Andrzej Ślączka

Geodynamic evolution and palaeogeography of the Polish Carpathians and adjacent areas during Neo-Cimmerian and preceding events (latest Triassic-earliest cretaceous)

Abstract The aim of this paper is to place the geodynamic and palaeogeographical evolution and position of the major crustal elements of the Polish Carpathians within a global framework. Neo-Cimmerian movements and their synsedimentary consequences are the main objects of our elaboration in relation to sedimentary record. Five time-interval maps are presented, which depict the plate-tectonic configuration, palaeogeography and lithofacies for the circum-Carpathian region and adjacent areas from the Late Triassic through to the Early Cretaceous. Almost simultaneous tectonic events proceeding within different types of Carpathian sedimentary basins (Pieniny Klippen Belt and Outer Carpathian Silesian Basins) indicate the very important role of the Neo-Cimmerian movements (mainly of the Osterwald Phase) in the geodynamic history of the northernmost margin of the Tethyan Ocean. The global plate reorganization is related to this Tethyan Neo-Cimmerian tectonic activity.

Olistostromes of the Pieniny Klippen Belt, Northern Carpathians

The olistostromes form two belts within the Pieniny Klippen Belt (PKB) in the Northern Carpathians. They mark an early stage of the development of the accretionary prism. The first belt was formed during Late Cretaceous time as a result of subduction of the southern part of the Alpine Tethys. The fore-arc basin originated along this subduction zone, with synorogenic flysch deposits. Huge olistoliths deposited within the Cretaceous–Palaeogene flysch of the Zlatne Basin, presently located in the vicinity of the Haligovce village (eastern Slovakia), provide a good example of the fore-arc olistostrome setting. The second belt is related to the movement of the accretionary prism, which overrode the Czorsztyn Ridge during Late Cretaceous–Paleocene time. The destruction of this ridge led to the formation of submarine slumps and olistoliths along the southern margin of the Magura Basin. The Upper Cretaceous – Paleocene flysch sequences of the Magura Basin constitute the matrix of olistostromes. The large Homole block in the Jaworki village represents the best example of the Magura Basin olistolith. Numerous examples of olistoliths were documented in western Slovakia, Poland, eastern Slovakia and Ukraine. The olistostromes formed within the Zlatne and Magura basins orginated during the tectonic process, forming the olistostrome belts along the strike of the PKB structure.

Occurrence of Upper Jurassic–Lower Cretaceous black organic-rich pelitic sediments as targets for unconventional hydrocarbon exploration in the Outer Carpathians and adjacent part of the Alps

Our work on the dark pelitic sediments of the Polish Carpathians and eastern Alps shows that these Jurassic through Lower Cretaceous sediments owe their organic content to a combination of global processes, such as climatic changes and changes to the carbonate compensation depth (CCD), and local controls, such as basin morphology, input of terrestrial organic material, and local volcanic activity. These sediments developed in basins both floored by oceanic crust as well as within the continental crust (North European platform). Our data show that these anoxic or poorly oxygenated deposits (average total organic carbon [TOC] value is around 2.5 wt. %) were laid down in the individual basins at different times, from the Late Jurassic to the Barremian and almost continuously up to the early Cenomanian, a period of 30 to 50 m.y., and their thickness reached hundreds of meters. This long time span made it impossible to distinguish precisely the known Aptian and Albian oceanic anoxic events (OAE). Our data show that sedimentation of dark organic-rich deposits was not only controlled by global events such as climatic and CCD changes, but also by local ones as a result of differences in their basin morphology and development, input of land-plant detritus, and local volcanic activity. As an example of the anoxic succession, a detailed description of the black sediments of the proto-Silesian basin is presented. Some of these anoxic shales were buried to a depth of a few thousand meters during the folding and overthrusting movements. We propose that these shales could represent a unique shale-oil and shale-gas resource in an intensely structured basin.

Soft-sediment deformation structures in seismically affected deep-sea Miocene turbidites (Cilento Basin, southern Italy)

Abstract Soft-sediment deformation structures (SSDS) are widespread in the upper part of the S. Mauro Formation (Cilento Group, Middle-Late Miocene). The succession is represented mainly by thick and very thick, massive, coarse-grained sandstones, deposited by rapid sedimentation of high-density turbidity currents. The most common SSDS are short pillars, dishes, sedimentary sills and convolutions. They occur mostly in the upper parts of sandstone beds. Vertical tubes of 4-5 cm in diameter and up to 50 cm long constitute the most striking structures. They begin in the middle part of sandstone beds, which are basically massive or contain faint dish structures. These tubes can bifurcate upwards and/ or pass into bedding-parallel veins or dikes. The vertical tubes sometimes form sand volcanoes on the then sedimentary surface. The SSDS are interpreted as the result of earthquake-triggered liquefaction and/or fluidisation of the turbidites that were affected by the seismic shocks. This implies that the deformed layers should be considered as seismites.

