RECENT PUBLICATIONS ON FORAMINIFERA 2012 (6)

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RECENT PUBLICATIONS ON FORAMINIFERA | 2013 (1) | 2012 (6) | 2012 (5) | 2012 (4) | 2012 (3) | 2012 (2) | 2012 (1) | 2011 (5) | 2011 (4) | 2011 (3) | 2011 (2) | 2011 (1) | 2010

POTENTIAL OF Fe-Mn COATINGS LEACHED FROM TESTS TO RECONSTRACT THE Nd ISOTOPE COMPOSITION OF SEAWATER

The Fe–Mn oxide fraction leached from deep-sea sediments has been increasingly used to reconstruct the Nd isotope composition of deep water masses, that can be used to track changes in oceanic circulation with a high temporal resolution. Application of this archive to reconstruct the Nd isotope composition of bottom seawater in shallow shelf environments remained however to be tested. Yet as the Nd isotope composition of seawater on continental margins is particularly sensitive to changes in erosional inputs, establishment of neritic seawater Nd isotope evolution around areas of deep water formation would be useful to discriminate the influence of changes in oceanic circulation and in isotopic composition of erosional inputs on the Nd isotope record of deep waters. The purpose of this study is to test the potential of Fe–Mn coatings leached from foraminifera tests to reconstruct the Nd isotope composition of seawater in shelf environments for deep-time intervals. ...... (ABSTRACT)


Charbonnier, G., Pucéat, E., Bayon, G., Desmares, D., Dera, G., Durlet, C., Deconinck, J.-F., Amédro, F., Gourlan, A.T., Pellenard, P., Bomou, B., 2012. Reconstruction of the Nd isotope composition of seawater on epicontinental seas: Testing the potential of Fe–Mn oxyhydroxide coatings on foraminifera tests for deep-time investigations. Geochimica et Cosmochimica Acta 99, 39-56.


OVER 100 YRS OF ENVIRONMENTAL CHANGE RECORDED BY FORAMINIFERS AND SEDIMENTS IN MOBILE BAY, GULF OF MEXICO

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The marine microfauna of Mobile Bay has been profoundly influenced by the development and expansion of the primary shipping channel over the last ∼100 years. Foraminifers and sediments from seven box cores with excess lead-210 chronology document that channel dredging and spoil disposal have altered circulation, reduced estuarine mixing, changed sedimentation patterns, and caused a faunal turnover within the bay. ...... Comparisons of the present-day foraminiferal assemblage with foraminifers collected in the early 1970s indicate that the continued biologic loss of calcareous foraminifers in the bay has allowed the introduction of a new agglutinated foraminiferal species into the bay. (ABSTRACT)


Osterman, L.E., Smith, C.G., 2012. Over 100 years of environmental change recorded by foraminifers and sediments in Mobile Bay, Alabama, Gulf of Mexico, USA. Estuarine, Coastal and Shelf Science 115, 345-358.


EUSTATIC SEA-LEVEL CONTROLS ON A FOREBULGE SETTING IN THE CRETACEOUS CANADIAN WESTERN INTERIOR SEA

The forebulge region of the Cretaceous Canadian Western Interior Sea (CWIS) was susceptible to subaerial exposure and marine erosion during sea level lowstands. The middle Albian to Santonian record as cored at Cold Lake, east-central Alberta, Canada documents numerous disconformities that are expressed in bioclastic concentration horizons and faunal extinctions and turnovers. Detailed comparison between a newly established δ13Corg. record measured on bulk sediment at Cold Lake and a combined δ13Ccarb. reference curve based on the Cretaceous English chalk and SE France hemipelagic marlstones highlights missing positive and negative δ13C excursions at the CWIS forebulge and thus missing sections that precisely corroborate with sequence boundaries. ...... (ABSTRACT)


Schröder-Adams, C.J., Herrle, J.O., Tu, Q., 2012. Albian to Santonian carbon isotope excursions and faunal extinctions in the Canadian Western Interior Sea: Recognition of eustatic sea-level controls on a forebulge setting. Sedimentary Geology 281, 50-58.


