86(1993) i S.133-14Ü | Wien, August-9:-;! Slovakia Carpathians Pieniny Klippen Belt Jurassic Cretaceous The Czorsztyn Submarine Ridge c w. ^f^» J *•» Synsedimentary tectonics (Jurassic-Lower Cretaceous, Pieniny Klippen Belt): An Example of a Pelagic Swell MILAN MisfK*) 1 Text-Figure, 1 Table, 2 Plates Contents Zusammenfassung 133 Abstract 133 1. Introduction 133 2. The Czorsztyn Pelagic Swell 134 2.1. General Characteristic 134 2.2. Scarp Breccias 134 2.3. Neptunic Dykes 135 2.4. Hiatuses 135 2.5. Hardgrounds 135 3. Differences of Coeval Carbonate Platforms 136 4. Conclusions 136 Acknowledgements 136 References 140 Der submarine Czorsztyn-Rücken (Jura-Unterkreide, Pieniny-Klippengürtel): Beispiel einer pelagischen Schwelle Zusammenfassung Die submarine Czorsztyn Schwelle erstreckt sich über ungefähr 500 km. Während des Jura und der Unterkreide war sie von einer ausge­ dünnten pelagischen Karbonatserie mit einigen Hardgrounds bedeckt. Synsedimentäre Tektonik wird durch Störungsbreccien und zahlrei­ che Gänge belegt. Der Czorsztyn Rücken wurde im Norden durch den Magura-Trog und im Süden durch den Kysuca-Pienninischen Trog begrenzt. Die Sedimente dieser Schwelle unterscheiden sich von den gleichzeitig gebildeten Plattformkarbonaten durch das völlige Fehlen von Algen, Oolithen und Foraminiferen wie z.B. Protopenerophis und Conicospirillina. Abstract The Czorsztyn submarine elevation exhibited a striking extension of about 500 km. During the Jurassic and Early Cretaceous, it was covered by predominantly pelagic condensed carbonate sediments containing hardgrounds. Synsedimentary tectonics are documented by scarp breccias and abundant neptunic dykes. The Czorsztyn ridge was bordered by the Magura trough in the north and by the Kysuca- Pieniny trough in the south. The sediments of this swell differ from those of coeval carbonate platforms by the total lack of algae, oolites and foraminifera such as Protopenerophis and Conicospirillina. 1. Introduction recent analogies. A generalized description of such pelagic Pelagic swells were the characteristic structures sited sw^s was 9jYen bV GARCIA-HERNANDEZ et al. (1988), based along passive continental margins during the Mesozoic. on the cases from penbeticum and Subbeticum in Spam. These relatively narrow, several hundred kilometers long According to these authors the characteristic features of elevations ran parallel to the ancient shoreline. They were Pelagic swells are the following: bordered on both sides by troughs with deep-water se- 1) a considerable amount of pelagic sediments but of minor dimentation. Their interpretation is hindered by the lack of thickness; *) Author's address: Prof. RNDr. MILAN MISI'K, DrSc, Department of Geology and Paleontology, J.A. Comenius University, Mlynskä doli- naG, SK-84215 Bratislava, Slovakia. 134 M.MlSlK 2) a lack of terrigenous elastics; The Czorsztyn sedimentation zone was strongly tecton- 3) abundant condensed facies of mainly red nodular lime­ ized forming some hundred tectonic lenses - so-called klip- stones; pen during the Tertiary. 4) hiatuses accompanied by hardgrounds with pelagic The pelagic swells of the Tethys represent the separated stromatolites; parts of the fragmented margins of the Triassic carbonate 5) synsedimentary tectonics documented by scarp brec­ platforms. As for the Czorsztyn elevation, this cannot be cias and neptunic dykes; their fillings sometimes docu­ directly proved because of the perfect decollement of ment the tilting of blocks. the crystalline + Paleozoic + Triassic complexes from the Jurassic + Cretaceous strata that took place before the nappe stacking and following boudinage. In spite of the ab­ sence of Triassic rocks in the exposed stratigraphic column, 2. The Czorsztyn Pelagic Swell the occurrence of small clasts of dolomite in crinoidal lime­ stone of the Dogger supports the idea that the Czorsztyn 2.1. General Characteristics elevation was a former part of a Triassic carbonate plat­ All the features cited can be observed on the Czorsztyn form. submarine elevation (ANDRUSOV, 1965; BIRKENMAJER, 1963) As in other pelagic swells, siliciclastic sediments are abs­ that extended over a distance of some 500 kilometres dur­ ent in the Czorsztyn succesion, a slight sandy admixture is ing the Jurassic and Early Cretaceous. It can be traced from present only in the Upper Liassic and Dogger limestones. West Slovakia, via South Poland to the Carpathian Ukraine The succession of the Czorsztyn domain consists of crinoid­ (Text-Fig. 1). al limestones of Dogger and Berriasian-Hauterivian age, of The Czorsztyn ridge was bordered on both sides by limestones with dominating pelagic microfauna (Callo- troughs with deep-water sedimentation (including radio- vian-Oxfordian, Kimmeridgian, Tithonian), of coquina lime­ larites) underlain with oceanic or extremly thinned contin­ stones (the so-called Rogöznik coquina of Oxfordian to Ti­ ental crust. The Magura trough was situated to the north and thonian age), of red nodular limestones ranging from Lower the Kysuca-Pieniny trough towards the south. The Czorsz­ Bathonian to Lower Tithonian (RAKÜS, 1990) and exception­ tyn elevation caused several difficulties during the compila­ ally of bioherm limestones known only from a small area near tion of paleogeographic maps of the large area between the Vrsatec (MISI'K, 1979). Alps and the Caucasus (IGCP No. 197, DERCOURT et al., 1990). It was not possible to omit this narrow zone of contin­ ental crust not even at the scale 1 : 10,000.000 and put in­ 2.2. Scarp Breccias stead of it something like a common Magura-Pieniny Scarp breccias accompanied by neptunic dykes were ocean. evidently caused by synsedimentary faults. At the locality HARDGROUNDS IN CZORSZTYN UNIT P 0 L A N 0 ^.. \ . faB_HALKA-CZ0RSZTYN S02=FeA »JKAMENICA L 0 V A K I A <L < < MnFe = ferro-manganese crusts (CaUwian-Oxfordion) J* SiOj ~ silcret crusts [Upper Berrisian and undated) F$£ =: ferric crust (Upper Bathonian) F^ = terric crust (Altaian] NEPTUNIC DYKES IN CZORSZTYN UNIT P 0 CERVEN' VRSATEC: KRIVOKLAT-^Sj DRIEftOVAr ' , BOLESOVSKA D0LINA KRASIN-OOL.SI Text-Fig. 1. Localities with hardgrounds and neptunic dykes in the Czorsztyn unit, Pieniny Klippen Belt. The Czorsztyn Submarine Ridge (Jurassic-Lower Cretaceous, Pieniny Klippen Belt): An Example of a Pelagic Swell 135 Table 1. Timing of neptunian dykes and pocket fillings in the area of the Czorsztyn submarine swell. SENONIAN ALBIAN NEOCOMIAN U.TITHONIAN KIMMERIDGIAN OXFORDIAN CALLOVIAN DOLNY MLYN NEOCOMIAN -VRSATEC KAMENICA LITMANOVA S U.TITHONIAN BABINA LED.NICA VRSATEC VRSATEC Kl MMERI DGIAN DYKE Y B OXFORDIAN T VRSATE C KRASIN CALLOVIAN KYJOV MESTECKO CU BABINA S KRASIN KYJOV BATHONI AN KYJOV DRIEN0VÄ ROCK 1VRSATEC i | KRIVOKLÄT | BAJ 0 C1 AN VRSATEC VRSATEC BABINA BOLESOV VRSATEC MESTECKO Krasin (Text-Fig. 1) the breccias are of Middle Jurassic age Upper Tithonian (PI. 1 -C), furthermore, the Albian sediments and consist of fragments and blocks of various crinoidal penetrated as neptunic dykes and pockets in the Callov­ limestones up to 1 m. At the locality Kyjov (Text-Fig. 1) the ian-Oxfordian, Bajocian and Bathonian layers. Such a per­ breccias originated in the Upper Jurassic. They are formed fect submarine erosion of all Barremian and Aptian sedi­ by fragments of various limestones of Dogger and Malm. ments seems improbable. The Albian transgression began Meter-sized caverns filled with laminated limestone with a with red marls containing pelagic foraminifers. The cause of pelagic microfauna of Kimmeridgian and Tithonian age give it could be a sudden collapse of the seashore or an ingres- further evidence of the existence of submarine fault scarps. sion after the break of a neck. Another emersion could be The latest activity of synsedimentary faulting is documented supposed in the area of Oxfordian bioherms at Vrsatec. by the youngest neptunic dykes filled with white Berriasian They contain voids enlarged by dissolution (PI. 1-D) and limestones containing Calpionella alpina LORENZ. filled by crystal silt considered as evidence of meteoric dia- genesis. A small calcrete fragment was found in a neptunic dyke near Bolesov. The dissolution of aragonitic bivalve 2.3. Neptunic Dykes shells (PI. 2-A) was previously considered as meteoric dia- genesis. According to SANDBERG (1985) and PALMER et al. Neptunic dykes and sills are also typical features of the (1988) aragonite was dissolved also in shallow-water marine Czorsztyn submarine swell (Fig. 1, PI. I-A). Part of them environments, during the Jurassic. could be dated by microfauna (e.g. Tintinnids) and, occa­ sionally, also by Oxfordian brachiopods. A large strati- graphical range of synsedimentary faults, visualized as nep­ tunic dykes, is delineated in Tab. 1. Repeated opening of 2.5. Hardgrounds fractures was proved at Vrsatec by double filling: Callovian- Oxfordian + Tithonian, Callovian-Oxfordian + Albian (MISI'K, Hardgrounds of several types (Fig. 1) accompanying 1979). The filling of neptunic dykes and voids is mostly of red short submarine hiatuses may be caused by changes of the colour. It contains a special association of foraminifers such current regime. The ferro-manganese crust, a few centi­ as small Trocholina, Turrispirillina, Patellina, abundant "micrometer- s thick, from the locality Babina contained 14,3% foraminifers" (chitinous membranes of juvenile foraminifers, Mn02 and 15,3 % Fe2 03. The black manganese crust from so-called Scytinascias). Nesting organisms and coelobites Mikusovce consists of 50,5 %Mn02 and 1,6 %Fe203. Both such as special