RECENT PUBLICATIONS ON FORAMINIFERA 2012 (2)
LUTERIAN MAGNETOSTRATIGRAPHIC CALIBRATION OF LARGER FORAMINIFERA ZONATION
In this paper, we present a chronostratigraphic calibration of the shallow benthic zones (SBZs) of larger foraminifera during Lutetian times based on new magnetostratigraphic data (Isuela section) and two new densely sampled biostratigraphic sections (Isuela and Gabardiella). These sections are located in the External Sierras (Southern Pyrenees) and represent an ideal location to avoid previous chronostratigraphic problems.
Highlights ► New chronostratigraphic calibration of the SBZ for Lutetian at the Southern Pyrenees ► Highly dense sampling of a continuous profile in shallow carbonate shelf environment ► SBZ 13/14 boundary is now located at 44.46 Ma, reaching the chron C20r ► The limit SBZ 14/15 has a boundary time span between 41.36 and 42.45 Ma ► The new boundary SBZ 15/16 can be accurately located at 41.12 Ma (C19r) (ABSTRACT)
Rodríguez-Pintó, A., Pueyo, E.L., Serra-Kiel, J., Samsó, J.M., Barnolas, A., Pocoví, A., in press. Lutetian magnetostratigraphic calibration of larger foraminifera zonation (SBZ) in the Southern Pyrenees: The Isuela Section. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.03.012
COMBINED EFFECTS OF ELEVATED TEMPERATURE AND DIURON ON SYMBIONT-BEARING FORAMINIFERA
Elevated ocean temperatures and agrochemical pollution individually threaten inshore coral reefs, but these pressures are likely to occur simultaneously. Experiments were conducted to evaluate the combined effects of elevated temperature and the photosystem II (PSII) inhibiting herbicide diuron on several types of symbiotic algae (diatom, dinoflagellate or rhodophyte) of benthic foraminifera in hospite. Diuron was shown to evoke a direct effect on photosynthetic efficiency (reduced effective PSII quantum yield ΔF/F′m), while elevated temperatures (>30°C, only 2°C above current average summer temperatures) were observed to impact photosynthesis more indirectly by causing reductions in maximum PSII quantum yield (Fv/Fm), interpreted as photodamage. Additionally, elevated temperatures were shown to cause bleaching through loss of chlorophyll a in foraminifera hosting either diatoms or dinoflagellates. A significant linear correlation was found between reduced Fv/Fm and loss of chlorophyll a. ......
van Dam, J.W., Negri, A.P., Mueller, J.F., Altenburger, R., Uthicke, S., 2012. Additive pressure of elevated sea surface temperatures and herbicides on symbiont-bearing foraminifera. PLoS ONE 7 (3): e33900. doi:10.1371/journal.pone.0033900
LARGE, ENIGMATIC FORAMINIFERAN-LIKE PROTISTS IN THE CLARION-CLIPPERTON FRACTURE ZONE
Komokiaceans and similar large (millimetre-sized to centimetre-sized) testate protists resembling Foraminifera are a ubiquitous and often dominant component of abyssal macrofaunal assemblages. Yet they are often overlooked and many forms are undescribed, often at the genus or higher taxon level. As a result, they represent a major source of unknown biodiversity in the deep sea. We studied the diversity and vertical distribution of these delicate, often fragmentary organisms in sediment samples (0- to 6-cm layer) collected from three sites in the eastern part of the Clarion-Clipperton polymetallic nodule field (subequatorial NE Pacific) during the 1997 cruise of the RV Professor Logachev organised by the Interoceanmetal Joint Organization (IOM). A total of 102 morphospecies and morphotypes was recorded (28-69 per station), indicating an extremely diverse assemblage. Although most were found in the uppermost 2 cm, deeper sediment layers also yielded some species. This is one of only a few studies of komokiaceans and related organisms in this part of the Pacific. It contributes to baseline knowledge of abyssal communities in an area targeted for future commercial nodule mining operations. (ABSTRACT)
Kamenskaya, O., Gooday, A.J., Radziejewska, T., Wawrzyniak-Wydrowska, B., in press. Large, enigmatic foraminiferan-like protists in the eastern part of the Clarion-Clipperton Fracture Zone (abyssal north-eastern subequatorial Pacific): biodiversity and vertical distribution in the sediment. Marine Biodiversity, doi:10.1007/s12526-012-0114-7
MERIDIONAL TEMPERATURE GRADIENT IN THE EASTERN NORTH ATLANTIC DURING MIS 11
Temporal and spatial patterns in eastern North Atlantic sea surface temperatures (SST) were reconstructed for marine isotope stage (MIS) 11c using a submeridional transect of five sediment cores. The SST reconstructions are based on planktic foraminiferal abundances and alkenone indices, and are supported by benthic and planktic stable isotope measurements, as well as by ice-rafted debris content in polar and middle latitudes. Additionally, the larger-scale dynamics of the precipitation regime over northern Africa and the western Mediterranean region was evaluated from iron concentrations in marine sediments off NW Africa and planktic δ13C in combination with analysis of planktic foraminiferal abundances down to the species level in the Mediterranean Sea. Compared to the modern situation, it is revealed that during entire MIS 11c sensu stricto (ss), i.e.,between 420 and 398 ka according to our age models, a cold SST anomaly in the Nordic seas co-existed with a warm SST anomaly in the middle latitudes and the subtropics, resulting in steeper meridional SST gradients than during the Holocene. Such a SST pattern correlates well with a prevalence of a negative mode of the modern North Atlantic Oscillation. We suggest that our sceanrio might partly explain the longer duration of wet conditions in the northern Africa during MIS 11c compared to the Holocene. (ABSTRACT)