The clasts of Cretaceous marls in the conglomerates of the Konradsheim Formation (Pöchlau quarry, Gresten Klippen Zone, Austria)

The clasts of Cretaceous marls in the conglomerates of the Konradsheim Formation (Pöchlau quarry, Gresten Klippen Zone, Austria) Investigations were carried out on foraminiferids and radiolaria from redeposited clasts within the conglomerates of the Konradsheim Formation (Gresten Klippen Zone) in the area of the Pöchlau hill, east of Maria Neustift. These shales and marls are of Middle to Late Jurassic and Early Cretaceous age. In the latter clasts, foraminiferal assemblages with Tritaxia ex gr. gaultina as well as radiolaria species Angulobracchia portmanni Baumgartner, Dictyomitra communis (Squinabol), Hiscocapsa asseni (Tan), Pseudodictyomitra lodogaensis Pessagno, Pseudoeucyrtis hanni (Tan), Rhopalosyringium fossile (Squinabol) were found. In one block from the uppermost part of the sequence there is an assemblage with Caudammina (H) gigantea, Rotalipora appenninica and Globotruncana bulloides. However, the brecciated character of this block and occurrence near a fault suggest that it was probably wedged into the conglomerates of the Konradsheim Formation during tectonic movements. In pelitic siliceous limestones below the Konradsheim Limestone radiolarian assemblages of Middle Callovian to Early Tithonian age were found. They enable correlation with the Scheibbsbach Formation. In a marly sequence, above the conglomeratic limestone, the foraminiferal assemblages contain taxa from mid-Cretaceous up to Paleocene. The present biostratigraphic investigation confirmed the previous stratigraphic assignments and imply clearly that the sedimentation of deposits similar to the Konradsheim Formation also occurred at the end of the Early Cretaceous and deposition of conglomeratic limestones within the Gresten Klippen Zone, and especially within the Konradsheim Formation, was repeated several times during the Late Jurassic and Early Cretaceous.

The Upper Cretaceous Ostravice Sandstone in the Polish sector of the Silesian Nappe, Outer Western Carpathians

Abstract The Ostravice Sandstone Member was identified and described as a lithostratigraphic unit in the Polish part of the Outer Carpathians. This division occurs in the lowermost part of the Godula Formation, is underlain by variegated deposits of the Mazák Formation or directly by the Barnasiówka and Lhoty formations, and overlain by the Czernichów Member of the Godula Formation. Domination by thick- and very thick-bedded sandstones, conglomeratic sandstones and conglomerates rich in calcareous clasts, mostly of the Štramberk-type limestones, is typical for the Ostravice Sandstone Member. These deposits are widespread between the Moravskoslezské Beskydy Mountains in the Czech Republic and the Ciężkowice Foothills in Poland. The documentation of the Ostravice Sandstone Member occurrence as well as the petrological, sedimentological features, and inventory of the carbonate clasts are presented here.

Discussion of ‘Olistostromes of the Pieniny Klippen Belt, Northern Carpathians’

J. Golonka, M. Krobicki, A. Waśkowska, M. Cieszkowski & A. Ślączka reply: We welcome the comments by our Slovakian colleagues and their critique of our results, particularly as we have discussed and published papers together several times about our ideas, sometimes, more or less, disputable (Aubrecht et al. 2003, 2006; Krobicki et al. 2003; Krobicki, Aubrecht & Golonka, 2003; Golonka et al. 2006; Pienkowski et al. 2008). We are pleased to see such warm reaction to our work/paper, which is focused on one of the rudimentary questions in the Pieniny Klippen Belt (PKB) area. How many/what kind of olistoliths/olistostromes occur within the inner structure of the PKB, and when and why did they originate mostly during the Palaeogene part of the Mesozoic–Cenozoic history of this region? We expected this discussion earlier. The content of our paper was presented at the 6 th Meeting of the Central European Tectonic Studies Group (CETeG) in Upohlav, Pieniny Klippen Belt, Slovakia (Cieszkowski et al. 2008), and later, at the XIX Congress of the Carpathian–Balkan Geological Association in Thessaloniki, Greece (Cieszkowski et al. 2010; Golonka et al. 2010). Some ideas were also briefly mentioned in the paper by Cieszkowski et al. (2009) in a journal issue edited by D. Plasienka. We assume that the comments are based on recent investigation, because the authors list the grants received to conduct the research. Therefore, the submitted comments sometimes present a point of view different from that published previously by some of the authors of the comments (RA, JM) (see Aubrecht et al. 2003; Krobicki, Aubrecht & Golonka, 2003; Wierzbowski et al. 2006; Pienkowski et al. 2008). The statement, ‘Certainly there are many still unresolved problems in the geology of the PKB, and it ought to be said that the co-authors of this discussion also do not fully agree with all interpretations formulated and illustrated by the first author’ perhaps explains this controversy. Of course, we agree that ‘there are many still unresolved problems in the geology of the PKB’. We also agree with the statement ‘olistostromes and olistoliths are quite frequent, but not omnipresent’. We depicted the distribution of the olistoliths and their relationship to the non-olistolith tectonic units of the PKB in Golonka et al. (2015, figs 3, 8).