Spallogenic 14C in High-Altitude Rocks and in Antarctic Meteorites

14 C in high-altitude rocks and in Antarctic meteorites of long terrestrial age has been found at levels consistent with in-situ production by cosmic rays. Levels of 0.2–0.59 dpm/kg (or 1.0–2.6 × 10 6 14 C/g) are found in high-altitude samples ranging from 3300 to 5460m. Similar values are observed in Antarctic meteorites that have been dated by 81 Kr by Freundel, Schultz & Reedy (1986) as over 100 kyr old.