Journal of Maps ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/tjom20 Geology of the Magura Nappe, south-western Gorce Mountains (Outer Carpathians, Poland) Mateusz Szczęch & Marek Cieszkowski To cite this article: Mateusz Szczęch & Marek Cieszkowski (2021) Geology of the Magura Nappe, south-western Gorce Mountains (Outer Carpathians, Poland), Journal of Maps, 17:2, 453-464, DOI: 10.1080/17445647.2021.1950579 To link to this article: https://doi.org/10.1080/17445647.2021.1950579 © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group View supplementary material Published online: 12 Jul 2021. Submit your article to this journal Article views: 781 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tjom20 JOURNAL OF MAPS 2021, VOL. 17, NO. 2, 453–464 https://doi.org/10.1080/17445647.2021.1950579 SCIENCE Geology of the Magura Nappe, south-western Gorce Mountains (Outer Carpathians, Poland) Mateusz Szczęcha and Marek Cieszkowskib aFaculty of Geography and Geology, Jagiellonian UniversityInstitute of Geography and Spatial ManagementEO-CHANGE Lab., Krak, Poland; bFaculty of Geography and Geology, Jagiellonian UniversityInstitute of Geological Sciences, Krak, Poland ABSTRACT The studied area, located in the south-western part of the Gorce Mountains, is built of .ysch deposits representing the Krynica and Bystrica Subunits of the Magura Nappe. Here, in the Late Cretaceous–Early Miocene part of the lithostratigraphic succession of the Krynica Subunit, four formations containing several members were distinguished, whereas in the Bystrica Subunit, only one Middle Eocene–Oligocene formation was identi.ed. The Turbacz and Kudłoń Thrust Sheets in the tectonic structure of the Krynica Subunit and the southernmost fragment of the Tobołw Thrust Sheet in the Bystrica Subunit are prominent. Several folds occur in the studied area. Numerous transverse and oblique faults are also present. The result of the present geological investigations in the study area was the creation of a geological map of the Magura Nappe deposits in the Gorce Mountains. In general, a high-resolution digital elevation model contributed signi.cantly to the progress ARTICLE HISTORY Received 5 May 2020 Revised 17 June 2021 Accepted 18 June 2021 KEYWORDS Gorce Mts; Magura Nappe; stratigraphy; tectonics; high­resolution digital elevation model 1. Introduction The Magura Nappe, located in the Gorce Moun­tains, one of the mountain belts constituting the Polish Outer Carpathians, has not yet been fully investigated. Heretofore, no comprehensive study of lithostratigraphic units has been carried out there, nor have its lithostratigraphic boundaries been correctly de.ned or precisely drawn on geo­logical maps. De.nitions of some individual lithos­tratigraphic divisions have been left open to question; moreover, micropalaeontological studies have presented divergent views on the age of some deposits (Cieszkowski, 1992; Kaczmarek et al., 2016; Oszczypko-Clowes et al., 2018). Use of the formal names of selected lithostratigraphic divisions in the Krynica Subunit as proposed by Birkenmajer and Oszczypko (1989) is problematic, as these names are formally associated with the Bes­kid Sądecki range, where the development of some lithofacies di.ers from that in the Gorces. In pre­vious research, the tectonics of the south-western part of the Gorces were not described in detail (Burtan et al., 1978a, 1978b; Watycha, 1975,p. 1976). Moreover, previous mappings have failed to reconstruct fold structures or faults. Also, the lower range tectonic units have not been properly distinguished in previous studies (Watycha, 1963; Watycha in: Burtan et al., 1978a, 1978b). In the present study, the authors decided to con­duct new, classical geological mapping. The main aim was the construction of a new geological map of the Magura Nappe deposits in the south-western part of the Gorce Mountains. The map was drawn up based on data obtained via accurate geological mapping performed at 1:10,000 scale and acquisition of geological content through the analysis of a high­resolution digital elevation model (DEM). This research delivers new tectonic and lithostratigraphic data of the study area. The criteria adopted for dis­tinguishing various lithostratigraphic units during the .eldwork in the study area will be clearly described. One of the main results presented in the present paper is a geological map on a 1:25,000 scale, complete with geological cross-sections and lithostratigraphic logs ‘Main Map’. This research was primarily focused on Magura Nappe deposits. Great attention was paid during the construction of this map to the clari.cation of the boundaries of lithostratigraphic units. On the map, folds, faults, and thrusts are shown, as well as being detailed on the tectonic sketch (Figure 1). This signi.cant progress in the identi.cation of geological structures was poss­ible thanks to the application of modern geographic information system methods based on a high-resol­ution digital elevation model (DEM) to the classical geological mapping methodology. CONTACT Mateusz Szczęch mateusz.szczech@uj.edu.pl Jagiellonian University, Institute of Geography and Spatial Management, EO-CHANGE Lab., ul. Gronostajowa 7, 30-387 Krak, Poland © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. M. SZCZĘCH AND M. CIESZKOWSKI Figure 1. Tectonic sketch map of the study area. Tectonic sketch map of the study area. The axial planes of the anticlines, syn­clines, thrust of the Krynica Subunit on the Bystrica Subunit, and faults, as well as overturned bedding zone are marked on this sketch. The main tectonic structure names were also placed there. 