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Abstract

Productacean brachiopod assemblages are described from 10 taphocoenoses from various facies of the Upper Permian Kapp Starostin Formation in Spitsbergen. Time and space relationships among the investigated phena are based upon a previously established chronostratigraphic correlation of the strata. 15 productacean species are distinguished, based upon analysis of their morphology and ecology. Their paleontological descriptions take into account the ranges of their ecophenotypic variation. Shells adapted to three modes of life are recognized among the considered Productacea: (1) forms stabilizing within loose bottom sediments, (2) forms floating at the surface of soft substrates, and (3) forms living just below the surface of quaggy substrates. Distribution of the productacean assemblages in the Kapp Starostin Formation is analyzed within the framework of a reconstruction of the history of the Permian sea in this area. The main ecological controls upon this distribution include stratification of the water, substrate suitability for settlement, and coastal influences on the marine environment. Because of their spatially limited distribution and unrecognized evolution within the considered time interval, the investigated brachiopods cannot be employed for biochronostratigraphy.
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Abstract

The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians recorded provide a means of correlation with zonation schemes based on Unitary Associations defined for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.
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Abstract

GPR method is perfectly suited for recognizing of sedimentary facies diversity in shallowly occurring sediments if there is a contrast of electrical properties between and/or within each layer. The article deals with the issue of the correlation between GPR surveys results and sedimentological analyses. As a result of this correlation a conceptual model of depositional systems of studied areas was developed. Studies were performed in two areas located in central Poland, where glacial deposits formed in the Middle Polish (Saalian) Glaciation are present. The study was based on 49 sediment samples and 21 GPR profiles. Analyses of lithofacies as well as granulometric and mineralogical composition of deposits of collected samples were carried out, showing the diversity of glacial deposits in both study sites. During GPR measurements shielded antenna with a frequency of 500 MHz was used which allowed high-resolution mapping of the internal structure of deposits and to identify four characteristic radar facies. Correlation of GPR profiles with point, one-dimensional sedimentological studies allowed the unambiguous interpretation of the GPR image and draw conclusions about the formation environment of individual units. Geophysical and sedimentological data obtained during study provide a new and detailed insight into selected glacial deposits in central Poland.
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Abstract

An accumulation of glacial sediments is located near Písečná village in the depression between the Sokol Ridge and Zlaté Hory Highlands NNE of Jeseník town (Eastern Sudetes). The accumulation lies at the lateral side of the mountain valley of the Bělá River and fills a preglacial palaeovalley of this river. Research combining facies analysis of outcrops, ground penetrating radar survey, interpretation drilling survey, and modelling of the preglacial relief was undertaken at the site. According to the results obtained, the upper part of the sedimentary accumulation represents a coarse-grained terminoglacial glaciofluvial delta of the Gilbert type. The development of the accumulation has dominantly been driven by the preglacial morphology. Facies typical for foresets of coarse-grained deltas represented mainly by high-density flows, cohesionless debris flows, debris falls and less common low-density flows were found in the outcrops. The delta near Písečná prograded into a lake dammed by the ice-sheet front in the north. The lake was bounded by the slopes of Sokol Ridge, Zlaté Hory Highlands and Góry Parkowe on other sides. The lake level reached an altitude of up to 430 m a.s.l., as the coarse-grained delta plain base lies at this level.
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