Kandiano, E.S., Bauch, H.A., Fahl, K., Helmke, J.P., Röhl, U., Pérez-Folgado, M., Cacho, I., in press. The meridional temperature gradient in the eastern North Atlantic during MIS 11 and its link to the ocean–atmosphere system. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.03.005
HIGH RESOLUTION SSTMg/Ca RECORD FOR GLOBIGERINA BULLOIDES IN THE GULF OF LION
We generated a high-resolution SSTMg/Ca record for the surface-dwelling planktonic foraminifera Globigerina bulloides from the core MD99-2346 collected in the Gulf of Lion, and compared it to that obtained using modern analogue techniques applied to fossil foraminiferal assemblages (SSTMAT). The two temperature records display similar patterns during the last 28,000 years but the SSTMg/Ca estimates are several degrees warmer (∼ +4 °C) than SSTMAT. The temperature shift between SSTMg/Ca and SSTMAT remained relatively constant over time. This seems to exclude a bias on the Mg/Ca record associated with salinity or secondary Mg-rich calcite encrustation on the foraminiferal tests during early diagenesis. Therefore, anomalously high Mg/Ca suggests either: (1) the empirical equation for G. bulloides of Elderfield and Ganssen (2000) is incorrect; or (2) there is a specific Mediterranean genotypes of G. bulloides for which a specific Mg/Ca-temperature calibration is needed. (ABSTRACT)
Boussetta, S., Kallel, N., Bassinot, F., Labeyrie, L., Duplessy, J-C., Caillon, N., Dewilde, F., Rebaubier, H., in press. Mg/Ca-paleothermometry in the western Mediterranean Sea on planktonic foraminifer species Globigerina bulloides: Constraints and implications. Comptes Rendus Geoscience, doi:10.1016/j.crte.2012.02.001
MORPHOGROUPS AND SMALL SIZED TEST IN PSEUDOTEXTULARIA ELEGANS AS A PALEOENVIRONMENTAL STRESS INDICATOR
Cretaceous–Paleocene shelf successions of Therriaghat and Mahadeo in Meghalaya, India preserve almost the whole of the Late Maastrichtian stage, in which the warm water Tethyan planktonic foraminifera Pseudotextularia elegans (Rzehak) occurs in the Racemiguembelina fructicosa Zone (=Zone CF4) and Pseudoguembelina palpebra Zone (=Zone CF2) as five distinct morphogroups (A–E). ...... Diverse morphogroups and small tests are unique in the species of Meghalaya; however, the cause of such unusual growth is difficult to explain. Due to development close to the tectonically active Deccan volcanic Province and the Assam–Arakan and Himalayan mobile belts, the Meghalaya shelf had unusual biotic stress due to volcanic eruption, sea level fluctuations induced by plate collision and climate warming and retreat of the neo-Tethys. During the biozones CF4 and CF2 when vigorous Deccan outbursts occurred, P. elegans developed diverse morphogroups and acquired small size tests to cope with the changed environments and possibly to increase its chances of avoiding by microspherule missiles. (ABSTRACT)
Mukhopadhyay, S.K., 2012. Morphogroups and small sized tests in Pseudotextularia elegans (Rzehak) from the Late Maastrichtian succession of Meghalaya, India as indicators of biotic response to paleoenvironmental stress. Journal of Asian Earth Sciences 48, 112-124
PALAEOGEOGRAPHY AND RELATIVE SEA-LEVEL HISTORY IN LATE JURASSIC EPICONTINENTAL SHELVES
The analysis of macroinvertebrate and foraminiferal assemblages from Upper Jurassic (Middle Oxfordian to Lower Kimmeridgian) epicontinental shelf deposits in the Prebetic (Betic Cordillera, southern Spain) reveals the influence of environmental changes. They are expressed as selected parameters in palaeogeographic and stratigraphic trends (litho- and microfacies, faunal composition, taphonomy), which are interpreted in the context of relative sea-level histories. ...... An ecostratigraphic approach is used here to correlate and characterise sea-level changes, applying high resolution stratigraphy to sections where the identification of relevant surfaces is more difficult. The changes in distance from shore and ecospace, triggered by relative sea-level fluctuations, are considered prime factors forcing trade-offs in faunal communities of the studied fossil assemblages. Ecostratigraphy was used as a template for the characterization, correlation and interpretation of relative sea-levels and associated sedimentary packages in a time span from just above the Milankovitch band to the million-year scale. (ABSTRACT)
