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Full-Text Articles in Physical Sciences and Mathematics

Origin, Evolutionary Classification, And Biostratigraphic Significance Of The Late Cretaceous Planktic Foraminiferal Directional Lineage Bollitruncana O.A. Korchagin, 2001, Marius Dan Georgescu May 2012

Origin, Evolutionary Classification, And Biostratigraphic Significance Of The Late Cretaceous Planktic Foraminiferal Directional Lineage Bollitruncana O.A. Korchagin, 2001, Marius Dan Georgescu

Studia UBB Geologia

Taxonomic revision of the genus Bollitruncana O.A. Korchagin, 2001 shows that it accommodates a directional lineage, which consists of two species: B. carpathica (Scheibnerová, 1963) and B. posthelvetica (Hanzliková, 1963). Bollitruncana directional lineage is restricted to Turonian. A new planktic foraminiferal biozone is recognized in the Turonian, namely the Bollitruncana carpathica Biozone.


Lower Cretaceous Limestones From The Northern Part Of Padurea Craiului (Osoiu Hill And Subpiatra Sections): Biostratigraphy And Preliminary Data On Microbial Structures, Hyam Daoud, Ioan I. Bucur, Emanoil SăSăRan, Ioan Cociuba Mar 2012

Lower Cretaceous Limestones From The Northern Part Of Padurea Craiului (Osoiu Hill And Subpiatra Sections): Biostratigraphy And Preliminary Data On Microbial Structures, Hyam Daoud, Ioan I. Bucur, Emanoil SăSăRan, Ioan Cociuba

Studia UBB Geologia

Two sections have been measured within the Lower Cretaceous deposits from the northern part of Pădurea Craiului: Osoiu Hill section and Subpiatră section. Thin sections representing more than 180 samples allowed us to present some results on the biostratigraphy, facies succession and the role of microbial structures in the genesis of these limestones. The Osoiu Hill section is dominated by fenestral limestones formed in the intertidal or in the shallow subtidal zone. Their formation is dominantly related to microbial mats. Based on foraminiferal assemblages we attribute a Lower Barremian age to these limestones. The succession in the Subpiatra section is …


The Mesozoic Carbonate Deposits From The Borehole 6042 Deleni (Transylvanian Depression), Ioan I. Bucur, Marcel-Adrian Piteiu, Emanoil SăSăRan Mar 2012

The Mesozoic Carbonate Deposits From The Borehole 6042 Deleni (Transylvanian Depression), Ioan I. Bucur, Marcel-Adrian Piteiu, Emanoil SăSăRan

Studia UBB Geologia

The borehole 6042 Deleni is among the few wells located in the central part of the Transylvanian Depression that crossed the rocks in the basement. Among these, the Mesozoic deposits were cross-cut along 916 m. Based on the investigations carried out on core samples from the Mesozoic deposits three carbonate units attributed to the Late Oxfordian -Tithonian (?Neocomian) have been separated. A preliminary evaluation of the terrigenous and carbonate-terrigenous deposits overlaying the carbonate ones indicated an Aptian-Albian, respectively Senonian age. Considerations on the paleoenvironment of the Mesozoic deposits studied are also presented.


Anomalinoides Dividens Bioevent At The Badenian/Sarmatioan Boundary – A Response To Paleogeographic And Paleoenvironmental Chnages, Sorin Filipescu Mar 2012

Anomalinoides Dividens Bioevent At The Badenian/Sarmatioan Boundary – A Response To Paleogeographic And Paleoenvironmental Chnages, Sorin Filipescu

Studia UBB Geologia

Recent investigations on the microfauna at the Badenian / Sarmatian boundary (Middle Miocene) showed interesting characters of the Anomalinoides dividens foraminifera assemblages. Several taxonomic aspects are considered in order to clarify the meaning of different stratigraphic approaches. A possible planktonic or pseudo-planktonic life of the species is suggested by micropaleontologic, paleogeographic and paleoenvironmental data.