RECONSTRUCTING DEGLACIAL N AND S ATLANTIC DEEP WATER SOURCING USING FORAMINIFERAL Nd ISOTOPES

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During the last few decades, neodymium isotopes have been increasingly used as a paleoceanographic and paleoclimate proxy on million-year through millennial time-scales. The widespread use of the Nd isotope proxy depends on whether the Nd isotopic composition of past seawater can be reliably extracted from authigenic sediment phases. Here we show evidence that planktonic foraminifera with authigenic coatings preserve a deep water Nd isotopic signature and thus can be used to reconstruct past deep water Nd isotopes. ...... (ABSTRACT)


Piotrowski, A.M., Galy, A., Nicholl, J.A.L., Roberts, N., Wilson, D.J., Clegg, J.A., Yu, J., 2012. Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes. Earth and Planetary Science Letters 357-358, 289-297.


WITHIN- AND AMONG-GENUS COMPONENTS OF SIZE EVOLUTION DURING MASS EXTINCTION, RECOVERY AND BACKGROUND INTERVALS

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One of the best-recognized patterns in the evolution of organismal size is the tendency for mean and maximum size within a clade to decrease following a major extinction event and to increase during the subsequent recovery interval. Because larger organisms are typically thought to be at higher extinction risk than their smaller relatives, it has commonly been assumed that size reduction mostly reflects the selective extinction of larger species. However, to our knowledge the relative importance of within- and among-lineage processes in driving overall trends in body size has never been compared quantitatively. In this study, we use a global, specimen-level database of foraminifera to study size evolution from the Late Permian through Late Triassic. We explicitly decompose size evolution into within- and among-genus components. ...... (ABSTRACT)


Rego, B.L., Wang, S.C., Altiner, D., Payne, J.L., 2012. Within- and among-genus components of size evolution during mass extinction, recovery, and background intervals: a case study of Late Permian through Late Triassic foraminifera. Paleobiology 38 (4), 627-643.


SAMPLING BIAS AND THE FOSSIL RECORD OF PLANKTONIC FORAMINIFERA ON LAND AND IN THE DEEP SEA

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Large-scale trends in planktonic foraminiferal diversity have so far been based on utilization of synoptic biostratigraphic range charts. Although this approach ensures the taxonomic consistency and quality of the data being used, it takes no formal account of any sampling biases that might exist in the fossil record. We demonstrate that the occurrence data of planktonic foraminifera, as recorded in the primary literature, are strongly biased by sampling. We do this by demonstrating that raw diversity curves derived from the land-based and deep-sea records are strikingly different, but that they each correlate with the intensity of sampling in their respective environments, and thus are ultimately controlled by the structure of the geological record in each setting. ...... (ABSTRACT)


Lloyd, G.T., Pearson, P.N., Young, J.R., Smith, A.B., 2012. Sampling bias and the fossil record of planktonic foraminifera on land and in the deep sea. Paleobiology 38 (4), 569-584.


MIDDLE MIOCENE Amphistegina FROM OLIMPÓW, POLAND

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Specimens of Middle Miocene (Early Badenian) Amphistegina from the Polish Carpathians were examined. A section, sampled at the Olimpów quarry, displays chloralgal carbonates, rich in rhodolith nodules. Symbiont-bearing foraminifera (Amphistegina, Elphidium and Asterigerinata) constitute 15–57% of the total foraminifera assemblage. Amphistegina hauerina d’Orbigny, 1846 is the only species of the genus in the deposits studied.
The sensitivity of larger foraminifera to water turbulence and light availability was applied in a reconstruction of the community habitat. The diameter and thickness of the Amphistegina tests indicate that the habitat was a zone of low light penetration and weak energy – a palaeoenvironment, similar to that of the modern A. radiata (Hottinger et al., 1993). ...... (ABSTRACT)


Gonera, M., 2012. Middle Miocene (Early Badenian) Amphistegina (Foraminiferida) from Olimpów (Central Paratethys, Poland). ASGP 82, 151-159.