Olóriz, F., Reolid, M., Rodríguez-Tavor, F., in press. Palaeogeography and relative sea-level history forcing eco-sedimentary contexts in Late Jurassic epicontinental shelves (Prebetic Zone, Betic Cordillera): An ecostratigraphic approach. Earth-Science Reviews, doi:10.1016/j.earscirev.2011.11.004
THE OLIGOCENE MENILITE FORMATION, POLISH CARPATHIANS: A PROXY TO OXYGENATION HISTORY
The anoxic, mostly black or brown fine-grained sediments of the Menilite Formation (Oligocene–Early Miocene) in the Skole and Subsilesian nappes contain thin layers of bioturbated green or grey-green mudstones, some of which contain the trace fossils Halimedides annulata, Multina isp., Palaeophycus ?tubularis, ?Planolites isp., Rhizocorallium isp., Trichichnus isp. and Zoophycos isp. ...... The combination of ichnological and ichthyological data and incorporation of data on benthic foraminifers allowed a reconstruction of oxygenation changes in the sediment and water column during deposition of the Menilite Formation. Total anoxia at the sea floor and in the water column, attributed to a combination of thermo-stratification and extremely high organic productivity, occurred only during the period reflected by ichthyofaunal Zone IPM2 (middle part of the NP23 Zone). Anoxia restricted to the basin floor or upper slope, related in part to upwelling, occurred during sedimentation of the upper part of the Menilite Formation. (ABSTRACT)
Kotlarczyk, J., Uchman, A., in press. Integrated ichnology and ichthyology of the Oligocene Menilite Formation, Skole and Subsilesian nappes, Polish Carpathians: A proxy to oxygenation history. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.03.002
PALAEOECOLOGY OF THE OLIGOCENE–MIOCENE ASMARI FORMATION IN THE DILL ANTICLINE, IRAN
Dezful Embayment of the Zagros Basin was examined. The Asmari Formation was deposited in a subtropical environment in an oligophotic to euphotic zone. The setting was a carbonate ramp with oligotrophic to mesotrophic conditions as indicated by the association of large benthic foraminifera (Heterostegina, Spiroclypeus, Amphistegina, Neorotalia, Miogypsinoides, Borelis, Archaias, Peneroplis and Dendritina) with coral debris during Chattian to Early Aquitanian and Burdigalian times. The carbonate grain associations within the Asmari Formation indicate: 1. that the lower part of the Asmari Formation (Early Chattian) was deposited in normal saline waters (middle ramp), and 2. that the middle and upper parts of the Asmari Formation (Middle Chattian-Burdigalian) experienced higher to hyper-saline waters (semi-to restricted lagoon environments of inner ramp). The diversity of large benthic foraminifera, the rarity of coral debris and the absence of green algae in the Dill Anticline area indicate a minimum surface water temperature of < 20 °C. ...... (ABSTRACT)
Dill, M.A., Seyrafian, A., Vaziri-Moghaddam, H., 2012. Palaeoecology of the Oligocene-Miocene Asmari Formation in the Dill Anticline (Zagros Basin, Iran). Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 263 (2), 167-184.
BIOSTRATIGRAPHY OF THE OLIGOCENE-MIOCENE ASMARI FORMATION, SW IRAN
Paleontological and biostratigraphical studies on a carbonate platform succession from southwestern Iran documented a high diversity of shallow-water benthic foraminifera during the Oligocene-Miocene. Larger foraminifera are the main means for stratigraphic zonation of the Asmari Formation. The distributions of larger benthic foraminifera in two outcrop sections (Khaviz and Bangestan Anticlines) in the central part of the Zagros Fold-and-Thrust Belt (Iran) are used to determine the age of the Asmari Formation in this area. Four assemblage zones are recognized by distribution of larger benthic foraminifera in the study areas. ...... (ABSTRACT)
Rahmani, A., Taheri, A., Vaziri-Moghaddam, H., Ghabeishavi, A., 2012. Biostratigraphy of the Asmari Formation at Khaviz and Bangestan Anticlines, Zagros Basin, SW Iran. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 263 (1), 1-16.
HYBRIDIZATION OF MORPHOLOGICALLY DIFFERENT POPULATIONS OF PATAGONIAN ELPHIDIUM
Elphidium macellum is a benthic foraminifer commonly found in the Patagonian fjords. To test whether its highly variable morphotypes are ecophenotypes or different genotypes, we analysed 70 sequences of the SSU rRNA gene from 25 specimens. Unexpectedly, we identified 11 distinct ribotypes, with up to 5 ribotypes co-occurring within the same specimen. The ribotypes differ by varying blocks of sequence located at the end of stem-loop motifs in the three expansion segments specific to foraminifera. These changes, distinct from typical SNPs and indels, directly affect the structure of the expansion segments. Their mosaic distribution suggests that ribotypes originated by recombination of two or more clusters of ribosomal genes. We propose that this expansion segment polymorphism (ESP) could originate from hybridization of morphologically different populations of Patagonian Elphidium. We speculate that the complex geological history of Patagonia enhanced divergence of coastal foraminiferal species and contributed to increasing genetic and morphological variation.
