THE GRAPTOLITIC FACIES OF THE CARADOCIAN IN THE ŚWIĘTY KRZYŻ MOUNTAINS Least investigated among the deposits of the older Palaeozoic in the Świety Krzyz Mountains is the Ordovician. There exist but few publications on the stratigraphy of these deposits, and they refer only to incomplete profiles of individual stages, beginning with the Tremadoc and ending with the Ashgillian. Our first cognizance of the Upper Ordovician sediments is of recent date owing to investigations carried out in the 1920th and 1930th years by J. Czarnocki (1928b; 1939) and by J. Samsonowicz (1932, 1934); worthy of note are also the conclusions reached, regarding the straigraphy of the Ashgillian by Z. Kielan (1956).
NEW DATA ON STRATIGRAPHY AND TECTOGENESIS OF THE OLDER PALAEOZOIC IN POLAND
Summary
At the boundary of the Middle and Upper Cambrian an orogenesis of one of the late Salair phases took place, locally determined as the Holy Cross phase. It caused an uplifting of the southern area, and a retreating of the Upper Cambrian basin to the Łysogora area. The successive Sandomirian phase, corresponding to the Sardian phase, interrupted, at the boundary of the Upper Cambrian and the Tremadocian or lowermost Tremadocian, the cycle of the Upper Cambrian sedimentation in Łysagora Mts, uplifting this area and simultaneously lowering the southern region, where the transgressive Upper Tremadocian invaded, giving distinct discordances in relation to the Precambrian or Lower or Middle Cambrian. Further phenomena of movements still genetically connected with the Sandomirian phase appeared only at the Upper Lanvirnian time (Didymograptus murchinsoni). These may be referred to the young Sardian movements or to the Vermont phase in Scandinavia. However, the author has distinguished these movements and called them the Łysogora phase. This latter lowered the elevation in Łysogora Mts, where, for the first time the Ordovician of Llandeilo age entered their northern slope and ended the sedimentation of the shallow-neritic Lower Ordovician in the central part (Tab. I), and considerably shallowed the existing depression of Brzeziny.
This conformity of the geological phenomena is the best prove of movements, which has been reported even from the platform area, and the fore-field of the Carpathians, as well.
The distribution of facies of the discussed formations does not prove the regional-structural subdivisions by J. Czarnocki, i. e. the Łysagora-geosynclinal region and the separate Kie1ce-geanticlinal region, all the more the conclusions by J. Znosko, who states that the movements of the Caledonian orogenesis have only been restricted to the Kielce region, and these of the Hercynian orogenesis to the Łysogora region.
SILURIAN STRATIGRAPHY IN NORTHEASTERN POLAND In 1957-1961 the Silurian deposits of the East-European platform area have been encountered in the following bore holes: Łeba 2, Łeba 3, Bytow, Paslek, Bartoszyce, Goldap, Żebrak, Mielinik, Tluszcz, Krzyze and Kaplonosy. The whole of the material obtained from these bore holes is as much as 8000 m of drill core. The fauna prepared of the drill core is very rich and numerous, thus more detailed study moo the carried on in the future. The Silurian basin in Poland extended over a fairly vast area and constituted the eastern branch of the North-European geosyncline. In the southeast, the basin was restricted by the Świety Krzyz anticlinorium, in the northeast by the East-European platform. In general, it represented a continuation of the Ordovician sedimentary cycle. However, as compared with the Ordovician basin, the sedimentary basin of the Silurian in Poland is characteristic of deepening and widening of its extent. The epicontinental character of the sea existing at the Ordovician time considerably changed during the Silurian into a miogeosynclinal one, especially in the central part. As concerns lithological development and zonal distribution of shallower and·deeper neritics, the Silurian of the platform is closely connected with the Russian platform area, particularly with the Silurian of the Baltic countries, and with the Scania area, partly also with the Silurian of Gotland. Moreover, the shallower neritics