Articles | Volume 44, issue 1
https://doi.org/10.5194/jm-44-79-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/jm-44-79-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Review article
| 
20 Mar 2025
Review article |
| 20 Mar 2025
| 20 Mar 2025
Recent benthic foraminifera communities offshore of Thwaites Glacier in the Amundsen Sea, Antarctica: implications for interpretations of fossil assemblages
Asmara A. Lehrmann
CORRESPONDING AUTHOR
Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA
Department of Geological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
Rebecca L. Totten
Department of Geological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
Department of Museum Research and Collections and the Alabama Museum of Natural History, Tuscaloosa, AL 35487, USA
Julia S. Wellner
Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA
Claus-Dieter Hillenbrand
British Antarctic Survey, Cambridge, CB3 0ET, UK
Svetlana Radionovskaya
British Antarctic Survey, Cambridge, CB3 0ET, UK
Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK
R. Michael Comas
Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA
Robert D. Larter
British Antarctic Survey, Cambridge, CB3 0ET, UK
Alastair G. C. Graham
School of Earth and Environmental Sciences, Cardiff University, Cardiff, CF10 3AT, UK
James D. Kirkham
British Antarctic Survey, Cambridge, CB3 0ET, UK
Kelly A. Hogan
British Antarctic Survey, Cambridge, CB3 0ET, UK
Victoria Fitzgerald
Department of Geological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
Rachel W. Clark
Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA
Becky Hopkins
School of Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO143ZH, UK
Department of Earth, Ocean and Ecological Sciences, University of Liverpool, Liverpool, L69 3GP, UK
Allison P. Lepp
Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
Elaine Mawbey
British Antarctic Survey, Cambridge, CB3 0ET, UK
Rosemary V. Smyth
Department of Geological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
Lauren E. Miller
Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
James A. Smith
British Antarctic Survey, Cambridge, CB3 0ET, UK
Frank O. Nitsche
Lamont-Doherty Earth Observatory, Columbia University, New York, NY 10027, USA
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Yavor Kostov, Paul R. Holland, Kelly A. Hogan, James A. Smith, Nicolas C. Jourdain, Pierre Mathiot, Anna Olivé Abelló, Andrew H. Fleming, and Andrew J. S. Meijers
EGUsphere, https://doi.org/10.5194/egusphere-2025-2423, https://doi.org/10.5194/egusphere-2025-2423, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
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Icebergs ground when they reach shallow topography such as Bear Ridge in the Amundsen Sea. Grounded icebergs can block the transport of sea-ice and create areas of higher and lower sea-ice concentration. We introduce a physically and observationally motivated representation of grounding in an ocean model. In addition, we improve the way simulated icebergs respond to winds, ocean currents, and density differences in sea water. We analyse the forces acting on freely floating and grounded icebergs.
Kevin Hank, Robert J. Arthern, C. Rosie Williams, Alex M. Brisbourne, Andrew M. Smith, James A. Smith, Anna Wåhlin, and Sridhar Anandakrishnan
EGUsphere, https://doi.org/10.5194/egusphere-2025-764, https://doi.org/10.5194/egusphere-2025-764, 2025
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The slipperiness beneath ice sheets is a key source of uncertainty in sea level rise projections. Using both observations and model output, we infer the most probable representation of basal slipperiness in ice sheet models, enabling more accurate projections. For Pine Island Glacier, our results provide support for a Coulomb-type sliding law and widespread low effective pressures, potentially increasing sliding velocities in prognostic simulations and, hence, sea level rise projections.
James W. Marschalek, Edward Gasson, Tina van de Flierdt, Claus-Dieter Hillenbrand, Martin J. Siegert, and Liam Holder
Geosci. Model Dev., 18, 1673–1708, https://doi.org/10.5194/gmd-18-1673-2025, https://doi.org/10.5194/gmd-18-1673-2025, 2025
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Ice sheet models can help predict how Antarctica's ice sheets respond to environmental change, and such models benefit from comparison to geological data. Here, we use an ice sheet model output and other data to predict the erosion of debris and trace its transport to where it is deposited on the ocean floor. This allows the results of ice sheet modelling to be directly and quantitively compared to real-world data, helping to reduce uncertainty regarding Antarctic sea level contribution.
Flavia Boscolo-Galazzo, David Evans, Elaine M. Mawbey, William R. Gray, Paul N. Pearson, and Bridget S. Wade
Biogeosciences, 22, 1095–1113, https://doi.org/10.5194/bg-22-1095-2025, https://doi.org/10.5194/bg-22-1095-2025, 2025
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Here we compare the Mg / Ca and oxygen isotope signatures for 57 recent to fossil species of planktonic foraminifera for the last 15 Myr. We find the occurrence of lineage-specific offsets in Mg / Ca conservative between ancestor-descendent species. Taking into account species kinship significantly improves temperature reconstructions, and we suggest that the occurrence of Mg / Ca offsets in modern species results from their evolution when ocean properties were different from today's.
