Wyniki wyszukiwania - BazTech

1

Timing of Langhian bioevents in the Carpathian Foredeep and northern Pannonian Basin in relation to oceanographic, tectonic and climatic processes

Holcová K., Doláková N., Nehyba S., Vacek F.

Geological Quarterly

|

2018

|

Vol. 62, No. 1

3--17

EN

The succession of bioevents in planktonic foraminifer and calcareous nannoplankton communities is reviewed and summarized for the Carpathian Foredeep and northern Pannonian Basin in the time interval between ~16 and 13.5 Ma. This succession can be subdivided into three principal intervals: (1) an interval with rare Praeorbulina sicana and P. glomerosa. It was characterized by a limited immigration of index taxa linked to the lack of a warm surface water layer in the Central Paratethys. This interval can be correlated with the first Badenian transgression near the Burdigalian/Langhian boundary. The rare occurrence of biostratigraphical markers does not allow its precise dating and interregional correlation; (2) a brief interval of the first occurrences of Praeorbulina circularis, Orbulina suturalis and Helicosphaera waltrans. This can be related to the formation of a warm surface water layer suitable for the survival of orbulinas and praeorbulinas and a change from estuarine to anti-estuarine circulation. This interval can be correlated with the second Badenian transgression, which, however, was not isochronous over the area as inferred from different successions of these first occurrences; (3) a limited appearance of new index taxa in the Central Paratethys prior to the Wielician Salinity Crisis. This time interval was characterized by increased seasonality and salinity oscillations followed by climate cooling. A “reverse” migration of the stress-tolerant species Helicosphaera walbersdorfensis from the Central Paratethys to the Mediterranean is suggested. Several local bioevents with limited stratigraphic correlation potential have been recognized in this interval.

2

The Early Miocene residual flysch basin at the front of the Central Western Carpathians and its palaeogeographic implications (Magura Nappe, Poland)

Oszczypko-Clowes M., Oszczypko N., Piecuch A., Soták J., Boratyn J.

Geological Quarterly

|

2018

|

Vol. 62, No. 3

597--619

EN

In the Polish sector of the Magura Nappe, along the front of the Pieniny Klippen Belt, strongly tectonized calcareous flysch up to 1000 m thick is exposed. Previously these deposits, composed of thin- to thick-bedded flysch, with a packet of Łącko-type marls, have been included into several Paleocene/Eocene formations, e.g., the Szczawnica Formation. This formation contains a poor assemblage of agglutinated foraminifera and a relatively rich assemblage of calcareous nannoplankton, with abundant reworked species. The youngest species give evidence of the NN2 Zone (Lower Miocene). Additionally, in three profiles (Szlachtowa, Knurów and Waksmund) of the Kremna Fm., Early Miocene foraminifera have been recognized. This research documented that during the Burdigalian, at the front of Central Western Carpathians, there still existed a residual marine basin probably up to 100 km wide. These deposits also contain thick packages of exotic carbonate conglomerates derived from the SE, previously regarded as the Jarmuta Formation.

3

Calcareous nannoplankton in the Upper Jurassic marine deposits of the Bohemian Massif: new data concerning the Boreal–Tethyan communication corridor

Holcová K., Holcová M.

Geological Quarterly

|

2016

|

Vol. 60, No. 3

624--636

EN

Calcareous nannoplankton assemblages from the Jurassic relict deposits in the northern part of the Bohemian Massif are described here for the first time. They are generally of low diversity and dominated by watznaueriaceans. Some of them are diagenetically affected, probably due to dolomitisation. Calcareous nannoplankton enables the stratigraphical range of the Northern Bohemia Jurassic succession to be extended to the Tithonian by reference to the stratigraphical range of Jurassic platform sequences in Central Poland and the eastern part of the Bohemian Massif. The Oxfordian–Kimmeridgian nannofossil assemblages indicate a generally oligotrophic condition of the restricted sea with episodic fluvial input containing terrestrial nutrients. The character of the upper part of the water column was generally uniform and did not reflect variability at the sea-floor expressed by lithofacies diversity. The palaeoenvironment interpreted for the famous former palaeontological locality “Sternberk Quarry” was characterized by a higher nutrient content and more stable environment. The Tithonian nannofossil assemblages contain warm-water Tethyan taxa which suggest south-north migration of nannoplankton due to warming during the Jurassic–Cretaceous boundary interval.

