Advance on the Tracer Test Technology Among Wells

Abstract

Abstract The development of the tracer test technology among wells in oil fields has been reviewed in this paper. Both advantages and weakness about the tracer test among wells from the first generation to the fourth generation have been briefly analyzed, meanwhile, a more systematic technology, i.e. comprehensive static and dynamic analyses method has been raised here. The authors proposed that the fourth generation technology with professional interpretation and comprehensive analysis had more advantage. This technology applied in the reservoir development of water drive, steam soak and immiscible displacement has been shown and discussed. Meanwhile, the evaluation on several relevant methods that have been widely used in China has been briefly discussed here. In conclusion, the tracer test technology among wells should be a mature and advanced method during the oil field development at the present age, it should have a widely and excellent prospect of application. Introduction The development of oilfields was a way to cognize characters of reservoirs step by step. Generally the development of a block needed at least several wells, so one of the brief cognizance was the degree and effect of inter well interference in water drive reservoir, steam soak reservoir or some special style reservoirs. At the beginning of exploitation and development, the direction of fractures, the degree of heterogeneity and the effect of injected water ought to be considered. In the course of development, the utilization efficiency of injected water, the displacement status among wells, the source of produced water ought to be found out. At the end, whether the high-permeability channels existed, the evaluation of development and the distribution of oil saturation ought to be cognized or done. All of the above could benefit from inter well tests. The results of the tests were valuable to the evaluation and the adjustment in reservoir development. Only a few of direct and audio-visual methods have been applied in cognizing the parameters between wells. One of them was the tracer test technology among wells, which have been tested and applied in the worldwide. At same time, all the elements in tracer test, including the design theory, injection technology, sampling system, interpretative method and software, have been researched and summed up to a series. In 1965, Brigham W.E. and Smith Jr. D.H. introduced a simple model to predict the breakthrough time and the peak concentration of tracer in five-point pattern1. In 1971, Cooke put forward applying chromatogram theory in oil saturation measurement2. Subsequently, Abbaszadeh-Dehghani Maghsood and Brigham W.E. ameliorated the semi-analytical model and provided the analytic expressions considering radial dispersion in streamtubes3. Recently, many deep studies on fieldwork and theory have been done, and the results of them were excellent and exciting4. With the development of computer technology, some interpretative software have been programmed and applied to interpret the tracer tests in oil field, including numerical method, analytical method and semi-analytical method. Meanwhile, the range of reservoir parameters interpreted became more and more wide with better precision, so managers in oil field have accepted this technology.