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Strontium isotope composition of Badenian (Middle Miocene) Ca-sulphate deposits in West Ukraine: a preliminary study m

Peryt T. M., Hryniv S., Anczkiewicz R.

Geological Quarterly

2010

Vol. 54, No 4

465-476

Strontium isotope compositions have been measured in six primary gypsum samples from the most marginal part of the Badenian evaporite succession in the Ukrainian Carpathian Foredeep Basin (Mamalyha quarry section) and in two anhydrite samples from the basin-centre halite zone of the Ukrainian Carpathian Foredeep, aimed determining the origin of brines from which these sulphates were precipitated. The strontium isotope ratios (87868868761887 6878786

Isotopic composition of dolomite associated with Middle Miocene Badenian anhydrites in the Carpathian Foredeep Basin of SE Poland

Jasionowski M., Peryt T.M.

Geological Quarterly

2010

Vol. 54, No 4

533-548

Dolomite is a quite common, although usually minor, constituent of the Badenian sulphate deposits of the Carpathian Foredeep Basin. In the autochthonous member of the Wola Różaniecka 7 borehole (SE Poland) which contains well preserved, large anhydritic pseudo-morphs after selenitic gypsum, dolomite constitutes up to 75% of the rock volume, the rest being anhydrite. Dolomites mostly show peloidal clotted microfabrics typical of microbialites and are interpreted as products of microbially induced precipitation and/or dolomitisation at temperatures around 40°C (as interpreted from the d18131813

Strontium isotopes in the Zechstein (Upper Permian) anhydrites of Poland: evidence of varied meteoric contributions to marine brines

Denison R. E., Peryt T. M.

Geological Quarterly

2009

Vol. 53, No 2

159-166

Strontium isotope ratios have been determined on 74 anhydrite samples from seven borehole cores in the Polish Zechstein. Five of the borehole cores are located in the basin and isotope results from these samples show a nearly pure marine signal. Results from one borehole core, located near the Zechstein coastline that migrated through time, record a stronger, in consistent influence of continental strontium to a marine base. Intermittent meteoric influence is recorded in anhydrites from other borehole cores close to the carbonate platform that was emergent during the anhydrite deposition. Consistency of isotope values indicates a marine signal and there is a narrow range in consistent values from 87Sr/86Sr near deltasw –215 (0.70702) for the oldest anhydrites and near deltasw –205 (0.70712) for the youngest an hydrites. Comparison with a sea water 87Sr/86Sr curve based on samples in West Texas and a Permian-Triassic boundary value from China shows that the Polish Zechstein in these seven boreholes is latest Permian in age and major deposition represents a short time interval (~2 million years). Strontium isotope ratios reported by other workers indicate some of the younger Zechstein elsewhere indicate even greater continental influence is in agreement with the interpreted sedimentological set ing for those anhydrites.