ELECTRICAL D-C RESISTIVITY MEASUREMENTS ON GLACIER ICE NEAR THULE, GREENLAND
The results of electrical d-c resistivity measurements carried out at the surface of cold glaciers near Thule and on the firn of the Greenland ice sheet as well as inside excavations in glacier ice are reported. A resistivity of the order of 100 kilo-ohm-m was found in the firn at temperatures of ab...
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Format: | Text |
Language: | English |
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1962
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Online Access: | http://www.dtic.mil/docs/citations/AD0292935 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0292935 |
Summary: | The results of electrical d-c resistivity measurements carried out at the surface of cold glaciers near Thule and on the firn of the Greenland ice sheet as well as inside excavations in glacier ice are reported. A resistivity of the order of 100 kilo-ohm-m was found in the firn at temperatures of about -24C and in glacier ice at about -12C, as opposed to values of many megohm-m in temperate glaciers as reported in the literature. An indication was obtained of considerably higher resistivities than 100 kiloohm-m in the ice of a long valley glacier and close to the bottom of thin glaciers with little movement. The interpretation in terms of ice thickness proved to be highly ambiguous, and the resistivity method was accordingly of little use for sounding purposes under the conditions encountered. Non-linear phenomena were observed with small electrode separations inside the excavations. Recommendations are made on the construction of a field instrument for measurements on glaciers or other high resistivity material. (Author) |
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