Boasting 178 billion barrels of proven oil reserves and close to 58 Tcf of proven natural gas reserves as of 2009, Canada is the world's largest reserve holder after Saudi Arabia and the top supplier of U.S. energy imports. Canada is also home to the world's most expansive oil sands deposits, the development of which extracts and processes a heavy, tar-like crude bitumen that comprises the bulk of the country's reserves. Canada's oil and natural gas sector is privatized, with industry regulation occurring at the provincial level.
Drilling fluids, also referred to as drilling mud, are added to the wellbore to facilitate the drilling process by suspending cuttings, controlling pressure, stabilizing exposed rock, providing buoyancy, and cooling the drill bit. Mud engineers ensure that the drilling mud that is used is made to the required specifications based on the expected geology. Drilling fluids can be water, oil, or synthetic-based, and mud engineers must take rock formation composition, as well as environmental impact, into account when making decisions about what drilling fluids might be best for any given well.