Pillet, L., Fontaine, D., Pawlowski, J., 2012. Intra-Genomic Ribosomal RNA Polymorphism and Morphological Variation in Elphidium macellum Suggests Inter-Specific Hybridization in Foraminifera. PLoS ONE 7 (2): e32373. doi:10.1371/journal.pone.0032373
BIOGEOGRAPHY AND ECOSTRATIGRAPHY OF LATE QUATERNARY PLANKTONIC FORAMINIFERAL TAPHOCOENOSES
The Leeward Islands lie within an oceanographically complex area influenced by North Atlantic Gyre flow and the Orinoco plume. Late Quaternary planktonic foraminiferal assemblages are reported from three middle bathyal piston cores (from NW to SE: En20-2, En20-10, En20-16) in the Leeward Islands. En20-2 was obtained closest to the 200 m bathymetric contour, En20-10 farthest offshore. The bathyal benthonic foraminifera from En20-2 are indicative of high surface productivity. The planktonic foraminiferal assemblages differ between the cores. ...... Bottom-up SHE Analysis for Biozone Identification (SHEBI) indicates that each core contains several abundance biozones (ABs), but these do not correlate between the cores. Alpha diversities were SE = 8.3–14.3 effective species, while beta diversities ranged from 0.65 to 1.54, but only two were statistically significant. Complementarities (64.7–87.6%) indicate that the AB boundaries reflect changes in the relative abundances of species, not overall diversity.
Highlights ► Bathyal benthonic foraminifera in the Leeward Islands reflect fluctuations in surface productivity. ► Planktonic foraminifera show similar small-scale (< 150 km) changes in assemblages. ► Assemblages changed independently at the three sites examined. ► There was no change in diversity at the Pleistocene\Holocene boundary. ► Globigerinoides ruber is most abundant offshore, close to the Anegada Passage. (ABSTRACT)
Wilson, B., 2012. Biogeography and ecostratigraphy of Late Quaternary planktonic foraminiferal taphocoenoses in the Leeward Islands, Lesser Antilles, NE Caribbean Sea. Marine Micropaleontology, 86-87, 1-10.
PALEOCEANOGRAPHY OF THE LAST 500 krys IN THE OKHOTSK SEA BASED ON GEOCHEMISTRY
Analyses of geochemical constituents (organic carbon, nitrogen, calcium carbonate, and biogenic opal) on Core YK07-12 PC3B (Core PC3B) provided detailed and useful information in biological productivity and paleoceanographic changes, which occurred in the central Okhotsk Sea during the last 500 kyrs. An age model for Core PC3B was established based on changes in benthic foraminiferal δ18O. The trend in organic carbon (OC) content represented the temporal change that can be correlated with the δ18O curve in Core PC3B: high during the interglacial periods: MIS 1, 5, 9, 11, and 13. The trend in CaCO3 content represented is similar to the trend seen in the OC content. The high correlation between OC and CaCO3 contents indicates an increase in coccolithophorid productivity during the early deglaciations. The comparison between the changes in CaCO3 and biogenic opal indicates that the dominant phytoplankton group was coccolithophorids during the early deglaciations, which was subsequently replaced by diatoms during the late deglaciations. It appears that such a temporal phytoplankton succession was caused by an increase in dissolved silicon supply to the euphotic layer, possibly associated with a change in surface hydrography that subsequently caused an upward expansion of the intermediate layer. Such ecological changes probably played an important role in the uptake of atmospheric CO2. (ABSTRACT)
Iwasaki, S., Takahashi, K., Maesawa, T., Sakamoto, T., Sakai, S., Iijima, K., in press. Paleoceanography of the last 500 kyrs in the central Okhotsk Sea based on geochemistry. Deep Sea Research II, 10.1016/j.dsr2.2011.03.003
SST FOR LEFT-COILING NEOGLOBOQUADRINA POPULATION IN THE MIDDL PLEISTOCENE AND THE PLEISTOCENE-PLIOCENE TRANSITION
Using the modern analog methodology applied to planktonic foraminifers, we analyze the relation between the frequency of the coiling type in Neogloboquadrina populations and the sea-surface temperatures (SST) during the middle Pleistocene and the Pleistocene-Pliocene transition in the Alboran Sea (westernmost Mediterranean), close to the Atlantic connection. The results reveal that the present-day positive correlation between the two variables (r = 0.649) is maintained even with a higher coefficient (r = 0.783) in the middle Pleistocene but falls slightly (r = 0.517) in the Pleistocene-Pliocene transition due mainly to a dispersal of the temperatures for the samples bearing predominantly left-coiling Neogloboquadrina. ...... (ABSTRACT)
Serrano, F., Guerra-Merchán, A., in press. Sea-surface temperature for left-coiling Neogloboquadrina populations inhabiting the westernmost Mediterranean in the middle Pleistocene and the Pleistocene-Pliocene transition. Geobios, doi:10.1016/j.geobios.2011.04.003
UPPER JURASSIC-LOWER CRETACEOUS CARBONATE PLATFORM FROM THE VALCAN MOUNTAINS
The results of a biostratigraphic and sedimentological study of the Upper Jurassic–Lower Cretaceous limestones cropping out in the southern sector of the Vâlcan Mountains in Romania are presented, including the definition of microfacies types, fossil assemblages and environmental interpretation. Six microfacies types (MFT 1–MFT 6) have been identified, each of them pointing to a specific depositional environment. The deposits are characteristic of a shallow carbonate platform. They contain normal marine or restricted marine facies deposited in low or high energy environments from the inner, middle and outer platform. The age attribution of these deposits (Late Jurassic to Berriasian–Valanginian–?Hauterivian, and Barremian) is based on foraminiferal and calcareous algae associations. The micropaleontological assemblage is exceptionally rich in the Vâlcan Mountains and brings new arguments for dating the Upper Jurassic–Lower Cretaceous limestones in this area. (ABSTRACT)
Michetiuc, M., Catincut, C., Bucur, I.I., 2012. An Upper Jurassic–Lower Cretaceous carbonate platform from the Valcan Mountains (Southern Carpathians, Romania): paleoenvironmental interpretation. Geologica Carpathica 63 (1), 33-48.
