Upcoming Division Talk
Integrated approach to understand which reservoir characteristics lead to better Montney productivity
12:00 Noon Wednesday, February 15th, 2017
geoLOGIC Classroom (2nd Floor), Aquitaine Tower, 540-5th Avenue S.W., Calgary
The unconventional Montney play is extensive in area as well as in thickness and offers a large range of facies and associated properties. Identification of the best targets and the optimal frac design will rest on understanding the variability in rock properties such as brittleness and pore throat size, the nature of the hydrocarbon in place and the maturity level of the various Montney intervals. Combining inorganic and organic geochemistry with geomechanics and other rock properties can be simple and economically very rewarding.
Published XRD based brittleness formulas have so far fail to address the problem of type and distribution of calcite which can make the rock more brittle (higher Young’s Modulus with increased carbonate cement) or ductile (higher Poisson’s ratio when carbonate pelecypod rich); XRF can directly distinguish between these two types in the Montney using Ca-Mn ratios. Similarly while quartz content may increase brittleness, quartz cement impairs fraccability and can be easily estimated using Si-Zr ratios. Additionally, petrophysics based brittleness has been successfully cross-correlated to single or multi XRF elements, giving tools to better design frac stages in Montney horizontal wells.
Small pore throat size may leave hydrocarbon left behind within the reservoir. A new integrated approach will be discussed that invokes comparing gas composition from chromatography with blended cutting gas. The derived pore throat sizes have been calibrated against the ones based on capillary pressure curves using a new 30% Hg based formula.
Last but not least, is the importance of the maturity level and the distinction between in-situ gas and migrated gas within various part of the Montney sequence. Text book examples of shale dehydration within the Montney will be shown in the in-situ dry gas domain using a very large data set of flow back water geochemistry; all this with the associated potential for soaking/marinating these reservoirs and dramatically improving productivity.
Jean-Yves Chatellier has been working for large oil companies for thirty years and has been focusing on North American shale and tight sand reservoirs for the past nine years. He has published extensively on structural geology, sedimentology, geochemistry and reservoir engineering. He is presently co-chair of the AAPG Research Committee and very active in other societies (CSPG, SPE). He is presently initiating and managing two separate consortia dealing with Montney and Duvernay organic and inorganic geochemistry to optimize frac design.