The Athabasca oil sands

Bitumen under 141,000 square kilometres, and it seeps out of the riverbank on its own

The largest deposit of its kind on the planet: bitumen soaked through sand and clay under 141,000 square kilometres of boreal forest and muskeg in northeastern Alberta, holding an estimated 133 billion barrels of oil in place. The pay is typically 40 to 60 metres thick, sitting on flat limestone under a metre or three of waterlogged muskeg, which is why the northern part of it is dug rather than drilled. The Cree and Dene used the bitumen to waterproof canoes long before Peter Pond became the first European to see it in 1778, and the river carries it: in places the tar seeps out of the cut bank on its own. Production ran around 2.8 million barrels a day in 2023. Whatever anybody thinks of it, this is the single largest industrial thing in Canada and it is worth understanding what is actually under that ground.