STRUCTURAL GEOLOGY TECHNICAL DIVISION TALK

Wild Card – Natural Fractures in the Duvernay Formation, Western Sedimentary Basin

Presenter: Carolyn Currie, Core Laboratories Canada Ltd

January 7, 2021 | 12:00 pm-1:00 pm Mountain Time 1 CPD (Continuing Professional Development) credit will be awarded for this event ABSTRACT The Duvernay Formation is western Canada’s quintessential organic-rich play that operators keep battling with. It is Devonian in age and diverse in both geographical area and lithological characteristics. The Duvernay is simply the distal, organic-rich end member of the Leduc reefs, however, the distribution of lithofacies (carbonate, mudstones and ) within, complicates matters with a surprise waiting with every core taken. Shales plays are extremely complex systems in which numerous factors are at play when considering if these plays will be economic or not. Allocation of production can come from a number of different places from within the stimulated rock volume (SRV), including the matrix (nano-darcy), unpropped fractures (milli-darcy) and propped fractures (micro-darcy). The wild card in this formula is the presence of a natural fracture network in the SRV and is often poorly understood. The identification of faults and fractures should be part of any good core description process and is especially important when talking about shale plays. This presentation will focus on the wild card – natural fracturing in the Duvernay. Taking a subsurface tour around the Duvernay Formation, looking at key cores, we will identify abundance, type and orientation of the natural fracture network observed. Furthermore, extrapolating and locating these natural fractures along the lateral length can be achieved using a number of technologies, including tracers and drilling log data. Taking learnings made on core and being able to apply it to the lateral can only aid in a more efficient engineered strategy to maximize the ultimate SRV. BIOGRAPHY Carolyn Currie has held key positions as senior geologist and project lead at Core Laboratories, working on various unconventional plays in North America and globally including Duvernay, Montney, Wilrich/Spirit River, Eagle Ford, Marcellus, Midland Basin and Deep-Water Mozambique. She currently serves as the Manager of Rock Properties, leading such projects as the Duvernay, Montney and Wilrich/Spirit River consortia studies in the Canadian office. Throughout her time at Core Laboratories and previous projects (including her master’s project), she had logged, described, interpreted and integrated 500+ cores ranging from unconventional shales, tight sand formations, deep water sandstones, heavy oil/oil sand cores.