The studied sediments of the Magierowa Member corespond to the Cenomanian/Turonian OAE 2. A better understanding of the genesis and palaeoenvironmental setting of this unit was achieved by means of geochemical indicators integrated with mineral composition. It suggests a strong influence of palaeoproductivity/redox cycles. The black shales are characterised by the enhanced accumulation and preservation of marine-derived organic matter. Lamination and enrich- ment of redox-sensitive elements (e.g., Ag, Cd, Mo, V) imply periodic prevalence of anoxic/euxinic conditions within the sediment (pore water) occasionally extending to the sediment/water interface. The bioturbated claystone intervals record periods of low productivity and development of more normal-marine conditions on the bottom. Furthermore, low Mn-contents, broad pyrite size-distribu- tion and presence of marine-origin organic matter suggest that an oxygen minimum zone (OMZ) must have existed within the water column during accumulation. The mineral assemblage of the Magierowa Mbr includes clay minerals, quartz, feldspar and iron minerals. Mineralogical data comparing with some gechemical ratios: Ti/Al, K/Al, Rb/Al suggest pelagic regime of deposition. Well-crystallised illite corresponding with high kerogen maturation and large iron mineral point to advanced diagenesis.
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The Cenomanian sequence of marls and marly shales interbedded by black shales (Jaworki Formation) from the Niedzica Succession was investigated. These organic carbon-rich horizons may correspond to the event of global anoxity OAE 1d. Major and trace element profiles mirror changing environments of deposition of black shales. In black shales, the content of SiO2, Al2O3, Fe2O3, K2O, TiO2, P2O5 increases at the expense of CaO. All samples are characterised as mixtures of terrigenous- detrital matter with varying amount of calcium carbonate. A good correlation between SiO2, Al2O3, K2O, TiO2, and the correlation with the minor elements Zr, Rb and Nb, point to the detrital origin of these elements. Detrital input was rather scarce. The high trace element/Al ratios in the black shales can be explained either by the adsorption onto organic matter or through the sulphides precipitation. Some black shale-samples are poorer in transitional metals. The studied sediments were deposited under oxic/suboxic conditions interrupted by irregular anoxic periods resulted from expansion of oxygen minimum zone (OMZ).
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Most of the craters on the Earth, produced by an impact of meteorite or other space object, have been masked by exogenous processes. The refore, indirect indicators of the impact such as shocked quartz have been recognized. The impact metamorphism is visibly recorded within quartz by distinctive microstructures. However, only the planar deformation features (PDF) are unquestionable evidences of impact. They should be investigated with particular accuracy because of similarity to endogenic planar microdeformations such as: growth features or metamorphic deformation lamellae. The K/Pg boundary interval from the Polish Outer Carpathians (Skole Unit, Husów. Thrust Sheet, Bąkowiec section) have been studied. This note presents difficulties in identifying shock features in quartz grains collected from turbiditic material.
The turbiditic to hemipelagic, fine-grained deposits of the Hradiště Formation (Hauterivian, 132 Ma) to the Lhoty Formation (Albian–Cenomanian, 99 Ma) in the western part of the Silesian Nappe (Polish Outer Car- pathians) were studied mineralogically and geochemically to determine if the main factors controlling the chemistry of the sedimentary material can be attributed to provenance, or to post-depositional processes. A high degree of weathering of the source rocks is indicated by the chemical index of alteration (CIA) that varies from 75.98 to 89.86, and Th/U ratios (~4 with outliers at 1.85 and >6). The cooccurrence of rounded and unabraded grains of zircon and rutile, the enrichment in Zr and Hf, as well as the high Zr/Sc ratios suggest that the Hradiště and Veřovice Formations contain recycled material. Plots of La/Th versus Hf and Th against Sc show that samples occur in the field of felsic and mixed felsic/basic sources. On a ternary La–Th–Sc diagram, all of the sediments studied are referable to the continental island-arc field. The European Plate, as an alimentary area, has a mosaic structure consisting of Cadomian and Variscan elements. The Proto-Silesian Ridge was detached from the continent, because of rifting. Therefore, it could have corresponded to a continental island arc. The concentrations of Fe and trace metals (e.g., Mo, Au, Cu) in the Veřovice Formation and silica and potassium additions to the Veřovice and Lhoty Formations, as well as the fractionation of REE, and Nb, Ta, Zr, Hf, and Y can be explained by the action of basinal brines. The fluids were of hydrothermal origin and/or were released, owing to the dewatering of clay minerals. Diagenetic processes could have exerted a greater influence on sedimentary rock chemistry than the provenance and sedimentary processes. A distinction between primary, terrigenous elements and those changed diagenetically is necessary for the reliable determination of provenance.
The chemical composition of the Cretaceous deposits of the Grajcarek thrust-sheets (Pieniny Klippen Belt, Poland) has been investigated to provide information on palaeoenvironment and provenance of pelagic and turbiditic particles. The material studied shows large variations in terrigenous and biogenic content. Phyllosilicates (mirrored in amounts of Al2O3, average 15 wt.%) and carbonates (6 wt.% of CaO) are common mineral components of the deposits excluding the Cenomanian radiolarian shales (CRS) that are enriched in silica "Immobile" elements may be accommodated by phyllosilicates and accessory minerals (i.e. zircon, xenotime, apatite and Ti-oxides). Heavy minerals are significant within the Szlachtowa Fm. High field strength elements (HFSE) in the Malinowa Fm. are housed in secondary apatite and Fe-oxides. Lithophile trace elements (LILE) concentrations in the material studied are lower/comparable to Post-Archean Australian Shale (PAAS). Ba concentration in the CRS probably reflects enhanced bioproductivity. Interaction between major oxides, distributions of "immobile' and lithophile elements suggest that variation in trace elements through the succession was mainly controlled by the terrigenous input. The material studied was sourced from intermediate to felsic rocks of the Czorsztyn (Oravic) Ridge. The Szlachtowa Fm. and CRS are more mature than others due to low contents of clay minerals. The Szlachtowa Fm. also contains recycled material. The CRS correspond to the oceanic anoxic event 2 (OAE 2) whereas the "Black Flysch" of the Szlachtowa and Opaleniec formations may be related to the Early Cretaceous OAE 1
In the Polish sector of the Magura Nappe have long been known and exploited carbonate mineral waters, saturated with carbon dioxide, known as the “shchava (szczawa)”. These waters occur mainly in the Krynica Subunit of the Magura Nappe, between the Dunajec and Poprad rivers, close to the Pieniny Klippen Belt (PKB). The origin of these waters is still not clear, this applies to both “volcanic” and “metamorphic” hypotheses. Bearing in mind the case found in the Szczawa tectonic window and our geological and geochemical studies we suggest that the origin of the carbon dioxide may be linked with the thermal/pressure alteration of organic matter of the Oligocene deposits from the Grybów Unit. These deposits, exposed in several tectonic windows of the Magura Nappe, are characterized by the presence of highly matured organic matter – the origin of the hydrocarbon accumulations. This is supported by the present-day state of organic geochemistry studies of the Carpathian oil and gas bed rocks. In our opinion origin of the carbon-dioxide was related to the southern, deep buried periphery of the Carpathian Oil and Gas Province. The present day distribution of the carbonated mineral water springs has been related to the post-orogenic uplift and erosion of the Outer (flysch) Carpathians.
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