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The northern Tethyan margin is a key region for determining environmental changes associated with the collision of continental and oceanic tectonic plates and Alpine orogeny. Herein we investigated Middle to Late Eocene neritic to bathyal sediments deposited during an interval of unstable climatic conditions. In order to quantify paleoenvironmental changes, we developed a detailed age model based on biozonations of planktic foraminifera, calcareous nannoplankton, and larger benthic foraminifera. The section at Adelholzen covers the almost complete Lutetian Stage (calcareous nannoplankton zones NP15a-16, planktic foraminifera zones E8-11, shallow benthic (foraminifera) zones SBZ13-15) and large parts of the Priabonian Stage (NP18-20, E14/15), while the intermediate Bartonian Stage (NP17) is completely missing. Foraminiferal, calcareous nannoplankton, and macrofossil assemblages were analyzed for changes in paleo-water depth, mixing and stratification, paleo-primary productivity (pPP), food supply, and bottom water oxygenation. Paleo-water depth estimates range from 50 m (middle neritic, early Lutetian) to nearly 500 m (upper bathyal, late Priabonian). The combination of assemblage composition, planktic and benthic foraminiferal accumulation rates, and derived parameters (carbon-flux to sea floor, pPP) enabled us to identify a series of distinct paleoceanographic events of at least regional significance. Such events are characterized by considerable changes in primary productivity or reduced bottom water ventilation. Calculated pPP-values indicate oligotrophic conditions throughout. [ABSTRACT FROM AUTHOR]

Reuter, M., Piller, W.E., Harzhauser, M., Kroh, A., Rögl, F. & Ćorić, S. 2010: The Quilon Limestone, Kerala Basin, India: an archive for Miocene Indo-Pacific seagrass beds. Lethaia, Vol. 44, pp. 76-86. The facies of the fossiliferous Quilon Limestone in SW India is described for the first time in detail at the Padappakkara-type locality. Facies (fossiliferous, micrite-rich, bioturbated sediment with intercalated sand pockets) and faunal composition (epiphytic foraminifers, seagrass feeding Smaragdia gastropods, bioimmuration of celleporiform bryozoan colonies) indicate a seagrass environment. The large discoidal archaiasin foraminifer Pseudotaberina malabarica, in particular, is considered as a proxy for seagrass communities. Recent seagrasses have their centre of generic richness in the Indo-Pacific where they cover wide areas in the tidal and shallow sub-tidal zones. However, their geological record is only fragmentary and their palaeobiogeographic distribution has a big stratigraphical gap in the Miocene Western Indo-Pacific region. The described nannoplankton flora and planktonic foraminifers from the Quilon Formation demonstrate that the deposition of the studied seagrass bed occurred in nannoplankton biozone NN3. This timing suggests formation during the closure of the Tethyan Seaway. The Quilon Limestone is thus an early Western Indo-Pacific seagrass bed and an important step in reconstructing the history of seagrass communities. □ Quilon Formation, Pseudotaberina malabarica, seagrass facies, Burdigalian, Indo-Pacific. [ABSTRACT FROM AUTHOR]

In the North Croatian Basin which is located in the southwestern part of the Pannonian Basin System, Miocene tuff deposits have been observed at several localities in the area of Banovina, Medvednica Mt. and Slavonia. Here we present new 40Ar/39Ar age results obtained from volcanic glass from the Laz tuff (15.42 ± 0.15 Ma) intercalated with lacustrine freshwater/brackish deposits, the Jovac tuff (15.10 ± 0.06 Ma) intercalated with lacustrine freshwater deposits, the Čučerje tuff (14.81 ± 0.08 Ma) and the Nježić tuff (14.40 ± 0.03 Ma) both deposited in a marine environment. Fossil data (calcareous nannofossils/foraminifera) from the underlying and overlying beds of the tuffs from Čučerje and Nježić match the geochronological data i.e. NN5 zone and M6 zone were determined. Integration of biostratigraphic and geochronological data enable a better understanding of the NCB sedimentary evolution and constrain the Middle Miocene marine flooding event in the marginal areas of the western part of the NCB at ~15 Ma i.e. early/middle Badenian boundary. These results together with the existence of lower Badenian marine sediments in the Sava depression (in the southern part of NCB) suggest it is possible to conclude that during the early Badenian in the NCB, freshwater lacustrine and marine environments coexisted. [ABSTRACT FROM AUTHOR]