4

Quantitative studies of the calcareous nannoplankton of Sarmatian deposits : case studies in the Sieniawa–Rudka area (Outer Carpathian Foredeep, Poland)

Lelek D., Oszczypko-Clowes M., Oszczypko N.

Annales Societatis Geologorum Poloniae

|

2016

|

Vol. 86, No. 1

29--57

EN

The aim of this study was the qualitative and quantitative analysis of the calcareous nannofossil assemblages of the Machów Formation, belonging to the supra-evaporitic complex of the Polish Carpathian Foredeep Basin (PCFB). The work was concentrated in the eastern part of the PCFB, in the Sieniawa–Rudka area (Ryszkowa Wola Horst). Samples were collected from the Rudka-13 and Wylewa-1 boreholes. On the basis of calcareous nannoplankton, these deposits were assigned to the upper part of the NN6 Zone combined with the NN7 Zone, which corresponds to the Sarmatian s.s. of the Central Paratethys (upper Serravallian of the Mediterranean scale). Conclusive determination of the biozone NN7 was problematic, owing to the absence of the rare zonal marker species Discoaster kugleri. The typical association of the undivided NN6–NN7 Zone was of low species diversity and usually dominated by Coccolithus pelagicus, Cyclicargolithus floridanus and Reticulofenestra pseudoumbilica (> 7 µm). On the basis of the relative abundance of species, a significant amount of redeposition was deduced. The reworked nannofossils were mostly Eocene in age. The Oligocene, Early Miocene and Late Cretaceous species occurred much less frequently. The dominance of Eocene forms indicates the Carpathians as the main supply area. The Late Cretaceous taxa may have originated from the Senonian marly deposits of the Miechów Trough in the north. Statistical treatment of the quantitative data was performed using multivariate cluster analysis and Nonmetrical Multidimensional Scaling (nMDS). The composition of the calcareous nannofossil assemblages, together with the high percentage of allochthonous taxa, indicate a shallow, coastal environment with a high supply of nutrients.

5

Reconstruction of the unusual Middle Miocene (Badenian) palaeoenvironment of the Carpathian Foredeep (Lomnice/Tišnov denudational relict, Czech Republic)

Holcova K., Brzobohatý R., Kopeckáa J., Nehyba S.

Geological Quarterly

|

2015

|

Vol. 59, No. 4

654--678

EN

Multiproxy sedimentological, gamma-spectrometric, foraminiferal, calcareous nannoplankton, and otolith data were used for the reconstruction of the Badenian (Middle Miocene) history of the Moravian part of the Carpathian Foredeep. The study material originated from the new borehole LOM-1, which drilled >20 metres of monotonous clayey siltstones with exceptionally rich and well-preserved microfossil assemblages. Distal parts of the Carpathian Foredeep (a forebulge depozone) are exposed in this succession. Generally, a quiet environment of outer shelf to upper bathyal of monotonous clayey silts was interpreted, which is typical for the proximal parts of a peripheral foreland basin. The section studied can be subdivided into six intervals, confirming the cyclical character of Middle Miocene sedimentation in the Central Paratethys. Interannual oscillations of nutrient content, temperature and/or salinity are interpreted based on the oscillations of geochemical as well as palaeobiological data. The turnover connected with the initiation of the Middle Miocene Climatic Transition is recorded above the LO (last occurrence) of Helicosphaera waltrans in agreement with previous observations in the Carpathian Foredeep. The changes include cooling, a decrease in nutrients, a probable increase of the salinity of surface water, and increase of seasonality. Seasonality was manifested by an alternation of mixed and stratified water columns with a seasonal input of nutrients. Concerning nutrients, sources of seasonal riverine input or seasonal upwelling are both possible.

6

Fossils from the Silesian-Subsilesian series of the Polish Western Carpathians : the implications for changes in sea-level and the marine environment during the Albian-Turonian

Szydło A., Jugowiec-Nazarkiewicz M., Olszewska M.