show great analogies with the Silurian occurring in the Wolynia and Podolia areas. A similarity to the area of the Świety Krzyz Mts. is also distinctly visible, particularly as concerns the Platform Silurian deposits which have been reached within the deeper zones of the so-called marginal synclinorium in such profiles as Lebork, Bytow, Paslek and Żebrak. In these profiles an argillaceous facies with graptolites predominates. Sporadically, there occur also calcareous lenses and concretions which are found in the Bardo and the Prągowiec beds of the Świety Krzyz Mts. The so far applied subdivision of the platform Silurian in Poland shows that almost all the equivalents of the graptolite zones are here richly represented by species of index graptolites (see stratigraphical table) proving an open basin character and a convenient connection with the neighbouring areas. The stratigraphical subdivision of the Silurian is mainly based on the assemblages of graptolites represented here in quantities. For individual complexes or stratigraphical series the author introduced new nomenclature of beds. Hence, the lowermost Paslek beds are an equivalent of both Llandoverian and Wenlockian stages, however, the Mielnik beds comprising also the zone Saetograptus leintwardinensis and the overlying Siedlce beds together with the extension area of the graptolites ex gr. formosus , correspond to the Lludlovian stage. A detailed description of these·beds and a list of faunal assemblages occurring in the area discussed, are given in the Polish text. The upper argillaceous deposits with graptolites appearing above the Siedlce beds probably are not an equivalent of the British Lludlovian stage. Therefore, the so far determined deposits as Podlasie beds are called now by the present author - Podlasie stage. As concerns the platform Silurian in the argillaceous fades with graptolites, this stage should characterize the younger deposits than the equivalents of the British Lludlovian stage, however, with tills reservation that there does not exist a detailed correlation of the top part of the Siedlce·beds o)r of the bottom part of the Podlasie stage with the uppermost Lludlovian (Upper Whitcliffe·beds) of Great Britain. In the bore hole Kock a trylobite Acastella heberti elsana has been found to occur in the argillaceous fades without graptolites. This form is characteristic of the lower part of the Bostow beds in the northern area of the Świety Krzyz Mts. It is also possible that the deposits of Kock, determined as Kock beds, may already represent the equivalents of the lowermost Gedinnian and are younger than those of the Podlasie stage (E. Tomczykowa, 1962).
OLDER PALAEOZOIC IN BORE BOLE WILKOW NORTHERN PART OF THE ŚWIĘTOKRZYSKIE MOUNTAINS Summary Bore hole Wilkow, situated in the Łysogory area (northern part of the Świetokrzyskie Mountains), has pierced the deposits of Older Palaeozoic age. The distribution of these deposits is shown in Fig. 2 and Table 1. The Upper Cambrian, mainly of clay-siltstone character, subordinately arenaceous at the bottom, makes here a complex about 150 m in thickness. Trilobite ascertained here by E. Tomczykowa (1968), i.e. Peltura scarabaeoides westergardi Henningsmoen (at a depth of 857 m) and Parabolina lobata lobata (Brogger) represent the lower Łysogory beds, mainly of the zone 5 c. Any higher beds of Cambrian age have not been found to occur at Wilkow, despite the fact that the following sub-zones have been ascertained (E. Tomczykowa, 1968) in the neighbouring section: 6 a Parabolina latilimbata Tom.,6 b Beltella rotundata Tom., 6 c Parabolina bukowiana Tom., and 6 d Parabolina acanthura (Angelin). A considerable gap exists between the Cambrian and Ordovician, since the Upper Cambrian is unconformably overlain with the Caradocian deposits of the zone Diplograptus multidens. Higher up, the Lower Ashgilian deposits have been found to contain trilobites Tretaspis and Eodindymene. At the contact of the Ordovician with Silurian another stratigraphical gap appears since no zones of the lowermost Llandoverian has been ascertained, as far as the zone Monograptus sedgwicki. Higher up are claystones and graptolite schists