During 2008. in the deposit of rock salt Tetima four exploratory boreholes: B-72, B-73, B-81 and B- 91 have been done. Sediments of the roof of salt formations have been drilled without coring and salt formation has been drilled with coring. Micropalaeontology sediments samples were taken from the sieve and the core drilling at the distance of 1-5 m. The main goal of the micropaleontologic research was to make biostratigraphic analysis of the salt roof and an attempt to define a new stratigraphic levels. On the basis of foraminifera it was defined the lower Badenian, which is divided into two local foraminiferal zones. The older part of the lower Badenian is presented by Ammonia viennensis and Nonion commune and the younger part of the lower Badenian makes the zone of Globigerinoides trilobus and Orbulina suturalis. These zones correspond to Lagenid zone of the Vienna basin. Within these zones the two new bench mark stratigraphic levels have been separated. The first is the immediate roof of salt formation and has a thickness of about 3 m, and the second level is 60-70 m above the salt formation and has a thickness of about 10 m. The first mark stratigraphic level is characterized by an extremely rare, dominantly planktonic foraminifera and lack of zoning type of Ammonia viennensis (d' ORBIGNY). The Second mark stratigraphic level is indicated by the presence of species Uvigerina macrocarinata PAPP & TURNOVSKY which is in the Central Paratethys related exclusively to the lower Badenian. This species on Tetima is represented in the boundary sediments of isolated foraminiferal zones. In laminated and thinly stratified dolomicrite of immediate substratum of rock salt some very rare foraminifera predominantly planktonic forms Globigerina praebulloides BLOW and Globigerina bulloides d ‘ORBIGNY have been found. Discovery of foraminifera in salt formation has confirmed the hypothesis about lagoon genesis and lower Badenian age of rock salt in Tuzla basin. The immediate roof of salt formation is presented with massive marls thickness of 65-80 m. About 3 m above the salt formation species Ammonia viennensis (d ‘ORBIGNY) emerges with the species Nonion commune (d ‘ORBIGNY) which together have the highest frequency and abundance in massive marls. It is interesting that shells of species Ammonia viennensis (d ‘ORBIGNY) are of orange colour and about three times larger than those in the upper Badenian. Above massive marls there are marls with interbeds of sandstones. These sediments with local foraminiferal zone Globigerinoides trilobus and Orbulina suturalis have a thickness of 220-242 m. Based on nannoplankton it was determined that the zone Ammonia viennensis and Nonion commune corresponds to zone NN5 (Sphenolithus heteromorphus zone by Martini, 1971), while zone Globigerinoides trilobus and Orbulina suturalis corresponds to upper part of zone NN5 and lower part of NN6 zone (Discoaster exilis zone by Martini, 1971). The results of these studies will be applied for the next investigations of salt formation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Faculty of Mining, Geology & Civil Engineering / Glasnik Rudarsko-gradevinskog fakulteta is the property of University of Tuzla, Faculty of Mining, Geology & Civil Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Faculty of Mining, Geology & Civil Engineering / Glasnik Rudarsko-gradevinskog fakulteta is the property of University of Tuzla, Faculty of Mining, Geology & Civil Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Paleoenvironmental analyses based on calcareous nannoplankton and foraminiferal distribution were carried out on samples from a locality at the village of Bogutovo near Ugljevik. During the middle Miocene, the region was positioned on the southern margin of the Pannonian Basin and the Central Paratethys Sea. The studied section is a sedimentary succession that is dominated by marine marls with a single limestone package near the middle. Samples from borehole UI568 were also studied. All assemblages are dominated by small reticulofenestrids, with lesser numbers of Coccolithus pelagicus, Helicosphaera carteri, H.walbersdorfensis, Holodiscolithus macroporus, Reticulofenestra gelida, R.seudoumbilicus, Sphenolithus moriformis and Umbilicosphaera jafari. Braarudosphaera bigelowii, Calcidiscus leptoporus, Coronocyclus nitescens, Coronosphaera mediterranea, Cyclicargolithus floridanus, Geminilithella rotula, Pontosphaera multipora, Rhabdosphaera sicca and Syracosphaera pulchra are rare but continuous in occurrence. Above the nonmarine Oligocene sediments from the borehole are sediments that contain some unidentified nannoplankton taxa. Continuous occurrences of the calcareous nannoplankton zonal marker Sphenolithus heteromorphus and the absence of Helicosphaera ampliaperta in the middle and the upper part of the section allow placement in Zone NN5. The last occurrence of S. Heteromorphus indicates that the Zone NN5/NN6 boundary can be placed in the top portion of the studied interval. Using the standard Central Paratethys ecozones for benthic foraminifera, the analyzed time interval includes two zones: the early Badenian (Moravian) upper Lagenidae Zone and the middle Badenian (Wielician) Spirorutilus carinatus Zone. [ABSTRACT FROM AUTHOR]

An abstract of the article "Middle Miocene freswater ostracods from the Aflenz Basin (Eastern Alps, Austria)," by Irene Zorn and Stjepan Ćorić is presented.

