We present results of the determination of 36C1 (Tu2 =3.0-105 a) in rock samples produced in situ by cosmic rays and natural radioactivities. These experiments were designed to determine the feasibility of using 36C1 for studying erosion processes in calcium rich minerals like limestone or dolomite. The 36C1/C1 ratios in the samples have been determined with accelerator mass spectrometry (AMS) at the Munich accelerator laboratory. A first application is the investigation of the erosion in the last million years in Allchar (Yugoslavia) for the feasibility study of the geochemical 2~ solar neutrino experiment.PACS: 91.00; 23.40; 28.20.Fc long-living cosmic ray produced radioisotopes [5,6]. The life time of the radioisotope determines the range of time in which the mean erosion can be deduced. Suitable radioisotopes are 26A1 (T1/2 = 7.2.105 a), 36C1 (T1/2 = 3.0.105 a) and 53Mn (T1/2 : 3.7-106 a). Accelerator mass spectrome try allows the measurement of low concentrations of radioisotopes, down to relative abundances of 10-15 [7]. The required minerals should have low concentrations of stable A1, C1 and Mn, respectively, so that the ratio of concentrations [radioisotope]/[element] is larger than the detection limit. Another important fact is to avoid atmospheric produced contaminations of 26A1, 36C1 and 53Mn induced by rain water.

No abstract