Frida S. Hoem, Karlijn van den Broek, Adrián López-Quirós, Suzanna H. A. van de Lagemaat, Steve M. Bohaty, Claus-Dieter Hillenbrand, Robert D. Larter, Tim E. van Peer, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
J. Micropalaeontol., 43, 497–517, https://doi.org/10.5194/jm-43-497-2024, https://doi.org/10.5194/jm-43-497-2024, 2024
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The timing and impact of onset of Antarctic Circumpolar Current (ACC) on climate and Antarctic ice are unclear. We reconstruct late Eocene to Miocene southern Atlantic surface ocean environment using microfossil remains of dinoflagellates (dinocysts). Our dinocyst records shows the breakdown of subpolar gyres in the late Oligocene and the transition into a modern-like oceanographic regime with ACC flow, established frontal systems, Antarctic proximal cooling, and sea ice by the late Miocene.
Joseph A. Ruggiero, Reed P. Scherer, Joseph Mastro, Cesar G. Lopez, Marcus Angus, Evie Unger-Harquail, Olivia Quartz, Amy Leventer, and Claus-Dieter Hillenbrand
J. Micropalaeontol., 43, 323–336, https://doi.org/10.5194/jm-43-323-2024, https://doi.org/10.5194/jm-43-323-2024, 2024
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We quantify sea surface temperature (SST) in the past Southern Ocean using the diatom Fragilariopsis kerguelensis that displays variable population with SST. We explore the use of this relatively new proxy by applying it to sediment assemblages from the Sabrina Coast and Amundsen Sea. We find that Amundsen Sea and Sabrina Coast F. kerguelensis populations are different from each other. An understanding of F. kerguelensis dynamics may help us generate an SST proxy to apply to ancient sediments.
Indrani Das, Jowan Barnes, James Smith, Renata Constantino, Sidney Hemming, and Laurie Padman
EGUsphere, https://doi.org/10.5194/egusphere-2024-1564, https://doi.org/10.5194/egusphere-2024-1564, 2024
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George VI Ice Shelf (GVIIS) on the Antarctic Peninsula is currently thinning and the glaciers feeding it are accelerating. Geologic evidence indicates that GVIIS had disintegrated several thousand years ago due to ocean and atmosphere warming. Here, we use remote sensing and numerical modeling to show that strain thinning reduces buttressing of grounded ice, creating a positive feedback of accelerated ice inflow to the southern GVIIS, likely making it more vulnerable than the northern sector.
Allison P. Lepp, Lauren E. Miller, John B. Anderson, Matt O'Regan, Monica C. M. Winsborrow, James A. Smith, Claus-Dieter Hillenbrand, Julia S. Wellner, Lindsay O. Prothro, and Evgeny A. Podolskiy
The Cryosphere, 18, 2297–2319, https://doi.org/10.5194/tc-18-2297-2024, https://doi.org/10.5194/tc-18-2297-2024, 2024
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Shape and surface texture of silt-sized grains are measured to connect marine sediment records with subglacial water flow. We find that grain shape alteration is greatest in glaciers where high-energy drainage events and abundant melting of surface ice are inferred and that the surfaces of silt-sized sediments preserve evidence of glacial transport. Our results suggest grain shape and texture may reveal whether glaciers previously experienced temperate conditions with more abundant meltwater.
Marion A. McKenzie, Lauren E. Miller, Allison P. Lepp, and Regina DeWitt
Clim. Past, 20, 891–908, https://doi.org/10.5194/cp-20-891-2024, https://doi.org/10.5194/cp-20-891-2024, 2024
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Records of the interaction between land and glacial ice movement in the Puget Lowland of Washington State are used to interpret that solid Earth movement provided stability to this marine-terminating glacial ice for at least 500 years. These results are significant because this landscape is similar to parts of the Greenland Ice Sheet and the Antarctic Peninsula, indicating that the interactions seen in this area are applicable to modern glaciated regions.
Benoit S. Lecavalier, Lev Tarasov, Greg Balco, Perry Spector, Claus-Dieter Hillenbrand, Christo Buizert, Catherine Ritz, Marion Leduc-Leballeur, Robert Mulvaney, Pippa L. Whitehouse, Michael J. Bentley, and Jonathan Bamber
Earth Syst. Sci. Data, 15, 3573–3596, https://doi.org/10.5194/essd-15-3573-2023, https://doi.org/10.5194/essd-15-3573-2023, 2023
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The Antarctic Ice Sheet Evolution constraint database version 2 (AntICE2) consists of a large variety of observations that constrain the evolution of the Antarctic Ice Sheet over the last glacial cycle. This includes observations of past ice sheet extent, past ice thickness, past relative sea level, borehole temperature profiles, and present-day bedrock displacement rates. The database is intended to improve our understanding of past Antarctic changes and for ice sheet model calibrations.
