Cosmic ray contributions to dose rates for luminescence and ESR dating: Large depths and long-term time variations

In previous work, we have discussed the way in which the contribution of cosmic rays to the dose rates for TL/ESR dating depends on altitude, latitude and depth below ground level. The present paper extends the discussion to greater depths. Long-term changes in the geomagnetic field and the galactic cosmic ray intensity could affect the dose rate. The effects are shown to be small over the past 500 ka in most circumstances.