ARE THE LATE TRIASIC-EARLY JURASS OBERHAUSERELLIDAE THE ANCESTORS OF PLANKTONIC FORAMINIFERA?

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The attempt was made to prove if the Oberhauserellidae (Robertinina) are the ancestors of the planktonic foraminifera. The Robertinina described here (Oberhauserellidae and Reinholdeinae) are from strata of late Rhaetian to early Hettangian age of the Northern Calcareous Alps. Specimens are especially well preserved with their original aragonitic tests and these are compared here with similarly preserved Reinholdella and in all probability planktonic Conoglobigerina from the Bathonian of Poland. ...... (ABSTRACT)


von Hillebrandt, A., 2012. Are the Late Triassic to Early Jurassic aragonitic Oberhauserellidae (Robertinina) the ancestors of planktonic Foraminifera?. Neues Jahrbuch für Geologie und Paläontologie 266 (3), 199-215.


FUNCTIONAL MORPHOLOGY OF A NEW GENUS FROM THE ALBIAN OF THE LOWER SAXONY BASIN

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The new calcareous foraminiferal species Bartensteinites campanulatus nov. sp. from the Albian is described from the sediments of the Lower Saxony Basin. This taxon is designated as the type species of the new genus Bartensteinites nov. gen. Tyszka. This genus differs from Globorotalites and Conorotalites in having an aperture extended from the umbilicus through periphery to the spiral suture, as well as in possessing flush sutures on all side, from Cibicides in having flush chamber sutures and an extended aperture along the whole conical side up to the umbilicus, and from Carpenteria in lacking a keel along the periphery and having an extended aperture on the spiral side. B. campanulatus is interpreted as a vagile, epibenthic foraminifer with a well adapted test to the facultative sessile mode of life. Functional morphology of conical, planoconvex shapes was best suited for the suspension-feeding strategy, facilitated by temporal attachments to firm substrates. This is also confirmed by a distinct pattern of unusually fossilized pseudopodial tracks well preserved on apertural faces of some specimens. (ABSTRACT)


Tyszka, J., 2012. Bartensteinites campanulatus nov. gen, nov. sp. - functional morphology of a new foraminiferal genus from the Albian of the Lower Saxony Basin. Neues Jahrbuch für Geologie und Paläontologie 266 (3), 273-282.


SMALL PLANKTONIC FORAMINIFERA FROM THE BOREAL APTIAN HOHENEGGELSEN KB 9 CORE (HANNOVER, GERMANY)

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A planktonic foraminiferal biostratigraphy is established for the Boreal Lower to Upper Aptian sediments of the Hoheneggelsen KB 9 core (Lower Saxony Basin, northern Germany) and is correlated to planktonic foraminiferal records of coeval Tethyan sections (Switzerland, southeastern France, Italy, Spain, and Tunisia). Planktonic foraminiferal assemblages of the Hoheneggelsen KB 9 core are characterized by well preserved, small Praehedbergella, Blowiella and Leupoldina specimens and species that are known from the Tethyan Realm and indicate northern Tethyan ingressions during the early Aptian. Planktonic foraminiferal assemblages of the Hoheneggelsen KB 9 core reflect the profound palaeoceanographic change of the marine regime in the Lower Saxony Basin, starting in Lower Aptian sediments older than the 2 m thick mid Lower Aptian Fischschiefer Horizon of the Hoheneggelsen KB 9 core, which is correlated particularly with the Blowiella blowi Zone and considered as the Boreal equivalent of the Lower Aptian Oceanic Anoxic Event (OAE) 1a of the Tethyan Realm (Selli Level of Italy, Niveau Goguel of southeastern France). ...... (ABSTRACT)


Weiß, W., 2012. Small planktonic foraminiferal assemblages from the Boreal Aptian Hoheneggelsen KB 9 core (Hannover, northern Germany) - distribution, biostratigraphy and palaeoceanography. Neues Jahrbuch für Geologie und Paläontologie 266 (3), 283-317.