Alice C. Frémand, Peter Fretwell, Julien A. Bodart, Hamish D. Pritchard, Alan Aitken, Jonathan L. Bamber, Robin Bell, Cesidio Bianchi, Robert G. Bingham, Donald D. Blankenship, Gino Casassa, Ginny Catania, Knut Christianson, Howard Conway, Hugh F. J. Corr, Xiangbin Cui, Detlef Damaske, Volkmar Damm, Reinhard Drews, Graeme Eagles, Olaf Eisen, Hannes Eisermann, Fausto Ferraccioli, Elena Field, René Forsberg, Steven Franke, Shuji Fujita, Yonggyu Gim, Vikram Goel, Siva Prasad Gogineni, Jamin Greenbaum, Benjamin Hills, Richard C. A. Hindmarsh, Andrew O. Hoffman, Per Holmlund, Nicholas Holschuh, John W. Holt, Annika N. Horlings, Angelika Humbert, Robert W. Jacobel, Daniela Jansen, Adrian Jenkins, Wilfried Jokat, Tom Jordan, Edward King, Jack Kohler, William Krabill, Mette Kusk Gillespie, Kirsty Langley, Joohan Lee, German Leitchenkov, Carlton Leuschen, Bruce Luyendyk, Joseph MacGregor, Emma MacKie, Kenichi Matsuoka, Mathieu Morlighem, Jérémie Mouginot, Frank O. Nitsche, Yoshifumi Nogi, Ole A. Nost, John Paden, Frank Pattyn, Sergey V. Popov, Eric Rignot, David M. Rippin, Andrés Rivera, Jason Roberts, Neil Ross, Anotonia Ruppel, Dustin M. Schroeder, Martin J. Siegert, Andrew M. Smith, Daniel Steinhage, Michael Studinger, Bo Sun, Ignazio Tabacco, Kirsty Tinto, Stefano Urbini, David Vaughan, Brian C. Welch, Douglas S. Wilson, Duncan A. Young, and Achille Zirizzotti
Earth Syst. Sci. Data, 15, 2695–2710, https://doi.org/10.5194/essd-15-2695-2023, https://doi.org/10.5194/essd-15-2695-2023, 2023
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This paper presents the release of over 60 years of ice thickness, bed elevation, and surface elevation data acquired over Antarctica by the international community. These data are a crucial component of the Antarctic Bedmap initiative which aims to produce a new map and datasets of Antarctic ice thickness and bed topography for the international glaciology and geophysical community.
Kelly A. Hogan, Katarzyna L. P. Warburton, Alastair G. C. Graham, Jerome A. Neufeld, Duncan R. Hewitt, Julian A. Dowdeswell, and Robert D. Larter
The Cryosphere, 17, 2645–2664, https://doi.org/10.5194/tc-17-2645-2023, https://doi.org/10.5194/tc-17-2645-2023, 2023
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Delicate sea floor ridges – corrugation ridges – that form by tidal motion at Antarctic grounding lines record extremely fast retreat of ice streams in the past. Here we use a mathematical model, constrained by real-world observations from Thwaites Glacier, West Antarctica, to explore how corrugation ridges form. We identify
till extrusion, whereby deformable sediment is squeezed out from under the ice like toothpaste as it settles down at each low-tide position, as the most likely process.
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, and David H. Roberts
The Cryosphere, 17, 1821–1837, https://doi.org/10.5194/tc-17-1821-2023, https://doi.org/10.5194/tc-17-1821-2023, 2023
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The Northeast Greenland Ice Stream is a major outlet of the Greenland Ice Sheet. Some of its outlet glaciers and ice shelves have been breaking up and retreating, with inflows of warm ocean water identified as the likely reason. Here we report direct measurements of warm ocean water in an unusual lake that is connected to the ocean beneath the ice shelf in front of the 79° N Glacier. This glacier has not yet shown much retreat, but the presence of warm water makes future retreat more likely.
James W. Marschalek, Edward Gasson, Tina van de Flierdt, Claus-Dieter Hillenbrand, Martin J. Siegert, and Liam Holder
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-8, https://doi.org/10.5194/gmd-2023-8, 2023
Revised manuscript not accepted
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Ice sheet models can help predict how Antarctica’s ice sheets respond to environmental change; such models benefit from comparison to geological data. Here, we use ice sheet model results, plus other data, to predict the erosion of Antarctic debris and trace its transport to where it is deposited on the ocean floor. This allows the results of ice sheet modelling to be directly and quantitively compared to real-world data, helping to reduce uncertainty regarding Antarctic sea level contribution.