MIOCENE-PLIOCENE PALAEOBATHYMETRIC GRADIENTS ACROSS TIMOR
Palaeobathymetry is interpreted for the oldest post-collision deposits present in Timor. The distributions of planktonic and benthic foraminifera in chalk, marl and mudstone successions that accumulated during 5.7–3.3 Ma form the bases for age zonation and water-depth interpretation. Data from 77 samples collected from 11 stratigraphic sections in East Timor are combined with information previously published from several sections in West Timor to provide control points for palaeobathymetric contouring. The bathymetric reconstruction is based on interpreted water depths at the control points in combination with aspects of the spatial geology of Timor. ......
Highlights ► Topography of Timor orogenic pile at 5.7–3.3 Ma is interpreted. ► Planktonic foraminifera date oldest synorogenic deposits at 5.7–5.5 Ma. ► Bathymetry for time zones N18, N19r, N20r is interpreted from benthic foraminifera. ► Contours suggest deepening toward south where 1500–2500 m deep basin developed. ► Little topographic change took place from 5.7–3.3 Ma. (ABSTRACT)
Haig, D.W., in press. Palaeobathymetric gradients across Timor during 5.7–3.3 Ma (latest Miocene – Pliocene) and implications for collision uplift. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.02.032
EARLY EOCENE HYPERTHERMALS AND ASSOCIATED OCEANOGRAPHIC CHANGES
Within the last decade, several early Eocene hyperthermals have been detected globally. These transient warming events have mainly been characterized geochemically - using stable isotopes, carbonate content measurements or XRF core scanning - yet detailed micropaleontological records are sparse, limiting our understanding of the driving forces behind hyperthermals and of the contemporaneous paleoceanography. Here, detailed geochemical and quantitative benthic foraminiferal records are presented from lower Eocene pelagic sediments of Deep Sea Drilling Project Site 401 (Bay of Biscay, northeast Atlantic). In calcareous nannofossil zone NP11, several clay-enriched levels correspond to negative δ13C and δ18O bulk-rock excursions with amplitudes of up to ~ 0.75‰, suggesting that significant injections of 12C-enriched greenhouse gases and small temperature rises took place. ......
