Studia UBB Geologia

Monographic study of the Late Cretaceous representatives of the bolivinoidid benthic foraminifera

Marius Dan Georgescu — Fri, 13 Apr 2018 12:55:50 PDT

A high resolution taxonomy and classification framework is developed for the representatives of the calcareous benthic foraminiferal family Bolivinoididae; this family consists of 24 species assigned to three genera. This new classification includes data pertaining of the test ultrastructure, ornamentation and porosity, which are obtained with the aid of careful and extensive study of the specimens under the scanning electron microscope. Two new taxa are described: Bolivinoides antiquum – n. sp. and Swiecickina – n. gen. A biostratigraphical framework consisting of eleven biozones based on bioevents given by species of the genera Bolivinoides and Swiecickina is developed for the middle Santonian-Maastrichtian stratigraphical interval; its resolution is more than double when compared to those of the previously developed biostratigraphical frameworks based on the representatives of this group.

Upper Cretaceous planktic foraminiferal biostratigraphy

Marius Dan Georgescu — Fri, 15 Sep 2017 10:42:01 PDT

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 data in applied studies.

Paleocene "flysch-type" agglutinated foraminifera from the northern part of the Eastern Carpathians (Romania)

Raluca Bindiu-Haitonic et al. — Mon, 14 Nov 2016 11:26:01 PST

Representative assemblages of agglutinated foraminifera from the Paleocene deposits of the Suha outcrop in the Tarcău Nappe (Eastern Carpathians, Romania) were analyzed using diversity indices, morphogroups and foraminiferal biofacies in order to describe the paleoenvironmental and palaeobathymetrical conditions of the studied area. The results suggest bathyal environments, close to the Carbonate Compensation Depth (CCD) and a flysch type biofacies. The assemblages are dominated by coarsely agglutinated flysch-type taxa: tubular (Nothia, Rhizammina, Rhabdammina), globular (Saccammina), flattened planispiral and streptospiral (Rzehakina) and flattened streptospiral forms (Paratrochamminoides and Trochamminoides). The agglutinated foraminifera morphogroups display variations through the section suggesting changes in the amount of organic matter, oxygen and seafloor disturbance caused by the local influence of the turbiditic flows. Based on the presence of the index taxa Rzehakina fissistomata throughout the entire section, the deposits were assigned to the Paleocene Izvor Formation.

Geochemical investigation of Neogene volcaniclastic rocks from the south-eastern part of the Zărand Basin (Apuseni Mts., Romania) – implications for locating the source area

Luminiţa Zaharia et al. — Tue, 02 Aug 2016 12:30:54 PDT

A geochemical study of the Neogene volcaniclastic deposits from the south-eastern part of the Zărand Basin (Apuseni Mts., Romania) was performed. The investigated rocks are represented by medium-K calc-alkaline andesites. Their geochemical features are similar with those of other Neogene volcanic rocks from the Apuseni Mts. However, the investigated rocks also display a few particularities: limited variation of some major oxides and trace elements content, much lower content of Nb or of light REE. As for the other Neogene volcanic rocks from Apuseni area, the geochemical evidence supports a magma source located close to the boundary between crust and garnet-free lithospheric mantle, minor fractional crystallization processes affecting the magma. A subduction signature was identified for the investigated samples, and, similar to other Neogene volcanic rocks from Apuseni Mts., was interpreted as being related to some enrichment in fluids of the magma source. Based on the location and geochemical similarities with those of other Neogene volcanic rocks from the Apuseni Mts, the assumed age range of volcanic activity generating the volcaniclastic rocks of the study area is 13.8-10 Ma, while the source of the volcaniclastic material is most probably the Bontău volcanic structure.

A Middle Miocene rhinoceros find in Transylvania: 19^th century forgotten correspondence

Vlad A. Codrea et al. — Thu, 21 Apr 2016 12:11:20 PDT

The single report in Romania of the Middle Miocene rhinoceros Brachypotherium brachypus, a rare species in our country or elsewhere in Europe, is from Petros locality in Hațeg basin. This find is an old one, nearly a century and half ago. A fragmentary letter written by the Hațeg naturalist Ádám Buda to Prof. Antal Koch retrieved in the Paleontological Museum of Babeș-Bolyai University Cluj-Napoca brings some light about this find. The letter was probably written around 1881-1882 and reveals the active exchanges of scientific data between the professor from Cluj and country people interested in natural sciences.

