Miocene deep-water agglutinated foraminifera from the Lomonosov Ridge and the opening of the Fram Strait

Deep-water agglutinated Foraminifera (DWAF) were recovered from Miocene to Pliocene sediments in 103 samples from IODP Hole M0002A on the Lomonosov Ridge. The First Occurrence of DWAF in Hole M0002A is observed just above the color change corresponding to the boundary between Lithological Subunits 1/4 and 1/5 in Core section –44X-1. The foraminiferal record of Hole M0002A consists entirely of agglutinated benthic species, largely sparse assemblages containing Cyclammina pusilla and Alveolophragmium polarensis. The faunal succession in Hole M0002A is subdivided into three assemblages based on the stratigraphic ranges of characteristic taxa: (1) a relatively diverse assemblage at the base of Lithological Subunit 1/4 (Cores 44X-1 to –38X), with abundant agglutinated foraminifera including Reticulophragmium pusillum and Ammolagena clavata, indicating connections with the North Atlantic. This assemblage displays the best preservation, which is here attributed to higher concentrations of dissolved silica in pore waters (2) A less diverse assemblage characterized by Alveolophragmium polarensis with Adercotryma agterbergi, in the lower part of Lithological Subunit 1/3 (Cores –38X to –35X); (3) a sparse residual assemblage within Lithological Subunit 1/3 with Rhabdammina spp., A. polarensis and R. pusillum indicating poor preservation of organically-cemented DWAF in Cores –34X to –10X. A comparison of the DWAF assemblages from the Lomonosov Ridge with previously studied Miocene assemblages from ODP Hole 909C in the Fram Strait, Norwegian-Greenland Sea (Kaminski et al. 2005), suggests that the inflow of Atlantic intermediate water into the Arctic Ocean began prior to 17.5 Ma

Miocene deep-water agglutinated Foraminifera from ODP Hole 909c: Implications for the paleoceanography of the Fram Strait Area, Greenland Sea

Deep-water agglutinated Foraminifera (DWAF) are investigated from Miocene sediments recovered from ODP Hole 909C in the Fram Strait, Norwegian-Green land Sea. We studied 125 samples from Cores 909C-50R to -103R. and recovered over 60 species of DWAF. The faunal succession in Hole 909C is subdivided into three assemblages based on the stratigraphic ranges of characteristic cosmopolitan taxa. These are: (1) a diverse Reticulophraginium amplectens - Reophanus berggreni Assemblage in Cores 909C-100R-2 to -91R-1 (1040.71-952.78mbsf); (2) a Reticulophragmium amplectens Assemblage in Cores 909C-87R-2, to -71R-3 (915.7-762.68mbsf); and (3) a low-diversity Reticulophraginium rotundidorsatum Assemblage in Cores 909C-71R-1 to -55R-1 (759.68-605.52mbsf). The DWAF assemblages are correlated to the standard chronostratigraphy using dinoflagellate cysts and magnetostratigraphy. The stratigraphic ranges of some well-known Palcogene DWAF species extend far into the Miocene at this locality, confirming tire hypothesis that the Arctic and northern Norwegian Sea basins served as a refuge for these species long after they disappeared from the North Atlantic stratigraphic record. The taxonomic affinities of the Miocene assemblages from Hole 909C supports the idea that an estuarine Circulation pattern has been in place between the Arctic Ocean and Greenland Sea basins since at least the early Miocene. Changes in the benthic foraminiferal morphogroups within the R. rotundidorsatum Assemblage correlate with an increase in total organic carbon, indicating an increase in oceanic productivity in the Fram Strait region during the late Miocene

Dynamics of chemosensitivity and chromosomal instability in recurrent glioblastoma

Glioblastoma multiforme is characterised by invasive growth and frequent recurrence. Here, we have analysed chromosomal changes in comparison to tumour cell aggressiveness and chemosensitivity of three cell lines established from a primary tumour and consecutive recurrences (BTL1 to BTL3) of a long-term surviving glioblastoma patient together with paraffin-embedded materials of five further cases with recurrent disease. Following surgery, the BTL patient progressed under irradiation/ lomustine but responded to temozolomide after re-operation to temozolomide. The primary tumour -derived BTL1 cells showed chromosomal imbalances typical of highly aggressive glioblastomas. Interestingly, BTL2 cells established from the first recurrence developed under therapy showed signs of enhanced chromosomal instability. In contrast, BTL3 cells from the second recurrence resembled a less aggressive subclone of the primary tumour. Although BTL2 cells exhibited a highly aggressive phenotype, BTL3 cells were characterised by reduced proliferative and migratory potential. Despite persistent methylation of the O6-methylguanine-DNA methyltransferase promoter, BTL3 cells exhibited the highest temozolomide sensitivity. A comparable situation was found in two out of five glioblastoma patients, both characterised by enhanced survival time, who also relapsed after surgery/chemotherapy with less aggressive recurrences. Taken together, our data suggest that pretreated glioblastoma patients may relapse with highly chemosensitive tumours confirming the feasibility of temozolomide treatment even in case of repeated recurrence

Dataset of calcareous nannoplankton and smaller benthic foraminifera from a nummulitic accumulation (Bartonian, Eocene, Transylvanian Basin, Romania)

