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The assemblages of transparent heavy minerals in Quaternary sediments of the Kielce-Łagów Valley (Holy Cross Mountains, Poland)

Ludwikowska-Kędzia Małgorzata

Geologos

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2013

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Vol. 19, No. 1-2

95--129

EN

The composition of the transparent heavy-mineral assemblages (0.25-0.1 mm) in Quaternary slope, karst, glacial, fluvioglacial and fluvial deposits with different parent material was investigated in the Kielce-Łagów Valley (the central part of the Palaeozoic core of the Holy Cross Mountains). For the purpose, 93 samples of mostly sandy sediments were examined. Some marker and some supporting minerals can be distinguished. Slope and karst deposits are dominated by the abrasion-resistant minerals zircon, tourmaline, staurolite and rutile. This assemblage points at a source consisting of strongly weathered pre-Quaternary bedrock. Glacial and fluvioglacial deposits are dominated by medium-resistant and non-resistant minerals (garnet, amphibole, pyroxene and biotite). The two types of parent material of the heavy minerals are typical of the Quaternary deposits in the Polish uplands. The two sources are most clear in the younger (Vistulian and Holocene), mostly fluvial sediments. The results of the analysis imply that the impact of Pleistocene glaciers on the central part of the Holy Cross Mountains was neither large enough to hide the local mineralogical background, nor sufficient to dominate over the main processes transforming the mineral composition under the variable climatic conditions of the Quaternary, including aeolian processes and chemical weathering.

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Heavy-mineral assemblages from fluvial Pleniglacial deposits of the Piotrków Plateau and the Holy Cross Mountains - a comparative study

Wachecka-Kotkowska Lucyna, Ludwikowska-Kędzia Małgorzata

Geologos

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2013

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Vol. 19, No. 1-2

131--146

EN

The heavy-mineral assemblages of Pleniglacial fluvial sediments were analysed for two river valleys, viz. the Luciąża River (at Kłudzice Nowe) and the Belnianka River (at Słopiec). These sites, on the Piotrków Plateau and in the Holy Cross Mountains respectively, are located in different morphogenetic zones of Poland that were affected to different degrees by the Middle Polish ice sheets. The study was aimed at determining the kind of processes that modified the heavy-mineral assemblages in the two fluvial sediments, at reconstructing the conditions under which these processes took place, and in how far these processes caused changes in the assemblages. The heavy-mineral associations of the parent material was taken as a starting point; this parent material were the sediments left by the Odranian glaciation (Warta stadial = Late Saalian). It was found that heavy-mineral assemblages in the Luciąża valley deposits are varied, particularly if compared with other fluvioglacial Quaternary deposits from the Polish lowlands, with a dominance of garnet. In the fluvial deposits of the Belnianka valley, zircon, staurolite and tourmaline dominate, with minor amounts of amphibole, pyroxene, biotite and garnet. This suggests that the deposits were subject to intensive and/or persistent chemical weathering and underwent several sedimentation/erosion cycles under periglacial conditions. In both valleys chemical weathering and aeolian processes were the main factors that modified the assemblages of the transparent heavy minerals; these processes were largely controlled by the climatic changes during the Pleistocene.

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Heavy-mineral analysis in Polish investigations of Quaternary deposits: a review

Marcinkowski Bogusław, Mycielska-Dowgiałło Elżbieta

Geologos

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2013

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Vol. 19, No. 1-2

5--23

EN

The composition of heavy-mineral assemblages is one of the main textural features of sediments because they can have significant value for the interpretation of, among others, their depositional environment, their depositional processes, and their stratigraphic position. Distinctive features of heavy minerals include their resistance to chemical weathering and mechanical abrasion, their habit, and their density. These parameters are the most widely used in the heavy-mineral research of Quaternary deposits in Poland, as well as in such research in other countries conducted by Polish scientists. Several other heavy-mineral parameters can also be used in various types of interpretation. It is discussed whether heavy-mineral analysis is decisive in the evaluation of deposits or whether it plays mainly a role that may support evidence obtained by other types of analysis. The attention is mainly devoted to transparent heavy minerals; the significance of opaque heavy minerals for interpretational purposes is only mentioned.

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Heavy-mineral analysis as a tool in tephrochronology, with an example from the La Sal Mountains, Utah, U.S.A.

Kleber Arno

Geologos

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2013

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Vol. 19, No. 1-2

87--94

EN

An essentially pure tephra layer on a steep slope in the La Sal Mountains, Utah, U.S.A., is correlated with the 1.65 Ma old Guaje Tephra derived from the Jemez Mountains, New Mexico, U.S.A. The heavy-mineral contents and glass shards in sediments beneath the La Sal tephra layer indicate that tephra constituents are contained in deposits considerably older than the pure layer. This suggests that tephra material may become reworked while retaining its pure character, possibly due to laminar transport or to dislocation in a frozen condition. This raises the need to handle tephrochronological findings with great care.