Review “A memoir of my life and work”, Bica Ionesi, Junimea Publishing House, Iaşi, 2015

Ioan Mârza — Mon, 04 Apr 2016 11:51:37 PDT

Calcareous nannofossils- and ammonites-based biostratigraphy of the Baghamshah Formation (Central Iran Basin, Iran)

Mădălina-Elena Kallanxhi et al. — Tue, 29 Mar 2016 12:02:24 PDT

Middle Jurassic calcareous nannofossils and ammonite assemblages from the Baghamshah Formation are described here, cropping out east of Semnan locality (Central Iran Basin, Iran). Low diversity and abundance characterize the nannofossil assemblages, which are dominated by genera belonging to the Family Watznaueriaceae. The calcareous nannofossil assemblages lack the usual markers for the Callovian interval, making difficult the age attribution. Ammonite assemblages display low diversity and poor preservation. From a biostratigraphical point of view, nannofossil assemblages would suggest that the material studied belongs to the NJT12 Zone from the Tethyan / sub-Mediterranean province and to the NJ12b subzone - lower NJ13 Zone from the Boreal province, correlating to the ammonite Tethyan / sub-Mediterranean Gracilis Zone and to the Boreal / sub-Boreal Koenigi - Calloviense Zones, yielding a Lower Callovian biostratigraphical distribution.

Late Holocene palaeohydrological changes in a Sphagnum peat bog from NW Romania based on testate amoebae

Andrei-Cosmin Diaconu et al. — Tue, 12 Jan 2016 08:19:27 PST

This paper investigates the possibility of reconstructing the palaeohydrological changes in an active Sphagnum peat bog from north-western Romania using testate amoebae fauna and organic matter content determined by loss on ignition (LOI). In total 28 taxa of testate amoebae were identified of which 11 were frequent enough to present a remarkable ecological significance. Based on the relative abundance of these taxa nine zones were identified, crossing from very wet to dry climate conditions. The wet periods identified are characterized by taxa like Centropyxis cassis, Amphitrema flavum and Hyalosphenia papilio, while in the dry periods Difflugia pulex and Nebela militaris thrive. We showed that combining qualitative information regarding hydrological preferences with the quantitative percentage data from the fossil record it is possible to obtain information regarding major surface moisture changes from the peat bog surface. Furthermore we identified a link between distribution of testate amoebae assemblages, organic matter variation and minerogenic material.

Late Oligocene calcareous nannofossils from Albanian-Thessalian intramontane basin (Bozdovec Section, Albania) – a quantitative approach

Mădălina-Elena Kallanxhi et al. — Tue, 22 Dec 2015 12:39:41 PST

Quantitative and semi-quantitative analyses of calcareous nannofossils were performed on samples collected from Bozdovec Section (Albanian-Thessalian intramontane basin, Albania). The calcareous nannofossil assemblages are dominated by: small reticulofenestrids, Cycligargolithus floridanus, Coccolithus pelagicus, Sphenolithus spp., Reticulofenestra scrippsae, Helicosphaera spp., Clausicoccus spp., Reticulofenestra bisecta, Cycligargolithus abisectus. Biostratigraphically, the studied outcrop is assigned to the Late Oligocene NP25 - Sphenolithus ciperoensis Zone. In the Mediterranean area, this interval can be correlated with the MNP25a - Sphenolithus ciperoensis Zone, while according to the zonation for low to middle latitudes the investigated material would belong to the CNO5 - Sphenolithus ciperoensis TZ. High amounts of small reticulofenestrids and sphenoliths point to warm well stratified paleoenvironment.

Foraminiferal biostratigraphy and paleoenvironments of the middle Eocene deposits from the northern part of the Tarcău Nappe (Eastern Carpathians, Romania)

Raluca Bindiu et al. — Thu, 13 Aug 2015 12:58:45 PDT

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 agglutinated species with tubular forms (Psammosiphonella cylindrica, Nothia spp., Bathysiphon sp.), globular (Saccammina spp., Psammosphaera spp.), coiled (Recurvoides spp., Reticulophragmium spp.) and flattened streptospiral (Paratrochamminoides spp., Trochamminoides spp.). Coarsely agglutinated taxa are characteristic for the “flysch – type” agglutinated 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.

New data on the Early - Middle Badenian transition in the NW Transylvanian Basin (Romania) revealed by the planktonic foraminifera assemblages

Rodica Filipescu et al. — Mon, 06 Jul 2015 13:35:05 PDT

The planktonic foraminifera assemblages recovered from two cores drilled in Cluj-Napoca (NW Transylvanian Basin) demonstrate connections of the basin to the open seas before the middle Badenian evaporite deposition. Assemblages suggest clear changes in the environments, with an initial transgressive trend, followed by a decrease in the rate of sea-level rise, and finally a sea-level fall. The occurrence of planktonic foraminifera (mainly Globorotalia) offers a good potential for correlation of the pre-evaporitic interval with the uppermost Langhian and can be used for tracing the early-middle Badenian boundary.