ALBIAN-CENOMANIAN FORAMINIFERA AND OSTRACODA FROM THE GLYNDEBOURNE BOREHOLE, SUSSEX, UK

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The Glyndebourne Borehole was drilled by the British Geological Survey in 1973 but the analysis of the foraminifera and ostracods remains unpublished: documented only in an un-published PhD thesis. The Gault Clay Formation, though thicker than that at Copt Point (Folkestone, U.K.), still has a number of hiatuses, especially near the base of the Middle Albian and at the Middle-Upper Albian boundary. The absence of the distinctive, glauconitic, 'Bed Xll' near the base of the Dispar Zone and the resulting differences in the ranges of key taxa has proved problematic. Throughout the remainder of the succession the distribution of the foraminifera closely follows that recorded at other locations in S.E. England (most notably Folkestone) but the uppermost Albian remains an issue for future research. The hiatus at the Albian-Cenomanian boundary was predicted by comparison to the succession at Beachy Head (Eastbourne), located a few kilometres to the south, and is much better understood in terms of biostratigraphy. (ABSTRACT)


Hart, M.B., Harris, C.S., 2012. Albian-Cenomanian Foraminifera and Ostracoda from the Glyndebourne Borehole, Sussex, U.K. Neues Jahrbuch für Geologie und Paläontologie 266 (3), 319-335.


FORAMINIFERAL FAUNA AND BIOTOPES OF A BARRIER ESTUARY SYSTEM

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A 66-sample study of estuarine foraminifera within St Georges Basin identified 30 species from three biotopes that are divided almost equally in diversity between calcareous and agglutinated forms. The latter, however, are twice as abundant as the former, and the species Ammobaculites exiguus, Portatrochammina sorosa, Rhumblerella subconica, and Ammonia aoteana represent 78% of the fauna. The main driver of biotope distribution is water depth or factors related to it. Faunal composition and biotope distribution are similar to those found in other estuaries in the region, suggesting the possibility of a “standard fauna” for Australian estuaries with limited connections to the open ocean. (ABSTRACT)


Strotz, L.C., 2012. Foraminiferal fauna and biotopes of a barrier estuary system: St Georges Basin, New South Wales, Australia. Journal of Foraminiferal Research 42 (4), 369-382.


RECORD OF ELONGATE-CYLINDRICAL FORAMINIFERA ACROSS THE EOCENE–OLIGOCENE TRANSITION IN THE NORTH ATLANTIC

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The Eocene-Oligocene transition (EOT) at ∼34 Ma constitutes one of the major episodes of climate change that occurred in the last 50 myr, associated with the establishment of permanent Antarctic ice sheets and the initiation of meridional overturning circulation. We present a high-resolution quantitative study (>125-μm fraction) of a group of calcareous, deep-sea, benthic foraminifera with elongate-cylindrical morphologies (Elongate Gp.) across the EOT at high latitudes in the North Atlantic Ocean (ODP Hole 647A). This group experienced significant declines in abundance and diversity during periods of global cooling, disappearing almost completely during the mid-Pleistocene Climate Transition. ...... (ABSTRACT)


Ortiz, S., Kaminski, M.A., 2012. Record of deep-sea, benthic elongate-cylindrical foraminifera across the Eocene-Oligocene transition in the North Atlantic Ocean (ODP Hole 647A). Journal of Foraminiferal Research 42 (4), 345-368.


EMENDATION OF Cibicides antarcticus BASED ON MOLECULAR, MORPHOLOGICAL, AND ECOLOGICAL DATA

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Shallow water Antarctic cibicidids are traditionally identified as Cibicides refulgens or Cibicidoides lobatulus. However, a recent phylogenetic study based on SSU rDNA sequence data has demonstrated that these Antarctic cibicidids form a well-supported clade that branches sister to Mediterranean C. refulgens and is only distantly related to C. lobatulus. Based on these DNA sequences, and a detailed scanning electron microscopic examination of material from Explorers Cove (McMurdo Sound), we place Antarctic cibicidids in a separate species Cibicides antarcticus (Saidova, 1975), which is emended here with molecular, morphological, and ecological features. (ABSTRACT)


Schweizer, M., Bowser, S.S., Korsum, S., Pawlowski, J., 2012. Emendation of Cibicides antarcticus (Saidova, 1975) based on molecular, morphological, and ecological data. Journal of Foraminiferal Research 42 (4), 340-344.


