The Approbation of Reserves Geochemical Control Technology in Example of AC10 and AC12 Group Formation in Priobskoye Field of LLC Gazpromneft-Khantos

In order to improve tools for monitoring the reserves recovery and localization at the Gazprom Neft fields, as part of the technological strategy, a technology for geochemical control of reserves recovery has been developed. The use of geochemistry methods in identifying the targeted flow of fluids from a reservoir is based on the difference in fluids’ composition and properties from reservoir to reservoir. According to laboratory experiments, the accuracy of the geochemical predictions of miscibility based on a multiple linear regression model varies from 1 to 8% for oils and condensates, from 6% to 18% for gases, and from 15% to 34% for reservoir water (provided there is no pressure maintenance system in a reservoir). The technology was tested at Priobskoye field of Gazpromneft-Khantos LLC, which jointly operates Zones AS10 and AS12. The pilot program included 5 wells with pre-installed Y-tool assemblies. The advantage of this system is the ability to conduct tests in a well producing in a stable state with induced pressure drawdown. Simultaneous geophysical studies and wellhead sampling for geochemical studies allowed us to confirm matching of the results of dividing the inflow under the conditions of a well draining two or more target zones. The technology for geochemical control of reserves recovery will allow a breakthrough in the study of wellhead fluid samples in the near future, and such information will increase the success rate and information content of field geophysical studies by an order of magnitude. The advantage of the described technology is 100% coverage of the production well stock and the ability to predict miscibility for all types of fluids (oil, gas, and produced water).