James A. Smith, Louise Callard, Michael J. Bentley, Stewart S. R. Jamieson, Maria Luisa Sánchez-Montes, Timothy P. Lane, Jeremy M. Lloyd, Erin L. McClymont, Christopher M. Darvill, Brice R. Rea, Colm O'Cofaigh, Pauline Gulliver, Werner Ehrmann, Richard S. Jones, and David H. Roberts
The Cryosphere, 17, 1247–1270, https://doi.org/10.5194/tc-17-1247-2023, https://doi.org/10.5194/tc-17-1247-2023, 2023
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The Greenland Ice Sheet is melting at an accelerating rate. To understand the significance of these changes we reconstruct the history of one of its fringing ice shelves, known as 79° N ice shelf. We show that the ice shelf disappeared 8500 years ago, following a period of enhanced warming. An important implication of our study is that 79° N ice shelf is susceptible to collapse when atmospheric and ocean temperatures are ~2°C warmer than present, which could occur by the middle of this century.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
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The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
Matthew Chadwick, Claire S. Allen, Louise C. Sime, Xavier Crosta, and Claus-Dieter Hillenbrand
Clim. Past, 18, 129–146, https://doi.org/10.5194/cp-18-129-2022, https://doi.org/10.5194/cp-18-129-2022, 2022
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Algae preserved in marine sediments have allowed us to reconstruct how much winter sea ice was present around Antarctica during a past time period (130 000 years ago) when the climate was warmer than today. The patterns of sea-ice increase and decrease vary between different parts of the Southern Ocean. The Pacific sector has a largely stable sea-ice extent, whereas the amount of sea ice in the Atlantic sector is much more variable with bigger decreases and increases than other regions.
Nele Lamping, Juliane Müller, Jens Hefter, Gesine Mollenhauer, Christian Haas, Xiaoxu Shi, Maria-Elena Vorrath, Gerrit Lohmann, and Claus-Dieter Hillenbrand
Clim. Past, 17, 2305–2326, https://doi.org/10.5194/cp-17-2305-2021, https://doi.org/10.5194/cp-17-2305-2021, 2021
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We analysed biomarker concentrations on surface sediment samples from the Antarctic continental margin. Highly branched isoprenoids and GDGTs are used for reconstructing recent sea-ice distribution patterns and ocean temperatures respectively. We compared our biomarker-based results with data obtained from satellite observations and estimated from a numerical model and find reasonable agreements. Further, we address caveats and provide recommendations for future investigations.
Charlotte L. Spencer-Jones, Erin L. McClymont, Nicole J. Bale, Ellen C. Hopmans, Stefan Schouten, Juliane Müller, E. Povl Abrahamsen, Claire Allen, Torsten Bickert, Claus-Dieter Hillenbrand, Elaine Mawbey, Victoria Peck, Aleksandra Svalova, and James A. Smith
Biogeosciences, 18, 3485–3504, https://doi.org/10.5194/bg-18-3485-2021, https://doi.org/10.5194/bg-18-3485-2021, 2021
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Long-term ocean temperature records are needed to fully understand the impact of West Antarctic Ice Sheet collapse. Glycerol dialkyl glycerol tetraethers (GDGTs) are powerful tools for reconstructing ocean temperature but can be difficult to apply to the Southern Ocean. Our results show active GDGT synthesis in relatively warm depths of the ocean. This research improves the application of GDGT palaeoceanographic proxies in the Southern Ocean.
Chris S. M. Turney, Richard T. Jones, Nicholas P. McKay, Erik van Sebille, Zoë A. Thomas, Claus-Dieter Hillenbrand, and Christopher J. Fogwill
Earth Syst. Sci. Data, 12, 3341–3356, https://doi.org/10.5194/essd-12-3341-2020, https://doi.org/10.5194/essd-12-3341-2020, 2020
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The Last Interglacial (129–116 ka) experienced global temperatures and sea levels higher than today. The direct contribution of warmer conditions to global sea level (thermosteric) are uncertain. We report a global network of sea surface temperatures. We find mean global annual temperature anomalies of 0.2 ± 0.1˚C and an early maximum peak of 0.9 ± 0.1˚C. Our reconstruction suggests warmer waters contributed on average 0.08 ± 0.1 m and a peak contribution of 0.39 ± 0.1 m to global sea level.
Tom A. Jordan, David Porter, Kirsty Tinto, Romain Millan, Atsuhiro Muto, Kelly Hogan, Robert D. Larter, Alastair G. C. Graham, and John D. Paden
The Cryosphere, 14, 2869–2882, https://doi.org/10.5194/tc-14-2869-2020, https://doi.org/10.5194/tc-14-2869-2020, 2020
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Linking ocean and ice sheet processes allows prediction of sea level change. Ice shelves form a floating buffer between the ice–ocean systems, but the water depth beneath is often a mystery, leaving a critical blind spot in our understanding of how these systems interact. Here, we use airborne measurements of gravity to reveal the bathymetry under the ice shelves flanking the rapidly changing Thwaites Glacier and adjacent glacier systems, providing new insights and data for future models.
