2006
Sitarek, A.; Badera, J.; Lizurek, G.
Natural radioactivity of selected rocks from the vicinity of the Rožná uranium deposit Proceedings
vol. 29, no. 395, 2006, ISSN: 0138015X.
@proceedings{2-s2.0-34247895741,
title = {Natural radioactivity of selected rocks from the vicinity of the Rožná uranium deposit},
author = { A. Sitarek and J. Badera and G. Lizurek},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-34247895741&partnerID=40&md5=1a63f19b7ba42a394c7be4cb958d0152},
issn = {0138015X},
year = {2006},
date = {2006-01-01},
journal = {Publications of the Institute of Geophysics, Polish Academy of Sciences, Series M: Miscellanea},
volume = {29},
number = {395},
pages = {281-289},
abstract = {The aim of the paper is to present preliminary results of studies of natural radioactivity of selected rocks from the Vysočina region occurring relatively close to the Rožná (Czech Republic) uranium deposit. Measurements allowed to determine the activity concentrations of 40K and nuclides from 238U and 232Th series in investigated rocks and compare the noted activities with average activity concentrations of these radionuclides in the continental crust and soil. Appearance of regional natural radioactivity anomaly could be determined on the basis of the obtained results.},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
The aim of the paper is to present preliminary results of studies of natural radioactivity of selected rocks from the Vysočina region occurring relatively close to the Rožná (Czech Republic) uranium deposit. Measurements allowed to determine the activity concentrations of 40K and nuclides from 238U and 232Th series in investigated rocks and compare the noted activities with average activity concentrations of these radionuclides in the continental crust and soil. Appearance of regional natural radioactivity anomaly could be determined on the basis of the obtained results.
2005
Malczewski, D.; Sitarek, A.; Żaba, J.; Dorda, J.
In: Przeglad Geologiczny, vol. 53, no. 3, pp. 237-244, 2005, ISSN: 00332151, (11).
@article{2-s2.0-17344366488,
title = {Natural radioactivity of selected crystalline rocks of the Izera Block (Sudetes, SW Poland) [Promieniotwórczość naturalna wybranych skał krystalicznych bloku izerskiego]},
author = { D. Malczewski and A. Sitarek and J. Żaba and J. Dorda},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-17344366488&partnerID=40&md5=fe5035d50417a0636303765039b33df7},
issn = {00332151},
year = {2005},
date = {2005-01-01},
journal = {Przeglad Geologiczny},
volume = {53},
number = {3},
pages = {237-244},
abstract = {Results of natural radioactivity of 40K, 208Tl, 212Pb, 212Bi, 214Pb, 214Bi, 228Ac and the fallout of 137Cs measured in situ in typical crystalline (both igneous and metamorphic) rocks of the Izera Block (Sudetes Mountains; southwestern Poland) using a portable gamma-ray spectrometry workstation are presented. The highest activity concentrations of 40K and 226Ra (238U series) were noted in laminated gneisses whereas the highest activity concentration of 228Ac (232Th series) is characteristic for Sn-bearing mica schists. The lowest activity concentrations of 40K, 228Ac and 226Ra refer to the basalts, flaser gneisses and Izera granites, respectively. The measurements carried out in the study area have shown relatively low level of 137Cs fallout.},
note = {11},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Results of natural radioactivity of 40K, 208Tl, 212Pb, 212Bi, 214Pb, 214Bi, 228Ac and the fallout of 137Cs measured in situ in typical crystalline (both igneous and metamorphic) rocks of the Izera Block (Sudetes Mountains; southwestern Poland) using a portable gamma-ray spectrometry workstation are presented. The highest activity concentrations of 40K and 226Ra (238U series) were noted in laminated gneisses whereas the highest activity concentration of 228Ac (232Th series) is characteristic for Sn-bearing mica schists. The lowest activity concentrations of 40K, 228Ac and 226Ra refer to the basalts, flaser gneisses and Izera granites, respectively. The measurements carried out in the study area have shown relatively low level of 137Cs fallout.
2004
Malczewski, D.; Popiel, E. S.; Sitarek, A.
