The Study Of Permafrost

Although the existence of permafrost had been known to the inhabitants of Siberia for centuries, scientists of the Western world did not take seriously the isolated reports of a great thickness of frozen ground existing under northern forest and grasslands until 1836. Then the Russian naturalist Alexander Theodor von Middendorff measured temperatures to depths of approximately 100 metres (330 feet) of permafrost in the Shargin shaft, an unsuccessful well dug for the governor of the Russian-Alaskan Trading Company, at Yakutsk, and estimated that the permafrost was 215 metres (about 700 feet) thick. Since the late 19th century, Russian scientists and engineers have actively studied permafrost and applied the results of their learning to the development of Russia's north.

In a similar way, prospectors and explorers were aware of permafrost in the northern regions of North America for many years, but it was not until after World War II that systematic studies of perennially frozen ground were undertaken by scientists and engineers in the United States and Canada. Since exploitation of the great petroleum resources on the northern continental shelves began in earnest in the 1970s, investigations into subsea permafrost have progressed even more rapidly than have studies of permafrost on land.

Alpine permafrost studies had their beginning in the study of rock glaciers in the Alps of Switzerland. Although ice was known to exist in rock glaciers, it was not until after World War II that investigation by geophysical methods clearly demonstrated slow movement of perennial iceā€”that is, permafrost. In the 1970s and 1980s, detailed geophysical work and temperature and borehole examination of mountain permafrost began in Russia,

China, and Scandinavia, especially with regard to construction in high mountain and plateau areas.

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