History of Mining: The evolution of shaft sinking systems (Part 4 of 7) – by By C. Graham and V. Evans (CIM Magazine – February 2008)


Shaft sinking from 1900 to 1940: start of the Modern Era

Mine shafts sunk during 1900 to 1940 in North America were almost all rectangular, timbered shafts while in Europe nearly all were circular and lined with brickwork or concrete. The reason for this was ground conditions. The majority of North American shafts were sunk in hard, competent rock. In Europe, on the other hand, the majority of the shafts sunk were in soft sedimentary rock, often with major water-bearing strata.

This was a busy period for shaft sinkers in a number of areas in the world. In the Ruhr district of Germany alone over 200 shafts were sunk: 124 shafts (1904–1914); 71 shafts (1915–1932); 13 shafts (1933–1940).

This was also an exciting time for the Canadian mining industry, with many of the famous mining camps opening up from 1900 to 1940. After the discovery of silver in Cobalt, Ontario, in 1903, prospectors ranged widely over the Precambrian areas of Ontario, Quebec, Manitoba, Saskatchewan and the Northwest Territories. In Ontario and Quebec, Abitibi and Larder Lake were discovered in 1906, Porcupine in 1909, Swastika in 1910, Kirkland Lake in 1911, Matachewan in 1916, Rouyn-Noranda in 1924 and Red Lake in 1925.

In Manitoba, the Rice Lake district was discovered in 1911, and in the Northwest Territories the deposits in the sediments in the Yellowknife area were discovered in 1933 and those in the greenstones in 1935. In Saskatchewan, the Box and Athona mines were discovered in 1934 and three shafts were sunk at these properties in the La Ronge gold belt.

In British Columbia, bedrock gold deposits first attracted attention in 1863 during the first great placer gold rushes in the province. Little work was done on any of the discoveries and most were forgotten. The Barkerville area was prospected in 1860 and some mining was done in 1876 and a few years thereafter. Large-scale mining, however, did not commence until 1933 and 1934 at the Caribou Gold Quartz and Island Mountain mines.

In 1897, the Cadwallader gold belt in the Bridge River district, containing the Bralorne and Pioneer deposits, was prospected, but it was not until 1928 that the Pioneer mine was brought into production, followed in 1932 by the Bralorne mine. The Premier mine in the Stewart district was brought into production in 1918 and the Zeballos gold belt on the west coast of Vancouver Island was discovered and developed starting in 1934.

In addition to all this shaft sinking activity, coal mining continued to attract attention in Nova Scotia, and over 100 new coal mines were opened in that province during the 1900 to 1940 period. Shafts in this area tended to be relatively shallow, however, generally less than 800 feet deep. This is in comparison with the McIntyre No. 11 Shaft that was sunk to a depth of over 4,000 feet in the Precambrian rock of Ontario. All in all, it is estimated that over 400 shafts were sunk in Canada during this time.

Late in the 19th century, gold had been discovered in the Johannesburg area of South Africa, and from 1910 to 1948, 341 rectangular, 41 circular and seven elliptical shafts were sunk.

The introduction of compressed air and electrical power into mines at the beginning of the 20th century had a great impact on shaft sinking practices.

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