There is a vast layer of Potash that lies under Saskatchewan and extends far into the United States. This deposit is about 1,000 metres below the surface near Saskatoon and Esterhazy, and is about 1,600 metres deep near Belle Plain, and about 3,000 metres deep in North Dakota. The depth of the resource in the northern US makes it inaccessible at the current time.
The resource was discovered while drilling for oil in 1942 near Radville, and again in 1946 near Unity. The first attempt to develop the resource in Saskatchewan was at Alsask in 1951. A shaft was sunk, and the mining company encountered the Blairmore Formation.
The Blairmore Formation is 200 to 400 foot thick layer - a mixture of sand, shale and water under a pressure of about 700 psi. Early attempts to sink a mine shaft would encounter this layer and the shaft would be flooded with water. The miners attempted to stem the flow of water by using concrete to seal the shaft but the Blarimore Formation resisted any attempt to use this technique. A new approach was needed.
Near Esterhazy it was decided to try a technique used successfully in Europe but which was practically unknown in North America. They would freeze the ground which would hold back the water, and then they could install iron rings as a permanent shaft after the ground thawed out again. They spent a year freezing the ground using 58 "freeze pipes" each 250 feet long arranged in a circle around the mine shaft. The freezing solution was a mind-numbing -50 F and used enough capacity to make ice for 3 Maple Leaf Gardens hockey rinks!
Once the ground was frozen, the shaft was excavated, and about 100 rings weighing 28 tons each were installed and used to create a water tight seal. Finally, the potash that was buried deep below the plains were accessible.
In order to claim this as a find, you need to provide some information about the Blairmore Rings.
Go to the posted co-ordinates, and find the example of the Blairmore ring that is on display.
What is the diameter (total distance across) of this particular ring (to the nearest foot or metre).
How tall is this particular ring?
Given that the Blairmore Formation was 200 feet thick at the first mine site, how many of these rings were required?
What is Potash commonly used for?
Where does the name "potash" come from?