Nauki Ścisłe i Nauki o Ziemi

Acta Geologica Polonica

Zawartość

Acta Geologica Polonica | 2020 | vol. 70 | No 1 |

Abstrakt

The damage zones of exhumed strike-slip faults dissecting Jurassic carbonates in the south-western part of the Late Palaeozoic Holy Cross Mountains Fold Belt reveal second-order faults and fractures infilled with syntectonic calcite. The subsequent development of a structural pattern of microscopic fault-related structures and calcite infillings reflects the activity of strike-slip faults that began in the Late Cretaceous (Late Maastrichtian) and lasted until the early Miocene (Langhian). The fabric of the syntectonic veins provides insights into the evolution of the permeable fault-related structures that were the main pathways for fluid flow during fault activity. Microstructural study of calcite veins coupled with stable isotope and fluid inclusion data indicates that calcite precipitated primarily in a rock-buffered system related to strike-slip fault movement, and secondarily in a partly open system related to the local activity of the releasing Chmielnik stepover or the uplift of the area. The presence of meteoric fluids descending from the surface into damage zones suggest that the strike-slip faulting might have taken place in a nonmarine, continental environment.

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Autorzy i Afiliacje

Barbara Rybak-Ostrowska
Andrzej Konon
Vratislav Hurai
Maciej Bojanowski
Agnieszka Konon
Michał Wyglądała

Abstrakt

The Neogene basaltoid intrusions found in the S-7 borehole in the Sumina area (USCB) caused transformations of the adjacent Carboniferous rocks. The mineral and chemical compositions of the basaltoides are similar to those of the Lower Silesian basaltoides. The transformations that took place in the vicinity of the intrusion were manifested in the formation of natural coke, the secondary mineralization of these rocks (calcite, chlorite, zeolites and barite) and in the specific distribution of rare earths (REY). Among REY, the light elements (LREY) had the highest share, while the heavy elements (HREY) had the lowest share. Regardless of the lithological type of the analyzed rock, with increasing distance from the intrusion, the percentage of MREY and HREY elements increases at the expense of the light elements LREY. All analyzed distribution patterns of the REYs are characterized by the occurrence of anomalies, which often show a significant correlation with the distance of sampling points from the basaltoid intrusion. The specific distribution of REYs in the vicinity of the intrusion of igneous rocks is an indication of the impact of hydrothermal solutions associated with the presence of basaltoides on the rocks closest to them located at a temperature of over 200°C.

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Autorzy i Afiliacje

Zdzisław Adamczyk
Joanna Komorek
Jacek Nowak
Małgorzata Lewandowska

Abstrakt

The structural pattern developed within metre to microscopic scale thrust and strike-slip fault zones exposed in the Palaeogene flysch rocks of the Fore-Dukla Thrust Sheet in the south-eastern part of the Silesian Nappe, Outer Carpathians, Poland, reveals evidence for upper crustal deformation and fluid flow. Syntectonic dawsonite [NaAlCO3(OH)2] indicates the following series of deformational events within the fault zones: i) detachment and buckle folding resulting from movement along thrust faults; ii) faulting as a compensation of the shortening, resulting in the fault propagation folding, breakthrough thrust faulting and imbrications; and iii) strike-slip faulting. The microstructural pattern coupled with the growth of a related sequence of carbonate minerals within the fault zones, followed by present-day dawsonite precipitation and tufa formation, indicate a continuing influence of fluids within the Silesian Nappe up to and including modern time. Structural observations at metre to microscopic scales coupled with EDS mapping of rocks indicate that dawsonite is a unique tool for the reconstruction of subsequent deformation in the Fore-Dukla Thrust Sheet.

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Autorzy i Afiliacje

Barbara Rybak-Ostrowska
Arkadiusz Gąsiński
Grzegorz Kaproń

Abstrakt

The Rzeszów thrust-top basin was formed on the active Skole thrust sheet of the Outer Carpathian fold-andthrust belt and filled with Miocene syntectonic sediments. New seismic 3D, well and field data were used to define the relationship between sedimentation and tectonic activity and to establish the synkinematic context of the Rzeszów basin-fill architecture. The basin evolution was controlled by the activity of the Carpathian frontal thrust and hinterland thrusts developed in the forelimbs of folds in the Skole thrust sheet, bounding the basin from the north and south, respectively. The activity of the frontal thrust resulted in hinterland-directed depocentre migration and tilting of the syntectonic stratigraphic sequence. Balanced cross-sections have indicated that during the last compressive stage of deformation, the syntectonic deposits filling the basin were shortened by c. 5%, which resulted in the formation of folds and contractional faults. The architecture of the syntectonic deposits and the development of contractional structures reflect the activity of thrusts bounding the basin during compressive deformation of the Carpathian orogenic belt.

