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Masywna mineralizacja siarczkami miedzi w dolomitach z kopalni Lubin (monoklina przedsudecka)

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Król P. , Sawłowicz Z.

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tom nr 468

29--47

PL

Masywna mineralizacja kruszcowa występująca w dolomitach z przedsudeckiego złoża miedzi została opisana szczegółowo po raz pierwszy. W badaniach trzech profili z kopalni Lubin wykorzystano metody mikroskopii optycznej i elektronowej mikroskopii skanningowej z analizą chemiczną w mikroobszarze, katodoluminescencji oraz dyfraktometrii rentgenowskiej. Mineralizacja masywna, składająca się głównie z chalkozynu z domieszką kalcytu, występuje w skałach węglanowych (dolomitach i dedolomitach) w formie poziomej pseudożyły, podścielonej lokalnie brekcją ilasto-węglanową i łupkiem. Niżejległe dolomity uległy częściowej kalcytyzacji (dedolomityzacji). Różne generacje kalcytu szczegółowo scharakteryzowano. Zaproponowano model powstania mineralizacji masywnej. Początkowo mezotektoniczne ruchy międzywarstwowe spowodowały powstanie rozwarstwień i brekcji. Następnie proces kalcytyzacji doprowadził do dedolomityzacji oraz częściowego wypełnienia spękania. Całkowite wypełnienie spękań oraz częściowe zastąpienie w nich kalcytu oraz skał otaczających nastąpiły w wyniku działalności roztworów kruszconośnych.

EN

Massive ore mineralization in dolomites is described for the first time from the Fore-Sudetic copper deposits. Three cross- -sections from the Lubin Mine were studied using polarized optical (PLM) and scanning electron (SEM-EDS) microscopy, also cathodoluminescence (CL) and XRD. Massive mineralization, composed mainly of chalcocite with calcite admixture, occurs in dolomites as horizontal pseudovein, locally underlain by clay-carbonate breccia and shale. Underlying dolomites were partly calcitized (dedolomitized). Various calcite generations are characterized in detail. A model of the formation of massive mineralization is proposed. Mesotectonic intralayer movements caused the cracking of dolomite layers and the formation of breccia. Calcitization led to both dedolomitization and the partial infilling of cracks. Mineralizing fluids infilled the cracks completely, partly replacing calcite and adjacent rocks.

2

Pyrite framboids in pyritized Radiolarian skeletons (Mid-Cretaceous of the Pieniny Klippen Belt, Western Carpathians, Poland)

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Szczepanik P. , Sawłowicz Z. , Bąk M.

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tom Vol. 74, No 1

35--41

EN

Well preserved pyritized radiolarian skeletons have been found within the grey-green Mid-Cretaceous (Upper Cenomanian) shales in the Pieniny Klippen Belt (Carpathians, Poland). The skeletons contain numerous pyrite framboids in different positions, in channels and inside the abdomen of cryptothoracic forms, but their genetic context is not known. They were formed as a result of the reaction between dissolved iron and sulphide originated from the bacterial sulphate reduction. Two sources of organic matter, "post mortem" in situ decaying organic matter of radiolaria and disseminated organic matter from the surrounding sediment could be available for this process. Pyrite found in the radiolarians probably originates from different processes. It is suggested that pyritization of the radiolarian skeletons took place in the water column whereas pyrite framboids in the skeleton's free spaces could have been formed later during the diagenesis of the sediment. However, their simultaneous formation in the water column or in the sediment cannot be excluded.

3

Mineralization of teeth and bones of the cave bear (Ursus spelaeus) from the Biśnik Cave, Southern Poland

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Rogóż A. , Sawłowicz Z. , Socha P. , Stefaniak K.

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tom Vol. 40, iss. 1/4

65--84

EN

The studied bones and teeth of the cave bear (Ursus spelaeus) come from the Biśnik Cave, located in the Częstochowa Upland (Southern Poland). The specimens originate from different geological layers formed since the Odra Glaciation (250–270 thousand years BP). The fossilized bones and teeth were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, FTIR spectroscopy, and INAA. They are built of recrystallized carbonate-rich apatite-(CaOH) and/or apatite-(CaOH). The teeth additionally contain some apatite-(CaF). The lack of collagen and minor REE contents suggest rapid burial and collagen decay in the early stage of diagenesis. The bones and teeth have only limited mineral infillings. In some teeth, Mn-Fe (hydroxy)oxides were found in the dentine canaliculi and in bones, some osteocyte lacunae contain Fe (hydroxy)oxides with admixture of Mn. In one bone specimen, calcite infillings are present in Haversian canals. The infillings formed during later stages of diagenesis and were succeeded by non-filled cracks.