What is the primary source responsible for the atmospheric abundance of Argon?

Answer

Slow, steady byproduct of radioactive decay of Potassium-40 (K-40) within the Earth’s crust.

Atmospheric argon is primarily generated through the decay of Potassium-40 into Argon-40 over geological time, making its abundance a reflection of the planet's internal nuclear history.

What is the primary source responsible for the atmospheric abundance of Argon?
atmosphereGasesabundance