scholarly journals The evolution of the Carpathian Foredeep Basin during the latest Badenian and Sarmatian (Middle Miocene): inferences from micropalaeontological data

2020 ◽  
Vol 64 (4) ◽  
Author(s):  
Simina Dumitriţa DUMITRIU ◽  
Zofia DUBICKA ◽  
Sergiu LOGHIN ◽  
Mihaela Carmen MELINTE-DOBRINESCU ◽  
Jolanta PARUCH-KULCZYCKA
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Foreland Basin ◽  
Taxonomic Composition ◽  
Calcareous Nannofossils ◽  
Central Paratethys ◽  
Carpathian Foredeep ◽  
The Republic ◽  
Significant Regression ◽  
Matter Flux

Seven Middle Miocene (Upper Badenian to Lower Sarmatian) sedimentary sections of the Central Paratethys, two from the Polish Carpathian Foredeep Basin (PCFB) and five from the Eastern Carpathian Foreland Basin (ECFB) of Romania and the Republic of Moldova have been analysed micropalaeontologically to better constrain the Badenian-Sarmatian Extinction Event, characterized by significant taxonomic impoverishment of both foraminifers and ostracods. Our studies show significant palaeoenvironmental changes in the basin including depth, salinity, oxygenation, and organic matter flux. The occurrence of moderately diverse planktonic foraminifera (Globigerina, Globigerinita, Globorotalia, Trilobatus, Orbulina, Velapertina) in the Upper Badenian deposits of the PCFB as well as in the ECFB and their rarity in the lowermost Sarmatian indicate an almost fully marine environment during the latest Badenian, followed by a significant regression and possible appearance of much more restricted marine conditions across the boundary. The taxonomic composition of the Sarmatian foraminifera, ostracoda and calcareous nannofossils indicate that during this interval the salinity fluctuated strongly, with the water regime varying from brackish to normal marine. In addition, the identified micropalaeontological assemblages identified show palaeoenvironmental similarity across different basins of the Central Paratethys. This supports a hypothesis of possible connections during the latest Badenian between different areas of the Central Paratethys, as well as of the existence of a gateway between the Central Paratethys and the Mediterranean realm

scholarly journals Timing of the Middle Miocene Badenian Stage of the Central Paratethys

2014 ◽  
Vol 65 (1) ◽  
pp. 55-66 ◽  
Author(s):  
Johann Hohenegger ◽  
Stjepan Ćorić ◽  
Michael Wagreich
Keyword(s):  
Sea Level ◽  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Sea Level Changes ◽  
Vienna Basin ◽  
Central Paratethys ◽  
Polarity Reversals ◽  
Global Events ◽  
Geomagnetic Polarity ◽  
Climate Transition

Abstract A new and precisely defined chronometric subdivision of the Badenian (Middle Miocene, regional stage of Central Paratethys) is proposed. This uses global events, mainly geomagnetic polarity reversals as correlated chronometric boundaries, supported by climatic and sea-level changes in addition to isotope events and biostratigraphic data. The Karpatian/ Badenian boundary lies at 16.303 Ma, at the top of Chron C5Cn.2n, which is near the base of the Praeorbulina sicana Lowest-occurrence Zone (LOZ). The Badenian/Sarmatian boundary is placed at the top of polarity Chron C5Ar.2n, thus at 12.829 Ma. In relation to three sea level cycles TB 2.3, TB 2.4 and TB 2.5 and astronomically confirmed data, the Badenian can be divided into three parts of nearly equivalent duration. The Early Badenian as newly defined here ranges from 16.303 to 15.032 Ma (top of polarity Chron C5Bn.2n). The younger boundary correlates roughly to the base of the planktonic foraminifera Orbulina suturalis LOZ at 15.10 Ma, the HO (Highest Occurrence) of the nannofossil Helicosphaera ampliaperta at 14.91 Ma (NN4/NN5 boundary) and the Lan2/Ser1 sequence boundary at 14.80 Ma. The subsequent Mid Badenian ranges from 15.032 Ma to 13.82 Ma; the latter datum correlates with the base of the Serravallian, characterized by a strong global cooling event reflected in the oxygen isotope event Mi3b. The main part of cycle TB 2.4 falls into the Mid Badenian, which can be subdivided by a short cooling event at 14.24 Ma during the Middle Miocene Climate Transition (14.70 to 13.82 Ma). The HCO (Highest common occurrence) of the nannofossil Helicosphaera waltrans at 14.357 Ma supports this division, also seen in the tropical plankton Zones M6 Orbulina suturalis LOZ and M7 Fohsella peripheroacuta LOZ that correspond roughly to the lower and upper Lagenidae zones in the Vienna Basin, respectively. The Late Badenian is delimited in time at the base to 13.82 Ma by the Langhian/Serravallian boundary and at the top by the top of polarity Chron C5Ar.2n at 12.829 Ma. The Mediterranean Langhian/Serravallian boundary can be equated with the Mid/Late Badenian boundary at 13.82 Ma. However, the Karpatian/Badenian boundary at 16.303 Ma, a significant event easily recognizable in biostratigraphy, paleoclimate evolution and sequence stratigraphy, cannot be equated with the proposed global Burdigalian/Langhian, and thus Early/Middle Miocene boundary, at 15.974 Ma

