INDICATIONS OF THE MIDDLE JURASSIC EMERGENCE IN THE CZORSZTYN UNIT (PIENINY KLIPPEN BELT, WESTERN CARPATHIANS)
Abstract: A breccia of rounded crinoidal limestone clasts cemented by two generations of stromatolites, then by radiaxial cement with remaining voids filled by marine sediments i.e. crinoidal detritus, micrite with bivalve shells or micrite with Pokornyopsis ostracods was found at Horne Sŕnie quarries near Trencin. This breccia, which can be assigned to the Krasin Breccia Member (Middle to Upper Jurassic of Czorsztyn Unit), bears several signs of freshwater influence. Isotopic data from the first stromatolite generation display a negative δ13C, the clasts in the breccia are rounded and some dissolutional effects have been observed in the voids. The final filling of the cavities with crinoidal detritus and later with filament microfacies suggests that the breccia was formed in the time of the transition between Bathonian and Callovian. It is the first evidence of freshwater diagenesis in the Pieniny Klippen Belt.
CHLORITE AND CHLORITE-HEMATITE ONCOIDS FROM THE JURASSIC LIMESTONES OF THE WESTERN CARPATHIANS, SLOVAKIA
Abstract: Pelagic chlorite and chlorite-hematite oncoids occur in red nodular limestones of the Toarcian and Oxfordian age, thought to represent intervals of condensed sedimentation. At a single locality, they were also found in an intraformational limestone breccia with fragments of a calcrete. Intraclasts, fragments of hardgrounds and belemnite rostra form oncoid nuclei. Wrinkled laminae and pseudocolumnar structures characterize their cortices. Encrusting foraminifers are important builders of the studied oncoids. Rare synsedimentary cracking of oncoids is indicated by the presence of neptunic microdykes. Sets of chlorite and hematite concentric laminae responded differently during compaction and tectonic processes. A peculiar phenomenon is the recrystallization (aggrading neomorphism) of the micrite admixture in hematite and chlorite oncoids; new-formed larger calcite grains contain the hematite pigment arranged in dendritic patterns. The hematite pigment also formed characteristic "teeth" in the early diagenetic calcite veinlets. The oncoids are formed by Fe-chlorite, polytype IIb. The origin of the chlorite was connected neither with volcanic activity nor with the initial metamorphism. The condensed sedimentation with mineralized oncoids was associated either with local conditions or with the sea level high stand.
CRETACEOUS TECTONOCHRONOLOGY OF THE CENTRAL WESTERN CARPATHIANS, SLOVAKIA
Abstract: During the Cretaceous, the Central Western Carpathians (CWC) evolved as an intracontinental thrust belt by progradational shortening from the inner (Meliatic) towards the outer (Penninic-Vahic) bounding oceanic domain. The Early Cretaceous basement nappe stacking in the internal CWC zones was coeval with distension in the external zones, followed by a collapse of the overthickened crust, unroofing of the Veporic metamorphic core complex and gravity gliding of the cover nappe systems towards the unconstrained Tatric foreland in mid-Cretaceous times. In the Late Cretaceous, shortening affected the external CWC zones and the Vahic ocean was consumed. The available data on the geochronological, magmatic, metamorphic, structural, lithostratigraphic and sedimentological record of these processes are reviewed and their broad-scale tentative interpretation is presented.
PETROLOGY OF THE WESTERN CARPATHIANS CRETACEOUS PRIMITIVE ALKALINE VOLCANICS
Abstract: In several Mesozoic tectonic units (Silesian, Tatric and Fatric ones) of the Western Carpathians, different alkaline effusive and rarely also intrusive rocks of the Cretaceous age (approx. 100 Ma) are known. Olivines, clinopyroxenes and less frequently also amphiboles form phenocrysts, and glomerophyric accumulations of them occur in places. Fine-grained devitrified matrix (up to 40 vol. %) is another constant rock component. The nature of Cpx phenocrysts documents a rapid ascent of the melt which was contaminated by the resorption (mostly of carbonates) of xenoliths. The variable composition of these rocks is mainly a result of fractional crystallization and xenolith assimilation. According to their chemical composition these rocks correspond to alkaline basalts/basanites, locally even picrites. The presence of primitive alkaline volcanics is a consequence of extending volcanic activity in their respective units.
REGIONAL STRATIGRAPHIC SCHEME OF NEOGENE FORMATIONS OF THE CENTRAL PARATETHYS IN THE UKRAINE
Authors: AIDA S. ANDREYEVA-GRIGOROVICH,
YAROSLAV O. KULCHYTSKY,
ANTONINA D. GRUZMAN,
PETRO YU. LOZYNYAK,
MARIAN I. PETRASHKEVICH,
LUDMYLA O. PORTNYAGINA,
ANTONINA V. IVANINA,
SERGEY E. SMIRNOV,
NATALIA A. TROFIMOVICH,
NATALIA A. SAVITSKAYA,
NINA J. SHVAREVA
Abstract: Detailed biostratigraphic schemes of Neogene deposits of the Transcarpathian Basin, Carpathians, Carpathian Foredeep and sedimentary cover of the South-Western margin of East-European Platform (the Central Paratethys) are compiled and supplemented by new data. The lower boundary of the Miocene of the Central Paratethys is based on planktonic microorganisms (nannoplankton, foraminifers, dinocysts). This boundary lies in the upper part of the Lower Krosno and Middle Menilite "subformations". New lithostratigraphic units are established on the basis of paleontological data: Grushiv and Zhuriv Formations, and two membered division of the Badenian stage are established. Scheme correlation with the stage scales and biostratigraphic standards (nannoplankton, foraminifers) of the Tethys, the Central and Eastern Paratethys, and also with the adjacent territories of Poland, Rumania, Slovakia, Hungary and Russia was carried out.
SPINEL-HORNBLENDE-ANTHOPHYLLITE (NEPHRITOID) NEOLITHIC AXES FROM WESTERN SLOVAKIA
Abstract: Among artifacts from several localities/sites in western Slovakia (the Male Karpaty Mts. and the Danube Upland (Podunajska pahorkatina) those composed of green Al-rich spinel, hornblende and anthophyllite are characteristic. Other minerals (olivine, clinozoisite, muscovite, ilmenite, magnetite and sphene) are present in accessory amounts. The stones bear several characteristics of nephrites. In paper we use the common term „nephritoids“ for various varieties of the discussed rocks. Primary occurrences of these Al-rich spinel-hornblende-anthophyllite rocks are not yet known. On the basis of the predominance of hornblende and anthophyllite, the rocks under consideration are thought to be products of medium-temperature metamorphism of spinel bearing orthopyroxene-clinopyroxene rocks (ferroultramafics) under static conditions and high P/H2O.
