Argon-36 from Neutron Capture on Chlorine in Nature
نویسنده
چکیده
Argon analysis on samples of sodalite from Dungannon, Ontario reveals an excess of 36Ar from neutron capture on 35C1 and excess 40Ar from the decay of 40K. These results indicate an average production rate of 5.6 X 102 atoms of 3®C1 per year per gram of chlorine over the age of the mineral. 3 .9X 108 yrs. The surface residence time of chlorine-rich rocks may be determined from the amounts of 36Ar which accumulate during the time period of exposure to cosmic rays.
منابع مشابه
Cosmogenic chlorine-36 production rates in terrestrial rocks
Chlorine-36 is produced in rocks exposed to cosmic rays at the earth surface through thermal neutron activation of 35C1, spallation of 39K and 't°Ca, and slow negative muon capture by 4°Ca. We have measured the 36C1 content of 14C-dated glacial boulders from the White Mountains in eastern California and in a 14C-dated basalt flow from Utah. Effective, time-integrated production parameters were ...
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