The paper presents the results of pilot run of cyclic steam stimulation on the carbonate reservoir saturated with bitumen. Some aspects of well performance and reaction of the reservoir to steam injection in two pilot areas are considered. The paper also describes the case of cyclic steam stimulation history matching in the first pilot area based on the theory of natural fracture reactivation by applying high injection pressure. The modelling results show good correlation between actual and calculated data. Based on data of continuous temperature monitoring from fiber optic measurement system installed in the well it was possible to locate steam intake intervals. These intervals are consisted of rocks of much less porosity and bitumen content and at the same time developed system of fractures. The results of the pilot run show that the development of the reservoir M by means of vertical wells in the zones of distribution of such rocks, which cover 50% of the area of the reservoir, can be technically and economically effective. For areas of lower net thickness and lateral extension of low porosity fractured intervals, three cases of steam stimulation in the system of horizontal wells are considered. The first of the considered cases is steam – assisted gravity drainage, and the other two cases are cyclic steam stimulation on horizontal wells, which differ from each other by the distance between the wells. Third option proved to be the best out of 3 considered – cyclic steam stimulation with a distance between wells of 50 m. The characteristic of displacement of the calculated forecast variants are similar to the actual characteristics of displacement at steam stimulation on analogous oil fields that confirms accuracy of modeling results.
In the near future, it is planned to conduct pilot works to test technologies of steam-assisted gravity drainage and cyclic steam stimulation in horizontal wells.
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