Study on water rising mechanism and capacity enhancement in Wenchang13-1 oilfield

Overall water cut of Wenchang13-1 oil field has come to 60% and oil production rate dropped obviously compared with that of the early producing stage.Water rising mechanism was studied and according measures were proposed in order to maintain a reasonable producing rate and enhance the ultimate recovery in the economical period.Results show that the structure,reservoir heterogeneity as well as liquid production per unit thickness are the essential factors influencing water rise and development effect.Taking Wenchang13-1 oil field as an example,measures of stuck layer,withdrawing liquid,acidizing break down and plugging water were developed according to the special conditions of offshore production and water rising laws of different types of reservoirs.Field practice show that the method can enhance capacity greatly and delay ascending velocity of water cut effectively,and thus can provide useful reference to the oil field balance production.