Geological Quarterly

|

2015

|

Vol. 59, No. 1

215--228

EN

Fossils and exotics from the Albian-Cenomanian deposits of the Western Polish Carpathians are discussed in relation with changes in depositional environments. Environmental conditions were controlled by geotectonic activity, sea-level changes and also anoxic and biotic events. During the Albian-the Early Cenomanian, and in the Turonian the fall in sea level led to increased supply of coarse-grained material rich in siliceous and sometimes calcareous bioclasts and exotics. This cyclic process has contributed to changes in the marine biota. In the Albian monogenic foraminiferal assemblages with the surficial epifauna corresponding to the organic influx and oxygen deficiency (OAE 1b) were evolved into more variable associations including deep infauna, which indicated more aerobic conditions. Under these conditions also preserved planktonic and calcareous benthic fossils, which indicated the supply of terrigenous material from shallow-water environments and land. During the Albian-Turonian transition intensive subsidence and volcanic activity associated with eustatic sea-level rise led to intensive production of phytoplankton. The sea-surface productivity and enhanced upwelling resulted in expanded short-term oxygen minima at the end of the Albian (OAE 1d) and the Cenomanian (OAE 2). In the latter interval benthic forms almost extinct while siliceous and calcareous plankton survived. In the Turonian changes in sea-level and sedimentary regime led to recolonization of the basin bottom.

7

Calcareous nannofossils and foraminifera from the youngest deposits of the Siary Subunit (Oligocene, Magura Nappe, Polish Outer Carpathians)

Garecka M., Szydło A.

Annales Societatis Geologorum Poloniae

|

2015

|

Vol. 85, No. 1

205--219

EN

The calcareous nannoplankton and foraminifera from the Gładyszów Beds, regarded as the youngest deposits in the northern marginal Siary Subunit of the Magura Nappe in Poland, are characterized. The material investigated comes from outcrops in the vicinity of Gładyszów and from the Gładyszów PIG-1 borehole. The analysis allowed the establishment of the age of these deposits as not older than late Rupelian–early Chattian (the calcareous nannoplankton NP24 Zone). The taxonomic affiliations, environmental associations and preservation of the microfossils were analyzed to document the sedimentary processes and environmental conditions during the geotectonic transformation of the Magura Basin in the Oligocene. These microfossils also were compared with those reported from the terminal deposits of the Outer Carpathians and the Podhale Basin.

8

Paleogene microfossils from the submarine debris flows in the Skole basin (Polish and Ukraine Outer Carpathians)

Szydło A., Garecka M., Jankowski L., Malata T.

Geology, Geophysics and Environment

|

2014

|

Vol. 40, no. 1

49--65

EN

Biostratigraphic analysis of fossils material has allowed the documentation of sediment gravity flows in the Skole basin during the Paleocene and Eocene times, and also in the Eocene-Oligocene transition. This most external basin of the NE Outer Carpathians was a marginal sea especially sensitive to geotectonic instability and relative sea-level change, favoring the development of down slope movements at these times. The dominance of calcareous forms in foraminifera, and a large share of redeposited species among the nanno- and microfossils indicate a close relationship of sediments containing them with the shelf environment and documents not too long transport. Additionally the recycled forms are often well preserved, indicating that the rock contained in flows were only plasticized and hydrated while the material itself was not a subject of significant mechanical processing in contrast to that one, which directly documented down slope moving. The latter forms are bad preserved and their fossil remains are usually corroded, partially dissolved and broken during this process. In addition, the planktonic forms including foraminifera, calcareous dinocysts and nannoplankton allow documenting the time of the final deposition of the sediment transported on slope.

9

Biostratygrafia utworów miocenu środkowego w otworze badawczym Trojanowice 2 na podstawie nanoplanktonu wapiennego

Garecka M.

Biuletyn Państwowego Instytutu Geologicznego

|

2014

|

nr 459

33--43

PL

Celem opracowania jest rozpoziomowanie utworów miocenu środkowego w profilu Trojanowice 2 na podstawie zespołów nanoplanktonu wapiennego. W zespołach nanoplanktonu dominują gatunki długowieczne należące do Coccolithaceae i Prinsiaceae. Mniej licznie występują: Helicosphaeraceae, Sphenolithaceae i Discoasteraceae. Na podstawie oznaczonych w próbkach gatunków: Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula oraz niewielkich rozmiarów form należących do rodzajów Reticulofenestra i Helicosphaera badane utwory odniesiono do poziomów kokolitowych NN5 i NN6 w standardowej zonacji Martiniego.

EN

The aim of the study was to establish the zonation of Middle Miocene sediments in the Trojanowice 2 borehole, based on calcareous nannoplankton investigations. Long-ranging families are dominant, representing Coccolithaceae (Coccolithus pelagicus) and Prinsiaceae (small reticulofenestrids, R. pseudoumbilica). Helicosphaeraceae (small helicosphaerids, H. kamptneri), Sphenolithaceae and Discoasteraceae, which are important for stratigraphic conclusions, occur less frequently. Based on the co-occurrence of Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula and small forms belonging to the Reticulofenestra and Helicosphaera species, the sediments are included into NN5 and NN6 calcareous nannoplankton zones sensu Martini.

