of: 1, selecting a core sample in a specified area, detecting and analyzing rare gas of the core sample through desorption gas and gas in the core sample, detecting the helium content, judging whether the helium content meets the standard or not, and if yes, judging whether the helium content meets the standard or not; and if yes, performing the next step. And 2, detecting the relationship between the U and Th contents in the granite core of the drilling base and the ground granite sample in the area and the helium content released after the rock is crushed, and obtaining that helium with higher content can be generated by granite with high U and Th contents in the same year. According to the method for judging helium supply of the substrate granite to the helium-rich natural gas reservoir, a gas source comparison method is adopted, hel