Natural production of radionuclides in geological formations

Determination of underground production of radionuclides important in 'dating' groundwater and in problems related to underground disposal of high-level radioactive waste disposal is discussed. For estimation of natural production of radionuclides the neutron energy spectrum in the rock must be calculated based on the rock chemical composition and its physical parameters. Details on several interesting radionuclides produced in spontaneous fission of uranium and in reactions with underground neutrons are given.