Buffalo Head Hills kimberlite field

The Buffalo Head Hills kimberlite field is a group of kimberlitic volcanic pipes or diatremes in north-central Alberta, Canada. As of 2011, 41 kimberlite pipes, of which 28 are diamondiferous, had been identified in the field. They were emplaced during Late Cretaceous to early Paleocene time.

As of 2014 the Buffalo Head Hills field is in the exploration stage and has not gone into production. The highest grade kimberlite pipe (Pipe K252) has an estimated grade of 55 carats per hundred tonnes.

The Buffalo Head Hills (BHH) kimberlite field is part of the Northern Alberta kimberlite province, along with the Birch Mountains kimberlite field and the Mountain Lake cluster. It is located about 400 km (250 mi) north of the city of Edmonton in the Buffalo Head Hills of northern Alberta. The area lies within the Canadian boreal forest and is sparsely settled. Access is via Alberta Highway 88.

Deep beneath the BHH kimberlite field lies a 2.0 to 2.4 billion year old Precambrian craton called the Buffalo Head Terrane, which has no exposure at surface. The Precambrian craton is overlain by about 1,600 m (5,200 ft) of Paleozoic and Mesozoic sedimentary rocks, which are covered by as much as 200 m (660 ft) of unconsolidated glacial and post-glacial sediments of Quaternary age. Because of this thick cover of Quaternary sediments and lack of bedrock outcrops, the BHH kimberlite pipes were discovered primarily through interpretation of geophysical data from aeromagnetic and gravity surveys, followed by drilling programs.

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