Abstract
Rb-Sr data were obtained for different Lower Cambrian rocks from boreholes Bel’sk and Zhigalovo drilled in the Irkutsk amphitheater. Shales in the lower part and insoluble residue of marls throughout the entire (up to 2 km thick) sequence define the first transformation stage of silicate rocks dated at 580 Ma with a large uncertainty. Sulfate and carbonate rocks are the main Sr carriers in the Lower Cambrian rocks. Owing to a negligible amount of silicate impurities in them, the input of radiogenic Sr exerted no significant influence on the Rb-Sr isotope system. However, almost all carbonate and sulfate rocks studied are contaminated by radiogenic Sr relative to its initial isotopic composition in the sedimentation basin. Hence, the rocks experienced epigenetic (probably, repeated) recrystallization and one or several stages of dissolution.
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Bujakaite, M.I., Vinogradov, V.I., and Sokolov, D.D., Rb-Sr Dating of Sedimentary Rocks: Approaches and Data Processing, Byull. Mosk. O-va Ispyt. Prir., Otd. Geol., 2005, vol. 80, no. 3, pp. 62–68.
Faure, G., Principles of Isotopic Geology, New York: Wiley, 1986. Translated under the title Osnovy izotopnoi geologii, Moscow: Mir, 1989.
Jacobsen, S.B. and Kaufman, A.J., The Sr, C, and O Isotopic Evolution of Neoproterozoic Seawater, Chem. Geol., 1999, vol. 161, pp. 35–57.
Lysak, S.V. and Zorin, Yu.A., Geothermal Field of the Baikal Rift Zone, Moscow: Nauka, 1976.
Palmer, M.R. and Edmond, J.M., The Strontium Isotope Budget of Modern Ocean, Earth. Planet. Sci. Lett., 1989, vol. 92, pp. 11–26.
Pinneker, E.V., Brines of the Angara-Lena Artesian Basin, Moscow: Nauka, 1966.
Pisarchik, Ya.K., Lithology and Facies of Lower-Middle Cambrian Rocks in the Irkutsk Amphitheater, Leningrad: Gos. Nauchn.-Tekhn. Inst. Neft. Gorno-Topliv. Literatury, 1963.
Pisarchik, Ya.K., Minaeva, M.A., and Rusetskaya, G.A., Paleogeography of the Siberian Craton, Leningrad: Nedra, 1975.
Rassmussen, B., Radiometric Dating of Sedimentary Rocks: The Application of Diagenetic Xenotime Geochronology, Earth Sci. Rev., 2005, vol. 68, pp. 197–243.
Semikhatov, M.A., Refinement of Estimates of the Isotopic Age of Lower Boundaries of the Upper Riphean, Vendian, Upper Vendian, and Cambrian: Supplement 4, in Supplements to the Stratigraphic Code of Russia, St. Petersburg: Vseross. Geol. Inst., 2000, pp. 95–107.
Sokolov, D.D. and Bujakaite, M.I., Some Specific Features of the Application of the Least-Squares Method in Rb-Sr Geochronometry, in Evolyutsiya sistemy kora-mantiya (Evolution of the Crust-Mantle System), Moskow: Nauka, 1986, pp. 207–217.
Veizer, J., Davin, A., Karem, A., et al., 87Sr/86Sr, δ13C, and δ18O Evolution of Phanerozoic Seawater, Chem. Geol., 1999, vol. 161, pp. 59–88.
Vinogradov, V.I. and Chernyshov, I.V., Standard Samples and Check Tests for Isotopic Geochronology, Izv. Akad. Nauk SSSR, Ser. Geol., 1987, no. 11, pp. 71–78.
Vinogradov, V.I., Belenitskaya, G.A., Bujakaite, M.I., et al., Isotopic Signatures of Deposition and Transformation of Lower Cambrian Saliferous Rocks in the Irkutsk Amphitheater: Communication 1. Sulfur Isotopic Composition, Litol. Polezn. Iscop., 2006, vol. 41, no. 1, pp. 96–110.
Vinogradov, V.I., Bujakaite, M.I., Murav’ev, V.I., et al., Isotopic Evedence of the Paleozoic Stage of Epigenetic Transformation of Vendian Sediments of the Russian Platform, Litol. Polezn. Iskop., 2002, vol. 37, no. 5, pp. 525–534 [Litol. Miner. Resour. (Engl. Transl.), 2002, vol. 37, no. 5, pp. 454–461].
Walter, M.R., Veevers, J.J., Calver, C.R., et al., Dating the 840–544 Ma Neoproterozoic Interval by Isotopes of Strontium, Carbon, and Sulfur in Seawater, and Some Interpretative Models, Precambrian Res., 2000, vol. 100, pp. 371–433.
Wolf, K.H., Chilingar, G.V., and Biles, F.U., Elementary Composition of Carbonate Organic Remains, Minerals, and Sediments, in Carbonate Rocks: Origin, Occurrence, and Classification, Chilingar, G., Fairbridge, R., Bissel, J., et al., Eds., Amsterdam: Elsevier, vol. 2, 1968. Translated under the title Karbonatnye porody, Moscow: Mir, 1971, vol. 2, pp. 9–111.
York, D., Least-Squares Fitting of a Straight Line, Canad. J. Phys., 1966, vol. 44, pp. 1079–1086.
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Original Russian Text © V.I. Vinogradov, G.A. Belenitskaya, M.I. Bujakaite, V.N. Kuleshov, M.A. Minaeva, B.G. Pokrovskii, 2006, published in Litologiya i Poleznye Iskopaemye, 2006, No. 2, pp. 183–192.
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Vinogradov, V.I., Belenitskaya, G.A., Bujakaite, M.I. et al. Isotopic signatures of deposition and transformation of Lower Cambrian saliferous rocks in the Irkutsk amphitheater: Communication 2. Strontium isotopic composition. Lithol Miner Resour 41, 165–173 (2006). https://doi.org/10.1134/S0024490206020052
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DOI: https://doi.org/10.1134/S0024490206020052