10

Record of changes in the Oligocene–Miocene sediments of the Menilite–Krosno series of the Skole Unit based on calcareous nannoplankton studies – biostratigraphy and palaeogeographical implications (Polish Outer Carpathians)

Garecka M.

Biuletyn Państwowego Instytutu Geologicznego

|

2012

|

nr 453

1--21

EN

The biostratigraphic investigation included the Menilite–Krosno Series of the Skole Unit overlying the Globigerina Marls. Seven calcareous nannoplankton zones (sensu Martini, 1971) were distinguished in these sediments: NP23, NP24, NP25, NN1, NN2, NN3? and NN4. Based on the species diversity of the assemblage, their abundances and preservation, as well as palaeoenvironmental and palaeoclimatic conditions that controlled the basin during deposition of the Menilite and Krosno Beds have been identified. The Skole region was located at the periphery of the Paratethys basin during Late Oligocene–Early Miocene times. Based on the calcareous nannoplankton assemblage, the phase of isolation of the Paratethys (NP23) from the Mediterranean was documented. The restoration of normal marine conditions (NP24–NP25), sea-level fluctuations (sea-level fall?) at the Oligocene–Miocene boundary (uppermost part of the NP25–NN1), a phase of relative sea-level rise (NN2, NN3?, NN4) and the end of flysch sedimentation in the Skole Unit in the NN4 Calcareous Nannoplankton Zone were also identified.

PL

Badaniami biostratygraficznymi objęto utwory serii menilitowo-krośnieńskiej jednostki skolskiej położone w profilu powyżej poziomu margli globigerynowych. W obrębie utworów tej serii wyróżniono siedem poziomów nanoplanktonowych sensu Martini (1971): NP23, NP24, NP25, NN1, NN2, NN3? i NN4. Na podstawie składu zespołu nanoplanktonu wapiennego, jego zróżnicowania gatunkowego, liczebności i stanu zachowania podjęto próbę określenia warunków paleośrodowiskowych i paleoklimatycznych w czasie osadzania warstw menilitowych i krośnieńskich jednostki skolskiej. Są one ściśle związane z warunkami, jakie panowały w późnym oligocenie–wczesnym miocenie w basenach Paratetydy i z położeniem rejonu skolskiego na peryferiach tego basenu. Udokumentowano etap odizolowania basenu Paratetydy (NP23) od innych jego rejonów, etap warunków normalno-morskich, a więc odzyskania połączeń z otwartym morzem (NP24–NP25), wahania poziomu morza na pograniczu późnego oligocenu i wczesnego miocenu (najwyższa część NP25–NN1), etap względnego podniesienia poziomu morza, transgresji (NN2, NN3?, NN4) i końca sedymentacji fliszowej w basenie skolskim w poziomie NN4.

11

Correlation of the Middle Miocene deposits in SE Poland and western Ukraine based on foraminifera and calcareous nannoplankton

Garecka M., Olszewska B.

Annales Societatis Geologorum Poloniae

|

2011

|

Vol. 81, No 3

309-330

EN

The aim of this study is to compare the assemblages of foraminifera and calcareous nannoplankton from the Middle Miocene sediments from SE Poland and western Ukraine. Detailed investigations revealed a high degree of similarity of foraminiferal assemblages of the Pecten/Spirialis beds of Poland and the Kosiv Formation of Ukraine. Assemblages from both areas are characterized by numerous arenaceous species of foraminifera (Hyperammina granulosa, Ammodiscus miocenicus, Haplophragmoides indentatus, H. laminatus), radiolarians, pteropods and index planktic species Velapertina indigena. High degrees of similarity also display assemblages from the Krakowiec beds (Poland) and the Dashava Formation (Ukraine). The lower parts of both subdivisions are characterized by the presence of Anomalinoides dividens. Saccammina sarmatica, Bolivina sarmatica, Brizalina nisporenica, and Porosononion granosum occur in the upper parts. Chloropycean Halicoryne morelleti is a characteristic element of the assemblages. The calcareous nannoplankton assemblages contain almost identical species. The deposits lying above the evaporites (which belong to the NN6 zone) are included into the NN6, undivided NN6-NN7, and NN7 zones. The gradual impoverishment of the species of the upper part of NN6 and the lower part of NN7 zones is observed. The assemblages of the Krakowiec beds and the upper part of the Kosiv and Dashava formations are of low species diversity and are mainly restricted to a few species with high abundance. The assemblage is composed of placoliths (Coccolithus and Reticulofenestra species), high number of the reworked nannofossils and damaged elements.

