The high complexity of diagenetic facies and +hei~1 -*-*.1 . -----Au.-.w-eh.maaa .ffa,-t4"o V..-mrn+ . -..s..~--q...._-.A..~.=-=. "".. . quality can be monitored.A computer-based program haa been used for zonation of wells into electrofacies according to Reservoir quality in the Arab C fncreaaes log responses. The process determines a number of towards the crestal zone due to the occurrence clusters from similar log valuee. of lees anhydrite (F7, F8) in the carbonate facies. To ensure that the electrofacies obtained are geologically meaningful, log responses from key In the Arab D, porous electrofacies F3 and F5 wells were calibrated with geological facies from (porous and dolornitic mudstonea) are well cores. Input logs were selected accordingly.represented in the crestal part of the field but get very thin or pinch out towards the The creation of a data bank helped to obtain flanks. consistency in the twenty-six wells processed in El Bunduq field offshore Abu Dhabi/Qatar.