Kelly A. Hogan, Robert D. Larter, Alastair G. C. Graham, Robert Arthern, James D. Kirkham, Rebecca L. Totten, Tom A. Jordan, Rachel Clark, Victoria Fitzgerald, Anna K. Wåhlin, John B. Anderson, Claus-Dieter Hillenbrand, Frank O. Nitsche, Lauren Simkins, James A. Smith, Karsten Gohl, Jan Erik Arndt, Jongkuk Hong, and Julia Wellner
The Cryosphere, 14, 2883–2908, https://doi.org/10.5194/tc-14-2883-2020, https://doi.org/10.5194/tc-14-2883-2020, 2020
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The sea-floor geometry around the rapidly changing Thwaites Glacier is a key control on warm ocean waters reaching the ice shelf and grounding zone beyond. This area was previously unsurveyed due to icebergs and sea-ice cover. The International Thwaites Glacier Collaboration mapped this area for the first time in 2019. The data reveal troughs over 1200 m deep and, as this region is thought to have only ungrounded recently, provide key insights into the morphology beneath the grounded ice sheet.
Jan Erik Arndt, Robert D. Larter, Claus-Dieter Hillenbrand, Simon H. Sørli, Matthias Forwick, James A. Smith, and Lukas Wacker
The Cryosphere, 14, 2115–2135, https://doi.org/10.5194/tc-14-2115-2020, https://doi.org/10.5194/tc-14-2115-2020, 2020
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We interpret landforms on the seabed and investigate sediment cores to improve our understanding of the past ice sheet development in this poorly understood part of Antarctica. Recent crack development of the Brunt ice shelf has raised concerns about its stability and the security of the British research station Halley. We describe ramp-shaped bedforms that likely represent ice shelf grounding and stabilization locations of the past that may reflect an analogue to the process going on now.
Kelly A. Hogan, Martin Jakobsson, Larry Mayer, Brendan T. Reilly, Anne E. Jennings, Joseph S. Stoner, Tove Nielsen, Katrine J. Andresen, Egon Nørmark, Katrien A. Heirman, Elina Kamla, Kevin Jerram, Christian Stranne, and Alan Mix
The Cryosphere, 14, 261–286, https://doi.org/10.5194/tc-14-261-2020, https://doi.org/10.5194/tc-14-261-2020, 2020
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Glacial sediments in fjords hold a key record of environmental and ice dynamic changes during ice retreat. Here we use a comprehensive geophysical survey from the Petermann Fjord system in NW Greenland to map these sediments, identify depositional processes and calculate glacial erosion rates for the retreating palaeo-Petermann ice stream. Ice streaming is the dominant control on glacial erosion rates which vary by an order of magnitude during deglaciation and are in line with modern rates.
James D. Kirkham, Kelly A. Hogan, Robert D. Larter, Neil S. Arnold, Frank O. Nitsche, Nicholas R. Golledge, and Julian A. Dowdeswell
The Cryosphere, 13, 1959–1981, https://doi.org/10.5194/tc-13-1959-2019, https://doi.org/10.5194/tc-13-1959-2019, 2019
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A series of huge (500 m wide, 50 m deep) channels were eroded by water flowing beneath Pine Island and Thwaites glaciers in the past. The channels are similar to canyon systems produced by floods of meltwater released beneath the Antarctic Ice Sheet millions of years ago. The spatial extent of the channels formed beneath Pine Island and Thwaites glaciers demonstrates significant quantities of water, possibly discharged from trapped subglacial lakes, flowed beneath these glaciers in the past.
Robert D. Larter, Kelly A. Hogan, Claus-Dieter Hillenbrand, James A. Smith, Christine L. Batchelor, Matthieu Cartigny, Alex J. Tate, James D. Kirkham, Zoë A. Roseby, Gerhard Kuhn, Alastair G. C. Graham, and Julian A. Dowdeswell
The Cryosphere, 13, 1583–1596, https://doi.org/10.5194/tc-13-1583-2019, https://doi.org/10.5194/tc-13-1583-2019, 2019
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We present high-resolution bathymetry data that provide the most complete and detailed imagery of any Antarctic palaeo-ice stream bed. These data show how subglacial water was delivered to and influenced the dynamic behaviour of the ice stream. Our observations provide insights relevant to understanding the behaviour of modern ice streams and forecasting the contributions that they will make to future sea level rise.
Dominic A. Hodgson, Tom A. Jordan, Jan De Rydt, Peter T. Fretwell, Samuel A. Seddon, David Becker, Kelly A. Hogan, Andrew M. Smith, and David G. Vaughan
The Cryosphere, 13, 545–556, https://doi.org/10.5194/tc-13-545-2019, https://doi.org/10.5194/tc-13-545-2019, 2019
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The Brunt Ice Shelf in Antarctica is home to Halley VIa, the latest in a series of six British research stations that have occupied the ice shelf since 1956. A recent rapid growth of rifts in the Brunt Ice Shelf signals the onset of its largest calving event since records began. Here we consider whether this calving event will lead to a new steady state for the ice shelf or an unpinning from the bed, which could predispose it to accelerated flow or collapse.