scholarly journals Stages of development in the Polish Carpathian Foredeep basin

2012 ◽  
Vol 4 (1) ◽  
Author(s):  
Nestor Oszczypko ◽  
Marta Oszczypko-Clowes
Keyword(s):  
Driving Force ◽  
Middle Miocene ◽  
Foreland Basin ◽  
Early Miocene ◽  
Accretionary Wedge ◽  
North East ◽  
Carpathian Foredeep ◽  
Outer Carpathians ◽  
The Mean ◽  
Roll Back

AbstractIn southern Poland, Miocene deposits have been recognised both in the Outer Carpathians and the Carpathian Foredeep (PCF). In the Outer Carpathians, the Early Miocene deposits represent the youngest part of the flysch sequence, while in the Polish Carpathian Foredeep they are developed on the basement platform. The inner foredeep (beneath the Carpathians) is composed of Early to Middle Miocene deposits, while the outer foredeep is filled up with the Middle Miocene (Badenian and Sarmatian) strata, up to 3,000mthick. The Early Miocene strata are mainly terrestrial in origin, whereas the Badenian and Sarmatian strata are marine. The Carpathian Foredeep developed as a peripheral foreland basin related to the moving Carpathian front. The main episodes of intensive subsidence in the PCF correspond to the period of progressive emplacement of the Western Carpathians onto the foreland plate. The important driving force of tectonic subsidence was the emplacement of the nappe load related to subduction roll-back. During that time the loading effect of the thickening of the Carpathian accretionary wedge on the foreland plate increased and was followed by progressive acceleration of total subsidence. The mean rate of the Carpathian overthrusting, and north to north-east migration of the axes of depocentres reached 12 mm/yr at that time. During the Late Badenian-Sarmatian, the rate of advance of the Carpathian accretionary wedge was lower than that of pinch-out migration and, as a result, the basin widened. The Miocene convergence of the Carpathian wedge resulted in the migration of depocentres and onlap of successively younger deposits onto the foreland plate.

scholarly journals <i>Bolboforma</i> (Phytoplankton Incertae Sedis), <i>Bachmayerella</i> and other Calciodinelloidea (Phytoplankton) from the Middle Miocene of the Alpine–Carpathian Foredeep (Central Paratethys)

2004 ◽  
Vol 23 (2) ◽  
pp. 139-152 ◽  
Author(s):  
Silvia Spezzaferri ◽  
Fred Rögl
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
High Latitudes ◽  
Calcareous Nannofossils ◽  
Geological Time ◽  
Incertae Sedis ◽  
Sedimentary Sequences ◽  
Unicellular Organisms ◽  
First Time

Abstract. Bolboforma is a microfossil of uncertain origin with affinities to protophytic algae. It generally occurs at high latitudes and/or in cool and temperate waters and has a high stratigraphic potential especially for the Miocene. Calcareous cysts of dinoflagellates represent the ‘benthic cyst stage’ of unicellular organisms belonging to the marine phytoplankton.The occurrence of Bolboforma, Bachmayerella is documented here and, for the first time, some calcareous cysts of dinoflagellates tentatively attributed to Alasphaera and Pithonella from Badenian (Langhian–Middle Miocene) sediments in Austrian and Moravian localities. Alasphaera and Pithonella were previously described from Cretaceous and Danian sediments only, therefore, their range has been extended into the Paratethyan Middle Miocene.Correlation of Bolboforma bioevents with standard geological time-scales allows confirmation, and in some cases refinement, of age assignments based on other microfossil groups, such as foraminifera and calcareous nannofossils, in Paratethyan areas. In particular, this paper presents a case study of the biostratigraphy of the Grund Formation outcropping at its type locality in Lower Austria. Age attribution of the Grund Formation has been uncertain for some time. The recovery of Praeorbulina glomerosa circularis and Uvigerina macrocarinata, associated with Bolboforma reticulata, allows the correlation of the Grund Formation with the Early Badenian (Middle Miocene). As planktonic foraminifera are generally very rare or absent in shelf deposits of many other Austrian and Moravian Middle Miocene sedimentary sequences, Bolboforma, and in particular B. reticulata, remains an important biomarker to identify lower Badenian sediments.Additionally, the new species Bolboforma gneixendorfensis Spezzaferri &amp; Rögl is described. It is generally double-chambered with a weakly reticulate wall texture and is associated with Bolboforma reticulata, B. bireticulata and/or B. moravica.