Highlights ► We investigate early Eocene deep-sea deposits in the North Atlantic. ► Negative carbon and oxygen isotope excursions occur within five marly levels. ► A quantitative benthic foraminiferal study reveals associated oceanographic changes. ► Changes are related to hyperthermal events. ► These hyperthermals are expressed in a similar way as the PETM. (ABSTRACT)
D'haenens, S., Bornemann, A., Stassen, P., Speijer, R.P., in press. Multiple early Eocene benthic foraminiferal assemblage and δ13C fluctuations at DSDP Site 401 (Bay of Biscay – NE Atlantic). Marine Micropaleontology, doi:10.1016/j.marmicro.2012.02.006
A NEW GENUS OF INVOLUTININA AND ITS MORPHOLOGICAL, BIOSTRATIGRAPHIC AND EVOLUTIONARY SIGNIFICANCE
The Late Triassic was a time of pronounced radiation in several groups of foraminifers. Among others the rapid evolutionary processes in the Suborder Involutinina caused particularly high diversification of these aragonitic foraminifers, which became a key group for Upper Triassic biostratigraphy. Among them, Triasina hantkeni and Triasina oberhauseri are regarded as the most precise guide fossils. However, while these species are widely used, a poor documentation of the detailed test structure of T. oberhauseri has resulted in misidentifications. The exceptional preservation and abundance of Triasina oberhauseri in the Upper Triassic deposits of the Black Marble Quarry (Wallowa terrane, Oregon, USA) has allowed us to make the first detailed observations of its coiling, innermost structure and lamellae arrangement. ...... (ABSTRACT)
Rigaud, S., Martini, R., Rettori, R., in press. A new genus of Norian involutinid foraminifer: Its morphological, biostratigraphic and evolutionary significance. Acta Palaeontologica Polonica, doi:10.4202/app.2011.0072
BIODIVERSITY AND COMMUNITY STRUCTURE OF LATE PLEISTOCENE FORAMINIFERA
The raised coral reef sequences at Kish Island provide a rare window into the depositional setting and paleoenvironment of a high-latitude, shallow-water coral reef that developed under turbid conditions in the Persian Gulf during Marine Isotope Stage 7 (~200 to 250 ka). Six sedimentary facies and eight foraminiferal assemblages can be identified throughout the sequence. A ninth assemblage can be defined for the modern subtidal realm. ...... Like the modern Persian Gulf, the diversity of foraminifera was low (~80 common species) during the Pleistocene and does not correlate with foraminiferal abundance. (ABSTRACT)
Mossadegh, Z.K., Paerker, J., Gischler, E., in press. Biodiversity and community structure of Late Pleistocene foraminifera from Kish Island, Persian Gulf (Iran). Facies, doi:10.1007/s10347-011-0286-9
ECOLOGY OF JURASSIC-CRETACEOUS Mohlerina basiliensis
Mohlerina basiliensis (Mohler, 1938) represents a common, cosmopolitan, shallow-water Middle Jurassic–Early Cretaceous trochospiral foraminifer. Given the numerous illustrations from thin-section specimens in the literature displaying tests dispersed within the matrix (micritic and sparitic), a free, vagile benthic mode of life is generally suggested. As an exceptional case, specimens are found with their tests attached to a variety of hard substrates, thus creating a special elevated microhabitat. The fixation is due to a calcitic cement. With its facultative sessile mode of life, Mohlerina can be compared with several modern calcareous trochospiral rotaliacean foraminifera (e.g., Ammonia, Cibicides, Discorbis). The rare preservation of fixed Mohlerina in situ is most likely due to physical taphonomic degradation (e.g., breakage). Tests of Mohlerina attached to hard substrates were found in both low- and high-energy paleoenvironments. The high test variability of Mohlerina might be influenced by the different settling strategies and substrate surface topographies within different paleohabitats. (ABSTRACT)
Schlagintweit, F., in press. Mohlerina basiliensis (Mohler, 1938): a Middle Jurassic–Early Cretaceous facultative (?) epilithic benthic foraminifer. Facies, doi:10.1007/s10347-012-0297-1
VARIABILITY IN PLANKTIC FORAMINIFERAL TEST FLUX IN THE BAY OF BISCAY
Test fluxes of planktic foraminifera in the Bay of Biscay were sampled in spring using drifting sediment traps deployed at 200 m depth. At a temporal and spatial resolution of three hours and approximately 1 km the foraminifer flux varied with a factor of 5. The consecutive deployments within the same area, at distances of ~50 km differed significantly in flux and relative species abundances. Flux sequences of the total foraminifer assemblage and individual species were significantly autocorrelated. The significance of autocorrelation analyses was affected by sample size of the flux sequences and limited to flux sequences with large fluxes. Autocorrelation in planktic foraminifer fluxes and standing stocks was restricted to distances <2 km, and were not attributed to the temporal domain. (ABSTRACT)
Siccha, M., Schiebel, R., Schmidt, S., Howa, H., in press. Short-term and small-scale variability in planktic foraminifera test flux in the Bay of Biscay. Deep Sea Research I, doi:10.1016/j.dsr.2012.02.004
METHODS IN RECENT BENTHIC FORAMINIFERAL STUDIES
Benthic foraminifera have proven to be suitable for environmental monitoring because of their high levels of adaptation, small size and high abundance in Recent sediments and the fossil record. Foraminifera are scarcely used in monitoring studies because a standardization of methods has not been achieved to date. When particular methods were introduced and why they were applied is often hidden in the literature. This paper reviews the development of field and laboratory methods, their constraints and consequences for faunal and data analyses. ...... (ABSTRACT)
Schönfeld, J., 2012. History and development of methods in Recent benthic foraminiferal studies. Journal of Micropalaeontology 31 (1), 53--72.
OUTER NERITIC ASSEMBLAGES IN THE AFTERMATH OF THE PETM
Deep-sea benthic foraminiferal faunas underwent severe extinction during the Paleocene–Eocene thermal maximum (PETM), but less is known about neritic environments. Through taxonomical analysis we document for the first time that recovery of neritic benthic assemblages after the PETM followed a similar pattern in shelf regions in New Jersey (USA) and Egypt. (ABSTRACT)
Stassen, P., Thomas, E., Speijer, R.P., 2012. Restructuring outer neritic foraminiferal assemblages in the aftermath of the Paleocene–Eocene thermal maximum. Journal of Micropalaeontology 31 (1), 89--93.
