Carbon-14 is produced in the stratosphere by nuclear reactions of atmospheric nitrogen with thermal neutrons produced naturally by cosmic rays (with the highest production rate 10 to 13 miles above Earth’s poles), as well as by atmospheric nuclear weapons testing in the 1950s and ’60.
The bomb effect refers to the addition of “artificial” radiocarbon to the atmosphere as a result of nuclear weapons testing.
Pac Man Impact Site Hypothesis (-17°, -107°) Pangea didn't happen 