New Remarks On The Lithology And Biostratigraphy Of The Cretaceous Deposits From Istria Depression (Black Sea Shelf), Larisa Tertiș, Ioan I. Bucur, Emanoil SăSăRan, Lucreția Ghergari Mar 2012

New Remarks On The Lithology And Biostratigraphy Of The Cretaceous Deposits From Istria Depression (Black Sea Shelf), Larisa Tertiș, Ioan I. Bucur, Emanoil SăSăRan, Lucreția Ghergari

Studia UBB Geologia

The lithological and micropaleontological study of samples collected from several boreholes drilled in the Mesozoic deposits of Istria Depression (Black See shelf) allowed the characterization of intersected Cretaceous successions. Berriasian - Valanginian deposits are terrigenous, represented mainly by sandstones in the lower parts, and clays above. It is impossible to document the presence of Hauterivian-Aptian deposits in the succession. The Albian deposits are still terrigenous (predominantly clays, sometimes with sponge spicules). The Cenomanian transgressive deposits are coarser, and contain Conicorbitolina conica (d’Archiac), Rotalipora cushmani (Morrow) and Hedbergella-Praeglobotruncana sp. The following Turonian?-Campanian-Maastrictian deposits are micritic limestones with planctonic foraminifera in specific …


Wielician Foraminifera At The Western Border Of The Transylvanian Basin, Sorin Filipescu Mar 2012

Wielician Foraminifera At The Western Border Of The Transylvanian Basin, Sorin Filipescu

Studia UBB Geologia

Marine Middle Miocene deposits at the top of Gârbova de Sus Formation preserve a particular foraminifera assemblage, with both benthic and planktonic taxa. Presence of several biostratigraphic significant species allowed an extension of the known age of the formation, up to Wielician. The morphogroups also suggest a deeper environment, compared to the rest of the formation. The change of fauna type at this level might be correlated to the start of a new global cycle.


Upper Jurassic And Lower Cretaceous Sedimentary Formations From The Valcan Mountains (South Carpathians), Grigore Pop, Ioan I. Bucur Mar 2012

Upper Jurassic And Lower Cretaceous Sedimentary Formations From The Valcan Mountains (South Carpathians), Grigore Pop, Ioan I. Bucur

Studia UBB Geologia

The litho- and biostratigraphy of the Upper Jurassic-Lower Cretaceous formations cropping out in the southwestern part of Vâlcan Mountains is presented. Five formations were recognised in the studied area: Valea Pragurilor Formation, Valea Cheii Formation, Topeşti Formation, bioclastic-oolitic limestones from Sudoieşi valley and Izvarna Formation. The age of these formations is mainly based on foraminifera and calcareous algae.


Conodont Fauna And Biostratigraphy Of The Early-Middle Devonian Units In Beykoz, Şile And Kurtdoğmuş Areas, İstanbul, Turkey, Dilek Gülnur Saydam-Demi̇ray, Şenol Çapkinoğlu Feb 2012

Conodont Fauna And Biostratigraphy Of The Early-Middle Devonian Units In Beykoz, Şile And Kurtdoğmuş Areas, İstanbul, Turkey, Dilek Gülnur Saydam-Demi̇ray, Şenol Çapkinoğlu

Bulletin of the Mineral Research and Exploration

The conodont faunas defi ning the delta-pesavis zones (upper Lochkovian, Lower Devonian) were obtained from Beykoz and Karamandere sections of the İstinye Formation (the Yumrukaya group) and the conodont faunas of the laticostatus, serotinus, patulus and partitus zones (upper Emsian-lower Eifelian, Lower-Middle Devonian) were obtained from the Büyükdere and Kokarpınar sections of the Kozyatağı member of the Kartal Formation. A total of 22 species/subspecies were described belonging to the genera Neopanderodus (2), Icriodus (8), Pelekysgnathus (1), Lanea (1), Polygnathus (4), Ozarkodina (2), Pseudooneotodus (2), Belodella (2).


Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray Jan 2012

Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray

Turkish Journal of Earth Sciences

The studied Gülüç section of the Silurian Fındıklı Formation is situated on the western bank of Gülüç Creek in Ereğli, NW Anatolia, Turkey, in the eastern part of the Zonguldak Terrane. The Gülüç section consists of 3 sedimentary packages: greenish grey limy siltstones, 5-7 m thick (1), overlain by an irregular alternation of black shales and clayey limestones, about 15 m thick (2), and a 6-7 m thick succession of mainly siltstones and sandy limestones (3). A combined biostratigraphy based upon graptolites, cryptospores and conodonts indicates that Package 1 is of Llandovery (Rhuddanian, Aeronian and/or early Telychian) age, Package 2 …