BIODIVERSITY OF FORAMINIFERA BETWEEN MIS 5 AND THE HOLOCENE IN THE RED SEA
Tropical coral reefs are among the most diverse marine ecosystems. In order to better understand temporal and spatial variation in late Quaternary biodiversity, foraminiferal faunas of two fossil, raised reef terraces at the southern Sinai Peninsula were studied and compared to modern coral reef faunas. Eleven U-series dates of shell fragments of the giant clam Tridacna sp. indicates deposition largely during marine isotope stage 5 (MIS 5), 77–129 kyrs BP, for the two raised terraces.
Highlights ► Community structure of coral-reef foraminifera has changed between MIS 5 and the Holocene ► Diversity of coral-reef foraminifera was higher during MIS 5 than during the Holocene ► Inner-neritic environments of the Red Sea during MIS 5 were closer to normal marine than today (ABSTRACT)
Parker, J.H., Gischler, E., Eisenhauer, A., in press. Biodiversity of foraminifera from Late Pleistocene to Holocene coral reefs, South Sinai, Egypt. Marine Micropaleontology, doi:10.1016/j.marmicro.2012.02.002
TESTING FORAMINIFERAL DISTRIBUTIONS AS TOOLS FOR BIOMONITORING ESTUARINE POLLUTION
Biomonitoring of estuarine pollution is the subject of active research, and benthic foraminifera are an attractive group to use for these purposes due to their ubiquitous presence in saline water and wide diversity. Here, we describe a case study of biomonitoring using benthic foraminifera in the French Mediterranean lagoon, Bages-Sigean lagoon. In this case, the major pollutants of interest are heavy metals in the sediment, particularly contaminated by Cu and Cd derived from industrial and agricultural sources. The foraminiferal assemblages of the Bages-Sigean lagoon are typical of normal paralic environments, but unusually almost completely lack agglutinated forms. The density of benthic foraminifera was shown to be more influenced by the sediment characteristics rather than heavy metal pollution. However, the relative abundance of Quinqueloculina bicostata was shown to increase in the most polluted areas and we propose that this taxon may be used as an indicator of heavy metal pollution.
Foster, W.J., Armynot du Châtelet, E., Rogerson, M., in press. Testing benthic foraminiferal distributions as a contemporary quantitative approach to biomonitoring estuarine heavy metal pollution. Marine Polution Bulletin, doi:10.1016/j.marpolbul.2012.01.021
FAUNAL-GEOCHEMICHAL INTERACTIONS – LIVING DEEP-SEA BENTHIC FORAMINIFERA
Rose-Bengal-stained benthic foraminifera were sampled along a depth transect from the Cap de Creus Canyon and the adjacent slope. Well-stained individuals were studied in the top 5 cm of sediment and the faunal abundances and assemblages were compared against pore-water geochemistry and biochemical composition of the sediment. Total standing stocks (TSS) of foraminifera were positively correlated with the chloroplastic pigment equivalents inventory (CPEinv; here interpreted as food quantity) and the ratio of chlorophyll-a and phaeopigment inventories (Chl-ainv/Phaeoinv; here interpreted as food quality), suggesting food quality as well as quantity play an important role in structuring the foraminiferal community. Food quality and food quantity were also identified by detrended correspondence analyses (DCA) as being the most important environmental parameters shaping the foraminiferal community structure (abundance and faunal composition). ...... The similarity between the deeper canyon and slope faunas suggests that sediment characteristics and the associated organic-matter transported by SWC and DSWC do not have a permanent effect at these depths. (ABSTRACT)
Contreras-Rosales, L.A., Koho, K.A., Duijnstee, I.A.P., de Stigter, H.C., Gracía-Novoa, R., Koning, E., Epping, E., in press. Living Deep-Sea Benthic Foraminifera From The Cap De Creus Canyon (Western Mediterranean): Faunal-Geochemical Interactions. Deep Sea Research Part I, doi:10.1016/j.dsr.2012.01.010,
TOARCIAN ANOXIC EVENTS IN THE WESTERN SAHARAN ATLAS (ALGERIA)
The present contribution constitutes the first morphogroup analysis of foraminiferal assemblages applied to the Toarcian Oceanic Anoxic Event (T-OAE) in the Maghreb region, which represented the northern palaeomargin of Gondwana. The ecostratigraphic and palaeoecologic analysis of the foraminiferal assemblages has allowed interpretation of the evolution of the biotic crisis associated with the T-OAE in the Saharan Atlas deposits and the recovery of foraminiferal assemblages in the sea-bottom after the event. ......