12

The Paleogene and early Neogene stratigraphy of the Beskid Sądecki Range and Lubovnianska Vrchovina (Magura Nappe, Western Outer Carpathians)

Oszczypko N., Oszczypko-Clowes M.

Acta Geologica Polonica

|

2010

|

Vol. 60, no. 3

317-348

EN

The lithostratigraphy and biostratigraphy of the Bystrica/Tylicz and Krynica facies zones of the Magura Nappe have been studied in the Beskid Sadecki Range and Lubovnianska Vrchovina (Polish and Slovak parts of the Western Outer Carpathians respectively). The new, Tylicz Zone is established, and the Szczawnica, Zarzecze, Magura and Kremna formations are redefined and described. These formations, spanning over 35 myrs, represent a synorogenic deep-water turbidites depositional system that dominated the southern part of the Magura Basin after the collision of the Alcapa Mega Unit with the Czorsztyn/Oravic ridge. The calcareous nannoplankton zones NP14-NP25 (Middle Eocene to Late Oligocene) and NN1-NN2 (Early Miocene) were recognized.

13

New data on the late Badenian–Sarmatian deposits of the Nowy Sacz Basin (Magura Nappe, Polish Outer Carpathians) and their palaeogeographical implications

Oszczypko-Clowes M., Oszczypko N., Wójcik A.

Geological Quarterly

|

2009

|

Vol. 53, No 3

273-292

EN

In the Nowy Sacz Basin, newly exposed Middle Miocene deposits have been studied and sampled in the Kamienica Nawojowska, Poprad and Dunajec rivers. The calareous nannoplankton of the freshwater to marine deposits was examined. Palegrey and brown clayey shales with plant remains and thin seams of lignite represent the freshwater depos its of the Biegonice Formation. These deposits pass upwards into ca. 50 m thick packet of brackish and marine deposits, represented mainly by dark marly shales with bivalves and gastropods of the Iwkowa and Niskowa formations. These deposits contain relatively rich late Badenian to Sarmatian calcareous nannoplakton (NN6/7 Zone).

14

Zintegrowana biostratygrafia węglanowych osadów warstw cieszyńskich w polskich Karpatach Zachodnich

Olszewska B., Szydło A., Jugowiec-Nazarkiewicz M., Nescieruk P.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

|

2008

|

T. 34, z. 3/1

33-59

PL

W pracy przedstawiono charakterystykę stratygraficzną dolnych łupków i wapieni cieszyńskich w oparciu o zróżnicowane spektrum mikroskamieniałości. Rozmieszczenie i migracja tych mikroorganizmów do basenu cieszyńskiego, usytuowanego na południowej krawędzi Platformy Zachodnioeuropejskiej, były określone jego geotektoniczną transformacją. Pozycję niefliszowych, węglanowych utworów basenu (dolne łupki cieszyńskie i dolna część wapieni cieszyńskich) określają zespoły tytońskich mikroskamieniałości z pojedynczymi elementami późnego kimerydu. Natomiast sedymentacja węglanowych turbiditów (wyższa część wapieni cieszyńskich) miała miejsce głównie w okresie berias - walanżyn z prawdopodobną kontynuacją do (?późnego) hoterywu.

EN

Microfossils from the Tithonian-(?Late) Hauterivian carbonate deposits of the Cieszyn Beds (Lower Cieszyn Shales and Cieszyn Limestones) are reviewed. The distribution and migration of microorganisms into the Carpathian (Cieszyn) Basin were determined by geotectonic transformation of the Cieszyn Basin situated on the southern margin of the Western European Platform. The age of the nonflysch carbonate deposition in the Cieszyn basin (Lower Cieszyn Shales, and lower part of the Cieszyn Limestones) is documented by Tithonian calcareous microfossils accompanied by Late Kimmeridgian elements whereas the development of carbonate turbidite deposition in the Beriassian - Valanginian time (Cieszyn Limestones), probably continued up to the (?Late) Hauterivian.