of Wenlockian age (the so-called upper Ciekoty schists) and then of Ludlovian age (the so-called Wilkow schists - H. Tomczyk, 1962). The Silurian clay deposits predominate to a depth of 420 m (Fig. 2), and only in the lower part of the zone Saetograptus leintwardinensis, siltstone and then greywacke intercalations appear. The zone S. leintwardinensis is here considerably thick (432 - 273 m). These facts prove the conclusion drawn by H. Tomczyk (1956) that at the close of the Lower Ludlovian (Wilkow schists) the deposits of clay lithofacies disappear, and the graptolite assemblage becomes poorer, a fact characteristic not only of the area of the Świetokrzyskie Mountains. The Upper Ludlovian deposits of the Wydryszow beds reach, in the Łysogory area, up to 2000 m in thickness. In the section at Wilkow, only the lowermost part of these beds has been pierced, from 275 to 6 m (Fig. 2). These area alternating claystones and siltstones, with intercalations of greywackes, revealing features of flysch-like deposits (J. Czarnocki, 1967), characterized by diagonal and convolute laminations, with few graptolites Pristiograptus bohemicus (Barr.). The Wydryszow beds bear a marked lithological and stratigraphical analogy to the Siedlce beds of the platform area. The whole complex of the Older Palaeozoic deposits, encountered in bore hole Wilkow, show an analogous degree of tectonic disturbances, without distinct folding and cleavage. The dips, amounting to 40 - 30°, directed northwards, slightly change in the fault zones (Fig. 2). The faults are responsible here for a tectonic reduction of certain stratigraphical horizons. Particularly interesting are discordances that have taken place at the boundaries Upper Cambrian - Ordovician and Ordovician - Silurian. The great stratigraphical gaps (Table 1), observed to occur in this area, already primarily revealed features of a sedimentary hiatus, connected with the Caledonian epeirogeny. The sedimentary gap that existed before the sedimentation of the Lower Jeleniow beds of Llandeilo age, is connected with the Łysogory phase, whereas the younger one, at the boundary Ordovician - Silurian, is related to the Taconian phase (H. Tomczyk, M. Turnau-Morawska, 1967). Summing up the tectonical problems we should emphasize that the Upper Cambrian and the Ordovician deposits of the Jeleniow and the Wolka beds, as well as the Silurian deposits, the Wydryszow beds inclusive, constitute a uniform structural stage that in the Łysogory area was formed during the Hercynian orogeny and, maybe, began with the Young Caledonian activity at the close of the Ludlovian time.
Ordovician and Silurian in the absement of the Fore-Carpathian Depression
W niniejszej pracy autor przedstawil stratygrafie utworow ordowiku i syluru, stwierdzonych w profilach wiercen na obszarze Przedgorza Karpat (zapadliska przedkarpackiego). Przeprowadzil on korelacje utworow ordowiku i syluru z utworami tego wieku wystepującymi w Gorach Świetokrzyskich i na obszarze platformy wschodnioeuropejskiej. Nastepnie wprowadzil nową nomenklature warstw dla udokumentowanych osadow ordowiku i syluru, podaje ich charakter litofacjalny z wystepującymi tam zespolami fauny, szerzej uzasadnia wydzielone poziomy stratygraficzne oraz regiony paleogeograficzne — lokalne. W podsumowaniu autor wypowiada sie odnośnie do kierunkow migracji planktonu graptolitowego oraz co do procesow orogenicznych, ktorych wiek w podlozu zapadliska przedkarpackiego przypadac moze na pogranicze syluru a dewonu.
The author presents the stratigraphy of the Ordovician and Silurian formations discovered by bore-holes in the basement of the Fore-Carpathian Depression. Correlations with coeval formations present in the Holy Cross Mts and on the East European Platform are presented, and new names introduced for the members of the Ordovician and Silurian in the Fore-Carpathian Depression. Lithofacial development, faunal assemblages, and paleogeographical regions are discussed, as well as directions of migration of the graptolite plancton. The age of orogenic processes which folded the Early Paleozoic rocks in the Fore-Carpathian Depression is referred to the Silurian — Devonian boundary.