2. Geological setting The Western Carpathians are subdivided into exter­nides (the Outer Carpathians) and internides (includ­ing the Central and Inner Carpathians; Golonka et al., 2018; Golonka, Pietsch, et al., 2019; Golonka, Waś­ kowska, et al., 2019; Golonka et al., 2020; Książkiewicz, 1977; Plašienka, 2018), both distinctly bounded by the Pieniny Klippen Belt (Figure 2(A,B)). The recent geo­logical structure of the Western Carpathians is a result of plate tectonics which led to a collision of the Central Carpathian, which is part of the Adriatic (Apulian) plate, with the northern European Plate (Golonka, Pietsch, et al., 2019; Golonka, Waśkowska, et al., 2019; Golonka et al., 2020). As part of a subduction process, the European Plate is sliding towards the south beneath the Adriatic (Apulian) Plate (Golonka, Waśkowska, et al., 2019; Golonka et al., 2020). In this location, the Outer Carpathians formed an accre­tionary wedge thrust onto the European Plate. The geological deep structure of the Polish Carpathians is presented on a cross-section along the main geotra­verse between Krakw and Zakopane (Figure 2(A, B)), constructed on the basis of data coming from deep boreholes (up to 5000 m) and seismic data recorded in the last four decades of the twentieth century (e.g. Golonka et al., 2005, 2018, Golonka, Pietsch, et al., 2019; Marzec et al., 2019; Sikora et al., 1980). The Central Carpathians constitute a prolongation of the Eastern Alps (which, taken together, form part of the ALCAPA tectonic plate; e.g. Golonka et al., 2020; Plašienka, 2018), built of Permian–Cretaceous deposits covering an older crystalline bedrock com­posed mainly of granitoids and metamorphic rocks. At the end of the Late Cretaceous, folding and thrust­ing resulted in the creation of a system of nappes. Later, during the Palaeogene, a period of uplifted and eroded orogeny was entered by transgression. This resulted in the sedimentation of several thou­sands of metres of deposits, mainly turbidites (Soták et al., 2001). In general, this post-orogenic sedimen­tary cover is known as the Central Carpathian Palaeogene. The Pieniny Klippen Belt (PKB) is a narrow tec­tonic unit extending from Austria to Romania, along the boundary between the Central and Outer Car­pathians (Birkenmajer, 1986; Golonka et al., 2015, 2018; Golonka, Pietsch, et al., 2019; Golonka, Waś­ kowska, et al., 2019; Golonka et al., 2020; Książkiewicz, 1977; Plašienka, 2018). The Mesozoic–lower Cenozoic sedimentary rocks of the PKB were deposited in the Figure 2. Location of the research area: (A) map of the Outer Western Carpathians in Poland (after Cieszkowski et al., 2017); (B) cross-section A–B through the Western Carpathians (Zakopane–Cracow line after Golonka et al., 2019, simpli.ed). Map presents the polish sector of the Western Carpathians (after Cieszkowski et al., 2017). There are marked the main Carpathians tectonic units with the location of the research area (red box) and with the line of the cross-section Cracow-Zakopane, which is added below the map. The cross-section presents the nappes structure of the Outer Carpathians and their basement, as well as contact with Central Carpathians. palaeogeographic realm of the Alpine Tethys. During the Late Cretaceous–Palaeogene, the sedimentary cover was deformed by orogenic deformations and became part of the accretionary prism formed in front of the advancing ALCAPA (Central Car­pathians) and subsequently incorporated into the Outer Carpathians in the Miocene orogenic phase (Golonka, Waśkowska, et al., 2019). Generally, the PKB is analogous to the klippen zones in the northern Alps of Eastern Austria. The Outer Carpathians, built mainly of thick .ysch successions (up to 6000 m), are also known as the Flysch Carpathians (e.g. Golonka et al., 2005; Golonka, Waśkowska, et al., 2019; Golonka et al., 2020; Książkiewicz, 1977; Ślączka et al., 2006). Their origin is connected with the geological evolution of the northern part of the Alpine Tethys, where several sedi­mentary basins, separated by ridges, were formed. During the Late Jurassic–Early Miocene, these basins were .lled mainly with deep-sea sediments deposited by turbidity currents. The northward movement of the Central Carpathian Plate and the underriding of the European Plate beneath it led to the development of an accretionary wedge and reorganisation of the Outer Carpathian basins during the synorogenic stage. Deposits .lling basins were folded and detached from their basement in the Miocene. These deposits formed a sequence of nappes bounded by thrusts. M. SZCZĘCH AND M. CIESZKOWSKI Together, they overthrusted the consolidated North European Plate, consisting of Precambrian, Palaeo­zoic, and Mesozoic rocks. The platform was underrid­den beneath the Outer Carpathian Plate. In the subduction processes the ridges collapsed; as a result, only basinal deposits were preserved in the nappes. In front of the Outer Carpathian orogenic belt thrust­ing over the North European Platform, the Carpathian Foredeep, .lled with Miocene molasses, was formed (Golonka, Waśkowska, et al., 2019; Ślączka et al., 2006). The Magura Nappe, the largest tectonic unit in the Polish and Slovakian sector of the Outer Carpathians, tectonically adjoins the PKB (e.g. Golonka et al., 2015) to the south, bordering on the Inner Carpathians (Figure 2), and overthrusts northwardly the Dukla, Fore-Magura, and Silesian Nappes. Within the Magura Nappe, four facies-tectonic zones (subunits) can be distinguished (Koszarski et al., 1974). The thicknesses of their sedimentary successions range between 2000 and 5000 m. The Krynica and Bystrica Subunits occur in the Gorce Mountains. The former is spread over the southern and central parts of the studied area, whereas the Bystrica Subunit occupies only a narrow fragment in its northern part. Near the western border of the research area is the Kra­k–Zakopane geological cross-section representing the deep geological structures of the Carpathians and their consolidated basement between the emergence of the European Platform in Krakw and the Inner Carpathians in the Tatra Mountains (Cieszkowski, 2006; Golonka et al., 2005, 2018; Golonka, Pietsch, et al., 2019; Marzec et al., 2019; Sikora et al., 1980). 