Very little helium is present in Earth's atmosphere. It is such a light element that Earth's gravity cannot hold it. When present at Earth's surface, unconfined helium immediately begins rising until it escapes the planet. That's why party balloons rise!
The helium that is produced commercially is obtained from the ground. Some natural gas fields have enough helium mingled with the gas that it can be extracted at an economical cost. A few fields in the United States contain over 7% helium by volume. Companies that drill for natural gas in these areas produce the natural gas, process it and remove the helium as a byproduct.
Most of the helium that is removed from natural gas is thought to form from radioactive decay of uranium and thorium in granitoid rocks of Earth's continental crust. As a very light gas, it is buoyant and seeks to move upward as soon as it forms.
https://geology.com/articles/helium/
Very little helium is present in Earth's atmosphere. It is such a light element that Earth's gravity cannot hold it. When present at Earth's surface, unconfined helium immediately begins rising until it escapes the planet. That's why party balloons rise!
The helium that is produced commercially is obtained from the ground. Some natural gas fields have enough helium mingled with the gas that it can be extracted at an economical cost. A few fields in the United States contain over 7% helium by volume. Companies that drill for natural gas in these areas produce the natural gas, process it and remove the helium as a byproduct.
Most of the helium that is removed from natural gas is thought to form from radioactive decay of uranium and thorium in granitoid rocks of Earth's continental crust. As a very light gas, it is buoyant and seeks to move upward as soon as it forms.