57Fe Mössbauer study of stilpnomelane and associated chlorite from Polish granite pegmatites Proceedings
vol. 49, no. SUPPL.3, 2004, ISSN: 00295922, (4).
@proceedings{2-s2.0-33646001388,
title = {57Fe Mössbauer study of stilpnomelane and associated chlorite from Polish granite pegmatites},
author = { D. Malczewski and E.S. Popiel and A. Sitarek},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33646001388&partnerID=40&md5=ce297b1498f0f796b533f9a4d9b9f440},
issn = {00295922},
year = {2004},
date = {2004-01-01},
journal = {Nukleonika},
volume = {49},
number = {SUPPL.3},
pages = {S43-S48},
abstract = {This paper reports the results of 57Fe Mössbauer study of stilpnomelane K0.6Fe6(Si8Al)(O;OH) 27·2H2O from Żółkiewka (Lower Silesia; Poland). Stilpnomelane in paragenesis with chlorite, tourmaline, claevelandite and zeolites has been found in granite pegmatites in quarries at Żółkiewka. The samples of naturally weathered stilpnomelane and chlorite from the same fragment of rock were also studied. The Mössbauer spectrum of an untreated sample could be fitted to two Fe2+ doublets and two Fe3+ doublets. The Fe2+ doublets have similar isomer shifts, but they distinctly differ in values of quadrupole splittings. Ferric iron, octahedrally coordinated occurs in three different environments represented by two doublets. The first of them, assigned to combined M1 + M2 positions and the second one assigned to M3 site with parameters IS = 0.36 mm/s and QS = 2.07 mm/s is visible in the spectra up to 880°C. This doublet is characteristic of stilpnomelane and can be regarded as a "fingerprint" of this mineral. After heating at 200°C, the relative content of Fe2+, ΣFe2+/ΣFe, decreases to 0.22 what means a 50% decrease in comparison to the initial value observed in the untreated sample. At about 1000°C, complete breakdown of the stilpnomelane structure takes place and the Mössbauer spectrum consists of two sextets and two ferric doublets. Abnormally high content of Fe2+ in naturally weathered stilpnomelane (0.70) comparing to the untreated sample of stilpnomelane (0.45) indicates that the sample had to be subjected to hydrothermal processes operating locally. Almost the same contents of divalent iron and hyperfine parameters of Fe2+ and Fe3+ doublets in weathered stilpnomelane and associated chlorite suggest that the process of chlorite transformation into stilpnomelane seems to be very probable.},
note = {4},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
This paper reports the results of 57Fe Mössbauer study of stilpnomelane K0.6Fe6(Si8Al)(O;OH) 27·2H2O from Żółkiewka (Lower Silesia; Poland). Stilpnomelane in paragenesis with chlorite, tourmaline, claevelandite and zeolites has been found in granite pegmatites in quarries at Żółkiewka. The samples of naturally weathered stilpnomelane and chlorite from the same fragment of rock were also studied. The Mössbauer spectrum of an untreated sample could be fitted to two Fe2+ doublets and two Fe3+ doublets. The Fe2+ doublets have similar isomer shifts, but they distinctly differ in values of quadrupole splittings. Ferric iron, octahedrally coordinated occurs in three different environments represented by two doublets. The first of them, assigned to combined M1 + M2 positions and the second one assigned to M3 site with parameters IS = 0.36 mm/s and QS = 2.07 mm/s is visible in the spectra up to 880°C. This doublet is characteristic of stilpnomelane and can be regarded as a "fingerprint" of this mineral. After heating at 200°C, the relative content of Fe2+, ΣFe2+/ΣFe, decreases to 0.22 what means a 50% decrease in comparison to the initial value observed in the untreated sample. At about 1000°C, complete breakdown of the stilpnomelane structure takes place and the Mössbauer spectrum consists of two sextets and two ferric doublets. Abnormally high content of Fe2+ in naturally weathered stilpnomelane (0.70) comparing to the untreated sample of stilpnomelane (0.45) indicates that the sample had to be subjected to hydrothermal processes operating locally. Almost the same contents of divalent iron and hyperfine parameters of Fe2+ and Fe3+ doublets in weathered stilpnomelane and associated chlorite suggest that the process of chlorite transformation into stilpnomelane seems to be very probable.