3. Methods 3.1. Methods and data The geological map of the south-western part of the Gorce Mountains presented here was constructed on the basis of accurate geological investigations, using traditional methods of geological .eld mapping coupled with the interpretation of a high-resolution digital elevation model (DEM). DEMs are successfully used in geological research (Cieszkowski et al., 2017; Lo et al., 2021; Starzec et al., 2018). The .eld work, which enabled direct observations of outcrops, was carried out in 2015–2018. Subsequently, studies were made on the .ysch deposits and on the lithological and sedimentological features of the mapped deposits, in order to better de.ne the stratigraphic boundaries between the several lithostratigraphic units. The mapped tectonic units were also analysed. In locations without outcrops, we attempted to identify the lithos­tratigraphic units by means of a study of the compo­sition of weathering covers. In places with no outcrops, as well as in inaccessible areas, remote sensing methods were of particular importance. In such cases, strati.cation, lithostratigraphic bound­aries, faults, and fractures, thrusts, fold structures, and geomorphological forms were clearly visible where they existed in places with thin and undisturbed weathered covers (Figures 3 and 4; Kania & Szczęch, 2020). 3.2. DEM analyses The high-resolution digital elevation model (DEM) was based on airborne laser scanning (ASL). The stan­dard for this ASL data was an average density of 4–6 points/m2. The working resolution of the DEM was 1 m; the root mean square error of height was <15 cm (Wężyk, 2015). The advantage of this type of DEM is its capacity for the observation of the mor­phology of terrain without vegetation. During a preliminary study, research methods based on a DEM applicable to geological research were selected. Firstly, long, linear forms in slope morphology, i.e. step-like forms (variations in slope inclination; Figure 3), were related to the strati.ca­tions of sandstone-shale deposits or more resistant sandstone layers. Secondly, changes in features such as the density, thickness, and height of the above-mentioned linear forms were associated with various levels of resistance to the erosion of the rock formations and dipping of layers. These obser­vations enabled easier, faster interpretation of the boundaries of each rock formation over long dis­tances (Figures 3 and 4), despite a lack of outcrops in many places. These methods were important e.g. in the correction of the Krynica Subunit trace of the thrust. In the research, the authors used the lineament method, as well as observations of breaks in the mentioned linear forms visible on the materials from the DEM (Figure 3). In the current study, we accepted the de.nition of lineament given by O’Leary et al. (1976) as a linear form in morphology occurring over considerable distances with a high probability of association with a geological structure. Based on the DEM research, a network of linea­ments was obtained and referred to potential faults. Based on the DEM analysis, the detected lineaments were randomly tested in the .eld in order to validate the hypothesis. Field testing allowed us to con.rm most of the interpreted lineaments as faults; the lat-ter faults were identi.ed by the occurrence of such forms as fault throws, fault-drag related folds, frac­tures, melange zones, tectonic breccias, cataclasites, and microbreccias. Many of the identi.ed faults on the DEM would have been impossible to detect based on the .eld mapping investigations alone. The use of DEM-based methods enabled the Figure 3. Hillshade image presenting the eastern slopes of Kiczora Mountain linear forms representing strati.cation of deposits of the Piwniczna Sandstone Member and lineaments where the continuity of layers (steps-like forms) was broken by faults are visible. Image A: without interpretation; B: interpreted. Two pictures of Hillshade images, which present morphology of eastern slopes of Kiczora Mountain. There are visible linear forms, representing strati.cation of deposits of the Piwniczna Sandstone Member and lineaments, where the continuity of layers (steps-like forms) was broken by faults. In the image A there is no interpretation, and in the image B two lineaments are marked by red lines, which show faults. detection of faults, making it possible to revise and correct fault strikes identi.ed in the .eld. 3.3. Geological map construction Field mapping of the southwestern part of the Gorce Mountains was performed at 1:10,000 scale and greater, while the .nal product was returned at a 1:25,000 scale (Figure 4). Field data have been inte­ grated with interpretative geological facts based on DEM analysis. Some geological features interpreted with DEM were compared with real conditions in the .eld and, conversely, some .eld .ndings were checked via DEM. This procedure eliminated many errors and signi.cantly improved the accuracy of the map. With this approach, strike and dip measurements were eliminated in some locations (e.g. within landslides), especially where dips may have been rotated by landslides rather than by fault activity. Additionally, in many inaccessible locations or in sites covered by soil and younger sediments, if strati.cation was visible as the pre­viously mentioned step-like forms, DEM enabled lithostratigraphic boundaries and thrusts to be drawn with great accuracy. As mentioned, the DEM studies and the applied lineament method enabled the identi.cation of numerous new faults not described or marked on previous geological maps. Based on the completed map, geological cross-sections and a tectonic sketch were constructed. 