Abstract. The Tarcău Nappe is the most important unit of the Carpathian flysch due to its size, stratigraphic and tectonic complexity. Our purpose was to identify the major types of foraminifera assemblages in relation to the paleoenvironmental settings and their biostratigraphic potential. The identified assemblages are characteristic to the Cretaceous and Paleogene, consisting mostly of benthic agglutinated and, in lower proportions, benthic calcareous and planktonic species. Local abundances of Glomospira allowed the correlation of the examined strata to the early Eocene "Glomospira event" described from the Carpathians in Poland, Morocco, and Labrador. Rzehakina fissistomata (Grzybowski) identified at Palma makes possible the correlation of these deposits to the Paleocene Rzehakina fissistomata Zone. Paleoenvironmental conditions (depth, amount of oxygen, nutrients) could be inferred based on specific assemblages and compared to the already described types of facies from the Carpathians.
Abstract. Middle Eocene foraminiferal assemblages have been analyzed from three representative sections of bathyal deposits cropping out along the Brodina Valley and Voroneţ Valley in the northern part of the Tarcău Nappe (Eastern Carpathians, Romania). The foraminiferal assemblages are dominated by coarsely agglutinated taxa characteristic of the "flysch -type" foraminiferal biofacies. The depositional setting was probably upper to middle bathyal, as suggested by the abundance of the tubular forms. The morphogroup analyses showed variations in tubular and infaunal morphotypes, suggesting fluctuations in the organic matter input, oxygenation, and disturbing bottom water currents. Based on the presence of Ammodiscus latus, Reticulophragmium amplectens, Haplophragmoides parvulus, Spirosigmoilinela compressa, Psamminopelta gradsteini and the high abundances of Reophax pilulifer, the studied deposits can be assigned to the upper part of the middle Eocene.
Foraminiferal and cal car e ous nannofossil as sem blages from the East ern Carpathians (north ern part of the Tarcãu Nappe, Ro ma nia) were doc u mented and cor re lated in or der to re con struct the palaeonvironmental set tings and pro vide a biostratigraphic frame work of the Plopu For ma tion. The ben thic foraminiferal as sem blages are dom i nated by flysch-type agglu ti nated taxa, sug gest ing a bathyal palaeodepth with fre quent os cil la tions of the car bon com pen sa tion depth. The ag glu tinated foraminifera morphogroup anal y ses sug gest dif fer ent lev els of or ganic mat ter in flux and ox y gen a tion. Both the foraminifera and cal car e ous nannofossil as sem blages sug gest a shift be tween the warm Mid dle Eocene to the cooler Late Eocene cli mate. Biostratigraphic data based on cal car e ous nannofossils (NP15-NP19/NNTe8-NNTe12 biozones) helped to es tab lish the age of the for ma tion. Four as sem blages of ben thic ag glu ti nated foraminifera (Psammosiphonella cylindrica-No thia excelsa; Paratrochamminoides spp.-Trochamminoides spp.; Karrerulina spp.-Reticulophragmium amplectens; Spiroplectammina spectabilis) cor re lated with cal car e ous nannofossil bioevents sup ported the place ment of the Middle to Late Eocene tran si tion within the Plopu For ma tion.
. Palaeoenvironmental changes in the Transylvanian Ba sin dur ing the Early Mio cene re vealed by the foraminifera as sem blages. Geo log i cal Quar terly, 60 (1): 167-180, doi: 10.7306/gq.1245The evo lu tion of the Transylvanian Ba sin dur ing the Early Mio cene has been re con structed from the suc ces sion of palaeoenvironments in ferred from sedimentological trends and the suc ces sion of spe cific foraminiferal as sem blages from Lower Mio cene Tihãu sec tion in the north west ern Transylvanian Ba sin. Plank tonic foraminifera sug gest a Burdigalian age and re cord sea level changes, cli ma tic and pro duc tiv ity events. Ben thic foraminifera of fer data on the palaeoenvironmental evo lu tion, with a large-scale progradational (coars en ing up) sed i men tary suc ces sion in flu enced by re gional tec ton ics. The suc ces sion of depositional events in cludes: (1) transgressive coarse grained de pos its with typ i cal Med i ter ra nean as semblages of bi valves in beach en vi ron ments; (2) a glauconitic fa cies which can be as so ci ated with the max i mum flood ing surface of the trans gres sion; (3) sed i men ta tion con tin ued on a nar row shelf in flu enced by del tas dur ing the highstand; (4) the in flu ence of re gional tec ton ics and sub se quent fill ing with turbidites as so ci ated with fan del tas.
Late Cretaceous foraminiferal and calcareous nannoplankton assemblages from the northern part of the Tarcău Nappe, Hangu Formation in the northern Eastern Carpathians are documented in order to reconstruct paleoenvironmental settings and biostratigraphy. The foraminiferal assemblages are dominated by flysch-type agglutinated taxa suggesting bathyal environments, close to the calcite compensation depth (CCD), and mesotrophic to oligotrophic conditions. The morphogroup analyses display variations in tubular and infaunal morphotypes suggesting different levels of oxygenation and seafloor disturbance caused by currents. Reddish hemipelagites containing only agglutinated foraminifera (dominant infaunal forms) occurring in the middle part of the section suggest an increase of water depth and changes in redox conditions. Based on foraminifera, the deposits were assigned to planktonic Globotruncana ventricosa and agglutinated Caudammina gigantea Zones. The first occurrence of Uniplanarius trifidus and last occurrence of Reinhardtites anthophorus demonstrate the presence of Late Campanian UC15 c TP -UC16/CC21-CC23 calcareous nannoplankton Zones. Foraminiferal and nannofossil assemblages in the red beds have a high potential for stratigraphic correlation on a regional scale.
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