Production Evaluation Of The Viking Kinsella B Pool Unit No.1

Abstract

Abstract This paper discusses the methods utilized to evaluate the effectiveness of the water flood in the Sparky sand of Petro Canada's Viking Kinsella B Pool, Unit No.1. A sector of the field with high remaining oil saturation was investigated thoroughly by techniques such as examining well-by-well production data, injection efficiencies, pulsed neutron-capture logging of selected producers and subsequent production testing. Production data obtained after reperforation indicated a 2–3 fold increase in oil production in a majority of the wells tested. There appears to be a correlation between the depletion in the Sparky horizon and the perforated interval based on the pulsed neutron log data and recompletion results. The corrective programs included optimization of individual flood pattern voidage replacement and increased drawdowns in some wells with high fluid levels. Recent data, along with suggestions for future programs, will be outlined. Introduction The Viking Kinsella B Pool Unit No.1 is located northwest of Wainwright in east central Alberta (Fig. 1). The producing horizon is the Sparky sandstone which occurs at an approximate depth of 670 m. Primary production commenced in May1973 and continued until February 1976 when the field was converted to an inverted nine-spot waterflood. Peak production of 1500 m3 of oil per day was attained in September 1978. By August 1982 production had declined to about 720 m3 of oil per day (Fig. 2). An evaluation was initiated in Petro Canada's Edmonton office to determine if this decline could be arrested. The northeast sector of the field (Fig. 3) was examined by running production and injection logs. In addition, current and cumulative production data pressure and injection efficiencies were reviewed. Subsequent production testing was done to validate the results. There was some concern over the capability of the pulsed neutron-capture results to evaluate water-flooded producing wells. This paper will outline the techniques used to establish an interpretation procedure which can be effectively used to evaluate production efficiency in waterfloods of this nature. Reservoir Description The Viking Kinsella B Pool produces from a Sparky sandstone reservoir of Lower Cretaceous age. The reservoir is a combined structural-stratigraphic trap of marine origin. The, reservoir rock is a very fine to fine-grained, well sorted quartzose sandstone uniformly deposited throughout the area. The porosity and permeability decrease with depth. This porosity permeability trend is more pronounced in the lower half of the sand. The Sparky reservoir is overlain and sealed by massive grey shale with interbedded muddy sandstone and siltstone. The pool is situated on the southwest flank of the Wainwright High, a localized uplift possibly caused by doming of Paleozoic salt. There is a southwest dip to the reservoir related to this proximity to the Wainwright High. Another very gentle south-southwest dip was caused by sedimentary deposition on the western side of the Pre-Cambrian shield. Localized dips also occur, caused by the undulating surface of deposition. The southwest and south-southwest dips were responsible for the migration of hydrocarbons.