Don's Blog The Smoking Hills I 11-7-17

Going west from Desalis Bay on the southeast corner of Banks Island we crossed Amundsen Gulf just south of the Beaufort Sea heading for the Smoking Hills in the Northwest Territories.  This amazing natural phenomenon is on the western side of Franklin Bay between Cape Bathurst and Cape Parry.

The Smoking Hills are smoking cliffs to the east of the Mackenzie River delta (below) and near the delta of the Horton River. They are about 37 miles in length.

The Smoking Hills were named by Robert McClure in 1850. McClure, on the ship Investigator, was searching for the  Franklin Expedition sailing  from the west approach to the presumed Northwest Passage. Seeing smoke arising from crevices in the cliffs McClure sent his men to check. He departed believing that the smoke was volcanic in origin )below).

Some sources have indicated that John Franklin named the Smoking Hills during his land expedition

of 1825 and 1826. This would not have been possible. During Franklin's third overland expedition to the "polar sea" Franklin and John Richardson descended the Mackenzie River to the sea from Great Bear Lake.The parties separated on July 4, 1826. Franklin's group with officer-artist George Back in the Lion and Reliance

went west to map the shoreline. Richardson's group, in the Dolphin and Union went east to survey the coast between the MacKenzie and Coppermine Rivers. Only Richardson would have seen the Smoking Hills since they are east of the Mackenzie River.

On the day of our visit the waters of Franklin Bay were too rough for us to go ashore.

We were able to see the smoke coming from the cliffs.

The smoke comes from the spontaneous combustion of mud stones which creates boccanes or fire baked rock. The mud stones originated in the Cretaceous period,the age of the dinosaurs (Mesozoic), about 145 million years ago.They contain pirite and lignite. Pirite is iron sulfate (FeS2) also known as fools gold. Lignite or brown coal, is a soft combustible sedimentary rock

formed from naturally compressed peat. The landslide strata of these mud stones are exposed to atmospheric oxygen with resultant oxidation that results in the high temperature required for the autoignition and spontaneous combustion of the coal. This is facilitated by the fine particle size and large surface area  of the pirite. As specific areas burn out new areas begin burning. This has been going on for hundreds of years. It results in bleaching and reddening of the stone.