Where does the element helium come from on Earth?

Unlike hydrogen, helium on Earth is not abundant in the atmosphere because it escapes into space over time. Most commercially recovered helium is generated deep underground when alpha particles from uranium and thorium decay capture electrons and become helium atoms. That helium then migrates through rock and can become trapped in natural gas reservoirs. Major helium production has long come from gas fields in the United States, Qatar, and Algeria. Helium is valuable because it is used for cryogenics, MRI scanners, and other low-temperature technologies.