MrPickins
Diamond Member
Some regions have a higher helium component in the gas compared to others. That's why the U.S. is essentially the main supplier - Texas has the highest percentage of helium in the gas fields. Just the way the geography/ecology worked out in this case.
Purely a guess, but I'd wager there were/are more radioactive minerals in the helium rich areas.
(The helium is created by beta-decay)
