Overview

The Middle Triassic Halfway and Doig Formations of West Central Alberta comprise a number of siliciclastic shoreline packages deposited on a broad, shallow marine cratonic shelf.  Several major unconformities have been identified and mapped throughout the section.  In this study a significant unconformity is recognized at the base of the Charlie Lake Formation and this surface progressively truncates the underlying sandstones of the Halfway and Doig Formations.

Anhydrite and red beds of the Charlie Lake Formation, developed above the unconformity, combine to create a series of sandstone subcrop belts capable of trapping hydrocarbons.  This study identifies and maps each of these subcrop belts to delineate prospective sandstone trends.

The study area is located in West Central Alberta from Township 70 to 80 between Ranges 1W6 and 13W6.  Within the study area 1610 wells were selected from over 2900 wells that penetrated the Halfway/Doig Formations, and  core from 526 wells (over 9,000 metres) were described and interpreted at the AEUB Core Research Centre.

Click globe for map of study area.

The study area covers 137 townships (12,000 square kilometres) and includes the Wembley, Sinclair, Hythe, Grande Prairie, Teepee, Woking, Valhalla, Rycroft, Spirit River, Progress, Pouce Coupe South & Pouce Coupe field areas:

• fully illustrated text (96 pages) documenting stratigraphy, depositional setting, play types & exploration potential, core descriptions, and database;
• 7 regional and 20 field cross sections;
• 20 maps showing isopach, structure, gross sandstone & hydrocarbon potential at 1:50,000 & 1:150,000 scales;
• 16 stratigraphic picks and isopach values from Base Nordegg Fm. to Top Montney Fm., including Charlie Lake Fm. (Boundary Mbr.), Halfway Fm., Doig Fm. (G, F, E, D, C, B, A Units), and Montney Fm.;
• 1610 well database available in digital and hardcopy formats;
• 526 core descriptions (9,000 metres) with internally consistent correlations;
• 65 thin sections and 16 potential source rock samples;
• play-types (up-dip erosional truncation, erosional remnants, Doig stratigraphic traps).