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Content available Katalog basenów sedymentacyjnych Polski
PL
Na obszarze Polski wyróżniono 48 basenów sedymentacyjnych obejmujących utwory od ediakaru po pliocen. Opierając się głównie na dostępnych opracowaniach publikowanych, w tym kartograficznych, określono granice basenów, stosując oprogramowanie ArcGIS, a także zestawiono krótkie opisy poszczególnych jednostek. W opisach zarysowano ich zasadnicze cechy: plan strukturalny, wiek wypełnienia osadowego i jego charakterystykę, powierzchnię wychodni, zasięg regionalny na tle elementów tektoniki i paleogeografii oraz genezę. Baseny zaliczono do czterech ogólnych kategorii regionalnych: epikontynentalne (24), włączone w górotwór (14), śródgórskie (4) i związane z terranami (6). Większość opisanych jednostek (32) należy do basenów wychodzących poza granice Polski. Powierzchnia wychodni basenów (w granicach kraju) mieści się w szerokim zakresie: od 11 km2 (basen zgorzelecki) do 284 761 km2 (mezozoiczny basen Niżu Polskiego), przy średnim obszarze 27 290 km2. Nieliczne baseny (w zależności od interpretacji podłoża: 9–15) są rozwinięte bezpośrednio na fundamencie krystalicznym, znaczna większość została nałożona na jednostki powstałe wcześniej, nierzadko w wyniku reaktywacji dawniejszych ram tektonicznych. Głównie na podstawie prac publikowanych przedstawiono zarys genezy poszczególnych basenów, a także wstępnie zaliczono je do ośmiu kategorii genetycznych: obrzeże pasywne, pasmo fałdowo-nasuwcze, basen: przedgórski, przedłukowy, pull-apart, śródkratoniczny, ryftowy i załukowy. Baseny poligenetyczne, o wieloetapowej historii rozwoju, zaliczono do kategorii odnoszącej się do etapu inicjacji basenu. Luki w rozpoznaniu niektórych opisanych basenów sprawiają, że w miarę dopływu nowych materiałów badawczych może ulec zmianie ich definicja, ewentualnie nastąpi ich wewnętrzny podział regionalny lub stratygraficzny, czy też połączenie z sąsiednimi jednostkami.
EN
The catalogue provides description of 48 sedimentary basins from the territory of Poland, comprising deposits from Ediacaran to Pliocene. Basin boundaries in the Arc GIS format, as well as short descriptions of particular units, have been based mainly on published data, including cartographic materials. Descriptions include essential characteristics such as: structural plan, age and general features of a sedimentary fill, regional extent against tectonic and paleogeographic boundaries, and brief genetic considerations. The basins were ascribed to four general regional categories: epicontinental (24 units), incorporated in an orogen (14), intramontane (4), and associated with allochthonous terranes (6). The basin area, defined here as the present area of outcrops or subcrops, ranges from 11 km2 (Zgorzelec Basin) to 284,761 km2 (Mesozoic Basin of the Polish Lowlands), with a mean of 27,290 km2. Most of the described units (32) extend beyond the Polish territory into surrounding countries. Some basins (depending on the basement interpretation: 9-15) are developed directly on a crystalline basement. Majority of basins onlap earlier units, commonly due to reactivation of the pre-existing tectonic framework. A brief review of mechanisms that led to basin formation allowed the authors to ascribe the units to eight genetic categories: passive margin, fold-and-thrust belt, foreland, fore-arc, pull-apart, intracratonic, rift, and back-arc basins. In several instances of polygenetic (polyhistory) basins they were included to a category corresponding to the initial stage of basin development. The present study pinpoints some gaps in our knowledge of particular basins. Once filled, they may lead to changes in basin concepts and definitions, and also to their further subdivision or, conversely, unification.