4. Geological mapping results In the study area, four Campanian–Lower Miocene lithostratigraphic formations were distinguished in the Krynica Subunit. The youngest (Lower–Middle Miocene) deposits of the Krynica Subunit are exposed close to, but out of, the study area (Cieszkowski, 1992). Older Cenomanian–Campanian deposits were drilled through by the Obidowa IG-1 deep borehole, located in Rdzawka (2 km west of the research area) and coincident with the Krak–Zakopane cross-section. 4.1. Sedimentary succession of the Krynica Subunit In the studied area, the Campanian–Lower Miocene sedimentary succession of the Krynica Subunit is rela­tively poorly di.erentiated. The Upper Cretaceous– Palaeocene Ropianka and Eocene Beloveža formations stand out clearly in lithological terms (Figure 5). The overlying the Eocene–Oligocene Magura Formation and Upper Eocene–Oligocene Malcov Formation con­sist mainly of thin-and medium-bedded siliciclastic turbidites, although they include intercalations of Magura-like lithotype sandstones as well. The total thickness of these formations is in the range of 3500–4000 m. The Ropianka Formation (Campanian–Palaeo­cene) is represented by thin-and medium-bedded sandstone-shale alternations, developed as classic tur­bidites (Figure 6(A)). Fine-or medium-grained mus­covitic sandstones are intercalated with grey and greenish-grey, more or less marly shales. These depos­its are interbedded with packages of thick-bedded sandstones and conglomerates (Figure 6(B)); the thickest, well exposed in the Obidowiec Ridge, reaches approximately 120 m. The Beloveža Formation (Lower Eocene) consists of thin-and/or medium-bedded shale-sandstone tur­bidites, very rich in trace fossils. Light grey calcareous sandstones are intercalated with bluish-grey marly shales in proportions of 2:1 or 1:1. Within these, deposits occur called the Krynica Sandstone Mem-ber, 30–40 m thick and represented by thick-bedded sandstones and conglomerates, similar to those known from the Magura Formation. M. SZCZĘCH AND M. CIESZKOWSKI Figure 4. Part of the here-presented geological map illustrating observation points measured in the .eld. A: before generalisation; B: after generalisation. There are two images showing a fragment of the geological map. In the .gure A, the documentation map with the observation points of the dip and strike bedding measured in the .eld is presented. The image B presents a geological map with the dip and strike bedding after generalisation. Figure 5. Lithostratigraphical logs of the Krynica Subunit constructed on the base of cross-sections presented on the geological map. There are .ve pictures of the lithostratigraphical logs of the Krynica Subunit constructed on the base of cross-sections pre­sented on the geological map. Figure 6. Field view of the Ropianka Formation deposits: (A) thin-and medium-bedded sandstone-shale .ysch (Lepietnica Stream valley); (B) thick-bedded sandstones (Obidowiec Ridge). Two pictures (A,B) present the .eld view of Ropianka Formation deposits. In the picture A, the thin-and medium-bedded sandstone-shale .ysch is visible (Lepietnica Stream valley). The layers of the sand­stones are brighter grey weathered, while the shales are grey or dark grey in colour. Picture B presents a rock tour built of thick­bedded sandstones (Obidowiec Ridge). The thickness of the sandstone layers is 1–1.5 m. The sandstones are parallel laminated. The Magura Formation (Lower Eocene–Lower Oligocene), although characterised by great thickness, is dominated by thick-bedded sandstones of the ‘Magura sandstone’ lithotype (Figure 5), and subor­dinately by conglomerates. The sandstones are more or less calcareous, bluish-grey or grey in colour, or yel­lowish-grey when weathered. One feature that allows researchers to clearly distinguish sandstones and con­glomerates embedded in the Magura Formation is the presence of red and pink grains (i.e. pink quartz and feldspars, red quartzitic sandstones, and porphyry­like volcanic rocks – see Figure 7(B)). The presence or absence of intercalations of other lithological types of deposits between thick-bedded sandstones enabled the distinction of three lithostrati­graphic members within the Magura Formation (Figure 7(A)). The Piwniczna Sandstone Member (Lower–Middle Eocene) is represented by thick­bedded sandstones, conglomeratic sandstones, and conglomerates intercalated with thin-and medium­bedded shale-sandstone packages, developed as Belo­veža Formation-like facies (Figure 7(C)). The thick­bedded sandstones deposits of the Kowaniec Member (Middle–Upper Eocene) are characterised by the occurrence of layers of coarsely cleavable, calcite­free, green mudstones, thin-bedded shale-sandstone packages, and single intercalations of thick-bedded, massive grey, marly turbidites known as Łącko Marls. The Poprad Sandstone Member (Upper Eocene) is built almost entirely of thick-bedded Magura sandstones (Figure 6(B)) and reaches 1000– 1200 m thickness in the Gorces (Figure 5). The Malcov Formation (Oligocene–Lower Mio­cene) consists of medium-and thin-bedded sand­stone-shale deposits, nearly all calcareous (Figure 8 (C)). Occasional intercalations of massive green shales or grey-yellowish and bluish soft marls occur, some­times as much as several metres thick. Moreover, a substantial part of this formation comprises packages of medium-and thick-bedded Magura sandstone­like lithotype. At the top of the formation, these thick-bedded sandstones constitute the Waksmund Sandstone Member. 