Dominic A. Hodgson, Kelly Hogan, James M. Smith, James A. Smith, Claus-Dieter Hillenbrand, Alastair G. C. Graham, Peter Fretwell, Claire Allen, Vicky Peck, Jan-Erik Arndt, Boris Dorschel, Christian Hübscher, Andrew M. Smith, and Robert Larter
The Cryosphere, 12, 2383–2399, https://doi.org/10.5194/tc-12-2383-2018, https://doi.org/10.5194/tc-12-2383-2018, 2018
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We studied the Coats Land ice margin, Antarctica, providing a multi-disciplinary geophysical assessment of the ice sheet configuration through its last advance and retreat; a description of the physical constraints on the stability of the past and present ice and future margin based on its submarine geomorphology and ice-sheet geometry; and evidence that once detached from the bed, the ice shelves in this region were predisposed to rapid retreat back to coastal grounding lines.
Jan Erik Arndt, Robert D. Larter, Peter Friedl, Karsten Gohl, Kathrin Höppner, and the Science Team of Expedition PS104
The Cryosphere, 12, 2039–2050, https://doi.org/10.5194/tc-12-2039-2018, https://doi.org/10.5194/tc-12-2039-2018, 2018
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The calving line location of the Pine Island Glacier did not show any trend within the last 70 years until calving in 2015 led to unprecedented retreat. In February 2017 we accessed this previously ice-shelf-covered area with RV Polarstern and mapped the sea-floor topography for the first time. Satellite imagery of the last decades show how the newly mapped shoals affected the ice shelf development and highlights that sea-floor topography is an important factor in initiating calving events.
Yuribia P. Munoz and Julia S. Wellner
The Cryosphere, 12, 205–225, https://doi.org/10.5194/tc-12-205-2018, https://doi.org/10.5194/tc-12-205-2018, 2018
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We mapped submarine landforms in western Antarctic Peninsula bays. These landforms were formed by flowing ice and provide insight into the local controls on glacial ice advance and retreat. We combined data from various cruises to create seafloor maps. We conclude that the number of landforms found in the bays scales to the size of the bay, narrower bays tend to stabilize ice flow, and meltwater channels are abundant, and we hypothesize a recent glacial advance, likely the Little Ice Age.
C. Lavoie, E. W. Domack, E. C. Pettit, T. A. Scambos, R. D. Larter, H.-W. Schenke, K. C. Yoo, J. Gutt, J. Wellner, M. Canals, J. B. Anderson, and D. Amblas
The Cryosphere, 9, 613–629, https://doi.org/10.5194/tc-9-613-2015, https://doi.org/10.5194/tc-9-613-2015, 2015
J. S. Wellner
Sci. Dril., 18, 11–11, https://doi.org/10.5194/sd-18-11-2014, https://doi.org/10.5194/sd-18-11-2014, 2014
F. O. Nitsche, K. Gohl, R. D. Larter, C.-D. Hillenbrand, G. Kuhn, J. A. Smith, S. Jacobs, J. B. Anderson, and M. Jakobsson
The Cryosphere, 7, 249–262, https://doi.org/10.5194/tc-7-249-2013, https://doi.org/10.5194/tc-7-249-2013, 2013
Related subject area
Benthic foraminifera
Change in biodiversity and abundance of benthic foraminifera with distance from the Rainbow hydrothermal vent field, Mid-Atlantic Ridge
Analysis of the types of Reinholdella, an important Jurassic foraminiferal genus
Leisure boat harbours, hidden alien species, and pollution: a case study of Hinsholmskilen harbour (Gothenburg, Sweden)
Miocene Climatic Optimum and Middle Miocene Climate Transition: a foraminiferal record from the central Ross Sea, Antarctica
Distribution of two notodendrodid foraminiferal congeners in McMurdo Sound, Antarctica: an example of extreme regional endemism?
