Water Injection Well Fracture Treatments Benton Field Franklin County, Illinois

Abstract

Maintenance of desirable water, injection rates has been a problem at Benton and is a problem to many waterflooding projects. Inability to maintain desirable injection rates is generally the result of plugging by precipitates in the injected water, skin effects incurred during completion, and limited reservoir capacity; Several methods have been used to alleviate this problem in the Benton field~and one of the most successful has been hydraulic fracture treating.Data from 29 fracture treatments of 26 injection wells at Benton show that water injection rates have been sUbstantiall¥ increased. Although the behavior of other injection wells mask the effects of increas ed injection rates in treated wells, total liquid production has been increased in surrounding producing wells without adversely affecting produced water-011 ratios.Fracture treatments have been varied, but an optimum treatment has not been conclusively indic ated. However, results of water-base! treating liquids compare favorably with the results obtained from the use of more expensive acid-base and/or oilbase liquids.The physical nature of the fractures has'been in vestigated by several different injection profiling methods. Pronounced profile changes have not been observed. It appears that existing zones of weakpess in the formation have been extended and that a single vertical or horizontal fracture plane has not occurred.