4.2. Sedimentary succession of the Bystrica Subunit North of the studied area, the most complete pro.le of Cenomanian–Oligocene deposits of the Bystrica Sub-unit crops out (e.g. Burtan et al., 1978a, 1978b; Szczęch et al., 2016). In the studied area, the Bystrica Subunit is represented solely by the Magura Formation (Middle Eocene–Oligocene), compounded of several members (according to Cieszkowski, 2006; Oszczypko, 1991; Szczęch et al., 2016). The Maszkowice Sandstone Member (Middle Eocene) is represented by the thick-bedded ‘Magura sandstone’ lithotype, with rare intercalations of thin-bedded sandstone-shale deposits similar to those of the Beloveža Formation. The Mniszek Shale Member (Middle Eocene) is built only of thin-and medium-bedded sandstone­shale deposits similar to those of the Beloveža For­mation. The lower part of this member is marked by the occurrence of several metre-thick variegated shales. Above this is the Trusika Member (Upper Eocene), represented by a thick-bedded ‘Magura sandstone’ lithotype intercalated occasionally by dark grey to grey shale or sandstone-shale deposits similar to those of the Beloveža Formation. The youngest Poprad Sandstone Member (Upper Eocene–Oligocene) is similar to the Poprad Sandstone Member from the Krynica Subunit; however, the grains in the thick-bedded sandstone are usually .ner. 4.3. Quaternary deposits In the research area, Quaternary deposits are rep­resented mainly by .uvial deposits accumulated in narrow, deeply indented V-shaped valleys. The thick­ness of the .uvial deposits is from 0.5 to 5 m M. SZCZĘCH AND M. CIESZKOWSKI Figure 7. Field view of the Magura Formation deposits: (A) thick-bedded sandstones of the Piwniczna Sandstone Member (Białe Skały, the northern slopes of Gorc Troszacki Ridge); (B) conglomeratic sandstones of the Magura sandstone lithotype with charac­teristic red grains; (C) thin-bedded sandstone-shale folded deposits of Beloveža-like beds, intercalated with thick-bedded sand­stones – Piwniczna Sandstone Formation (Łopuszna Valley). Field view of the Magura Formation deposits. In the picture A is a rock tore built of thick-bedded sandstones of the Piwniczna Sandstone Member (Białe Skały, the northern slopes of Gorc Troszacki Ridge). The sandstone layers are 0.5–3.0 m thick amalgamated, massive poorly sorted. The parallel and cross lamination is obser­vable in some layers. In the pictures are conglomeratic sandstones of the Magura sandstone lithotype with characteristic red and pink grains of feldspar (orthoclase), quartz, quartzitic sandstones and some volcanic rocks. In the image C are thin-bedded sand­stone-shale folded deposits of Beloveža-like beds, intercalated with thick-bedded sandstones – Piwniczna Sandstone Formation (Łopuszna Valley). (Watycha, 1976; Zuciewicz, 1998). Only in the south­ernmost part of the research area in the Orava-Nowy Targ Basin does the thickness of the quaternary depos­its grow to about 10 m (Watycha, 1976). These depos­its are represented mainly by gravels, with sands and muds built from .ysch material also occurring. In the Orava-Nowy Targ Basin, pebbles of the Tatra material dominate in the gravel composition. To the west of Nowy Targ, about 4 m thick of yellow alluvial clay was accumulated on the .uvial material (Waty­ cha, 1978). On the clays, a raised bog was developed. The slopes in the Gorce Mountains are covered with a thin watershed, the thickness of which ranges from 0.25 to 2 m, occasionally thicker. The common forms in the studied area are landslides. These forms have dimensions of about 200 × 300 m but the biggest landslides located on the southern slopes of Mt Kudłoń. have dimensions of 2×1km. 4.4. Tectonics Two tectonic units occur in the investigated area in the Krynica Subunit: the Turbacz and the Kudłoń Thrust Sheets (newly distinguished by the authors) (Figure 1). Also, the ‘Peri-Klippen Fold Zone’ thrust sheet divided by Watycha (1975, 1976) in the southern part of the study area was included in the Turbacz Thrust Sheet. The authors of this publication (Watycha, 1975, 1976) identi.ed a normal sedimen­tary transition between the Magura and Malcov for­mations at the site of the alleged thrust. What is more, recent micropalaeontological dating (Ciesz­ kowski, 1992; Cieszkowski & Olszewska, 1986; Kacz­ marek et al., 2016; Oszczypko-Clowes et al., 2018) showed that the deposits described by Watycha (1975, 1976) as Cretaceous deposits of the Ropianka Formation, located in the frontal part of the ‘Peri-Klippen Fold Zone’, are by contrast younger and referable to the Oligocene-Miocene deposits of the Malcov Formation. The Turbacz Thrust Sheet over­thrusts the Kudłoń Thrust Sheets; both overthrust the Bystrica Subunit, represented here by the south­ernmost structural element of the Tobołw Thrust Sheet. The sedimentary deposits of the Krynica Subunit are folded and cut by numerous faults. The folds, with the exception of the Rdzawka-Ponice Anticline (Figure 1), are characterised by rather small ampli­tudes in the studied area. Most are mesoscopic folds, and it is di.cult to track the traces of their axes over great distances. Only some are macro­scopic folds with axes that can be traced for a long distance (e.g. the Sieniawa Syncline, the Pyzka Anticline, and the Rdzawka-Ponice Anticline – Figure 1). Figure 8. Field view of the Magura Formation deposits: (A) thick-bedded sandstones intercalated with thin-and medium-bedded .ysch layers characteristic of the Kowaniec Member of the Magura Formation (Ochotnica, Furcka Stream); (B) quarry of the Magura Sandstone-Poprad Sandstone Member in the village of Klikuszowa; (C) thin-and medium-bedded sandstone shale .ysch of the Malcov Formation (Samorody, Nowy Targ). Field view of the Magura Formation deposits. In the image A are thick-bedded sandstones intercalated with thin-and medium-bedded .ysch layers characteristic of the Kowaniec Member of the Magura Formation (Ochotnica, Furcka Stream). The sandstone layers are about 0.5 m thick. The shales are grey and bright grey. In the picture B the quarry of the Magura Sandstone-Poprad Sandstone Member in the village of Klikuszowa is visible. In this locality can observe the Magura sandstones of several hundred metres thick, which is almost completely devoid of shale inter­calations. In the picture C is an outcrop of the Malcov Formation with steeply dipping layers of thin-and medium-bedded sand­stone-shale