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Geological setting and Ediacaran–Palaeozoic evolution of the western slope of the East European Craton and adjacent regions

Poprawa Paweł

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 4

347--380

EN

A set of geological maps and geological cross-sections was prepared to document the geological setting of sedimentary basins developed on the western slope of the EEC and adjacent areas to the west. On the basis of these data and literature on the subject, the evolution of the sedimentary basins in the study area was reviewed, with special emphasis on the Ediacaran–Lower Palaeozoic basin. The basin originated during late Ediacaran rifting, related to the latest stages of breakup of the Precambrian super-continent Rodinia/Pannotia, associated with large-scale igneous activity. The rifting ultimately led to the formation of the Tornquist Ocean and subsequently, during the latest Ediacaran to Middle Ordovician, the SW margin of the newly formed Baltica became a passive continental margin. The upper Cambrian depocentre in the Biłgoraj-Narol Zone and the Łysogóry Block tentatively is interpreted as a small, narrow foredeep, related to the docking of the Małopolska Block to the western margin of Baltica. From the Late Ordovician through the Silurian, a gradual change to a collisional tectonic setting is observed across the entire SW margin of Baltica, as well as in the zones adjacent to it from the west, which together became the site of development of the extensive Caledonian foredeep basin, related to the convergence and collision of Avalonia and Baltica. The oblique character of the collision resulted in a prominent diachronism in the development of the foredeep basin. This refers to the initiation of basin subsidence, the starved basin phase, the main phase of rapid subsidence and supply of detritus from the west, and the termination of basin development. The Early Mississippian (Bretonian) phase of uplift and erosion and, to a lesser degree, also the Late Pennsylvanian one significantly affected the structure of the western EEC. During the Mississippian, extensive magmatic activity took place at the SW margin of East European Craton, in the region referred to here as the Baltic-Lublin Igneous Province.

2

Ewolucja rowu tektonicznego Nasielsk–Dębe w kredzie

Leszczyński K.

Biuletyn Państwowego Instytutu Geologicznego

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2017

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nr 470

49--62

PL

Badania nad kredową ewolucją rowu tektonicznego Nasielsk–Dębe oparto na danych z otworów wiertniczych Dębe 1, 2, 5, 6, i 7 oraz Nasielsk 1 i 2. W analizie profili otworów wiertniczych wykorzystano tylko krzywe pomiarów geofizycznych oraz materiały archiwalne (opisy rdzeni wiertniczych) i publikowane, ponieważ nie zachowały się rdzenie z tych otworów. Na podstawie analizy miąższościowej zaprezentowano etapy rozwoju rowu w kredzie i skorelowano je z cyklami depozycyjnymi. Zaobserwowano większe różnice miąższości poszczególnych pięter i ogniw po obu stronach północno-wschodniego uskoku rowu, co świadczy o jego większej aktywności w stosunku do południowo-zachodniego uskoku, zasadniczo w ciągu całej kredy. Stwierdzono istnienie przynajmniej dwóch powierzchni nieciągłości (reprezentowanych być może przez powierzchnie twardych den): na granicy kampan/mastrycht i na granicy dolny/górny mastrycht. W obrębie cyklu niższego rzędu K4-IV zaproponowano wyodrębnienie dwóch osobnych cykli najniższego rzędu: K4-IVa korelowanego w przybliżeniu z późnym wczesnym mastrychtem i K4-IVb odpowiadającego przypuszczalnie wczesnemu późnemu mastrychtowi.

EN

The paper portrays the geological evolution of the Nasielsk–Dębe tectonic graben during Cretaceous times. The analysis is based on data from the Dębe 1, 2, 5, 6, and 7 and Nasielsk 1 and 2 boreholes. Only well logs, archived borehole materials (drill core description) and published data have been used because the drill cores are no longer available. The graben’s Cretaceous evolutionary stages have been identified based on thickness analysis, and correlated to depositional cycles. The analysis shows that greater thickness gradients are observed at the north-eastern graben-bounding fault, which indicates its higher activity compared to the south-western fault throughout nearly the entire Cretaceous. The upper part of the Cretaceous succession reveals the presence of at least two discontinuity surfaces (possibly even hardgrounds): approximately at the Campanian/Maastrichtian boundary, and near the lower Mastrichtian/upper Maastrichtian boundary. It is suggested to distinguish two separate lowest-order cycles within the lower-order cycle K4-IV: cycle K4-IVa correlated approximately with the late early Maastrichtian, and cycle K4-IVb corresponding roughly to the early late Maastrichtian.

3

Jeszcze raz o terranach w Polsce i ich wędrówce

Nawrocki J.

Przegląd Geologiczny

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2015

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Vol. 63, nr 11

1272--1283

EN

Results of interdisciplinary studies conducted until now lead to a univocal conclusion that Poland should be regarded as a collage of terranes of different ages and provenances of the basement, and different amalgamation and accretion scenarios. Geophysical and tectonic-structural investigations have allowed defining, with different accuracies, the boundaries between particular terranes. Terranes located in the area of Paleozoic platform were subjected to two or three phases of mobility. The first phase of transcontinental scale was manifested by large-scale tectonic transport during rebuilding of global paleogeography. The second mobility phase of regional scaleaffected the Teisseyre-Tornquist terrane assemblage and was linked with the Laurentia and Avalonia collision. This process put in motion the escape tectonics in the earliest Devonian. As its result, some of terranes were reshuffled during their tectonic transportation in the SE direction. The third, Carboniferous phase of mobility of only local scale was related mainly to the dextral strike-slip tectonic activity. Unfortunately, in the case of several tectonostratigraphic units, an answer to the questions concerning their initial location and way of migration is still impossible. It is valid also in the case of the Teisseyre-Tornquist terrane assemblage, now located to the SE of the Moravia and Grójec fault zones. This reticence in geological diagnosis occurs in spite of generally good access to the rocks of the Brunovistulia and Małopolska terranes that could contain substantial information about the earliest stages of evolution of these units. In order to eliminate numerous gaps in our knowledge about the Polish terranes a new interdisciplinary scientific program should be developed.