EN
In the Pieniny Klippen Belt (PKB), the Cretaceous and Paleogene conglomerates and cohesive debrites commonly contain pebbles and blocks of the subvolcanic rocks among other, mainly sedimentary rocks (e.g. multicoloured sandstones, oolitic limestones, dark bivalve coquinas, dolostones, etc.). This detritus was interpreted as derived from the Andrusov Ridge located south of the PKB basin (Birkenmajer, 1988). Age of these subvolcanic rocks, regarded to represent subduction-related igneous activity, was previously constrained by K-Ar whole rock dating as c. 140–90 Ma, leading to suggestion that during Late Jurassic to Early Cretaceous PKB basin developed on oceanic lithosphere, subducted during at the end of Early Cretaceous (Birkenmajer, 1988). Within this study, the geochemical composition, the K-Ar whole rock age and the U-Pb zircon ages of the above mentioned subvolcanic rocks were studied. The pebbles are well rounded. They are represented by granitic and subvolcanic andesitic-type rocks (mainly andesite, basaltic andesite, basaltic trachyandesite, trachyandesite and rhyolitic pebbles, and rare dacite, tephrite, trachybasaltic and basaltic pebbles). Domination of andesitic pebbles, bimodal spectrum of volcanic rocks with high content of SiO2 (rhyolites, dacites) and Na2O and K2O within mafic and transitional ones is observed. Their petrographic character and geochemical analysis of concentration of rare elements with MgO > 2% ratio and La/Yb 4–35, Sc/Ni < 1.5, Sr/Y < 20, Ta/Yb > 0.1, Th/Yb > 1 values, indicate magmatic island arc of active continental margin similar to Andean-type subduction regime. The K-Ar whole rock dating was performed for 17 samples. The obtained ages cover mainly the Early Cretaceous time span, with the most data representing the Barremian-Albian, therefore are coherent with Birkenmajer (1988) results. However, the U-Pb SHRIMP zircon dating reveled different results. Most of the analyzed subvolcanic rock samples (9) give ages in the narrow range of c. 270–266 Ma. The ages are based on concordant data with amount of measured point in a range of 20–30, and are characterized by low error bars, usually lower than ±2 Ma. In addition, one sample of subvolcanic rock gave lower quality results, with a few youngest, partly concordant, zircons grains giving the age of 251.0 Ma ±8.5 Ma. Moreover, one sample of orthogenesis was analyzed, which is regarded to represent crust on which the volcanic arc developed. In this case the U-Pb SHRIMP zircon dating result is 493.9 Ma ±4.1 Ma. We regard these pebbles/blocks to be derived from the Inner Carpathians, assuming therefore lack of the Andrusov Ridge located south of the PKB basin (comp. Plašienka, 2018). The results of K-Ar whole rock dating is representative for intensive diagenetic overprint, rather than age of the rock. The U-Pb data clearly indicate, that subduction-related magmatic arc developed during the middle Permian (Guadalupian). This follows, that the oceanic crust was of the middle Permian or older age, and thus cannot be related to the Jurassic-Early Cretaceous development of the PKB basin. The magmatic arc was presumably connected with southern margin of Laurusia and subduction of oceanic crust of the Paleotethys (proto-Vardar Ocean?).
EN
Avalonia was an archipelago of microcontinents divided into West and East Avalonia. West Avalonia included south-eastern parts of Nova Scotia, eastern Newfoundland, New Brunswick, Florida(?), and New England, while East Avalonia included southern Ireland, southern Scotland, England, northern France, the Brabant Massif, Lusatia, northern Germany, and north-western Poland. Several crustal fragments such as the Bruno–Silesia terrane, Moesian terranes, Istanbul/Zonguldak terrane constituted an extension of East Avalonia (Golonka et al., 2023). These microcontinents detached from Gondwana during the Early Paleozoic times. Golonka et al. (2023) also portrayed a chain of microcontinents moving away from Gondwana across the Palaeoasian (Protothetys) Ocean. These chain included Scythian, Turan, South Kazakhstan, Junggar, Tarim and Indochina. The Rheic-Palaeotethys Ocean opened behind these microcontinents. Collision occurred between Avalonia, Laurentia and Baltica during Caledonian Orogeny. This collision also included Bruno–Silesia, Moesia terranes, Istanbul/Zonguldak, Scythian and Turan terranes (Golonka & Gawęda, 2012). The events involving Junggar, South Kazakhstan and Tarim are more speculative. Indochina collided with South China along Song Ma– Truong Song–Ailaoshan suture during latest Silurian–earliest Devonian times. In northwestern Vietnam, the Late Silurian Song Chay complex granitoid is connected to this event. Moreover, the deep-water deposits such as Pa Ham formation were later replaced by shallow-water sedimentary formations, including the continental Lower Devonian red beds and Lower Devonian Nam Pia Formation composed mainly of terrigenous sediments and marl, medium-bedded to massive fine-grained limestone, representing shallow water sediments. The Lower Paleozoic greenschists of deepsea origin were unconformably covered in many localities by Devonian redbeds (Son et al., 1978; Hung, 2010; Hung et al., 2023).