Nature and origin of carbonate particles along a transect on the western margin of Great Bahama Bank (Middle Miocene): sedimentary processes and depositional model

2008 ◽  
Vol 179 (3) ◽  
pp. 231-244 ◽  
Author(s):  
Mélanie Turpin ◽  
Laurent Emmanuel ◽  
Maurice Renard
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Calcareous Nannofossils ◽  
Western Margin ◽  
Great Bahama Bank ◽  
Permeable Sediments ◽  
Low Magnesium ◽  
Carbonate Sedimentation ◽  
Depositional Processes ◽  
Magnesium Calcite

Abstract During ODP Leg 166, Middle Miocene sediments were collected along the western margin of the Great Bahama Bank (GBB) at four sites, distributed along a proximal-distal transect. Site 1006 is located in the basin, Site 1007 at the toe-of-slope and Sites 1003 and 1005 on the mid and upper slope. The carbonate slope deposits of GBB consist of periplatform oozes, an admixture of platform-derived aragonite and high-magnesium calcite particles, and pelagic low-magnesium calcite. An assessment of carbonate sedimentation is made in order to estimate the proportion of platform-derived versus pelagic components. The originality of this study is based on the application of a separation method giving access to homogeneous granulometric fractions, ranging from 63 to 3 μm in grain diameter. This method, associated with a multidisciplinary approach (micropaleontology, optical and electronic microscopy, mineralogy – X-ray diffractometry, and trace elements geochemistry – strontium and magnesium), allows the quantification and characterization of different kinds of carbonate particles. In Miocene sediments, three types of particles display a biogenic structure: planktonic foraminifera, calcareous nannofossils and fragments of neritic organisms. Two types of particles do not exhibit any structures that allow for a determination of their origin. Based on their size and their mineralogy, we have distinguished macroparticles (calcite and dolomite) and microparticles (calcite and aragonite). The detailed study of the composition of the separated fractions highlights major differences in carbonate ooze composition between the different sites along the transect. The unlithified samples of Sites 1006 and 1007 are dominated by pelagic components (planktonic foraminifera and calcareous nannofossils) and contain aragonite microparticles. In contrast, lithified sediments of Sites 1003 and 1005 (and 1007) are characterized by higher proportions of neritic debris and particles without biologic structure, the pelagic phase is impoverished and aragonite needles are absent. The origin of particles without biological structure has been demonstrated by their spatial distribution and by mineralogical as well as geochemical criteria. The rhombohedral calcitic microparticles mainly occur at slope sites. Their high magnesium contents support a formation on the bank implying an allochthonous origin. This suggests that calcitic microparticles correspond to the bank micrite exported towards slope environments. Rhomboedral calcitic macroparticles, which fill sediment voids, originate from in situ transformations of metastable carbonates due to pore fluids, which preferentially flow in the slope permeable sediments. Two sedimentary sources are proposed: 1) an autochthonous pelagic source with low-magnesium calcitic components and 2) an allochthonous neritic source with both aragonitic and calcitic components. Export and depositional processes can be differentiated for the allochthonous particles. The neritic debris and calcitic microparticles in slope Sites 1003 and 1005 (and less frequently in Site 1007) were probably exported by gravity currents whereas the aragonite microparticles, due to their shape and granulometry, were perhaps transported as suspension and deposited at the distal Sites 1006 and 1007.

scholarly journals Late Neogene evolution of modern deep-dwelling plankton

2021 ◽  
Author(s):  
Flavia Boscolo-Galazzo ◽  
Amy Jones ◽  
Tom Dunkley Jones ◽  
Katherine A. Crichton ◽  
Bridget S. Wade ◽  
...  
Keyword(s):  
Water Column ◽  
Deep Water ◽  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Euphotic Zone ◽  
Biological Pump ◽  
Calcareous Nannofossils ◽  
The Past ◽  
Late Neogene ◽  
Global Cooling

Abstract. The fossil record of marine microplankton provides insights into the evolutionary drivers which led to the origin of modern deep-water plankton, one of the largest component of ocean biomass. We use global abundance and biogeographic data combined with depth habitat reconstructions to determine the environmental mechanisms behind speciation in two groups of pelagic microfossils over the past 15 million years. We compare our microfossil datasets with water column profiles simulated in an Earth System model. We show that deep-living planktonic foraminiferal (zooplankton) and calcareous nannofossil (mixotroph phytoplankton) species were virtually absent globally during the peak of the middle Miocene warmth. Evolution of deep-dwelling planktonic foraminifera started from subpolar-midlatitude species during late Miocene cooling, via allopatry. Deep-dwelling species subsequently spread towards lower latitudes and further diversified via depth sympatry, establishing modern communities stratified hundreds of meters down the water column. Similarly, sub-euphotic zone specialist calcareous nannofossils become a major component of tropical and sub-tropical assemblages through the latest Miocene to early Pliocene. Our model simulations suggest that increased organic matter and oxygen availability for planktonic foraminifera, and increased nutrients and light penetration for nannoplankton, favored the evolution of new deep water niches. These conditions resulted from global cooling and the associated increase in the efficiency of the biological pump over the last 15 million years.

Sign in / Sign up

Export Citation Format

Share Document