HIGH BENTHIC FORAMINIFERA DIVERSITY IN POLLUTED BUSAN NORTH PORT (KOREA)

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Surface sediments were collected from Busan North Port (southern coast of Korea) and the outer port area (OPA) in February and August 2009 to ascertain the distribution of benthic foraminifera and assess controlling environmental factors. ...... The OPA is characterized by inner continental-shelf environments. These areal distinctions corresponded well to cluster- and principal component-analysis results based on foraminiferal-assemblage and heavy-metal data. The degree of organic enrichment and heavy-metal concentration in the sediments were major factors explaining the distributions of the foraminiferal assemblage. ...... (ABSTRACT)


Ung Choi, J., An, S., 2012. High benthic foraminiferal diversity in polluted Busan North Port (Korea). Journal of Foraminiferal Research 42 (4), 327-339.


DISTRIBUTION OF FORAMINIFERA OF THE POVERTY CONTINENTAL MARGIN, NEW ZEALAND: IMPLICATIONS FOR SEDIMENT TRANSPORT

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Foraminiferal assemblages were used to investigate the nature of sedimentation on the tectonically active Poverty continental margin (PCM) of New Zealand. Recent research around the world has been focused on understanding the sedimentary functioning of small mountainous rivers to the global sediment budget, and this study is part of a greater effort to define the processes that link sediment source and sink of such a system in New Zealand. Fifty-five surface samples from box, gravity, and multi-cores from the shelf and slope of the PCM were used to document the distribution of modern benthic foraminifera. Also, twenty samples from two gravity cores retrieved from Poverty Canyon, a hypothesized conduit of sediment to the deep ocean, were analyzed to evaluate the record of down-slope sediment transport. ...... (ABSTRACT)


Culver, S.J., Camp, R.L., Walsh, J.P., Hayward, B.W., Corbett, D.R., Alexander, C.R., 2012. Distribution of foraminifera of the Poverty continental margin, New Zealand: Implications for sediment transport. Journal of Foraminiferal Research 42 (4), 305-326.


OLIGOCENE FORAMINIFERA FROM THE FUENTE CALDERA SECTION, SPAIN: TAXONOMY AND PALAEONVIRONMENTAL INFERENCES

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The effects of Oligocene paleoclimatic and paleoenvironmental events at lower latitudes have not been well defined, and the timing and extent of a proposed warming period in the late Oligocene are not clear. The study of benthic foraminifera from the upper bathyal Fuente Caldera section in southern Spain may help reconstruct the Oligocene paleoenvironmental turnover in the western Tethys. Rupelian and Chattian sediments from Fuente Caldera consist of hemipelagic marls intercalated with turbiditic sandstones. Based on a closely spaced sample collection, we present a quantitative analysis of benthic foraminiferal assemblage changes, and a detailed taxonomic study of 19 of the most abundant and paleoenvironmentally important species, belonging to the asterigerinids, rosalinids and bolivinids. ...... (ABSTRACT)


Fenero, R., Thomas, E., Alegret, L., Molina, E., 2012. Oligocene Benthic foraminifera from the Fuente Caldera Section (Spain, Western Tethys): Taxonomy and paleoenvironmental inferences. Journal of Foraminiferal Research 42 (4), 286-304.


