Brian A. Rottenfusser1,
(1) Oil Sands Geological Associates, Calgary, AB
(2) Japan Canada Oil Sands Limited, Calgary, AB
Abstract: Development of a SAGD Pilot in the Athabasca Oil Sands
Over the past 15 years, Steam Assisted Gravity Drainage (SAGD) has emerged as a proven technology for in situ exploitation of the Athabasca Oil Sands in northeastern Alberta, Canada. Several oil sands pilots have been established to develop the technology under different reservoir parameters. Recently, Japan Canada Oil Sands Limited (Jacos) has started a SAGD pilot test at Hangingstone, 50 km south of Fort McMurray. Five horizontal well pairs have been drilled, each consisting of a horizontal injection well overlying, by about 5 metres, a production well. The first two pairs are 500 metres long, while the other three pairs are 750 metres long. Delineation wells to define the reservoir were drilled in several phases. Results of each phase of drilling were used to plan the next round of drilling, and even to change the location and orientation of the horizontal wells.
Planning the extraction process requires a very detailed knowledge of the facies, their reservoir properties and their three dimensional relationships in order to place the horizontal wells and predict the movement of steam through the reservoir. The rich McMurray Formation oil sand channels which the Hangingstone pilot seeks to exploit were deposited in estuarine channels near the mouths of northward flowing rivers into the Lower Cretaceous Clearwater Sea. The active cut and fill of the estuarine channels deposited a complex reservoir of clean channel sands, with accessory mixed sands and shales deposited in point bar and channel margin environments. These are surrounded by muddy tidal flat sediments. Extensive bioturbation has fully or partially homogenized some facies and left a rich ichnofossil suite.
AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana