Patent ID: 8283173

Claim:
A process utilizing natural carbon-13 isotope for identification of early breakthrough of injection water in oil wells, the process comprising the steps of: (a) periodic collection of water samples from different sources, (b) chemical treatment of the water samples, as collected in the step (a), in the field itself, to precipitate dissolved inorganic carbon species, (c) collection of precipitates as obtained in the step (b) and treatment with an acid, for extraction of CO 2 , (d) trapping the CO 2 as extracted in the step (c) by coolants, (e) measuring the δ 13 C content from CO 2 as collected in the step (d), and (f) comparison of spatio-temporal variation of δ 13 C content as obtained in the step (e) of different samples collected to identify the wells showing early breakthrough of injection water.