EN
There is a unique tectonostratigraphic unit called Kaminnyi Potik occur in the Ukrainian-Romanian Carpathian transborder zone. In the Ukrainian part numerous outcrops of this unit can be observed in many streams near Rachiv city, but its most spectacular occurrence is in the Chyvchyn Mountains. The whole complex consists of volcanogenic-sedimentary rocks and is divided into two Berriasian formations: Chyvchyn and Kaminnyi Potik. In the section of the Chyvchyn Formation, at the base, there are pillow lavas (basalts and andesites/trachyandesites) and volcano-sedimentary breccia with clasts of lava, coral limestones and radiolarites (submarine debris flows), and peperites as well. The Kaminnyi Potik Formation is made up of fine-grained hyaloclastic and carbonate debris flows of a flysch character (including organodetrital limestones with fragments of: corals, bryozoans, echinoderms bivalves and foraminifera), which overlying breccias and coral limestones of the Chyvchyn Formation. The profile ends by thin-bedded cherty limestones. The thin sections analysis revealed the following microfacies: oolithic-echinoderm packstone/grainstone; coral lithoclastic quartz packstone/grainstone; oolithic-lithoclastic wackestone/packstone; lithoclastic-echinoderm packestone; lithoclastic packestone; radiolarian echinoderm packestone; radiolarian wackestone; radiolarian-calpionellid wackestone and mudstone. Pyroclastic material is often present in the matrix. The ooids observed in the thin sections and the remains of fauna such as corals, echinoderms and bivalves suggest that the original material came from a carbonate platform that was sheltered by a coral reef. As a result of volcanic eruptions and possibly accompanying earthquakes, the platform has been destroyed and its traces are visible in clasts. Sedimentological character of submarine debris flows, (e.g. fractional graiding, mixture of shallow-water fauna and lithoclasts with deep-marine microfauna (radiolarians and calpionellids) and hyaloclastic material present in the matrix document short-term episodes of a catastrophic nature, leading to the redeposition of shallow-water sediments to the deeper parts of the basin.
EN
The Cimmerian Continent (or Cimmeria, Cimmerian terrane, Cimmerian blocks) was detached from eastern Gondwana in the Late Paleozoic as a sliver/ribbon of continental strip rifting elements. Recently, these elements belong to an almost continuous long belt (ca. 13,800 km) from central Italy trough Greece, Turkey, Iran, Afghanistan, Tibet, SW China, Myanmar, Thailand up to Indonesia (Sumatra). The palaeogeographic position and relationship of some elements during Permian-Mesozoic times is still matter of discussion. The Qiangtang and Lhasa blocks (present-day Tibet) belong to these elements and their location in space and time and their relationship causes a lot of controversies. Their position alongside eastern Gondwana in the mid-Early Permian (ca. 290–285 Ma) are suggested both by palaeomagnetic and facies studies. Palaeomagnetic studies indicated this position one decade ago, which has been confirmed by recent studies. The Cimmerian Continent [Iran (Alborz)-Qiangtang-Baoshan-Tengchong-Sibumasu] was separated from the Gondwanian part of Pangea during mid-Early Permian time by rifting and drifting. Northwards migration of it took place during Permian-Triassic times caused wide opening of the Bangong‐Nujiang Tethyan Ocean and closing of the Paleotethys Ocean but the Lhasa block was still southern margin of the Bangong‐Nujiang Ocean. The Triassic Indosinian Orogeny has been one of the most spectacular geotectonic event reflecting collision of this continent with Indochina block and closure of the Paleotethys Ocean. The separation of the Lhasa block from Gondwana is enigmatic but most probably took place during earliest Jurassic times. This separation was followed by quick shift northward. Intensive sedimentological studies of the Late Triassic (Carnian-Norian) several flysch-type turbidites in the eastern Tethyan Himalaya (e.g. Qulonggongba, Pane Chaung, Langjiexue, Quehala, Duoburi formations/groups) indicate that their provenance was connected with Lhasa block, which has been their source area during early-stage evolution of the Neotethys. The late Early Permian rift-related basaltic magmatism in northern Baoshan (in SW China) and sourrounding regions was connected with first step of separation from Gondwana margin of this block (together with South Qiangtang and Sibumasu blocks and simultaneously with opening of the Bangong‐Nujiang Ocean before the Middle Permian)  – independently of Lhasa block which was separated later, the most probably during Late Triassic or Triassic/Jurassic transition time with very wide space of the Bangong‐Nujiang Tethyan Ocean between Qiangtang and Lhasa blocks (2,600 km ±710 km  – 23.4° ±6.4° during the Middle Jurassic with its maximum width in the Late Triassic). From the palaeobiogeographic point of view, the worldwide distribution of Pliensbachian-Early Toarcian large bivalves of the so-called Lithiotis-facies, dominated by Lithiotis, Cochlearites, Litioperna genera revealed by the authors’ studies, indicates very rapid expansion of such type of bivalves alongside southern margin of Neotethys, and could be good evidence of palaeogeographic position of the Lhasa block in this time. Himalayan and Tibetan (Nyalam area) occurrences of Lithiotis and/or Cochlearites bivalves could help to place the Lhasa block nearby the Gondwana during Early Jurassic times. This palaeobiogeographic research contradict another interpretation based on different fossils (Permian fusulinids and brachiopods) interpreted as subtropical fauna, which could occur in low subtropical latitudes together with other parts of the Cimmerian Continent.
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