Abstract: ~(113)In~m-CHARCOAL AS A NEW RADIOTRACER FOR DETERMINING THE WATER INTAKE PROFILES IN THE WATER FLOODING WELLSSun Wenhao；Qiao Ruxun；Yang Wenwu；Li Maoliang（Nuclear Power Institute of China,Chengdu 610005）ABSTRACT The possibility of using ~(113)In~m-Charcoal as a new radiotracer for determining the water intake pro-files in the water flooding wells is studied． The performance of charcoal to absorb ~(113)In~m： the effects ofthe chemistry treatment，size，pH in the medium，the time and temperature of absorption, ratio of char-coal to eluate and other chemical conditions on the performance are tested，from which the optimum ofthe well logging is obtained. The absorption of ~(113)In~m on EDTA-treated charcoal is more than 90％andthere is no desorption of ~(113)In~m in flushing water at 100℃. Hundreds of the water intake profiles in thewater flooding wells have been determined and more than 95％is successful.Key words ~(113)In~m charcoal isotope well logging