turbidites, with intercalation of the thick-bedded sandstones (Samorody in Nowy Targ). Numerous transverse and oblique faults – usually strike-slip or oblique-strike – with various lengths, throws, and strike orientations occur in the study area. Two zones with di.erently oriented fault strikes can be oriented: a western sector, dominated by faults with strikes NNW–SSE and NNE–SSW, and an east­ern sector, with dominating strikes oriented NNW– SSE, NNE–SSW, and NE–SW (Kania & Szczęch, 2020). Occasionally ENE–WSW fault strikes have also been observed. Some faults form complex dislo­cation zones 5–10 km long, or even longer. Examples are the dextral strike-slip of the Waksmund-Ponice Fault Zone (Figure 1), which is oriented NNW–SSE and extends to the Skawa River Fault Zone, also cut­ting across other subunits of the Magura Nappe (Książkiewicz, 1977); the dextral strike-slip of the Orava Fault Zone with the Lepietnica Fault, extend­ing NE–SW; or the meridian Ostrowsko-Maniowy M. SZCZĘCH AND M. CIESZKOWSKI Fault Zone which is the oblique fault system, of unclear kinematics (Figure 1). 5. Discussion The main problems identi.ed during the work on the south-western part of the Gorce Mountains concerned the course of lithostratigraphic boundaries and the de.nition of lithostratigraphic units as well as tectonic structures. Tracing the boundaries on the map between the various lithostratigraphic units of the Krynica Subunit on the map in the studied area was di.cult. The identi.cation of lithostratigraphic members of the Magura Formation was particularly di.cult, due mainly to the dominance of thick-bedded ‘Magura sandstones’ lithotypes; only the inherent thin inter­beddings of other lithotypes enabled individual mem-bers to be distinguished (Burtan et al., 1978b; Watycha, 1975). DEM projections were very useful in plotting unit boundaries, improving the results from .eld-only evidence. In formalising the lithostratigraphic nomenclature of the Krynica Subunit sedimentary succession, Bir­ kenmajer and Oszczypko (1989) distinguished the Upper Cretaceous–Palaeocene deposits, previously known as ‘the Szczawnica beds’, under the formal name ‘the Szczawnica Formation’. Chrustek et al. (2005), among others, conducted in-depth studies on the Szczawnica Formation. According to the latter authors, the lithologic and sedimentary features of this unit do not di.er from those of the Ropianka For­mation, which is widespread in the Bystrica and Rača subunits (e.g. Książkiewicz, 1977; Oszczypko, 1991; Oszczypko, Malata, et al., 2005). Oszczypko-Clowes et al. (2018) stated in their research that parts of the deposit incorporated in the Szczawnica Formation, even within its stratotype area, are much younger, dat­ing from the Miocene. However, in our opinion, the traditional name of the Ropianka Formation should be reverted. This allows for better ful.lment of the Stratigraphic Code, providing better consistency. In the research area, the possibility of the Beloveža Formation being distinguished is due to the fact that it occurs here in the northern, most distal part of the Krynica Subunit, preserved in the northern limb of the Rdzawka-Obidowiec anticline. In the more internal zones of the Krynica Subunit, also in the southern limb of the previously mentioned Rdzawka-Obidowiec anticline, this formation is replaced by the deposits of the Piwniczna sandstone member, which is a result of the overlapping facies. The relationship between the Beloveža Formation and the Piwniczna sandstone member may emphasise the occurrence in the Piwniczna sandstone member intercalations of the thin-bedded packets of sandstone-shale deposits of the Beloveža Formation lithotype. Studies carried out in the SW part of the Gorces proved the importance of correct micropalaeontologi­cal dating of lithostratigraphic divisions. Inaccurate micropalaeontological dating of .ysch deposits can lead to signi.cant errors, even in the interpretation of tectonics, as exempli.ed by the distinction by Waty-cha (1975, 1976) of the thrust sheet called the Peri-Klippen Fold Zone. The detrital material characterising the studied lithostratigraphic units was derived from turbidity currents and deposited in the proximal and, partly, central sector of the southern Magura Basin (Oszc­ zypko et al., 2015, 2016). The material was sourced from an emergent ridge bordering the basin to the south and formed an extensive submarine lobe system (Dirnerová & Farkašovsk, 2018; Oszczypko, Oszc­ zypko-Clowes, et al., 2005). The style of fold tectonics in the Krynica Subunit may be caused here by the dominance of thickly­bedded sandstones. These massive sandstones charac­terise about 2000 m of the Magura Formation (Figure 5) and their presence reduced the susceptibility to pro-duce classic folded deformations, known from other areas in the Magura Nappe (e.g. Książkiewicz, 1977). The dense network of faults is compatible with the general Western Carpathian system (Kania & Szczęch, 2020). The authors noted that the layers of the Krynica Subunit were characterised by relatively steep dips. Additionally, this subunit included zones of over­turned layers dipping to the north. Here, this phenom­enon is associated with a .ower structure formed within a collision zone of tectonic plates (Cieszkowski, 2006; Golonka et al., 2005; Golonka, Pietsch, et al., 2019; Marzec et al., 2019). The structural basement of the Magura Nappe in the Gorce region forms the Grybw and Dukla Nappes, both drilled through by deep boreholes in the western periphery of the Gorce Mountains (Cieszkowski, 2006; Golonka et al., 2005, 2018; Golonka, Pietsch, et al., 2019). The analy­sis of boreholes and geophysics allowed us to estimate the thickness of the Magura Nappe, ranging between 2000 and 4000 m. A platform consolidated basement was identi.ed here at depths ranging between 7000 and 9000 m. 6. Conclusions A new detailed geological