PALEOZOIC STRIKE-SLIP MOVEMENTS IN SOUTHERN POLAND
Summary
Basement of the Northern Carpathians and their direct foreland is formed of strata of the Upper Silesian and Malopolska Massifs. The massif s are bounded by deep crustal fracture systems (26,7) and markedly differ in pre-Permian history. Available radiometric (15,39) and geological data show that Cadomian movements affected both massif s and the stage of these movements is common for their history. Effects of subsequent, Early Caledonian movements are confined to the Malopolska Massif s and Cracow-Myszkow zone, and of the Late Caledonian ones - to that zone, being unknown from the Upper Silesian Massifs. The key to explain these and other differences in history of the massifs has to be looked for in tectonic nature of zone of their contact, i.e. the Cracow-Myszkow zone.
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TECTONICS AND PALEOTECTONIC EVOLUTION OF THE PRE-PERMIAN PALEOZOIC BETWEEN KOSZALIN AND TORUŃ (POMERANIA)
Summary
The tectonic structure of pre-Permian Paleozoic in the platform contact zone between Koszalin and Torun was reanalysed mainly on the basis of data from deep drillings and refraction seismics surveys. In this area, Paleozoic complexes occurring in the foreland of the East-European Precambrian Platform differ from those of sedimentary cover of the latter in thickness, facies development, tectonic history as well as style and directions, and appearance of Upper Silurian - Devonian - Carboniferous cover. A special attention should be paid to band-like pattern of blocks, roughly parallel to margin of the East-European Platform. Besides eventual Grampian stage, here may be differentiated two structural stages of pre-Permian Paleozoic. Lower stage is built of strongly deformed Ordovician and Lower Silurian rocks, and the upper - of Upper Silurian, Devonian and Carboniferous ones. The lower stage appears the thickest (5000-6000 m thick) in blocks situated in direct foreland of the East-European Platform and refraction seismics data show (Fig. 2) that it suddenly thins out to about 3000 m or less at a line running about a dozen to 25 km SW of the platform margin. Together with negligible thickness of the Ordovician in marginal part of the East-European Platform (15) this gives the appearance of synsedimentary trough for the zone of increased thickness of the Ordovician and Lower Silurian (17).
The age of disturbances or foldings of rocks belonging to the lower structural stage remains the subject of discussions. However, in the light of the available data it may be stated that the peak of deformations dated at the tum of, the Wenlockian and Ludlovian (2) seems more probable than any phase from the tum of the Silurian and Devonian or early Devonian (5). The Mid-Silurian and not younger age of these disturbances is primarily suggested by the continuity of sedimentation at the tum of the Silurian and Devonian, recorded in the Radom - Lublin sector of the contact zone of the East- European -Precambrian and Mid-European Paleozoic Platforms (12), and cover character of Upper Silurian-Lower Devonian sequences in relation to disturbed Lower Silurian and older ones in the Radom region. Disturbances of the Lower Paleozoic in the foreland of the East-European Platform seem connected with deep crustal fractures of the strike-slip fault type and not the existence of Central-European branch of the Caledonian geosyncline (see also (8)). Such interpretation does not exclude overthrust of these disturbed series on the platform margin. However, such overthrust still remains to be proven.
In the Koszalin - Torun zone, the Upper Silurian - Devonian - Carboniferous cover displays very clearly effects of Variscan block movements. Displacements traceable in basal surface of the Zechstein approach merely 100-200 m whilst those connected with pre-Zechstein block movements may range from about 500 m to some kilometers. Therefore, it should be stated that block movements acting here after the Early Permian did not exort any significant influence on structural -character of pre-Permian Paleozoic.