TAXONOMIC REEXAMINATION AND TYPE-LOCALITY ASSEMBLAGE CHARACTERIZATION OF Hedbergella yezoana

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The late Albian planktonic foraminifera Hedbergella trocoidea yezoana Takayanagi and Iwamoto, 1962, from Japan, whose primary distinguishing feature is 7–8 chambers in the final whorl, has been internationally cited with a species rank as Hedbergella yezoana. Still, its taxonomic position is not well understood, as manifested by the fact that published hypotypes have six or fewer chambered forms, and such ambiguity is due partly to a lack of updated knowledge about the primary types (a holotype and single paratype), topotypes, and hypotypes from the northwestern Pacific region. This study reexamines the species concept of Hd. yezoana through uncoated SEM observations of the primary types and newly obtained type-locality material. ...... (ABSTRACT)


Ando, A., 2012. Taxonomic reexamination and type-locality assemblage characterization of the late Albian planktonic foraminifera Hedbergella yezoana Takayanagi and Iwamoto, 1962, from Japan. Journal of Foraminiferal Research 42 (4), 271-285.


MINING MORPHOLOGICAL EVOLUTION IN MICROFOSSILS USING VOLUME DENSITY DIAGRAMS

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A technique is explored to visualize series of bivariate morphometric measurements of microfossil shells through geological time with the help of 3D-animated volume-density distributions. Visualization tests were performed using two existing and published sets of morphometric data, i.e., the Neogene coccolithophorid group Calcidiscus leptoporus-Calcidiscus macintyrei and the planktonic foraminifera plexus of Globorotalia menardii. The technique converts series of downcore bivariate morphometric shell data into a continuous frequency distribution, which can be investigated with the help of a graphical data mining tool called Voxler from Golden Software. This tool allowed us to compose and animate complex subsurface structures raised from morphometric measurements of microfossils, and so provides an intuitive, comprehensive insight into the structure and dynamics of complicated evolutionary patterns. With upcoming future large morphometric data sets for oceanic microfossils, this instructive illustration method may hopefully serve to raise more interest in studying topics like morphological evolution, speciation and advances to achieve more universial species concepts needed so strongly in paleontology. ...... (ABSTRACT)


Knappertsbusch, M.W., Mary, Y., 2012. Mining morphological evolution in microfossils using volume density diagrams. Palaeontologia Electronica 15 (3); 7T, 29p


THE ONSET OF THE BARREMIAN ANOXIC CONDITIONS IN THE BOREAL REALM

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...... For this study 27 samples covering the Hauterivian/Barremian boundary interval were investigated with respect to their CaCO3 and total organic contents (TOC), stable isotope composition (δ13Corg,   δ13CCaCO3,   δ18OCaCO3) and their micropalaeontology (foraminifera). The samples were analysed in order to better understand the onset of the Barremian anoxic conditions in the Boreal Realm. The data obtained show that shifts of the environmental parameters are reflected by the mudstone-marl alternation. The dark mudstones reflect cooler surface water temperatures and a lower oxygen content, while the pale marls were deposited under warm surface water conditions. These bedding rhythms are thought to be the result of climatic variations in the Milankovitch Band (10Ka–1Ma). This study further documents that the Hauterivian/Barremian transition is characterised by a deterioration of the living conditions for benthic organisms. This is indicated by the decline of several foraminiferal genera, by decreasing generic richness and by a coeval increase in the abundances of specific taxa. The TOC content and the isotopic composition of the organic carbon support these findings. A morphogroup analysis of the benthic foraminifera indicates changes of the habitats from mainly infaunal in the late Hauterivian to more epifaunal in the early Barremian. Due to this dramatic decline of infaunal forms in the laminated, TOC-rich mudstones of the lowermost Barremian, suboxic to anoxic conditions are postulated for these sediments. The bottom water must, however, have contained some oxygen at least, as is indicated by a few epifaunal genera that became very abundant (e.g. Ammodiscus). A major regression around the Hauterivian/Barremian boundary caused a closing of the seaway to the Tethys, resulting in a significantly reduced water exchange and the establishment of anoxic conditions.

(ABSTRACT)


Löb, C., Mutterlose, J., 2012. The onset of anoxic conditions in the early Barremian of the Boreal Realm evidenced by benthic foraminifera. Revue de Micropaléontologie 55 (3), 113-126.