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Osady preglacjalne południowej części Niziny Mazowieckiej w świetle wyników analizy minerałów ciężkich

Bujak Ł.

Biuletyn Państwowego Instytutu Geologicznego

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2010

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nr 438

19--31

PL

Prezentowane wyniki analiz minerałów ciężkich dotyczą osadów preglacjalnych pochodzących z 3 odsłonięć położonych na Równinie Kozienickiej (Brzóza k. Kozienic, Januszno k. Pionek, Stanisławice k. Kozienic) oraz wiercenia Niwa Babicka wykonanego w ramach prac nad arkuszem Żelechów Szczegółowej mapy geologicznej Polski w skali 1:50 000. Uzyskane wyniki pozwoliły podzielić badane osady na dwa typy. Pierwszy charakteryzuje wysoka zawartość granatów oraz minerałów odpornych na wietrzenie chemiczne i mechaniczne (turmaliny, cyrkony, staurolity, dysteny oraz rutyle). Takie spektrum minerałów stwierdzono w stanowiskach położonych na zachód od współczesnej doliny Wisły (Brzóza, Januszno, Stanisławice). Jednakże pomiędzy tymi osadami obserwuje się różnicę polegającą na dominacji granatu nad minerałami odpornymi (Januszno), bądź minerałów odpornych nad granatami (Brzóza, Stanisławice). Odmienny zespół minerałów ciężkich stwierdzono w osadach preglacjalnych z Niwy Babickiej. Charakteryzują się one nawet kilkudziesięcioprocentowym udziałem chlorytów, granatów oraz turmalinów. Powyższe wyniki pokazują, że utworami źródłowymi dla osadów preglacjalnych południowej części Niziny Mazowieckiej były różnowiekowe pokrywy zwietrzelinowe północnego obrzeżenia Gór Świętokrzyskich i Wyżyny Lubelskiej, poddawane intensywnym procesom wietrzenia chemicznego. Różnice w zespołach minerałów ciężkich mogą wynikać z kierunku transportu (stożki Prawisły i Prawieprza) oraz facji osadów: korytowej lub wezbraniowej.

EN

Analyses of heavy minerals were performed on samples taken from Preglacial deposits from three sites situated in the Kozienice Plain (Brzóza near Kozienice, Januszno near Pionki, Stanisławice near Kozienice) and from the Niwa Babicka borehole near Ryki, drilled for the need of the Detailed Geological Map of Poland at a scale of 1:50,000, Żelechów sheet. Results of the analyses allow categorising the deposits into two types. The first one, recognized in Brzóza, Januszno and Stanisławice, contains large amounts of garnets and minerals resistant to chemical and mechanical weathering: tourmalines, zircons, staurolites, disthenes and rutiles. However, these deposits are differentiated regarding the contents of dominant heavy minerals. In Januszno, garnets predominate over resistant minerals. In Brzóza and Stanisławice, resistant minerals outnumber garnets. The second type of Preglacial deposits was recognized in the Niwa Babicka borehole. These deposits contain several dozens percents of chlorites, garnets and tourmalines. Results of the analyses allow inferring that the sources of Preglacial deposits found in the southern Mazovian Lowland were weathering mantles of various ages developed along the northern border of the Holy Cross Mountains and Lublin Upland, where very strong chemical weathering took place. The differences in the heavy mineral content can result from different transport directions (alluvial fans of the pra-Vistula or pra-Wieprz rivers) and differences in deposit (channel or flood) facies.

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OSL dates and heavy mineral analysis of upper quaternary sediments from the valleys of the Ér and Berettyó rivers

Thamó-Bozsó E., Magyari Á., Nagy A., Unger Z., Kercsmár Z.

Geochronometria

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2007

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Vol. 28

17-23

EN

The study of the evolution of the river network in the Great Hungarian Plain has been based on sedimentological, neotectonical, morphological investigations, heavy mineral analysis and complementary OSL dating. The study area extends from the Körös sub-basin into the Ér and Berettyó river valleys which are situated northeast from the subsiding basin and northwest from the uplifting Apuseni Mountains. The OSL ages provide evidence that a large river run in the Ér-valley at least from 46 ±4 to 39 ±4 ka. It deposited garnet and magnetite-ilmenite-rich sediments, similar to the recent Berettyó, Ér and Sebes-Körös rivers and less intensive the modern Tisza river. These sediments originated from the nearly located metamorphic and Neogene volcanic rocks and contain some reworked older clastic sedimentary rocks from the northern part of the Apuseni Mountains. These OSL ages fit the active tectonic phase of the Érmellék depression. Loess is 49-47, 44, 39 and 25 ka old and aeolian sands 10 to 9 ka were dated. Their heavy mineral composition and that of fluvial sands is similar.