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Minerały tarnobrzeskiego złoża siarki rodzimej

Parafiniuk Jan

Przegląd Geologiczny

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2023

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Vol. 71, nr 12

605--613

EN

The paper reviews the mineral composition of the native sulphur deposit inTarnobrzeg, recognized in the now-defunct open-pit Machów mine. Mineral specimens from this mine are known and valued worldwide. The mineral inventory of the deposit is relatively undiversified. Its main minerals are calcite and native sulphur formed from bacterial reduction of gypsum. They are accompanied by accessory ones: celestine and barite, very rarely strontianite andaragonite. Rare hauerite is also found in overburden clays. Calcite, sulphur, gypsum, celestine and barite form several age generations in the deposit and many interesting morphological forms from which its history can be reconstructed. Most of the spectacularly formed specimens of these minerals are related to the exposure of the deposit and its mining exploitation. The youngest generation of gypsum also documents the initiated process of degradation of the deposit.

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New data on celestine-rich salts in the Wieliczka salt deposits

Nowińska J.

Geology, Geophysics and Environment

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2017

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Vol. 43, no. 1

57--68

EN

Pale brownish celestine-rich salt rocks were found near the Franciuszek Müller gallery, in the chambers of the 3rd level in the Wieliczka Salt Mine. The complex of rock salts subjected to exploration occurred within a large seam approximately 15 m thick. Detailed research revealed that the salt has the form of a block incorporated within the gray salts body and being similar to other blocks of green salts, well known in the upper part of the deposit. A characteristic petrographical feature of the pale brown rock salt owed to the presence of celestine (SrSO 4 ). That strontium mineral was re-examined, using X-ray powder data, and scanning microscope observations, with EDS analysis. The investigated rock salts exhibited a mineral association of halite (main component), anhydrite, celestine, calcite, gypsum, clay materials, iron compounds and a small amount of bitumen. Interrigenous sediments and the insoluble part of salt occurred higher content of strontium that in halite. Celestine crystals were observed in two forms: elongated platy crystals, forming fan-shaped aggregates and granular aggregates, strongly associated with anhydrite. On carbonate and sulphate strontium usually appearing as needle shaped aggregates of celestine. No barium minerals were observed. The development and paragenesis of celestine suggested a post-sedimentary origin of these rocks that ought to be connected with diagenetic processes. An important observation that confirmed that thesis was the transformation of fine crystalline anhydrite into platy crystals, recrystallization and primary accumulation of strontium, as a result of evaporation processes.

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Stable isotopic and mineralogical investigations of an arid Quaternary lacustrine palaeoenvironment, Western Qaidam, China

Bojar A. V., Rieser A., Neubauer F., Bojar H. P., Genser J., Liu Y., Ge X. H.

Geological Quarterly

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2005

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Vol. 49, No. 2

173-184

EN

Stable isotope analyses on carbonates from lake evaporites collected from the non-marine western Qaidam basin yield a positive excursion from Pliocene to Quaternary times. At Dafeng Shan, the Quaternary sequences are composed of alternating layers of celestine/dolomite and aragonite/calcite/barite with distinct isotopic compositions. The sequence described at Dafeng Shan formed in a low energy, hypersaline lacustrine environment as indicated by the microstructures and evaporitic minerals as well as by the absence of lithoclasts. The peloids, ooids and oncoids described are related to microbialactivities in saline lake. The oxygen isotopic composition of the carbonates vary between +34.4 and +39.8‰ (SMOW), representing the heaviest values measured until now. The δ18 O and the δ34 S isotopic composition of the celestine range between 20.1 to 22.3‰ (SMOW) and +19 to +22‰ (CDT) respectively, suggesting sulfur recycling via sulfide oxidation. The carbon isotopic compositions of the carbonates show a large negative excursion of up to -30‰. The microstructures, mineralogy and isotopic compositions as well as the geological context suggest oxidation of methane from a deep source.