Publications

Reservoir Surveillance is a key component in subsurface heat management and horizontal well development of Duri Field Steam Flood. Reservoir surveillance surveys are conducted in the observation, injector, and producer wells to measure steam flood parameters and activities such as fluid and reservoir temperature, fluid saturation, injection split, potential subsurface hazards, and water aquifer influx. The Asset Optimization & Development Team has been managing the reservoir surveillance budget, survey operation, and utilization of the log data. Annually, the Duri Steam Flood spends around six million dollars for bore-hole wireline surveillance including temperature logs, carbon-oxygen logs, pulse neutron captures and steam decay logs, pressure measurements, spinner measurements, krypton tracer measurements, and optical temperature sensing logs. Surveys are conducted in more than 600 observation wells and 150 injector wells every year, and are utilized to review more than 1800 steam flooded patterns. In 2016-2017, reservoir surveillance drove the decision to cut steam injection more than 240 MBSPD, resulting in more than $80MM of operating expenditure savings with no production impact. The reservoir surveillance was also the key information used in selecting and executing more than 60 horizontal wells drilled in 2016-2017. In order to deliver an effective program with optimized operating expenditure spending and safe operation, the team developed governance of candidates screening workflow and standard operation procedure for each type of job. The governance covers the structure of submission & approval process, tracking system, quality control procedure, and database management. Several lean sigma projects have been completed or are ongoing to continually improve and streamline the process to optimize these efficiencies.