Thewater flood project is able to span for many years, it is monitoredby engineers manning its work routinely and continuously. Again, theengineers do use the technical studies that are specialized and moredetailed like the studies of numerical full field reservoirsimulation. Several avenue are available that can improve and modifywaterflood through acquisition and analysis of data. There arecrucial areas that comprise the information which enriches thewaterflood and they comprise of the basics of monitoring, specialdata acquisition, routine data gathering, techniques used to analyzesimple and sophisticated waterflood and the nomenclature (Waterfloodmonitoring, 2015).
Thewater flood basics analysis concentrates on the concepts of materialbalance. In this, the waterflood is operated as the process of voidage-replacement. In addition, the earliest techniques that were usedto monitor waterflood include maps, simple plots and calculations.Dyes etal.,1954 reveals the plots used estimating water breakthrough togetherwith post breakthrough behaviors of varying configuration ofwaterflood pattern. Moreover, the routine data gathering areessential for the calculations done by engineers. These comprises ofthe production rates of daily gas, oil, and water and injection ratesfrom well-by-well , pressures from injection wellhead and thepressure data from well production (Waterfloodmonitoring, 2015).
Inaddition, the acquisition of special data can take place during thewaterflood. Tis technique enables to determine the locations that arefully loaded, partially flooded and the intervals of unfloodedreservoirs in the new wells as well as the already existing well thatare producing. More importantly, in cases where the wells are drilledlater during waterflood, the distribution of residual oil saturationcan be generated by applying special tracer tests or the proceduresof special coring. Similarly, the technique of 4D-sesmic has beendeveloped recently to determine the direction water moves frominjection wells, and it enables to identify the sections of reservoirpay interval that are connected properly and the ones which are not.
Thesimple techniques of waterflood analysis ensure that the water isinjected into the wells according to the rates targeted, as well asensuring the wells are receiving the appropriate share. The engineersnormally determine the amount of water expected to flow to everyinjector before waterflood starts. Again, the bubble map is appliedin visualizing relative and advance volumes of injected water asshown below.
Figure.1- Layer injection-bubble map for voltage Block 3 FO sand interval-LBU of the Wilminton oil field in California (Woodling etal.,1993)
Moreover,the sophisticated technique of monitoring waterflood incorporates themodern numerical reservoir simulator that analyses waterfloodcorrectly. Similarly, the procedure is applied with updated match ofhistory after every five to ten years (Waterfloodmonitoring, 2015).
Eventually,the nomenclature includes fwrepresenting fractional flow of water Fpvgrepresentingthe fraction of displaceable pore volume that is gas saturated Sorwrepresenting residual oil saturation to waterflooding, fraction PVand Swirepresenting fraction PV and initial water saturation(Waterflood monitoring, 2015).
Dyes,A.B., Caudle, B.H., and Erickson, R.A. 1954. Oil Production afterBreakthrough—as Influenced by Mobility Ratio. Trans., AIME 201:201. http://dx.doi.org/10.2118/309-g
Waterfloodmonitoring (2015). Retrieved fromhttp://petrowiki.org/Waterflood_monitoring
Woodling,G.S., Taylor, P.J., Sun, H.H. et al. 1993. Layered WaterfloodSurveillance in a Mature Field: The Long Beach Unit. Presented at theSPE Western Regional Meeting, Anchorage, 26–28 May. SPE-26082-MS.http://dx.doi.org/10.2118/26082-MS