Reservoir Characteristics and Light Hydrocarbon Channeling Revealed by Production Data: A Case Study of Liquid Rich Duvernay Shale Play with Emphasis in Fox Creek Area, Alberta Canada

This paper reports the findings on the major factors affecting the hydrocarbon productivity and ultimate resource recovery from the liquid-rich Duvernay Shale play in the Fox Creek area. Essential completion parameters, production rate, estimated ultimate reserves from monthly production time series and key geological variables were mapped and combined with statistical data analysis to reveal their spatial variation and statistical relationships among these parameters and variables. We found that fluid type of the hydrocarbons in shales is the most essential for hydrocarbon productivity and estimated ultimate recovery (EUR) in this area, while formation pressure appears to be mostly influential in the early production period. Although the genetic parameters from organic geochemistry and geology are essential in mapping the boundary of the resource play, and determining the hydrocarbon fluid types and their spatial variations, moderate to weak correlations to the productivity and ultimate recovery suggest that those genetic parameters are secondary in measuring productivity and recovery. Gas-to-oil ratio (GOR) mapping from produced fluids reveals high GOR channels or linear zones in low maturity areas that are inconsistent with thermal maturity trends spatially, indicating redistribution of hydrocarbon fluids in the source rock in pre-existing permeable networks. Major earthquake swarms induced by hydraulic fracturing appear to be associated with crossing formation faults, and are spatially coincident with reduced productivity and ultimate recovery in de-pressured reservoir. These findings provide insights to better understand the distribution of production sweet spots and production optimization strategies to facilitate a low carbon energy transition.