This paper reviews the design and implementation of a full field inter well tracer program of a giant onshore oil field in Abu Dhabi. The field is under peripheral waterflooding in order to maintain reservoir pressure and provide a mechanism to sweep the oil. However, the existence of the strike-slip fault planes juxtaposed across the reservoirs added a variable to the complexity of the waterflood management. In order to improve the understanding towards the reservoir heterogeneity and reduce the uncertainties associated with major faults, a full field water tracer program which is possibly the largest in the Middle East has been designed.
Based on streamline model, unique chemical tracers have been injected in twenty three water injectors covering all the peripheral areas and dozens of associated offset producers across the field were selected to monitor the tracer movement. The program have been designed carefully in terms of tracer selection & compatibility test, chemical volume calculation, injection well and monitoring well selection, as well as the devise of the comprehensive monitoring plan. Ultimately the results of this tracer program will be used in combination with other reservoir surveillance tools to facilitate a better management of the reservoir.
Interwell tracers technology is a valuable tool for reservoir management, however, reliable tracer data can only be obtained through judicious design, implementation and monitoring. The preliminary results from designing the tracer program include: 1) Twenty three water injectors were identified based on streamline modeling for tracer injection and dozens of producers for monitoring. 2) Injected tracers were selected based on the uniqueness, stability, detection limit and environmental friendliness, and compatibility tests were done in advance between tracers and reservoir fluids. 3) Total dilution method was used to calculate the quantity of tracers injected in each of the well. 4) A comprehensive monitoring program was scheduled to capture the arriving of the tracer as well as to depict the entire tracer wave.
The presented full field water tracer program of a giant onshore oil field is possibly the largest in Middle East, and the described designing of the program, encountered problems and best practice could be of some use to those intended planning a tracer project.