MEDITERRANEAN OUTFLOW WATER DURING THE MESSINIAN

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Messinian foraminiferal stable oxygen and carbon isotopes of the Montemayor-1 core (Guadalquivir Basin, SW Spain) have been investigated. This record is exceptional to study the Mediterranean Outflow Water (MOW) impact on the Atlantic meridional overturning circulation (AMOC) and global climate during the Messinian because the core is near the Guadalhorce Corridor, the last Betic gateway to be closed during the early Messinian. Our results allow dating accurately its closure at 6.18 Ma. Constant benthic d18O values, high difference between benthic and planktonic d18O, and low sedimentation rates before 6.18 Ma indicate the presence of a two-layer water column, with bottom winnowing due to an enhanced Mediterranean outflow current. The enhanced contribution of dense MOW to the North Atlantic Ocean likely fostered the formation of North Atlantic Deep Water (NADW). After 6.18 Ma, benthic d18O values parallel that of the global glacioeustatic curve, the difference between benthic and planktonic d18O is low, and sedimentation rates considerably increased. This indicates a good vertical mixing of the water column, interruption of the MOW, and a dominant glacioeustatic control on the isotopic signatures. According to the role of MOW in the modern Atlantic thermohaline circulation, the reduction of the MOW after the closure of the Guadalhorce Corridor might have resulted in a decreased NADW formation rate between 6.0 and 5.5 Ma weakening the AMOC and promoting northern hemisphere cooling. (ABSTRACT)


Pérez-Asensio, J.N., Aguirre, J., Schmiedl, G., Civis, J., 2012. Impact of restriction of the Atlantic-Mediterranean gateway on the Mediterranean Outflow Water and eastern Atlantic circulation during the Messinian. Paleoceanography 27, PA3222, doi:10.1029/2012PA002309.


BIOEROSION BY MICROBIAL EUENDOLITHS IN BENTHIC FORAMINIFERA

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A monitoring survey of the coastal area facing the industrial area of Portoscuso-Portovesme (South-Western Sardinia, Italy) revealed intense bioerosional processes. Benthic foraminifera collected at the same depth (about 2 m) but at different distances from the pollution source show extensive microbial infestation, anomalous Mg/Ca molar ratios and high levels of heavy metals in the shell associated with a decrease in foraminifera richness, population density and biodiversity with the presence of morphologically abnormal specimens. We found that carbonate dissolution induced by euendoliths is selective, depending on the Mg content and morpho-structural types of foraminiferal taxa. This study provides evidences for a connection between heavy metal dispersion, decrease in pH of the sea-water and bioerosional processes on foraminifera.

(ABSTRACT)


Cherchi, A., Buosi, C., Zuddas, P., De Giudici, G., 2012. Bioerosion by microbial euendoliths in benthic foraminifera from heavy metal-polluted coastal environments of Portovesme (South-Western Sardinia, Italy). Biogeosciences Discuss 9, 11103-11137.


CENOZOIC STRATIGRAPHY OF TAIWAN

Shallow marine sequences of the northern South China Sea (SCS) are uplifted and exposed by plate convergence in the Taiwan mountain belt. These deposits provide detailed geological information about the rifting event, stratigraphy, sedimentology, paleoclimate and paleoceanography of the shallow SCS to compare with what are recorded in the ODP 1148 deep-sea core. Seismic surveys and marine micropalentological studies show that Eocene sequences in the offshore Taiwan Strait and onland Taiwan mountain belt are all deposited in rifting basins and are covered unconformably by the Late Oligocene-Neogene post-rifting strata. ...... (ABSTRACT)


Huang, C.-Y., Yen, Y., Zhao, Q.H., Lin, C.-T., 2012. Cenozoic stratigraphy of Taiwan: Window into rifting, stratigraphy and paleoceanography of South China Sea. Chinese Science Bulletin 57 (24), 3130-3149.