Data reported herein, have been obtained from the micropaleontological analysis of the middle Eocene (Bartonian) calcareous nannoplankton and smaller benthic foraminifera record from nine representative areas located in the Gilău and Meseș area from the Transylvanian Basin, Romania. The micropaleontological data comprise raw species counts (Tables 1, 2), relative abundances (Tables 3, 4) and ARCSIN-normalized values used to perform multivariate analysis (Tables 5, 6) for both calcareous nannoplankton and smaller benthic foraminiferal assemblages. The ARCSIN-normalized datasets (Tables 5, 6) include only taxa with more than ~2% relative abundance (Table 5, calcareous nannoplankton) and only taxa having more than 1% relative abundance (Table 6, smaller benthic foraminfiera ). The calculated abundance data of smaller benthic foraminiferal taxa, groups and microhabitats, the calculated benthic foraminifera dissolved oxygen index – BFOI are presented in Table 7, whilst the diversity indices of smaller benthic foraminifera are included in Table 8. Same background color in each table represents the same outcrop and the samples are stored in case of each outcrop in stratigraphic order (samples with the same style – italic and bold – belong to the same stratigraphic level). In the case of the calcareous nannoplankton datasets (Tables 1, 3, 5) the samples written with red had less than 50 specimens and they were excluded from the statistical analysis

Dataset of calcareous nannoplankton and smaller benthic foraminifera from a nummulitic accumulation (Bartonian, Eocene, Transylvanian Basin, Romania)

Data reported herein, have been obtained from the micropaleontological analysis of the middle Eocene (Bartonian) calcareous nannoplankton and smaller benthic foraminifera record from nine representative areas located in the Gilău and Meseș area from the Transylvanian Basin, Romania. The micropaleontological data comprise raw species counts (Tables 1, 2), relative abundances (Tables 3, 4) and ARCSIN-normalized values used to perform multivariate analysis (Tables 5, 6) for both calcareous nannoplankton and smaller benthic foraminiferal assemblages. The ARCSIN-normalized datasets (Tables 5, 6) include only taxa with more than ~2% relative abundance (Table 5, calcareous nannoplankton) and only taxa having more than 1% relative abundance (Table 6, smaller benthic foraminfiera ). The calculated abundance data of smaller benthic foraminiferal taxa, groups and microhabitats, the calculated benthic foraminifera dissolved oxygen index – BFOI are presented in Table 7, whilst the diversity indices of smaller benthic foraminifera are included in Table 8. Same background color in each table represents the same outcrop and the samples are stored in case of each outcrop in stratigraphic order (samples with the same style – italic and bold – belong to the same stratigraphic level). In the case of the calcareous nannoplankton datasets (Tables 1, 3, 5) the samples written with red had less than 50 specimens and they were excluded from the statistical analysis

Dataset of calcareous nannoplankton and smaller benthic foraminifera from a nummulitic accumulation (Bartonian, Eocene, Transylvanian Basin, Romania)

Data reported herein, have been obtained from the micropaleontological analysis of the middle Eocene (Bartonian) calcareous nannoplankton and smaller benthic foraminifera record from nine representative areas located in the Gilău and Meseș area from the Transylvanian Basin, Romania. The micropaleontological data comprise raw species counts (Tables 1, 2), relative abundances (Tables 3, 4) and ARCSIN-normalized values used to perform multivariate analysis (Tables 5, 6) for both calcareous nannoplankton and smaller benthic foraminiferal assemblages. The ARCSIN-normalized datasets (Tables 5, 6) include only taxa with more than ~2% relative abundance (Table 5, calcareous nannoplankton) and only taxa having more than 1% relative abundance (Table 6, smaller benthic foraminfiera ). The calculated abundance data of smaller benthic foraminiferal taxa, groups and microhabitats, the calculated benthic foraminifera dissolved oxygen index – BFOI are presented in Table 7, whilst the diversity indices of smaller benthic foraminifera are included in Table 8. Same background color in each table represents the same outcrop and the samples are stored in case of each outcrop in stratigraphic order (samples with the same style – italic and bold – belong to the same stratigraphic level). In the case of the calcareous nannoplankton datasets (Tables 1, 3, 5) the samples written with red had less than 50 specimens and they were excluded from the statistical analysis

Miocene facies associations and sedimentary evolution of the Southern Transylvanian Basin (Romania): implications for hydrocarbon exploration

The Transylvanian Basin is a mature hydrocarbon province of Romania characterized by two petroleum systems: Mesozoic (thermogenic) and Miocene (biogenic). An extensive outcrop-based sedimentological and micropaleontological study correlated to seismic and well data discusses the elements of the Miocene petroleum system. The facies associations are indicative of alluvial, fandelta, shallow- and deep-marine settings. These are grouped into four different depositional systems (evaporite, mud-carbonate, sand-mud and sand-gravel). Their evolution in time and space shows large differences between various parts of the basin that have important consequences for exploration. The Transylvanian gas is formed by more than 99% methane of bacterial origin. This is sourced by low quality (<1% TOC) deep-marine shales. The shales contain Type II and Type III kerogen. The organic material is thermally immature. The best source rocks were deposited during major transgressions in the central-eastern parts of the basin. In general, reservoir quality is the best (porosity < 20%, permeability < 1 D) in the basin center, where reservoirs are deep-marine turbidite sandstones. Lower quality reservoirs are conglomerate-rich slope channels and various shallow-marine sandstones located near the basin margins. The seals are formed by shales that hold gas columns of up to 60 m. The most common structural traps are in 4-way dip closures related to salt-cored folds. Their timing is coeval with the late (post-Pannonian) exhumation of the basin and strongly linked to coeval salt tectonics. This requires a late charge and migration. The largest traps typically have multistory (up to 20) pay zones with a total of 100 BCF to 1 TCF reserves. Exploration to date has focused on structural traps, but most of the obvious structures have been drilled. It is argued that significant exploration potential lies in stratigraphic plays, including confined submarine fans, slope channels, detached lowstand prograding wedges, incised valleys, diapir flanks, salt-tectonics related unconformities and various sub-volcanic plays. Risks of the petroleum system elements associated to these plays in different areas of the basin are discussed. © 2009 Elsevier Ltd. All rights reserved