Correlation between SAGD Steam Chamber Growth and Geological Heterogeneity

Evolution of Steam Assisted Gravity Drainage (SAGD) steam chambers in heavy oil and bitumen<br>reservoirs is tied to: 1. uniformity of steam pressure and quality along the length of the perforated interval<br>of the well and 2. reservoir geology and fluid properties adjacent to the well. If steam delivery into the<br>injection well is not uniform, then non-uniform steam is delivered to the reservoir along the wellpair. If<br>the reservoir geology has poor permeability at an interval along the wellpair, then steam delivery to and<br>fluids production from the reservoir is not uniform. If the steam is well distributed throughout the<br>injection well, then the key factor for a uniform steam chamber along the wellpair is reservoir geology.<br>This is especially important in highly heterogeneous, variable thickness reservoirs where geology and<br>reservoir oil composition may vary significantly over the length of a wellpair. In this study, heterogeneity<br>of a growing SAGD steam chamber is related to heterogeneity of the underlying geology. Here, the oil<br>sand models are geostatistically populated to model heterogeneity of porosity and permeability.