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Geochemical and mineralogical characteristics of calamines from the Olkusz zinc and lead ore district (South Poland)

Swęd Maciej Krzysztof, Duczmal-Czernikiewicz Agata

Geological Quarterly

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2019

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Vol. 63, No. 4

699--710

EN

The mineralogical and geochemical characteristics of calamines developed from chemical weathering within two different tectonic settings (tectonic horst and graben) are described. Calamines collected from the Olkusz-Pomorzany and the Bolesław zinc and lead mines were analysed geochemically by means of EMP and SEM-EDS and their mineralogical composition was identified by using reflected light microscopy and XRD analysis. The calamines from the Olkusz-Pomorzany mine are composed of marcasite, galena, cerussite, sphalerite, hemimorphite, smithsonite and goethite. Hemimorphite prevails over smithsonite and occurs in the vicinity of primary sulphides. The mineralogical composition of the calamines from the Bolesław area is less diverse. These are primarily composed of goethite and smithsonite, with a minor content of marcasite and remnant sphalerite. The mineral composition of weathering sites in the Olkusz-Pomorzany and Bolesław areas may reflect different geochemical conditions (from slightly acidic to alkaline pH values, from lower to higher CO2 partial pressure and solutions of different silica saturation) that could have changed over time. The mineralogical compositions of the calamines differ quantitatively and this could reflect the tectonic setting of the primary ore affecting the rate of chemical weathering.

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Zmienność wskaźników wietrzenia współczesnych osadów Odry i jej dopływów

Bojakowska I., Nadłonek W.

Systemy Wspomagania w Inżynierii Produkcji

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2016

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z. 5 (17)

48--60

PL

Wskaźniki wietrzenia chemicznego są powszechnie stosowane do charakterystyki profili wietrzeniowych i określania stopnia procesu wietrzenia. Ich wartości pozwalają na wskazanie składu niezwietrzałej skały macierzystej. Wykorzystując wyniki badań osadów zlewni Odry i Warty przeprowadzono próbę określenia zmienności wskaźników wietrzenia na tym obszarze kraju. Wśród stosowanych wskaźników największą rolę mają wietrzeniowy wskaźnik Parkera (WIP) i chemiczny wskaźnik przemian (CIA), zatem im poświęcono najwięcej uwagi. W celu lepszego odzwierciedlenia intensywności wietrzenia stosowano dodatkowe wskaźniki, wrażliwe na najmniejsze zmiany geochemiczne. Obliczano wskaźnik Vogt’a (V), wskaźnik wietrzenia chemicznego Harnois’a (CIW) i wskaźnik przemian plagioklazów (PIA). Wyniki badań pozwoliły na ocenę intensywności wietrzenia na całym obszarze badawczym, a także na wskazanie czynników odpowiadających za jego przebieg. Na wartość wskaźników wietrzenia wpływają: litologia, klimat, wielkość spływu powierzchniowego i morfologia terenu.

EN

Chemical weathering indices are commonly used for characterizing weathering profiles and evaluating degree of weathering process. Their values allow to point at nonweathered source rock composition. Using study results of Odra and Warta drainage basin sediments, there was made a try to define variability of chemical indices in this country area. Among applied indices the most important role have Weathering Index of Parker (WIP) and Chemical Index of Alteration (CIA), thus them was given the most attention to. In order to better reflecting the intensity of weathering there were used additional indices, sensitive to the slightest geochemical changes. Vogt’s Residual Index (V), Chemical Index of Weathering (CIW) and Plagioclase Index of Alteration (PIA) were calculated. Study results let to evaluation the weathering intensity in the all study area and to indicate factors, which are in charge of this process. Lithology, climate, flow magnitude and region morphology have an influence on the values of weathering indices.

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Chemical weathering of talus slopes: the example of slopes in the Brattegg Valley, Sw Spitbergen

Senderak K., Wąsowski M.

Studia Geomorphologica Carpatho-Balcanica

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2016

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Vol. 50

105—122

EN

This paper presents the results of hydrogeochemical surveys carried out in the non-glaciated part of the Brattegg Valley near Hornsund Fjord (SW Spitsbergen). The aim of the study was to indicate places in periglacial zone with the greatest intensity of chemical weathering. The valley was divided into five zones where 11 observation sites were selected. The physico-chemical parameters of water were measured in situ. Water chemical composition was defined using ion chromatograph and mineral composition was obtained based on X-ray diffraction analysis. The results of the study show that in the studied valley, talus slopes are the most dynamic environment of the periglacial zone and are typified by the greatest intensity of chemical weathering.

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Mineral assemblages as a record of the evolutionary history of the Pepper Mts. Shale Formation (the Holy Cross Mts.)

Naglik B., Natkaniec-Nowak L., Heflik W.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 2

161--173

EN

The Pepper Mts. Shale Formation, consisting of: clayey shales, mudstones and sandstones, as one of the oldest unit of the Holy Cross Mts., was subjected to mineralogical and petrographical studies. In order to reconstruct the geological history of the succession, mineral assemblages were characterized from the genetic point of view. Pyrite and goethite taking a form of bacterial-cell pseudomorphoses, crystallized during sedimentation and/or diagenesis, while quartz, kaolinite, goethite and chlorite prove subsequent alteration due to the hydrothermal fluid circulation. Secondary sulphates occurring on the pyrite-bearing rock outcrops mark the way of weathering processes. According to the presented results, Cambrian sediments were affected by hot fluids, which caused mineral recomposition and maturing of organic matter. Under the hypergenic conditions sulphate crust precipitate with pickeringite [MgAl 2 (SO 4 ) 4 ∙ 22H 2 O], as a dominant phase accompanied by alunogen [A l 2 (SO 4 ) 3 ∙ 17H 2 O] and small amount of epsomite [MgSO 4 ∙ 7H 2 O].

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Transport conditions of mountain-surging glaciers as recorded in the micromorphology of quartz grains (Medvezhiy Glacier, West Pamir)

Muzińska A.

Geologos

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2015

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Vol. 21, No. 2

127--138

EN

In order to reproduce the conditions under which sediments were transported in surging glaciers, samples were taken from the margin and foreland of the surge Medvezhiy Glacier situated in West Pamir (Tajikistan). They were subjected to an analysis of rounding and frosting of quartz sand grains (0.8–1.0 mm) and of grain surface micromorphology under scanning electron microscope (SEM). Results obtained showed intense chemical weathering occurred in the majority of quartz grain surfaces, marked in the form of etching and precipitation. Frequencies of microstructures of glacial origin were low; individual microstructures were visible on single grains. A predominance of the crushing process over abrasion in transformation of quartz grains was noted. The commonest microstructures connected with a surge-glacier environment were large and small conchoidal fractures. However, grains with primary features not connected with a glacial environment were equally common. The majority of the grains examined showed features of multiple cycles of mechanical and chemical weathering forming a microtexture under various conditions (overprinting). Common features of grains from surging glaciers are also breakage blocks of >10μm, which depend of the phase of separation of the grain from the rock or on thermal changes in the glacier’s foreland.

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Chemical weathering on the glacial foreland of Storbreen, Jotunheimen Mountains, Norway

Thorn C. E., Darmody R. G., Allen C. E., Campbell S. W.

Landform Analysis

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2007

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Vol. 5

87--88