Combined Cost-effective Seismic Monitoring Technology for a Shallow Heavy Oil Reservoir Driven by Sagd

Abstract

In case of shallow deposits of heavy oil deploying and exploitation of known high-resolution seismic monitoring system of SAGD based on permanently buried sources and receivers like SeisMovieTM essentially raise a cost of investigations and lead to unprofitable production. The purpose of experiments was to develop a cost-effective seismic monitoring technology for a shallow heavy oil reservoir driven by SAGD. A combined surface-borehole monitoring system was developed. It consisted of a network of measuring wells and sparse grid of seismic profiles. Heat-resistant geophones were permanently buried in wells below the reservoir. Profiles were oriented across a SAGD-wells through a dome of oil trap. At least one profile need to plan for every group of unidirectional SAGD-wells. To control seasonal variations of near surface elastic properties of formation a surface low channel geophone array centered relative to the wellhead was used upon survey. The monitoring system was deployed at one of oil sand bitumen reservoir within Cheremshan-Barstrick group of heavy oil fields, Tatarstan (Russia). Field experiment included base and one monitor surveys performed during the year. The interpretation based on time lapse direct transmitted and reflected P-waves inversion was used to determine temperature changes in reservoir conditions caused by steam injection.