map of the south-western part of the Gorce Mountains, on a 1:25,000 scale ‘Main Map’, was produced after .eld mapping and analysis of a high-resolution DEM. In the study area, two lower-range tectonic struc­tures of the Krynica Subunit occur; the Turbacz Thrust Sheet and the Kudłoń Thrust Sheet. Furthermore, the southernmost part of the Tobołw Thrust Sheet belonging to the Bystrica Subunit was mapped. The outcropping sedimentary succession of the Krynica Subunit, reaching approximately 4000 m in thickness and largely or totally dominated by thick­bedded sandstones, is represented by four formations, Late Cretaceous–Early Miocene in age. These are the Ropianka, Beloveža, Magura, and Malcov Formations, within which several lithostratigraphic members have been distinguished. By contrast, the Bystrica is here represented only by the Magura Formation. In the Gorces, the fold tectonics style of the Krynica Subunit di.ers from other areas of the Magura Nappe, being mainly made of folds characterised by relatively short lengths and low amplitudes. The subunit is also characterised by a dense network of transverse and oblique faults, usually strike-slip or oblique-slip. Occasionally, faults are linked, forming longer dislo­cation zones, which extend in some places beyond the study area. Software The geological map of the south-western part of the Gorces and cross-sections were prepared with the use of ArcMap 10.4. The analysis of digital elevation models was conducted with the use of Relief Visualiza­tion Toolbox, version 1.3 (Kokalj & Somrak, 2019; Zakšek et al., 2011). The lithostratigraphic logs were created in CorelDRAW. Acknowledgements We would like to thanks to reviewers, for their remarks, which helped to improve the paper signi.cantly. Our thanks go also to Dr Maciej Kania and Dr Kassandra Papadopoulou for valuable suggestions. Disclosure statement No potential con.ict of interest was reported by the author (s). Funding This work was supported by Institute of Geography and Spatial Management [Grant Number N23/DBS/00014]. References Birkenmajer, K. (1986). Stages of structural evolution of the Pieniny Klippen Belt, Carpathians. Studia Geologica Polonica, 88,7–32. Birkenmajer, K., & Oszczypko, N. (1989). Cretaceous and Paleogene lithostratigraphic units of the Magura Nappe, Krynica subunit, Carpathians. Annales Societatis Geologorum Poloniae, 59(1-2), 145–181. Burtan, J., Paul, Z., & Watycha, L. (1978a). Objaśnienia do Szczegłowej Mapy Geologicznej Polski 1:50000, Arkusz Mszana Gna. Wydawnictwa Geologiczne.. Burtan, J., Paul, Z., & Watycha, L. (1978b). Szczegłowa Mapa Geologiczna Polski 1:50000, Arkusz Mszana Gna. Wydawnictwa Geologiczne. Chrustek, M., Golonka, J., Janeczko, A., & Stachyrak, F. (2005). Geological characterisation of the Krynica Subunit in the vicinity of Krościenko on the Dunajec river (Magura Nappe, Outer Flysch Carpathians). Kwartalnik AGH. Geologia, 31(1), 127–144. Cieszkowski, M. (1992). Marine Miocene deposits near Nowy Targ, Magura Nappe, Flysch Carpathians (South Poland). Geologica Carpathica, 43(6), 339––3346. Cieszkowski, M. (2006, April 19–22). Structures of the Flysch Carpathians between NowyTarg and Rabka. Proceedings of the 4th Meeting of the Central European Tectonic Studies Group/11th Meeting of the Czech Tectonic Studies Group/7th Carpathian tec­tonic Workshop, Geolines, 20, 173–176, Zakopane, Poland. Cieszkowski, M., Kysiak, T., Szczęch, M., & Wolska, A. (2017). Geology of the Magura Nappe in the Osielec area with emphasis on an Eocene olistostrome with meta­basite olistoliths (Outer Carpathians, Poland). Annales Societatis Geologorum Poloniae, 87(2), 169–182. https:// doi.org/10.14241/asgp.2017.009 Cieszkowski, M., & Olszewska, B. (1986). Malcov beds in the Magura Nappe near Nowy Targ, Outer Carpathians, Poland. Annales Societatis Geologrum Poloniae, 56(1-2), 53–71. Dirnerová, D., & Farkašovsk, R. (2018). Sedimentary record comparison of the Piwniczna and Poprad sand stones (Magura unit, Outer Carpathians) – a study from the borderarea of eastern Slovakia and Poland. Geological Quarterly, 62(4), 881–895. https://doi.org/10. 7306/gq.1445 Golonka, J., Aleksandrowski, P., Aubrecht, R., Chowaniec, J., Cieszkowski, M., Florek, R., Gawęda, A., Jarosiński, M., Kępińska, B., Krobicki, M., Lefeld, J., Lewandowski, M., Marko, F., Michalik, M., Oszczypko, N., Picha, F., Potfaj, F., Słaby, E., Ślączka, A., … Żelaźniewicz, A. (2005). The Orava deep drilling project and post-paleogene tectonics of the Northern Carpathians. Annales Societatis Geologorum Poloniae, 75(3), 211–248. Golonka, J., Gawęda, A., & Waśkowska, A. (2020). Carpathians. In Reference module in Earth systems and environmental sciences. Elsevier. https://doi.org/10.1016/ B978-0-12-409548-9.12384-X. Golonka, J., Krobicki, M., Waśkowska, A., Cieszkowski, M., & Ślączka, A. (2015). Olistostromes of the Pieniny Klippen Belt, Northern Carpathians. Geological Magazine, 152(2), 269–286. https://doi.org/10.1017/ S0016756814000211 Golonka, J., Pietsch, K., & Marzec, P. (2018). The North European Platform suture zone in Poland. Geology, Geophysics & Environment, 44(1), 5–16. https://doi.org/ 10.7494/geol.2018.44.1.5 Golonka, J., Pietsch, K., Marzec, P., Kasperska, M., Dec, J., Cichostępski, K., & Lasocki, S. (2019). Deep structure of the Pieniny Klippen Belt in Poland. Swiss Journal of Geosciences, 112(2-3), 475–506. https://doi.org/10.1007/ s00015-019-00345-2 Golonka, J., Waśkowska, A., & Ślączka, A. (2019). The Western Outer Carpathians: Origin and evolution. Zeitschrift der Deutschen Gesellschaft fr M. SZCZĘCH AND M. CIESZKOWSKI Geowissenschaften, 170(3–4), 229–254. https://doi.org/10. 