Benthic foraminifers in coastal habitats of Ras Mohamed Nature Reserve, southern Sinai, Red Sea, Egypt
Late Miocene to Early Pliocene benthic foraminifera from the Tasman Sea (International Ocean Discovery Program Site U1506)
Triassic and Jurassic possible planktonic foraminifera and the assemblages recovered from the Ogrodzieniec Glauconitic Marls Formation (uppermost Callovian and lowermost Oxfordian, Jurassic) of the Polish Basin
Benthic foraminiferal patchiness – revisited
Agglutinated foraminifera from the Turonian–Coniacian boundary interval in Europe – paleoenvironmental remarks and stratigraphy
Meghalayan environmental evolution of the Thapsus coast (Tunisia) as inferred from sedimentological and micropaleontological proxies
Biometry and taxonomy of Adriatic Ammonia species from Bellaria–Igea Marina (Italy)
Biogeographic distribution of three phylotypes (T1, T2 and T6) of Ammonia (foraminifera, Rhizaria) around Great Britain: new insights from combined molecular and morphological recognition
Comparative analysis of six common foraminiferal species of the genera Cassidulina, Paracassidulina, and Islandiella from the Arctic–North Atlantic domain
Microfossil assemblages and geochemistry for interpreting the incidence of the Jenkyns Event (early Toarcian) in the south-eastern Iberian Palaeomargin (External Subbetic, SE Spain)
Micropalaeontology, biostratigraphy, and depositional setting of the mid-Cretaceous Derdere Formation at Derik, Mardin, south-eastern Turkey
Latest Oligocene to earliest Pliocene deep-sea benthic foraminifera from Ocean Drilling Program (ODP) Sites 752, 1168 and 1139, southern Indian Ocean
Benthic foraminifera indicate Glacial North Pacific Intermediate Water and reduced primary productivity over Bowers Ridge, Bering Sea, since the Mid-Brunhes Transition
Reconstructing the Christian Malford ecosystem in the Oxford Clay Formation (Callovian, Jurassic) of Wiltshire: exceptional preservation, taphonomy, burial and compaction
Benthic foraminiferal assemblages and test accumulation in coastal microhabitats on San Salvador, Bahamas
Assessing proxy signatures of temperature, salinity, and hypoxia in the Baltic Sea through foraminifera-based geochemistry and faunal assemblages
New species of Mesozoic benthic foraminifera from the former British Petroleum micropalaeontology collection
Monitoring benthic foraminiferal dynamics at Bottsand coastal lagoon (western Baltic Sea)
Paleocene orthophragminids from the Lakadong Limestone, Mawmluh Quarry section, Meghalaya (Shillong, NE India): implications for the regional geology and paleobiogeography
Larger foraminifera of the Devil's Den and Blue Hole sinkholes, Florida
Assessing the composition of fragmented agglutinated foraminiferal assemblages in ancient sediments: comparison of counting and area-based methods in Famennian samples (Late Devonian)
Hannah Krüger, Gerhard Schmiedl, Zvi Steiner, Zhouling Zhang, Eric P. Achterberg, and Nicolaas Glock
J. Micropalaeontol., 44, 193–211, https://doi.org/10.5194/jm-44-193-2025, https://doi.org/10.5194/jm-44-193-2025, 2025
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The biodiversity and abundance of benthic foraminifera tend to increase with distance within a transect from the Rainbow hydrothermal vent field. Miliolids dominate closer to the vents and may be better adapted to the potentially hydrothermal conditions than hyaline and agglutinated species. The reason for this remains unclear, but there are indications that elevated trace-metal concentrations in the porewater and intrusion of acidic hydrothermal fluids could have an influence on the foraminifera.
Marjorie Apthorpe
J. Micropalaeontol., 44, 169–191, https://doi.org/10.5194/jm-44-169-2025, https://doi.org/10.5194/jm-44-169-2025, 2025
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The holotype specimen of the type species of the important Jurassic foraminiferal genus Reinholdella has been photographed in the environmental scanning electron microscope (ESEMTM) and redescribed. The confusion surrounding the taxonomy of this genus is described in detail, and species involved in this confusion are described and photographically illustrated. The features of the genus include a single aperture. The 29 species presently included in this genus require re-assessment.
Irina Polovodova Asteman, Emilie Jaffré, Agata Olejnik, Maria Holzmann, Mary McGann, Kjell Nordberg, Jean-Charles Pavard, Delia Rösel, and Magali Schweizer
J. Micropalaeontol., 44, 119–143, https://doi.org/10.5194/jm-44-119-2025, https://doi.org/10.5194/jm-44-119-2025, 2025
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Small boat harbours are suggested to cause pollution and alien species introductions. Here we analysed surface sediments in Hinsholmskilen harbour (Sweden) for benthic foraminifera and potentially toxic elements. Molecular and morphological analyses of foraminifera show the presence of two alien species, Trochammina hadai and Ammonia confertitesta, whilst pollution is mostly low for Cd, Co, Ni, and Pb. In contrast, As, Zn, Cu, Hg, and Cr have high levels due to the use of these elements in boat paints.
Samantha E. Bombard, R. Mark Leckie, Imogen M. Browne, Amelia E. Shevenell, Robert M. McKay, David M. Harwood, and the IODP Expedition 374 Scientists
J. Micropalaeontol., 43, 383–421, https://doi.org/10.5194/jm-43-383-2024, https://doi.org/10.5194/jm-43-383-2024, 2024
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The Ross Sea record of the Miocene Climatic Optimum (~16.9–14.7 Ma) and the Middle Miocene Climate Transition (~14.7–13.8 Ma) can provide critical insights into the Antarctic ocean–cryosphere system during an ancient time of extreme warmth and subsequent cooling. Benthic foraminifera inform us about water masses, currents, and glacial conditions in the Ross Sea, and planktic foram invaders can inform us of when warm waters melted the Antarctic Ice Sheet in the past.