15

Granica oligocen/miocen w polskich Karpatach zewnętrznych na podstawie nanoplanktonu wapiennego

Garecka M.

Biuletyn Państwowego Instytutu Geologicznego

|

2008

|

nr 432

1-53

PL

Badaniami objęto utwory serii menilitowo-krośnieńskiej jednostek śląskiej i skolskiej wschodniej części polskich Karpat Zewnętrznych powyżej korelacyjnych poziomów wapienia jasielskiego i/lub wapienia z Zagórza. W jednostce śląskiej granica oligocen/miocen przebiega w wyższej części warstw krośnieńskich dolnych, w południowej części jednostki - w otryckim regionie facjalnym, w wyższej części łupkowo-piaskowcowej serii nadotryckiej warstw krośnieńskich dolnych, natomiast w południowej części leskiego regionu facjalnego jednostki śląskiej - w obrębie serii przeławicających się pakietów gruboławicowych piaskowców i drobnorytmicznych osadów turbidytowych warstw krośnieńskich dolnych. W bardziej północnej części jednostki seria ta jest zastępowana przez kompleks gruboławicowych piaskowców facji leskiej i w wyższej części tego wydzielenia stwierdzono obecność gatunków mioceńskich. W jednostce skolskiej, w jej południowej części, granica przebiega w niższej części warstw krośnieńskich dolnych, a w bardziej północnej i zachodniej części tej jednostki - w obrębie warstw menilitowych. Jako gatunki wskaźnikowe dla wyznaczenia granicy oligocen/miocen zaproponowano: Helicosphaera mediterranea Muller, Helicosphaera recta Haq, Helicosphaera scissura Miller, Dictyococcites bisectus (Hay, Mohler et Wade) Bukry et Percival, Zygrhablithus bijugatus Deflandre i Sphenolithus delphix (Bukry).

EN

The aim of this work was to establish the Oligocene/Miocene boundary in the eastern part of the Polish Outer Carpathians on the basis of calcareous nannoplankton analysis. The investigations focused on the Menilite-Krosno Series of the Silesian and Skole Units overlying the Jasło and/or Zagórz limestone chronohorizons. In the Silesian Unit, the Oligocene/ Miocene boundary is placed in the upper part of the Lower Krosno Beds. In the Otryt facial region (southern part of the Silesian Unit), this boundary runs within the upper part of the shaly-sandy Supra-Otryt series of the Lower Krosno Beds. In the southern part of the Lesko facial region, the boundary is established within a series of thick-bedded sandstones and fine-rythmical turbidite deposits of the Lower Krosno Beds. In the northern part of this region, the series is replaced by thick-bedded sandstones of the Lesko facies. Miocene taxa were recorded in the upper part of these deposits. In the southern part of the Skole Unit the Oligocene/Miocene boundary runs within the lower part of the Lower Krosno Beds, whereas in the more northern and western parts of the unit - within the Menilite Beds. Among taxa proposed as indicative for the Oligocene/Miocene boundary, Helicosphaera mediterranea Muller, Helicosphaera recta Haq, Helicosphaera scissura Miller, Dictyococcites bisectus (Hay, Mohler et Wade) Bukry et Percival, Zygrhablithus bijugatus Deflandre, Sphenolżthus delphix (Bukry) were recorded.

16

New data on the stratigraphy of the folded Miocene Zone at the front of the Ukrainian Outer Carpathians

Andreyeva-Grigorovich A., Oszczypko N., Ślączka A., Oszczypko-Clowes M., Savitskaya N., Trofimovicz N.

Acta Geologica Polonica

|

2008

|

Vol. 58, no. 3

325-353

EN

The litho- and biostratigraphy (calcareous nannofossils and foraminifera) were studied in several sections of the folded Miocene Zone (Boryslav-Pokuttya and Sambir nappes) of the Ukrainian Outer Carpathians. Based on new biostratigraphic data, the age and correlation of the folded Miocene deposits in the marginal part of the Ukrainian and Polish Outer Carpathians were established. The deposits studied range from the Early Miocene (Early Burdigalian NN2 Zone) to the early Late Miocene (NN9 Zone). The facies and similarity in ages of the youngest deposits of the folded Middle Miocene strata in Poland [Stebnik (Sambir) Nappe and Zgłobice thrust-sheets] and in Ukraine (Sambir Nappe) implies that they were folded at same time and that they represent a similar system of tectonic units, developed in front of the advancing Carpathian orogen.