4

Results of shallow scientific drillings in the Upper Nysa Kłodzka Graben and the Zieleniec area, Sudetes

Kozdrój W.

Geologia Sudetica

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2014

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Vol. 42

149--159

EN

A set of four new research boreholes, up to 200 m deep, were accomplished in the Nysa Kłodzka Graben and adjacent area, namely: Gniewoszów PIG-1, Międzygórze PIG-1, Krosnowice PIG-1 (plus Krosnowice PIG-1bis) and Zieleniec PIG-1. All boreholes were localized close to the important “frame dislocations” which determine the border between the graben filled with Upper Cretaceous sedimentary rocks and crystalline basement building the Orlica–Śnieżnik Dome. A purpose of the drillings was to confirm the presence of supposed thrusts or reverse faults, which was postulated for some of these dislocations in the past. Out of four boreholes, Upper Cretaceous rocks were encountered below metamorphic rocks only at one, Zieleniec PIG-1, in the strongly deformed footwall of the Zieleniec thrust. The deformed footwall and lack of fault-related folds in the region cast doubts on the thrust interpretation. In four other boreholes that drilled the footwalls of other supposedly reverse faults, Upper Cretaceous rocks invariably show signs of multiple tectonic deformation, which confirms multi-stage evolution of the Nysa Kłodzka Graben, first under extensional and then under compressional regime with duly changing kinematics.

5

The tectonic evolution of Lake Eğirdir, West Turkey

Karaman M. Erkan

Geologos

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2010

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Vol. 16, No. 4

223--234

EN

Lake Eğirdir is one of the most important fresh-water lakes of Turkey. It has a tectonics-related origin. The area formed under a roughly N-S compressional tectonic regime during the Middle Miocene. The stresses caused slip faults west and east of Isparta Angle, and the lake formed at the junction of these faults. The area subsided between normal faults, thus creating the topographic condition required for a lake. The lacustrine sediments have fundamentally different lithologies. After the Late Miocene, central Anatolia started to move westwards, but western Anatolia moved in a SW direction along the South-western Anatolian Fault , which we suggest to have a left lateral slip, which caused that the Hoyran Basin moved t7 km towards the SW and rotated 40º counterclockwise relative to Lake Eğirdir.

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Jurassic - Early Cretaceous development of the peri-Carpathian (SE) segment of the Mid-Polish Trough in the light of results of analogue models

Gutowski J., Koyi H.

Volumina Jurassica

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2006

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Vol. 4, no. 1

45-46

EN

A series of analogue models are used to demonstrate how multistage development of the Mid Polish Trough (MPT) can be influenced by oblique basement strike-slip faults (Gutowski & Koyi 2006). In the light of the results, Jurassic - Early Cretaceous tectonic evolution of the SE Mid-Polish Trough can be interpreted in terms of relative movement of basement blocks bounded by strike-slip faults which segmented the basin. Based on interpretation of geophysical, well and outcrop data, the following successive stages in the basin history are simulated in the models: 1. Oblique extension of the NW segment of the MPT accompanied by sinistral movement along the Holy Cross Fault Zone (HCF, Early Triassic - latest Early Jurassic). 2. Oblique extension of both the NW and SE segment of the MPT, parallel to the HCF (latest Early and Middle Jurassic). 3. Oblique extension of the SE segment of the MPT and much lesser extension of its NW segment connected with dextral movement along the HCF (Early Oxfordian - latest Early Kimmeridgian) (Fig. 1A). 4. Oblique extension of the SE segment of the MPT and much lesser extension of its NW segment connected with dextral movement along the Zawiercie Fault (ZF, latest Early Kimmeridgian - Valanginian) (Fig. 1B). The different sense of movement of the HCF and ZF resulted in successive extensional en echelon fault systems, which widely penetrated the south-western margin of the MPT (Fig. 1). The en echelon fault systems interfered with the SW bounding fault system of the MPT. The NE margin of the SE segment of the MPT is a typical, steep and distinctly marked graben margin fault zone, dominated by normal and dip-slip/strike slip faults parallel to its axis. A specific pull apart basin developed in the zone between the HCF and SW border fault of the SE segment of the MPT during Oxfordian and Early Kimmeridgian times (Fig. 1A). It resulted from interaction between the en echelon fault system and dip slip fault system bounding the MPT. Extensive south-westward progradation of the shallow water carbonate and continental clastic depositional systems of the Late Oxfordian - Early Kimmeridgian onto the central part of the basin located above the HCF was controlled by development and propagation of en echelon relay ramps along the NE wedge of the MPT (Fig. 1A''). These ramps were faulted during the Late Kimmeridgian-Tithonian - earliest Berriasian due to reorientation of the extension direction from WNW-ESE to W-E (Fig. 1B'-B''). Dextral strike-slip movement of the HCF was replaced by dextral strike slip movement along the ZF. The same mechanism controlled also propagation of the depocenter from the western to the eastern margin of the basin.