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Autorzy i Afiliacje

Joanna Uroda

Abstrakt

The chevkinite group of minerals are REE,Ti-silicates increasingly recognized as widespread accessory phases in a wide range of igneous and metamorphic parageneses. Members of the group are here recorded from five localities in Poland: a two-pyroxene andesite from the Kłodzko-Złoty Stok intrusion, a trachyandesite intrusion north of the Pieniny Mountains, a rapakivi-type granite from the Krasnopol intrusion, an anorthosite from the Suwałki Anorthosite Massif, and nepheline syenite from the Ełk syenite massif. Specific members found are chevkinite-(Ce), perrierite-(Ce) and, potentially, the Al-dominant analogue of perrierite-(Ce). The case is made that chevkinite-group minerals will, through systematic investigation, be found in a wide range of Polish igneous and metamorphic rocks.

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Autorzy i Afiliacje

Krzysztof Nejbert
Bogusław Bagiński
Jakub Kotowski
Petras Jokubauskas
Edyta Jurewicz
Ray Macdonald

Abstrakt

Most of the Frasnian regional stages of the Ukhta region, South Timan, Russia, are composed of basinal deposits, however, the hassi and jamieae zones of the Standard Conodont Zonation cannot be easily recognised in this region. A revision of the previously elaborated succession of the Timan-Pechora associations revealed that the correlation problems are connected with the taxonomic interpretation of the zonal species Palmatolepis hassi and Palmatolepis jamieae. Analysis of the conodont collection of Professor W. Ziegler from the Rhenish Slate Mountains, Germany, especially from the interval encompassing the Lower hassi to Upper rhenana zones, has provided evidence of the lack of validity of the jamieae Zone as a separate stratigraphic unit. This statement is based on the composition of the jamieae and Lower rhenana conodont associations and the absence of P. jamieae near the lower boundary of the zone in the stratotype and other sections of the Rhenish Slate Mountains, becoming more common upsection. The correlation between the Timan-Pechora conodont associations III–XI, the Standard Conodont Zonation (Ziegler and Sandberg 1990) and the Frasnian Zonation (Klapper 1989; Klapper and Kirchgasser 2016) is suggested herein. The Domanikian Regional Stage corresponds to the punctata–Late hassi zones of the Standard Conodont Zonation and to Frasnian Zones 5–10. The boundaries of Frasnian Zones 8–9 need to be further specified in South Timan. The correlation between the Standard Conodont Zonation and the Frasnian Zonation of Klapper is elaborated.

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Autorzy i Afiliacje

Nonna S. Ovnatanova
Lyudmila I. Kononova

Abstrakt

Three trackways attributable to the ichnospecies Bifurculapes laqueatus Hitchcock, 1858 found in Lower Jurassic rocks of the Newark Supergroup in northeastern North America are preserved in association with current lineations. Each trackway takes turns so that parts of the trackway parallel the current lineations. This parallelism is interpreted as evidence that the trackmakers were entrained in flowing water and had to change course due to the current. If this interpretation is correct, then morphological differences between B. laqueatus and terrestrial insect trackways could be explained by the trackmaker moving subaqueously. Further, B. laqueatus would constitute only the second insect trackway from this region to be recognized as being made subaqueously. From an ecological standpoint, the aquatic insects that made B. laqueatus were probably near the base of the local food chain, the apex predators of which were piscivorous theropod dinosaurs.

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Autorzy i Afiliacje

Patrick R. Getty

Abstrakt

Cephalopod specimens assigned to the Argonautidae (Obinautilus pulchra Kobayashi, 1954 and an unknown taxon) from two localities of the Mishan Formation in Gohreh and Khorgu sections, Bandar Abbas, southern Iran, are reported for the first time from the Persian Gulf area. The co-existing foraminifera confirm the middle Miocene age of the strata. Based on micropalaeontological data, the previous Oligocene age of Obinautilus pulchra is extended to the middle Miocene. The palaeobiogeographic distribution of the reported Argonautidae shows that the presence of these faunas is limited to the West Pacific, Indo-Pacific and the East Pacific. The present-day distribution of the Argonautidae is similar to the ancient one and seems to be inherited from their ancestors.

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Autorzy i Afiliacje

Hossein Gholamalian
Mohammad-Javad Hassani
Fatemeh Hosseinipour

Redakcja

Editor-in-Chief
Ireneusz Walaszczyk, Faculty of Geology, University of Warsaw, Poland

Editorial Advisory Board Andrzej Radwański, University of Warsaw, Poland Zdzisław Bełka, Adam Mickiewicz University Poland Max Laurence Coleman, The University of Reading, U.K. Jerzy Fedorowski, Adam Mickiewicz University Poland Ryszard Gradziński, Polish Academy of Sciences, Poland Peter J. Harries, University of South Florida, USA John W.M. Jagt, Natuurhistorisch Museum Maastricht, The Netherlands William James Kennedy, Oxford Natural History Museum, U.K. Jan Kutek, University of Warsaw, Poland Anatoly MikhailovicNikishin, Moscow State Univesity, Russia Nestor Oszczypko, Jagiellonian University, Poland Michał Szulczewski, University of Warsaw, Poland Karl-Armin Tröger, Technische Universiät, Freiberg, Germany Sue Turner, Queensland Musem, Australia Alfred Uchman, Jagiellonian University, Poland Jerzy Znosko, Stage Geological Survey, Poland Andrzej Żelaźniewicz, Polish Academy of Sciences, Poland

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