Middle to Late Holocene vegetation shifts in the NW Transylvanian lowlands (Romania)

Roxana Grindean et al. — Thu, 04 Dec 2014 12:15:09 PST

The Iaz peat bog, located in northwestern Transylvania at 300 m a.s.l., was cored to study the Middle to Late Holocene vegetation shifts in the area. The pollen record is supported by seven ¹⁴C datings. The base of the sequence starts in the Middle Holocene, when the outer woodlands were dominated by Corylus avellana together with other components of the Quercetum mixtum. The local establishment of Carpinus betulus occurred at 5700 cal. yr BP with maximum values at around 4900 cal. yr BP. At 4800 cal. yr BP, Fagus sylvatica became locally established and expanded, possibly as a result of moist climatic conditions and dominated the mesothermophilous woodlands from 4300 cal. yr BP onwards. During the periods of greater moisture, the deciduous forest was overgrown by the hygrophilous Alnus glutinosa belt. Indications of human activities in the area were recorded since 6300 cal. yr BP, when Cerealia and Secale pollen and other ruderal taxa start to appear regularly throughout the sequence. Although intense at times, the anthropogenic factor only played a major role in the vegetation changes during the last 635 years.

Dasycladalean algae from Upper Jurassic–Lower Cretaceous limestones of Piatra Craiului Massif (South Carpathians, Romania) and their relationship to paleoenvironment

Cristian Victor Mircescu et al. — Mon, 16 Jun 2014 07:12:35 PDT

The Mesozoic limestones of Piatra Craiului Massif were deposited in the Dâmbovicioara sedimentary area, at the eastermost part of the Getic carbonate platform. In order to study the microfacies and to provide a more detailed biostratigraphy, we sampled the carbonate succession from Piatra Craiului Massif along several sections. The identified microfacies point to reef slope, carbonate platform margin or restrictive, lagoon-type internal depositional environments. Some of the identified microfossils are biostratigraphic markers for the Tithonian-Lower Valanginian. The calcareous algae form associations typical for reef slopes and internal platforms. The latter can be subdivided into: (1) restrictive environments (low-energy subtidal-intertidal), dominated by rivulariacean-type cyanobacteria, and (2) open-marine environments (moderate to high-energy subtidal) where dasycladalean algae are more frequent.

In memoriam: Academician Prof. Dr. doc. Radu Dimitrescu

Ioan Mârza — Thu, 27 Feb 2014 09:10:29 PST

Historical Romanian meteorites: emendations of official catalogue records

Dana Lüttge-Pop et al. — Fri, 17 Jan 2014 10:31:33 PST

With its more than 50,000 valid official and provisory meteorite entries, the online catalogue of The Meteoritical Society, i.e., the Meteoritical Bulletin Database (MBDB) represents the most authorized and primary source of information in the field. Unfortunately, this official reference contains some erroneous geographical information in the case of five historical Romanian meteorites. For Zsadany, the current country information is “Hungary, Bekes county” instead of Romania, Timiş County. For Mezö-Madaras and Tauti, the county affiliations “Harghita” and respectively “Cluj” have to be corrected into Mureş and Arad, respectively. Geographical coordinates for Kakowa and Ohaba require minor corrections, only.

The source of these errors resides in changes of names and administrative affiliations of the localities of the fall/find, while the formal nomenclature protocol requires the meteorite name in the original description to be preserved. The example of the historical Romanian meteorites illustrates the challenges that a researcher unfamiliar with a region faces when locating old specimens, in general. This requires knowledge of regional history and geography, and sometimes access to the original references - usually not written in English, or having a somehow limited circulation.

Additionally, in the last two decades several new publications provided more detailed classification information on Sopot, Ohaba, Tauti and Mocs meteorites. Sopot was classified as H5, with shock stage S3. The studied Ohaba and Tauti samples also attested S3 shock stages. Variable shock stages (S3-5) were identified in Mocs samples, the most well-known Romanian meteorite. This new information should be added to the corresponding MBDB entries.

Sedimentary deposition of Bozeş Formation (Apuseni Mts., Romania) – detrital zircon dating and micropaleontological ages

Ramona Bălc et al. — Fri, 17 Jan 2014 10:31:31 PST

In order to establish the age of the Bozeş Formation, which crops out in the SE Apuseni Mts., calcareous nannofossils investigations and U-Pb detrital zircon dating were performed on Stăuinii Valley deposits. The results were correlated, and further compared with previous fossil age data. The U-Pb detrital zircon age spectrum reveals a consistent Upper Cretaceous grain population, which yielded an age of 83 Ma (concordia age of 82.87±0.59 Ma), interpreted as the maximum deposition age, thus, marking the Lower Campanian as the initiation of sediment deposition. Based on the presence of some important taxa in the calcareous nannofossils assemblage, the age of studied deposits were assigned to Upper Santonian? – upper Upper Campanian. The Upper Santonianage is presumed by the presence of curved Lucianorhabdus cauyeuxii, reworked from older deposits. The Campanian stage is confirmed by the presence of Broinsonia parca parca, Broinsonia parca constricta and rare specimens of Ceratolithoides aculeus and Uniplanarius sissinghii. Both Reinhardtites anthophorus and Eiffelithus eximius indicate that the upper part of the Stăuinii section is ending in CC22 / UC15_d^TP – UC15_e^TP Subzones, thus in upper Upper Campanian. FO of Eiffellithus parallelus points to the same age. The calcareous nannofossils assemblages do not sustain the presence of the Lower Maastrichtian deposits on Stăuinii Valley, as mentioned by few previous studies based on Pachydiscus neubergicus.

