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Upper Cretaceous Planktic Foraminiferal Biostratigraphy, Marius Dan Georgescu
Upper Cretaceous Planktic Foraminiferal Biostratigraphy, Marius Dan Georgescu
Studia UBB Geologia
A high-resolution biostratigraphical zonation based on planktic foraminifera is developed for the Upper Cretaceous. It consists of twenty-five biozones defined with the aid of serial and coiled planktic foraminiferal taxa and presents the highest resolution developed with planktic foraminifera for this Series. All the index species used in biozonation are part of the practical classification associated with the evolutionary classification. The new biozonation represents a first in using data directly derived from the Theory of Evolution and its evolutionary classification extension in an application of paleontology such as biostratigraphy. By this the Theory of Evolution becomes a direct provider of …
New Data On The Western Transylvanides Along The Ampoi Valley (Southern Apuseni Mts., Romania), Erika Suciu-Krausz, Ramona BăLc, Florin Borbei
New Data On The Western Transylvanides Along The Ampoi Valley (Southern Apuseni Mts., Romania), Erika Suciu-Krausz, Ramona BăLc, Florin Borbei
Studia UBB Geologia
In order to clarify some of the issues regarding the mineralogical content and the source area of the Cretaceous deposits from Ampoi Valley basin (Southern Apuseni Mountains) fourteen lithologic logs were drawn from the Ampoi Valley both side tributaries (Slatinii, Ruzi, Vâltori, Valea lui Paul, Feneş, Călineasa, Fierului Brook, Bobului, Satului, Tăuţi, Galaţi, Presaca Ampoiului, Valea Mică and Valea Mare brooks). The main sedimentary rock types were identified (conglomerates, wacke and lithic sandstones, clays, and marls). The sandstones were classified according to the ternary diagrams. Their petrographic features revealed both a magmatic and a metamorphic source area for them.
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
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 …
Upper Cenomanian – Lower Turonian (Cretaceous) Calcareous Algae From The Eastern Desert Of Egypt: Taxonomy And Significance, Ioan I. Bucur, Emad Nagm, Markus Wilmsen
Upper Cenomanian – Lower Turonian (Cretaceous) Calcareous Algae From The Eastern Desert Of Egypt: Taxonomy And Significance, Ioan I. Bucur, Emad Nagm, Markus Wilmsen
Studia UBB Geologia
An assemblage of calcareous algae (dasycladaleans and halimedaceans) is described from the Upper Cenomanian to Lower Turonian of the Galala and Maghra el Hadida formations (Wadi Araba, northern Eastern Desert, Egypt). The following taxa have been identified: Dissocladella sp., Neomeris mokragorensis RADOIČIĆ & SCHLAGINTWEIT 2007, Salpingoporella milovanovici RADOIČIĆ 1978, Trinocladus divnae RADOIČIĆ 2006, Trinocladus cf. radoicicae ELLIOTT 1968, and Halimeda cf. elliotti CONARD & RIOULT, 1977. Most of the species are recorded from the first time from Egypt. Three of the identified algae (T. divnae, S. milovanovici and H. elliotti) also occur in Cenomanian limestones of the Mirdita zone, Serbia, …
On The Cretaceous Occurrences Of Ammogloborotalia Zheng, 2001 (Foraminifera), Michael A. Kaminski, Claudia Cetean, Andrew Henderson, Sorin Filipescu
On The Cretaceous Occurrences Of Ammogloborotalia Zheng, 2001 (Foraminifera), Michael A. Kaminski, Claudia Cetean, Andrew Henderson, Sorin Filipescu
Studia UBB Geologia
Three species of agglutinated foraminifera from Cretaceous deep-water deposits that have been described as trochamminids are here transferred to the genus Ammogloborotalia ZHENG, 2001. These species are Trochammina abrupta GEROCH, 1959; Trochammina quinqueloba GEROCH, 1959, and Ammoanita globorotaliaeformis Gradstein and Kaminski, 1999. A fourth species, Ammogloborotalia sp.1, which is probably a new species from the Turonian of the southern East Carpathians of Romania is reported here for the first time. We hereby extend the known stratigraphic range of the genus Ammogloborotalia to the Late Jurassic (Tithonian).
Biostratigraphy Of The Cretaceous Deposits In The Western Transylvanides From Ampoi Valley (Southern Apuseni Mountains, Romania), Ramona Balc, Erika Suciu-Krausz, Florin Borbei
Biostratigraphy Of The Cretaceous Deposits In The Western Transylvanides From Ampoi Valley (Southern Apuseni Mountains, Romania), Ramona Balc, Erika Suciu-Krausz, Florin Borbei
Studia UBB Geologia
The present study is an approach of the issues related to the biostratigraphy of the Western Transylvanides. The research provided exact age data for the Feneş Formation, Valea lui Paul Formation, Bozeş Formation and Râmeţi Formation. The age of the formations was established based on the calcareous nannoplankton assemblages in Barremian-Campanian range. The lithological features together with the new age data allowed us to modify the boundaries between formations; accordingly the knowledge on the structure of South Apuseni Mountains required changes, too. The new data also imply the modification of the existent geological maps of the region. Based on the …