In the Styrian Basin, early Miocene marine sedimentation of the Karpatian (upper Burdigalian) ended with basin shallowing, marked regression and tectonic movements. The Karpatian sedimentation cycle corresponds to the global 3rd order cycle TB 2.2, followed by the Bur5/Lan1 sea-level fall. This regression was combined with tectonic movements (the Styrian Tectonic Phase), seen in the Styrian Unconformity by an angular discordance at the Wagna and Katzengraben outcrops and also in deep wells. Sediments of the first middle Miocene (Badenian/Langhian) transgression are commonly eroded or reduced in thickness at the basin borders. In the basin center, the bathyal environment continues from the Karpatian to the Badenian. Sediments of the first Badenian transgression have been dated by calcareous nannoplankton as NN4 and correlated by the occurrence of Praeorbulina sicana with the basal Langhian. The 3rd order sequence corresponds to TB 2.3. The erosional phase of the sea-level fall Lan2/Ser1 can only be observed in near-shore facies, followed by transgressive beds within Zone NN5, which represents the second, main Badenian transgression in the Central Paratethys and corresponds to the long global cycle TB 2. The highstand system tract of this cycle is expressed in carbonate build-ups of the Weissenegg Formation. According to the global 3rd order sequences, the youngest sediments of the Retznei section (< 14.39 Ma) overlying the carbonate buildups belong to the falling-stage system tract of TB2, but did not record regression, but instead continuous deepening of the Styrian Basin, indicating strong subsidence during the early middle Miocene. [ABSTRACT FROM AUTHOR]

The Eggerding Formation, typically about 45 m thick, forms part of the deep marine Oligocene succession in the Molasse Basin, which comprises from bottom to top the Schöneck (formerly "Fish Shale"), Dynow ("Bright Marlstone"), Eggerding ("Banded Marl") and Zupfing formations ("Rupelian Marl"). The Eggerding Formation and the lower part of the Zupfing Formation have been studied using core and cuttings samples and a multidisciplinary approach involving core description, geochemistry, palynology and nannopaleontology. The Dynow Formation and the lower part of the Eggerding Formation were deposited during nannoplankton zone NP23 (Martini, 1971). The transition between the Dynow and Eggerding formations is characterized by a gradual decrease in carbonate contents. The Eggerding Formation deposited in near-shore environments contains several sand layers. In contrast, the Eggerding Formation deposited along the northern slope is generally poor in sand. Its lower part consists of dark grey laminated shaly marlstone with white bands rich in coccolithophorides. TOC contents are about 5 %. The upper part of the Eggerding Formation consists of a homogenous sequence of marly shale and includes in average 1.6 % TOC. Oxygen deficient conditions prevailed during deposition of the Eggerding Formation. Marine palynomorphs are present in all samples from the Eggerding Formation, but calcareous nannoplankton is restricted to its lower part. Salinity variations are recorded in rocks of the lower part of the Eggerding Formation. The environment during deposition of its upper part was more stable. Log signatures, which are comparable over tens of kilometres, provide evidence for the lateral continuity of the Eggerding Formation deposited on the upper slope. Slope instabilities are indicated by slumps and extensive submarine slides. Sliding reached a maximum at the transition from the Eggerding to the Zupfing Formation, when locally a succession up to 70 m thick was removed from the northern slope. The slided material was redeposited either on the northern slope or at the base of the slope. The Eggerding Formation is overlain by the Zupfing Formation (NP24), consisting of clay marl up to 450 m thick. Oxygen-depleted conditions continued during deposition of the Zupfing Formation, but only the lowermost few meters of the Zupfing Formation ("Transition Zone") are rich in organic matter (1.5 % TOC). Whereas the lower part of the Eggerding Formation (TOC 1.9-6.0 %; HI up to 600 mg HC/g TOC) holds a very good source potential for oil (and gas), its upper part and the Transition Zone (TOC: ∼1.5 %; "true" HI 500-600 mg HC/g TOC) are characterized by a good potential. Biomarker data suggest that the latter contributed significantly to the Molasse oils. In contrast, the contribution of the Dynow Formation and the lower Eggerding Formation was minor. [ABSTRACT FROM AUTHOR]