16. January 2009
Ground Temperature Measurements from a deep borehole at Iškoras, Finnmark,
person for additional information: Herman
and photos by Herman Farbrot and Ketil Isaksen
September 25, 2008
, a 58.5 m deep borehole was drilled at Iškoras (69°18’N, 25°21’E, 595 m
a.s.l.) in Finnmark, northern Norway, as part of the project PYRN-TSP
(Permafrost Young Researchers Network’s, Contribution to the Thermal State of
Permafrost Project in the Nordic Countries) [http://pyrn.ways.org/]. During
drilling ground ice was detected (see photo below). Unlike the previous 10.7 m
deep borehole at Iškoras (established September 2007) this new borehole is
located in a 1.5-2 m top layer of fine-grained soil. The borehole was
instrumented with a thermistor chain in the upper 10 m, which was connected to a
Cambell datalogger. UTL-1 and UTL-3 Mini Temperature Dataloggers were installed
at greater depths.
ice collected during drilling at Iškoras
on 25 September 2008.
January 16, 2009
, the first ground temperatures were collected from the new borehole (see
diagram below). Data showed that the temperatures close to the surface were -10°C.
The measured temperatures between 3 and 55 m depth were all between −0.5
and 0°C. Hence, the borehole is situated in permafrost. During the visit, large
areas of the mountain ridge, including the borehole site, were free of snow due
to strong winds, as experienced during the BTS
survey in early March
16 January 2009.