17

Nanoplankton wapienny górnokredowych facji pelagicznych jednostki podśląskiej polskich Karpat fliszowych

Jugowiec-Nazarkiewicz M.

Biuletyn Państwowego Instytutu Geologicznego

|

2007

|

nr 426

53-70

PL

W pelagicznych osadach jednostki podśląskiej (marglach węglowieckich, marglach typu frydeckiego, marglach żegocińskich, piaskowcach z Rybia) oraz w marglach bakulitowych jednostki skolskiej i marglach z Bonarki występujących na monoklinie śląsko-krakowskiej (odsłonięcie Bonarka w Krakowie) stwierdzono liczne formy nanoplanktonu wapiennego wieku kampan-mastrycht. Wyznaczono poziomy nanoplanktonowe, określając wiek badanych osadów. W marglach bakulitowych, nazywanych też marglami z Węgierki, występujących w jednostce skolskiej, odnotowano podobny skład i charakter nanoplanktonu wapiennego jak w szarych marglach typu frydeckiego występujących w jednostce podśląskiej w zachodniej części Karpat. W badanych osadach jednostki podśląskiej nie stwierdzono ciągłego przejścia sedymentacyjnego między osadami mastrychtu i danu. Badania nanoplanktonu potwierdziły istnienie połączenia między strefą borealną i tetydzką na obszarze polskich Karpat zewnętrznych w kampanie i mastrychcie, o czym świadczy obecność w próbkach form nanoplanktonu uważanych za typowo borealne.

EN

In pelagic sediments of the Subsilesian Unit (Węglówka marls, Frydek-type marls, Żegocina marls and Rybie sandstones) and in the bakulit marls from the Skole Unit, and in marls from Bonarka in Silesian-Cracow Monocline many forms of calcareous nannoplankton of Campanian-Maastrichtian age were noted. Distinguishing of several nannoplankton assemblage zones allowed for more detailed time resolution of the studied sediments. Existing of the connection between the boreal and Tethyan realms in Polish Outher Carpathians during Campanian/Maastrichtian has been confirmed. Calcareous nannoplankton of the bakulit marls (Skole Unit) appeared similar to that from the Frydek-type marls (Subsilesian Unit). No continuous transition between sediments of the Maastrichtian and Danian within the studied Subsilesian Unit has been stated. Transition between Boreal and Tethyan realms on the Polish Outher Carpathians area, during Campanian and Maastrichtian age are confirmed.

18

Micropalaeontologic, geochemical and cyclostratigraphic approach for the timing of the Early Toarcian Oceanic Anoxic Event in the Paris Basin (GPF-Sancerre borehole)

Clemence M., Huret E., Bartolini A., Galbrun B., Gardin S., Hinnov L., Beaumont V.

Volumina Jurassica

|

2006

|

Vol. 4, no. 1

154-155

EN

The marine sedimentary record of the Toarcian exhibits evidence for a perturbation of the global carbon cycle associated with high burial of organic matter, known as the Early Toarcian Oceanic Anoxic Event (OAE). It is accompanied by climate warming, elevated rates of marine faunal extinction and short-lived, strong negative isotope excursion in both oceanic and terrestrial reservoirs. The timing and the pattern of the negative shift in 13C are critical for understanding the possible mechanism of this isotopic event, and the nature and the origin of the Early Toarcian OAE. To improve our understanding of the palaeoenvironmental background of the Early Toarcian OAE, we have investigated the sedimentary record of the GPF-Sancerre borehole from the southern Paris Basin (Cher, France) by integrating geochemical analyses (13Corg, TOC and CaCO3) with synecological analyses of benthic foraminifers and calcareous nannofossils; and assessing the duration of the 13C excursion by cyclostratigraphic analysis using magnetic susceptibility (MS) and CaCO3 data. Our results indicate progressive environmental deterioration from Domerian/Toarcian to a paroxysm coincident with the Early Toarcian OAE (highest TOC values and negative excursion of 13Corg). This deterioration is marked by a high fertility period that precedes anoxic conditions. The OAE coincides with a major crisis in the benthos and with a decrease of calcareous nannofossils. Following this major dysoxic episode, the water column is characterized by a succession of alternating suboxic and stagnation phases that correlates well with positive values of 13Corg. These results attest of a highly perturbed environment, characterized by the presence of opportunist species both in the benthos and nannoplankton communities. To quantify the timing of these events, high resolution cyclostratigraphic analysis is applied to MS and CaCO3 data (sampling interval – 2 cm). Cycles of ca. 0.5, 1 and 2.5 m are observed. The calculation of cycle frequency ratios matches that of the Milankovitch orbital cycles. The duration of the negative isotope excursion can be estimated by counting cycles to 120,000š40,000 yrs. The diminution of cycle thicknesses at the Domerian/Toarcian boundary (353-358 m interval) reflects a decrease of sedimentation rate. We interpreted this result as an evidence for a potentially condensed level. This multi proxies approach is innovative and promising to better understand the water column dynamic during the OAE (nannofossil and foraminifer association), shows that the OAE is a multiphase event (beginnings, acme and recovery) and estimates brief events (<200,000 yrs), follows the sedimentation rate evolution and highlights potential hiatuses (condensed zones).