New advances in understanding the heterohelicid planktic foraminifer early evolution

Marius D. Georgescu — Mon, 28 Oct 2013 08:35:52 PDT

Three Late Cretaceous lineages of heterohelicid planktic foraminifera, which evolved in the proximity of the Cenomanian/Turonian boundary, bring new data in understanding the group evolutionary history. Lunatriella Eicher and Worstell 1970a is a directional lineage of late Cenomanian-early Turonian age, which gradually develops peripheral backward extensions in the last-formed chambers. Steineckia Georgescu 2009a of the Turonian is the earliest heterohelicid lineage that evolved ornamentation consisting of pore mounds; a gap spanning the latest Turonian-early Santonian separates it from Laeviheterohelix Nederbragt 1991 of the late Santonian-Campanian, the second lineage that developed ornamentation consisting of pore mounds. Pseudoplanoglobulina Aliyulla 1977 evolved in the early Turonian and is the first heterohelicid lineage that developed multichamber growth in the adult stage; it became extinct in the Santonian. The three directional lineages show that the iterative and convergent evolution patterns occur extensively in the early heterohelicid history.

Mineralogical data on bat guano deposits from three Romanian caves

Alexandra Giurgiu et al. — Wed, 16 Oct 2013 10:05:50 PDT

Mineralogical studies performed on crusts, nodules and earthy masses from the Romanian caves Gaura cu Muscă, Gaura Haiducească and Peștera Zidită have revealed the presence of three different phosphate associations. The minerals have been identified by means of X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. Five phosphates have been identified in the samples, with hydroxylapatite the only common mineral in all the three caves. Brushite, taranakite, leucophosphite and variscite are the other phosphates identified. Associated minerals include gypsum, calcite, quartz and illite-group minerals. Aside from differences in the lithology, the occurrences of the different phosphate minerals indicate variable pH and humidity conditions near or within the guano accumulations.

Bioerosive structures in orbitolinid foraminifera: examples from the Lower Cretaceous of Central Iran

Felix Schlagintweit et al. — Thu, 03 Oct 2013 07:47:08 PDT

Lower Cretaceous orbitolinid assemblages from Central Iran yield various bioerosional structures. The omnipresent traces of different boring taxa and groups (e.g., sponges, calcimicrobes, incertae sedis) represent a characteristic feature of the investigated thin-section material. The assemblage can be attributed to the Entobia ichnofacies dominated by borings assigned to the activity of sponges. The boring galleries are often concentrated in a plane parallel to the test surface, along the boundary of the marginal and the central zone of the orbitolinid tests. The borings are observed in foraminiferan-dasycladalean wackestones to poorly washed-out packstones, which can be referred to a subtidal palaeoenvironment.

Sedimentology and biostratigraphy of the Early-Middle Miocene transition in NW Transylvanian Basin (Pâglişa and Dej sections)

Claudia Beldean et al. — Tue, 06 Aug 2013 06:46:03 PDT

The Early - Middle Miocene transition can be studied in several sections from the north-western Transylvanian Basin, across the boundary between the Hida and Dej Formations. The Pâglişa and Râpa Dracului (Dej locally outcrop) sections offer a very good record of the changes in the sedimentary facies and micropaleontological content across the boundary. The lower parts of the sections display the upper Hida Formation with prodelta fine grained sediments covered by coarser grained sediments related to a delta front progradation. Four sedimentary facies associations have been separated based on grain size and associated sedimentary structures. Micropaleontological assemblages are moderately to poorly preserved, with a low abundance and diversity. Planktonic Streptochilus pristinum is the main taxon associated with rare (< 10%) calcareous benthic foraminifera (Bulimina, Bolivina, Cibibicidoides). The Dej Formation consists of stacked channel lag deposits associated with lateral accretion bars and crevasse splays followed by fall-out tuffs and redeposited low density tuffites interbedded with low density fine siliciclastics. The deposits of Dej Formation from the investigated areas were separated in four facies associations based on grain size/petrography and primary sedimentary structures. Micropaleontological assemblages contain typical early Badenian planktonic foraminifera (species of Orbulina, Praeorbulina, Globigerinoides, and Globorotalia) associated to the main phase of the marine transgresion from the beginning of the Middle Miocene.