Development Of The Dipole Model For Investigating Of Tracer Flow In Fractured Basement Reservoirs

With the aim of extracting more reservoir information from tracer test, numerous analytical models have been developed since 1960 decade. However its applications are only suitable for sedimentary or layering reservoirs and hard to apply for Fractured Basement Reservoirs (FBRs) due to difference in flow geometry and heterogeneity structures. This paper has developed a semi-analytical model by streamtube method of Abbaszadeh-Brigham for characterizing of tracer flow in the dipole flow geometry in FBRs. Dipole model is a 2-D fractured plane in which water is injected at the bottom and produced at the upper part of the plane. The study consists of an analytical solution for predicting of tracer breakthrough and verification of this solution by mean of physical experiments and numerical simulations. Firstly an analytical solution for tracer breakthrough was derived by succeeding the direct-line solution of Abbaszadeh then the physical model was built in form of a glass bead filled box with the size of 117.5 x 47 x 2 cm on which 6 valves were placed equidistantly for playing role of injection and production wells. Verifications showed a good match between analytical solutions and physical experiments as well as the results of numerical simulations running by UTChem - a reservoir simulator developed by University of Texas that indicates the solution can be used in the next development steps of dipole model for investigating of tracer in Fractured Basement Reservoirs. (author)