1127/zdgg/2019/0193 Kaczmarek, A., Oszczypko-Clowes, M., & Cieszkowski, M. (2016). Early Miocene age of the Stare Bystre Formation based on calcareous nanofossils (Magura Nappe, Outer Carpathians, Poland). Geological Quarterly, 60(2), 341–354. https://doi.org/10.7306/gq. Kania, M., & Szczęch, M. (2020). Geometry and topology of tectonolineaments in the Gorce Mts. (Outer Carpathians) in Poland. Journal of Structural Geology, 141. https://doi. org/10.1016/j.jsg.2020.104186 Kokalj, Ž, & Somrak, M. (2019). Why Not a single image? Combining visualizations to facilitate .eldwork and On-screen mapping. Remote Sensing, 11(7), 747. https:// doi.org/10.3390/rs11070747 Koszarski, L., Sikora, W., & Wdowiarz, S. (1974). The Flysch Carpathians. Polish Carpathians. In M. Mahel (Ed.), Tectonics of the Carpathian–Balkan Regions, explanations to the tectonic map of the Carpathian-Balkan Regions and their Foreland (pp. 180–197). Štátny geologický tav Diona Šta. Książkiewicz, M. (1977). The tectonics of the Carpathians. Geology of Poland, Vol. 4. Tectonics. The Alpine tectonic epoch. Geological Institute. 476–608 Lo, P.-C., Lo, W., Wang, T.-T., & Hsieh, Y.-C. (2021). Application of geological mapping using airborne-based LiDAR DEM to Tunnel engineering: Example of Dongao Tunnel in Northeastern Taiwan. Applied Sciences, 11(10), 4404. https://doi.org/10.3390/ app11104404 Marzec, P., Golonka, J., Pietsch, K., Kasperska, M., Dec, J., Cichostępski, K., & Lasocki, S. (2020). Seismic imaging of mélanges – Pieniny Klippen Belt case study. Journal of the Geological Society, 177(3), 629–646. https://doi. org/10.1144/jgs2018-220 O’Leary, D. W., Friedman, J. D., & Pohn, H. A. (1976). Lineament, linear, lineation: Some proposed new stan­dards for old terms. Geological Society of America Bulletin, 87(10), 1463–1469. Oszczypko-Clowes, M., Oszczypko, N., Piecuch, A., Sotak, J., & Boratyn, J. (2018). The Early Miocene residual .ysch basin at the front of the Central Western Carpathians and its palaeogeographic implications (Magura Nappe, Poland). Geological Quarterly, 62(3), 597–619. https://doi.org/10.7306/gq.1425 Oszczypko, N. (1991). Stratigraphy of the Paleogene depos­its of the Bystrica Subunit (Magura Nappe, Polish Outer Carpathians). Bulletin of Polish Academy of Sciences, Earth Sciences, 39(4), 433–445. Oszczypko, N., Malata, E., Bąk, K., Kędzierski, M., & Oszczypko-Clowes, M. (2005). Lithostratigraphy and biostratigraphy of the Upper Albian–Lower/Middle Eocene .ysch deposits in the Bystrica and Rača subunits of the Magura Nappe (Beskid Wyspowy and Gorce Ranges; Poland). Annales Societatis Geologorum Poloniae, 75(1),27–69. Oszczypko, N., Oszczypko-Clowes, M., Golonka, J., & Marko, F. (2005). Oligocene-Lower Mio cene se quences of the Pieniny Klippen Belt and adjacent Magura Nappe between Jarabina and the Poprad River (East Slovakia and South Po land): their tectonic position and palaeo­graphic implications. Geological Quarterly, 49(4), 379– 402. Oszczypko, N., Salata, D., & Konečny, P. (2016). Age and provenance of mica-schist pebbles from the Eocene conglomerates of the Tylicz and Krynica Zone (Magura Nappe, Outer Flysch Carpathians). Geologica Carpathica, 67(3), 260–274. https://doi.org/10.1515/ geoca-2016-0017 Oszczypko, N., Ślączka, A., Oszczypko-Clowes, M., & Olszewska, B. (2015). Where was the Magura Ocean. Acta Geologica Polonica, 65(3), 319–344. https://doi.org/ 10.1515/agp-2015-0014 Plašienka, D. (2018). Continuity and episodicity in the Early Alpine tectonic evolution of the Western Carpathians: How large-scale processes Are expressed by the orogenic architecture and rock record data. Tectonics, 37(7), 2029–2079. https://doi.org/10.1029/ 2017TC004779 Sikora, W., Borysławski, A., Cieszkowski, M., Gucik, S., & Jasionowicz, J. (1980). Przekrj geologiczny Krakw – Zakopane. Wydawnictwa Geologiczne. Ślączka,A.,Kruglov,S.,Golonka,J.,Oszczypko,N.,& Popadyuk,I.(2006). Geology and hydrocarbon resources of the Outer Carpathians Poland, Slovakia, Ukraine, general Geology. In J. Golonka & F. Picha (Eds.), The Carpathians and their foreland: Geology and hydrocarbon resources.AAPGMemoir, 84, 221– 258. Soták, J., Pereszlenyi, M., Marschalko, R., Milicka, J., & Starek, D. (2001). Sedimentology and hydrocarbon habi­tat of the submarine-fan deposits of the Central Carpathian Paleogene Basin (NE Slovakia). Marine and Petroleum Geology, 18(1), 87–114. https://doi.org/10. 1016/S0264-8172(00)00047-7 Starzec, K., Sznabel, W., Neubauer, F., Brendel, U., & Friedl, G. (2018). Application of the high-resolution, LIDAR based DEM to identifying tectonic features, case studies from the Polish Outer Carpathians. In Geologica Balcanica, XXI international congress of the Carpathian Balkan geological association (CBGA), September 10-13 2018. University of Salzburg. Abstracts, p. 212. Szczęch, M., Cieszkowski, M., Chodyń, R., & Loch, J. (2016). Geotouristic values of the Gorce National Park and its surroundings (The Outer Carpathians, Poland). Geotourism, 44–45(1), 27–44. https://doi.org/10.7494/ geotour.2016.44-45.27 Watycha, L. (1963). Magura .ysch of the southern part of the Gorce Mts. Przegląd Geologiczny, 11(8), 371–378. Watycha, L. (1975). Szczegłowa Mapa Geologiczna Polski 1:50,000. Arkusz Nowy Targ. Wydawnictwa Geologiczne. Watycha, L. (1976). Objaśnienia do Szczegłowej Mapy Geologicznej Polski 1:50000, Arkusz Nowy Targ. Wydawnictwa Geologiczne. Watycha, L. (1978). Objaśnienia do Szczegłowej Mapy Geologicznej Polski 1:50000, Arkusz Czarny Dunajec. Wydawnictwa Geologiczne. Wężyk, P. (2015). Manual for participants of LiDAR pro­ducts applications training [in Polish] (2nd ed.). Głny Urząd Geodezji i Kartogra.i. Zakšek, K., Oštir, K., & Kokalj, Ž.(2011). Sky-view factor as a relief visualization technique. Remote Sensing, 3(2), 398–415. https://doi.org/10.3390/rs3020398 Zuchiewicz, W. (1998). Ukształtowanie terenu i charakter­ystyka geomorfologiczna trenu na obszarze GPN i jego otoczenia. In Cieszkowski M., Oszczypko N., Polak A., & Zuchiewicz W. (Eds.), Operat ochrony zasobw i walorw przyrody nieożywionej i gleb w Gorczańskim Parku Narodowym (pp. 14–25). Archiwum Gorczańskiego Parku Narodowego.