Highlights ► Toarcian Oceanic Anoxic Event in the Ksour Mountains characterised by azoic interval. ► Earliest Toarcian shows unstabilization with proliferation of opportunists. ► Decreasing oxygenation degree favoured stress-tolerant species. ► Dysoxia/anoxia at lower Levisoni Zone exceeded ecological threshold of opportunist. ► Recovery of foraminifera after anoxic event mainly by r-type strategists. (ABSTRACT)
Reolid, M., Sebane, A., Rodríguez-Tovar, F.J., Marok, A., in press. Foraminiferal morphogroups as a tool to approach the toarcian anoxic event in the Western Saharan Atlas (Algeria). Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.01.034
FACIES DEVELOPMENT ALONG THE TIDE-INFLUENCED SHELF OF THE BURDIGALIAN SEAWAY
Herein, we report quantitative micropaleontological (benthic foraminifers, dinoflagellate cysts, calcareous nannoplankton), sedimentological (grain-size analysis) and geophysical (background gamma radiation) analyses from Ottnang–Schanze, the stratotype for the regional Ottnangian stage (Central Paratethys; Lower Miocene, middle Burdigalian). The revealed trends in bathymetry, primary productivity, bottom-water oxygenation and water energy allow exemplary insights into the paleoenvironment of the terminal Burdigalian Seaway. Several facies of a eutrophic environment are distinguished that reflect a transition from a suboxic outer neritic to upper bathyal towards a better oxygenated middle neritic setting under the influence of storm events and currents. ......
Highlights ► We present a detailed facies analysis of the Ottnangian stratotype. ► Microfossil and lithological data indicate a eutrophic environment. ► A shallowing water depth resulted in increasing water-energy and oxygenation. ► The revealed trends reflect the final regressive phase of the Burdigalian Seaway. ► The beginning of the regression can be dated to c. 18 Ma. (ABSTRACT)
Grunert, P., Soliman, A., Ćorić, S., Roetzel, R., Harzhauser, M., Piller, W.E., 2012. Facies development along the tide-influenced shelf of the Burdigalian Seaway: An example from the Ottnangian stratotype (Early Miocene, middle Burdigalian). Marine Micropaleontology 84-85, 14--36.
SENSITIVITY OF PLANKTIC FORAMINIFERA TO MID-PLEISTOCENE CLIMATE CHANGE
The last one million years are important in terms of climate development during the so-called Mid-Pleistocene Transition when amplification of the glacial–interglacial cycles occurred. This study describes abundance changes in fossil planktonic foraminifera in sediments from Core T89-40, retrieved from the Walvis Ridge in the south-east Atlantic, across this time period. Cycles between upwelling and subtropical planktonic foraminiferal assemblages are shown to mirror changes between glacial and interglacial periods, respectively. During interglacial marine isotopic stages (MIS) 9, 11 and 31, however, anomalously high abundances of the polar left-coiled Neogloboquadrina pachyderma occur, presumably linked to unusual seasonal upwelling waters. The planktonic foraminiferal abundance record shows 41-ky cyclic variations in the regional oceanography linked to cycles in insolation influenced by changes in the Earth’s axial tilt (obliquity). These orbitally induced oscillations in oceanographic change occurred throughout the entire record. The most conspicuous feature of the planktonic foraminiferal record is the near absence of left-coiled Globorotalia truncatulinoides between 960 and 610 ka (MIS 26-15). The abrupt disappearance of this species is synchronous with the onset of the Mid-Pleistocene Transition in MIS 26. (ABSTRACT)
Ufkes, E., Kroon, D., 2012. Sensitivity of south-east Atlantic planktonic foraminifera to mid-Pleistocene climate change. Palaeontology 55 (1), 183--204.
NUMMULITIC BANKS IN THE UPPER LUTETIAN 'BUIL LEVEL': THE IMPACT OF INTERNAL WAVES
Nummulites, a particularly abundant and diverse genus of larger benthonic foraminifera, formed huge accumulations (banks) during the Eocene, which are often good hydrocarbon reservoirs, especially in North Africa. Despite their economical interest, these accumulations are not well-understood and their origin is still under discussion. Reasons for this debate are the absence of living Nummulites accumulations and the high-variability of facies, including the size, shape and extension of the banks, which reflect the array of processes controlling sediment production and accumulation. The nummulitic banks near Santa María de Buil, in the Ainsa Basin (South Pyrenean Foreland Basin) are composed of recurrent facies associations within mappable bed units bounded by physical surfaces. The depositional processes that produced the Nummulites deshayesi accumulations are interpreted considering the shape of the banks, the type of bounding surfaces, the distribution of sedimentary textures, Nummulites test shapes and the associated skeletal components within the banks. This integrative analysis indicates that nummulitic banks accumulated from mass flows, with very poor sediment sorting. Textural and compositional differences among banks suggest that globose Nummulites thrived in the shallower part of the mesophotic zone with abundant nummulithoclasts, whereas flat nummulitic forms thrived in deeper mesophotic, clay-dominated settings. ...... (ABSTRACT)
Mateu-Cicens, G., Pomar, L., Ferràdez-Cañadell, C., 2012. Nummulitic banks in the upper Lutetian ‘Buil level’, Ainsa Basin, South Central Pyrenean Zone: the impact of internal waves. Sedimentology 59 (2), 527--552.