PALAEOBIOGEOGRAPHIC SIGNIFICANCE OF EARLY CRETACEOUS B. balkhanica IN THE PERI-TETHYAN DOMAIN

The poorly known larger benthic foraminifer Balkhania balkhanica Mamontova is reported from the Tirgan Formation (Upper Barremian-Lower Aptian) in the northeastern part of Iran. It was so far only known from Iran (Kopet Dagh and Central Iran), Turkmenistan, and central Afghanistan. Obviously, B. balkhanica possessed a limited distributional area overlapping largely with that of the dasycladalean alga Kopetdagaria sphaerica Maslov (Turkmenistan, Iran, Georgia, Bulgaria, Romania), Conradella bakalovae (Conrad and Peybernès) (Tibet?, Georgia, Bulgaria, Romania), and other taxa. These taxa typify the so-called Carpatho-Pontic algal bioprovince sensu Bucur (2000), which is emended and replaced with the new name Carpatho-Cimmerian bioprovince being part of the former northern (= Eurasian) margin of the Neo-Tethys. The present case study provides a further example that the investigation of the distribution pattern of larger benthic foraminifera, together with dasycladalean green algae, may provide a useful proxy in paleotectonic and paleogeographic reconstructions of the Peri-Tethyan domain. (ABSTRACT)


Abad, M.T.K., Schlagintweit, F., Vaziri, S.H., Aryaei, A.A., Ashouri, A.R., 2012. Balkhania balkhanica Mamontova, 1966 (benthic foraminifera) and Kopetdagaria sphaerica Maslov, 1960 (dasycladalean alga) from the Lower Cretaceous Tirgan Formation of the Kopet Dagh mountain range (NE Iran) and their paleobiogeographic significance. Facies, doi:10.1007/s10347-012-0323-3


RECOLONISATION OF NEW HABITATS BY MEIOBENTHOS IN THE DEEP ARCTIC OCEAN

Commercial exploitation and abrupt changes of the natural conditions may have severe impacts on the Arctic deep-sea ecosystem. The present recolonisation experiment mimicked a situation after a catastrophic disturbance (e.g. by turbidites caused by destabilised continental slopes after methane hydrate decomposition) and investigated whether the recolonisation of a deep-sea habitat by meiobenthic organisms is fostered by variations in nutrition and/or sediment structure. Two “Sediment Tray Free Vehicles” were deployed for 1 year in summer 2003 at 2,500 m water depth in the Arctic deep-sea in the eastern Fram Strait. ...... After 1 year, meiobenthos abundances and various sediment-related environmental parameters were investigated. Foraminifera were generally the most successful group: they dominated all treatments and accounted for about 87 % of the total meiobenthos. Colonising meiobenthos specimens were generally smaller compared to those in the surrounding deep-sea sediment, suggesting an active recolonisation by juveniles. ...... (ABSTRACT)


Freese, D., Schewe, I., Kanzog, C., Soltwedel, T., Klages, M., 2012. Recolonisation of new habitats by meiobenthic organisms in the deep Arctic Ocean: an experimental approach. Polar Biology, doi:10.1007/s00300-012-1223-2


MEIOBENTHOS IN THE DEEP WHITE SEA AND THEIR TEMPORAL VARIATIONS

...... This study represents the first major study of the meiobenthos from the deep White Sea. The composition of the meiobenthic community, density and vertical distribution was studied during four sampling occasions in the deepest part of the Kandalaksha Depression (White Sea) in July 1998, October 1998, May 1999 and November 1999. Samples were collected from a depth of 270 m with the aid of a multicorer. ...... The most abundant meiobenthic group was Foraminifera (59 %), followed by Nematoda (26 %) and Harpacticoida (7 %). These relative and absolute abundance values are comparable with the same depth interval in Arctic and temperate regions. The density of foraminiferans and nematodes was higher in the autumn and lower in the summer. ...... (ABSTRACT)


Miljutin, D.M., Miljutina, M.A., Mokievsky, V.O., Tchesunov, A.V., 2012. Benthic meiofaunal density and community composition in the deep White Sea and their temporal variations. Polar Biology, doi:10.1007/s00300-012-1226-z


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