The Determination of 222Rn in Drilling Fluids of the KTB Pilot Borehole Using SSNTD Techniques

²²²Rn dissolved in drilling fluids of the KTB (Kontinentales Tiefbohrprogramm der Bundesrepublik Deutschland) pilot hole has been determined using solid state nuclear track detector (SSNTD) technique:The α-sensitive SSNTD CR-39 was used to measure the a-activity of ²²²Rn. Well-defined conditions for Rn-measurements could be established by employing a mica nuclear track microfilter to separate the detector containing air volume from the volume containing the water. This technique has been applied to determine quantitatively the ²²² Rn-concentration as a function of depth of the borehole down to 4000 m.