Abstract
In November, 2000, prompted by extremely high natural gas prices, steam injection was reduced by 78,000 BSPD (60%) for an extended period in the Potter Reservoir of the MWSS Field located in California. The price environment served to accelerate efforts to reduce injection to the thermodynamic minimum. Production decreased by around 5000 BOPD (SOR ~ 18:1). The Potter formation is a steeply, dipping sandstone reservoir containing 13° API oil and has been under thermal recovery for over 30 years. An extensive surveillance network of observation wells allowed for gathering of high quality heat and reservoir fluid information.
This paper will discuss the theory and approach taken to set lower steam targets. It will also show examples of the impact of lower steam rates on thermally mature properties. Additional unresolved issues concerning our current inability to fully understand the relationship between reservoir (or steam chest) temperatures and oil production rates will also be discussed.
