Cross-border radon index map 1 : 100 000 Lausitz - Karkonosze - Jizera region (northern part of the Bohemian massif)
|Location||International Geological Congress,oslo 2008|
|Author||Barnet, Ivan۱; Pacherova, Petra۱; Preusse, Werner۲; Stec, Bartosz۳|
|Holding Date||07 October 2008|
The cross-border radon index map (LKJmap) at a scale 1 : 100 000 Lausitz - Karkonosze - Jizera region (Czechia - Germany - Poland) represents one of many ways for expressing the radon potential or radon risk. LKJ map is based on 818 original soil gas radon measurements (663 Czech Geological Survey - CGS, 61 Federal Office for Radiation Protection Germany, 94 Polish Geological Institute).
The map uses the vectorised geological map published by Czech Geological Survey as a background and covers the area 19709 km2 between Torgau, Dresden (GER), Liberec, Náchod (CZ) and Boleslawiec (PL). The Czech metodics was applied for characterizing the lithological units by radon index (combination of radon concentration and permeability), which is the classification parameter for the Czech radon risk mapping and building site assessments. (prevailing category of radon index in particular lithological types). For determining the radon index the whole database of the Czech Geological Survey was also implied (9500 test sites) to characterize the lithotypes.
The map was processed and presented in ArcGIS 9.2. programme (layers describing topography, geology and faults, radon index, and input data from soil gas measurements). The map covers the area of the Cretaceous sediments and Tertiary neovolcanites, Palaeozoic sediments and metasediments, Variscan and Cadomian granitoids, orthogneisses, paragneisses and Neoproterozoic metasediments.
The highest soil gas radon concentrations exceeding 100 kBq.m-3 were observed in Varican granitoids of Karkonosze - Jizera pluton (CZ-PL) and monzonites (syenodiorites) of Meissen complex (GER, Dresden), in augengneisses and granite gneisses of Izera metamorphic complex (PL) and partly in Permocarboniferous sediments near Vrchlabi (CZ). The radon release from deeper granitoid bedrock was detected even in tectonically disturbed superficial Cretaceous sediments near Dresden. The map demonstrates the possibility of exploiting the geological information in the field of radon risk prediction and contributes to testing of different methods for the European Atlas of Natural Radiations creation.