The biostratigraphic value of graptolites of Polish Silurian is discussed. This group makes possible a detailed zonation of deposits ranging in age from the Llandovery to the Ludlow the teintwardinensls Zone. Younger Silurian deposits of Poland divided into Siedlce and Podlasie Series and subsequently graptolite biozones, represent reference section for Upper Silurian of other regions. Shelly fauna of the Polish Silurian, sometimes accompanied by graptolites, In dicates isolation of shelves of the Gondwanian and Fennosarmatian continents. An attempt is made to reconstruct the history of the Proto-Tethys Ocean separating the continents and its relation to the Proto-Atlantic. Key w 0 r d s: Stratigraphy, paleogeography, graptolites, Silurian, Lower De vonian, Proto-Tethys, Poland.
THE TECTONIC MAP OF POLAND IN THE VARISCAN EPOCH
Summary
The tectonic map of the Caledono-Variscides of Poland was compiled and published in the years 1984 -1992 by a team of geologists of the State Geological Institute and the Polish Oil and Gas Company. The work was initiated by W. Pozaryski who also proposed tectonic interpretation of platform areas of Poland, accepted in this map. For the sake of clarity the information given in the map is limited but attempts were made to give convincing characteristics for each tectonic structure, mainly geostructural character of a given unit, its spatial and time relations to adjacent ones and role in tectonic image of area of the central Europe. A line of Caledonian sinistral shear which formed south-western margin of the East - European Platform is the major tectonic feature of platform areas situated outside the Variscan Deformation Front. The platform margin is usually buried under thick Variscan complex and strata of the Alpine complex. The course of the margin was traced in detail on the basis of refraction seismic data and deep drillings. Refraction horizons, well traceable in sedimentary cover of the East – European Platform, sharply end at the platform margin. The basement of the Paleozoic platform is characterized by highly complex tectonics in area between the above mentioned platform margin and Variscan Deformation Front. It corresponds to Caledonian collage orogen formed of terranes, transported at large distances due to rotation of the Gondwana plate. The terranes were accreted in times of Taconian movements and early phase of the Main Scandic movements. Upper Silurian sediments already display features of molasse of that orogen, East - European Platform. The last phases of Variscan movements resulted in faulting of the foreland in southern Poland, displacements of individual blocks and origin of numerous compressional structures including that of theHoly Cross Mts.
ON HETEROCHRONEITY OF THE TEISSEYRE-TORNQUIST LINE
Summary
There is growing evidence for heterochroneous character of the Teisseyre-Tornquist Line. The section from Koszalin to the Black Sea may be treated as a part of the Caledonian Deformation Front (31-2, 18) and its origin explained as due to sinistral-strike movements. The movements resulted in cutting off a corner of the East-European Platform and its replacement by a part of Early Caledonian fold belt ( 4), developed on Dalslandian-Cadomian basement. This is why this section may be treated as formed of deep crustal fractures marking SW boundary of the East-European Platform.
A right-lateral shearing from the Late Paleozoic (1, 4, 33) resulted in rejuvenation of the Koszalin-Black Sea section as well as origin of its Baltic-Scania extension, thus giving rise to the Teisseyre-Tornquist Line. In the Baltic-Scania section, we are no longer dealing with fractures delineating margin of the East-European Platform but rather those of the intraplatform type. However, the above explanation of the nature of the latter section makes it necessary to assume some deformations of the Caledonian Deformation Front, especially its bending in the Koszalin area, which would precede its formation. This seems to be the case and the deformations may be easily explained by the rotation of Baltica at the turn of the Silurian and Devonian. The right-lateral shearing, following the deformations, could result in some translocation of basement blocks along the whole TTL. Some data (2) suggest dextral translocation of basement blocks along the Romelese horst at about 30 km distance but it remains an open question whether this is due to Variscan movements, Alpine ones or net result of the former and Alpine rejuvenation. A rejuvenation of TTL in the future appears fairly probable.
