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Université de Fribourg

Assessing the impact of diagenesis on foraminiferal geochemistry from a low latitude, shallow-water drift deposit

Stainbank, Stephanie ; Spezzaferri, Silvia ; Boever, Eva De ; Bouvier, Anne-Sophie ; Chilcott, Colin ; Leau, Erica ; Foubert, Anneleen ; Kunkelova, Tereza ; Pichevin, Laetitia ; Raddatz, Jacek ; Rüggeberg, Andres ; D.Wright, James ; M.Yu, Siyao ; Zhang, Manlin ; Kroon, Dick

In: Earth and Planetary Science Letters, 2020, vol. 545, p. 116390

Due to their large heat and moisture storage capabilities, the tropics are fundamental in modulating both regional and global climate. Furthermore, their thermal response during past extreme warming periods, such as super interglacials, is not fully resolved. In this regard, we present high-resolution (analytical) foraminiferal geochemical (δ18O and Mg/Ca) records for the last 1800 kyr from...

Université de Fribourg

Cold-water coral mound archive provides unique insights into intermediate water mass dynamics in the alboran sea during the last deglaciation

Fentimen, Robin ; Feenstra, Eline ; Rüggeberg, Andres ; Vennemann, Torsten ; Hajdas, Irka ; Adatte, Thierry ; Van Rooij, David ; Foubert, Anneleen

In: Frontiers in Marine Science, 2020, vol. 7, p. -

The Alboran Sea is widely recognized to host numerous cold-water coral ecosystems, including the East Melilla Coral Province. Yet, their development through time and response to climatic variability has still to be fully understood. Based on a combined investigation of benthic foraminiferal assemblages, foraminiferal stable isotope compositions, grain size analysis, sediment geochemistry, and...

Université de Fribourg

Palynological study of carbonated mounds during the holocene along the atlantic and mediterranean moroccan margins

Rachid, Jihad ; Hssaida, Touria ; Hamoumi, Naima ; Terhzaz, Loubna ; Spezzaferri, Silvia ; Frank, Norbert ; Daghor, Lamia

In: Review of Palaeobotany and Palynology, 2020, vol. 278, p. 104213

A palynological study of carbonate mounds of Atlantic and Mediterranean Moroccan margins was conducted on sediment boxcores MD13-3441, MD13-3456, MD13-3461, MD13-3465, MD13-3468 collected during the oceanographic cruise MD 194/Eurofleet - GATEWAY, which took place on June 2013.The organic remaining revealed a dominance of dinoflagellate cysts over the continental fraction, which showed very...

Université de Fribourg

Living (stained) foraminifera in the Lesser Syrtis (Tunisia): influence of pollution and substratum

El Kateb, Akram ; Beccari, Valentina ; Stainbank, Stephanie ; Spezzaferri, Silvia ; Coletti, Giovanni

In: PeerJ, 2020, p. e8839

Foraminifera are protozoans with biomineralized tests that can be successfully used as a low cost monitoring tool to assess the health status of marine environments. Living benthic foraminiferal assemblages can provide essential information on natural and/or anthropogenic stresses and provide baseline conditions for studies on fossil material. Several studies have highlighted the negative impact...

Université de Fribourg

Macro- and micro-fauna from cold seeps in the Palmahim Disturbance (Israeli off-shore), with description of Waisiuconcha corsellii n.sp. (Bivalvia, Vesicomyidae)

Basso, D. ; Beccari, V. ; Almogi-Labin, A. ; Hyams-Kaphzan, O. ; Weissman, A. ; Makovsky, Y. ; Rüggeberg, A. ; Spezzaferri, Silvia

In: Deep Sea Research Part II: Topical Studies in Oceanography, 2020, vol. 171, p. 104723

Chemosymbiotic micro- and macro-fauna related to cold-seep sites were recovered in the Palmahim Disturbance (PD), offshore Israel, during EU EUROFLEETS2 SEMSEEP Cruise, by box-coring and Remotely Operated Vehicle (ROV) dives. No live macrofauna was identified in the collected sediments, with the exception of the seep-related crustacean Calliax lobata (de Gaillande and Lagardère, 1966)....

