Relating 4D Seismic and Production Data to Determine Steam Displacement Efficiency in SAGD Reservoirs

Summary Steam assisted gravity drainage, known as SAGD, has become a standard recovery technique for the oil sands of northern Alberta, however there are still significant challenges associated with using steam efficiently. The main controlling factor on SAGD economics is steam chamber size and shape (volumetric sweep efficiency). This paper will show how 4D seismic data has been used on a number of SAGD projects to define the steam chamber size and shape, for three different SAGD projects. By combining production data with 4D seismic data it is possible to infer the drainage efficiency of the injected steam. This workflow is a critical as it helps the operator characterize the remaining oil in place, it justifies additional expenses to increase ultimate recovery, and optimizes the production potential of a well pair or pad.