As industry moves towards waterflooding horizontal wells, monitoring and maintaining the injection profiles has emerged as a reservoir management issue. Heterogeneities in the reservoir, completion design, and completion problems can all contribute to non-uniform injection and a corresponding drop in waterflood efficiency. Knowing where the water is being injected along the length of a horizontal water injection well is critical to maximizing secondary recovery. Operators need to monitor for channeling of water injection between horizontal injectors and horizontal producers and gather information capable of determining the best way to remediate problems. Operators have begun using distributed temperature sensing (DTS) to measure the temperature along a horizontal well and infer the injection profile from that data. Based on this information, a workover can be done to redistribute the injection, resulting in lower watercuts at the producers and improving the secondary recovery factor.
This paper covers the techniques used to determine the injection profile with DTS, focusing on a case history from the Cardium formation in the Pembina area of Alberta. The well and reservoir conditions are summarized, the completion is reviewed (with microseismic data showing fracture geometry on the injection well), the injection profiling methods are covered, and the results are shown. The operator's remedial efforts are then covered, along with preliminary results.