Université de Fribourg

Foraminiferal-based biotic indices to assess the ecological quality status of the Gulf of Gabes (Tunisia): Present limitations and future perspectives

Kateb, Akram El ; Stalder, Claudio ; Martínez-Colón, Michael ; Mateu-Vicens, Guillem ; Francescangeli, Fabio ; Coletti, Giovanni ; Stainbank, Stephanie ; Spezzaferri, Silvia

In: Ecological Indicators, 2020, vol. 111, p. 105962

Biotic indices are tools to assess the ecological status of marine systems, and can be based on different metrics (such as ecological groups, specific diversity). The present study applies five biotic indices based on living (stained) benthic foraminiferal assemblages to assess ecological conditions in a wide area of the Mediterranean Sea in the heavily polluted Gulf of Gabes and along the...

Université de Fribourg

Impact of bottom water currents on benthic foraminiferal assemblages in a cold-water coral environment: The Moira Mounds (NE Atlantic)

Fentimen, Robin ; Lim, Aaron ; Rüggeberg, Andres ; Wheeler, Andrew J. ; Rooij, David Van ; Foubert, Anneleen

In: Marine Micropaleontology, 2020, vol. 154, p. 101799

Strong bottom currents play a key role in cold-water coral environments by shaping their morphology and providing the necessary food for the corals to thrive. This study investigates the differences between living and dead benthic foraminiferal assemblages in such environments, more precisely on the Moira Mounds (NE Atlantic). A specific focus is to understand the role of currents and their...

Université de Fribourg

Solenosmilia variabilis-bearing cold-water coral mounds off Brazil

Raddatz, J. ; Titschack, J. ; Frank, N. ; Freiwald, A. ; Conforti, A. ; Osborne, A. ; Skornitzke, S. ; Stiller, W. ; Rüggeberg, Andres ; Voigt, Silke ; Albuquerque, A. L. S. ; Vertino, A. ; Schröder-Ritzrau, A. ; Bahr, A.

In: Coral Reefs, 2020, vol. 39, no. 1, p. 69–83

Cold-water corals (CWC), dominantly Desmophyllum pertusum (previously Lophelia pertusa), and their mounds have been in the focus of marine research during the last two decades; however, little is known about the mound-forming capacity of other CWC species. Here, we present new 230Th/U age constraints of the relatively rarely studied framework-building CWC Solenosmilia variabilis from a mound...

Université de Fribourg

Constraining the formation of authigenic carbonates in a seepage-affected cold-water coral mound by lipid biomarkers

Feenstra, Eline Juliette ; Birgel, Daniel ; Heindel, Katrin ; Wehrmann, Laura M. ; Jaramillo‐Vogel, David ; Grobéty, Bernard ; Frank, Norbert ; Hancock, Leanne G. ; Van Rooij, David ; Peckmann, Jörn ; Foubert, Anneleen

In: Geobiology, 2020, vol. 18, no. 2, p. 185–206

Cold‐water coral (CWC) mounds are build‐ups comprised of coral‐dominated intervals alternating with a mixed carbonate‐siliciclastic matrix. At some locations, CWC mounds are influenced by methane seepage, but the impact of methane on CWC mounds is poorly understood. To constrain the potential impact of methane on CWC mound growth, lipid biomarker investigations were combined with...

Université de Fribourg

The genus Amphistegina (benthic foraminifera): distribution along the southern Tunisian coast

Kateb, Akram El ; Stalder, Claudio ; Stainbank, Stephanie ; Fentimen, Robin ; Spezzaferri, Silvia

In: BioInvasions Records, 2018, vol. 7, no. 4, p. 391–398

The benthic foraminiferal genus Amphistegina is currently expanding its range in the Mediterranean Sea after being introduced through the Suez Canal from the Red Sea. Over the previous decade, Amphistegina spp. has colonized the eastern part of the Mediterranean Sea including the Egyptian and Libyan coasts, but the present southern limit in the Mediterranean Sea is along the southern Tunisian...