19

Cyclostratigraphy and chronology of the Domerian in the Paris Basin (GPF-Sancerre borehole, Cher, France)

Huret E., Galbrun B., Clemence M-E., Gardin S., Collin P-Y., Rouget I., Boulila S., Trouillefou P.

Volumina Jurassica

|

2006

|

Vol. 4, no. 1

172-173

EN

Marine sedimentary successions recording Milankovitch orbital forcing of paleoclimate variations allowed the orbital tuning of Neogene Time scale (Lourens et al. 2004). For Mesozoic times the most recently calculated astronomical solution is not reliable (Laskar et al. 2004) and the only possibility is to provide “floating chronologies” to estimate the durations of geological processes. Detection of orbitally forced cyclicity patterns from Mesozoic sedimentary sections needs analysis of the right palaeoclimatic proxy which has to be easy in use. Most often in marine sediments magnetic susceptibility (MS), which integrates the concentration of magnetic grains, reflect changes in detrital influx and then it can be used as a palaeoclimatic proxy (Mayer & Appel 1999). Thus MS variations analysis of thick Mesozoic sedimentary successions is probably the easiest paleoclimatic proxy to use, fast and allowing high stratigraphic resolution that would be difficult to obtain with conventional methods. Such methodology was already successfully used for analysis of Jurassic successions (Weedon et al. 1999). We report a cyclostratigraphic analysis of MS record from the Domerian (Upper Pliensbachian, Lower Jurassic) recovered in the GPF-Sancerre borehole (southern Paris Basin, France). The Domerian formation is composed of marly-limestones and marls, and is 50 meters thick. The recovery is almost 100%. The Spinatum and Margaritatus ammonite zones are well recognized, as well as nannofossils and benthic foraminifers datums. High resolution (2 cm spacing) MS measurements were realized with a Bartington MS2-E1 sensor. MS variations are in accordance with lithology: very weak values in marly-limestones, higher values when the clays percentage increase. Long term evolution of MS allow to establish a sequential interpretation. The high frequency variations of MS were the subject of a cyclostratigraphic study by spectral analysis and the realization of amplitude spectrum. Cycles of 0.4, 1, 2 and 6.5 m thick were recognized. Using the methodology of frequency ratios, these cycles are interpreted to record orbital precession, obliquity and eccentricity (100 and 400 ky), respectively. Thus, the duration of the Domerian and the different ammonite zones can be estimated. Moreover, the realization of amplitude spectrum allows to estimate the sedimentation rate evolution and to interpret the cycle evolution breaks as hiatuses. As a matter of facts we observed in the Upper Domerian a significant decrease of cycle’s thickness that we interpreted as a drop of sedimentation rate and probably as a condensed level (Clemence et al. this volume).

20

The Pliocene-Pleistocene boundary in pelagic oozes off Reunion Island, western Indian Ocean

Duczmal-Czerniewicz A., Jugowiec-Nazarkiewicz M., Szydło A.

Acta Geologica Polonica

|

2006

|

Vol. 56, no. 4

407-419

EN

Nannoplankton and foraminifera from the pelagic oozes from a water depth of 3 684 meters, 150 km southeast of Reunion Island, Indian Ocean, prove the NN18 and NN19 nannoplankton zones, indicating the Pliocene.Pleistocene boundary. The Pliocene.Pleistocene boundary was established at 220.230 cm depth. The abundance of Globorotalia truncatulinoides increases from about 50 cm below the sea floor. The microfossil assemblages and clay mineral components of the sediments may be correlated with changes of climatic conditions influenced by glaciations.