Andrea Habura, Stephen P. Alexander, Steven D. Hanes, Andrew J. Gooday, Jan Pawlowski, and Samuel S. Bowser
J. Micropalaeontol., 43, 337–347, https://doi.org/10.5194/jm-43-337-2024, https://doi.org/10.5194/jm-43-337-2024, 2024
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Two species of giant, single-celled "trees” inhabit the seafloor in McMurdo Sound, Antarctica. These unicellular creatures are large enough to be seen and counted by scuba divers. We found that one of the tree species is widely spread, whereas the other inhabits only a small region on the western side of the sound. These types of unicellular trees have not been found elsewhere in the world ocean and are particularly vulnerable to the effects of climate change.
Ahmed M. BadrElDin and Pamela Hallock
J. Micropalaeontol., 43, 239–267, https://doi.org/10.5194/jm-43-239-2024, https://doi.org/10.5194/jm-43-239-2024, 2024
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The Red Sea hosts exceptionally diverse marine environments despite elevated salinities. Distributions of benthic foraminifers were used to assess the ecological status of coral reef environments in the Ras Mohamed Nature Reserve, south Sinai. Sediment samples collected in mangrove, shallow-lagoon, and coral reef habitats yielded 95 foraminiferal species. Six species, five hosting algal symbionts, made up ~70 % of the specimens examined, indicating water quality suitable for reef accretion.
Maria Elena Gastaldello, Claudia Agnini, and Laia Alegret
J. Micropalaeontol., 43, 1–35, https://doi.org/10.5194/jm-43-1-2024, https://doi.org/10.5194/jm-43-1-2024, 2024
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This paper examines benthic foraminifera, single-celled organisms, at Integrated Ocean Drilling Program Site U1506 in the Tasman Sea from the Late Miocene to the Early Pliocene (between 7.4 to 4.5 million years ago). We described and illustrated the 36 most common species; analysed the past ocean depth of the site; and investigated the environmental conditions at the seafloor during the Biogenic Bloom phenomenon, a global phase of high marine primary productivity.
Malcolm B. Hart, Holger Gebhardt, Eiichi Setoyama, Christopher W. Smart, and Jarosław Tyszka
J. Micropalaeontol., 42, 277–290, https://doi.org/10.5194/jm-42-277-2023, https://doi.org/10.5194/jm-42-277-2023, 2023
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<p>In the 1960s-1970s some species of Triassic foraminifera were described as having a planktic mode of life. This was questioned and Malcolm Hart studied the material in Vienna, taking some to London for SEM imaging. Samples collected from Poland are compared to these images and the suggested planktic mode of life discussed. Foraminifera collected in Ogrodzieniec are glauconitic steinkerns with no test material present and none of the diagnostic features needed to determine "new" species.</p>
Joachim Schönfeld, Nicolaas Glock, Irina Polovodova Asteman, Alexandra-Sophie Roy, Marié Warren, Julia Weissenbach, and Julia Wukovits
J. Micropalaeontol., 42, 171–192, https://doi.org/10.5194/jm-42-171-2023, https://doi.org/10.5194/jm-42-171-2023, 2023
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Benthic organisms show aggregated distributions due to the spatial heterogeneity of niches or food. We analysed the distribution of Globobulimina turgida in the Gullmar Fjord, Sweden, with a data–model approach. The population densities did not show any underlying spatial structure but a random log-normal distribution. A temporal data series from the same site depicted two cohorts of samples with high or low densities, which represent hypoxic or well-ventilated conditions in the fjord.
Richard M. Besen, Kathleen Schindler, Andrew S. Gale, and Ulrich Struck
J. Micropalaeontol., 42, 117–146, https://doi.org/10.5194/jm-42-117-2023, https://doi.org/10.5194/jm-42-117-2023, 2023
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Turonian–Coniacian agglutinated foraminiferal assemblages from calcareous deposits from the temperate European shelf realm were studied. Acmes of agglutinated foraminifera correlate between different sections and can be used for paleoenvironmental analysis expressing inter-regional changes. Agglutinated foraminiferal morphogroups display a gradual shift from Turonian oligotrophic environments towards more mesotrophic conditions in the latest Turonian and Coniacian.
Mohamed Kamoun, Martin R. Langer, Chahira Zaibi, and Mohamed Ben Youssef
J. Micropalaeontol., 41, 129–147, https://doi.org/10.5194/jm-41-129-2022, https://doi.org/10.5194/jm-41-129-2022, 2022
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Sedimentology and micropaleontology analyses provide the dynamic processes that shaped the environmental evolution of the Thapsus coastline (Tunisia) including its lagoon and Roman harbor. The highlights are paleoenvironmental change records from the coast of Thapsus for the last 4000 years, benthic foraminiferal biota recording the dynamic coastal processes, two transgressive events being recognized, and a presented model for the paleoenvironmental evolution.
Joachim Schönfeld, Valentina Beccari, Sarina Schmidt, and Silvia Spezzaferri
J. Micropalaeontol., 40, 195–223, https://doi.org/10.5194/jm-40-195-2021, https://doi.org/10.5194/jm-40-195-2021, 2021
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Ammonia beccarii was described from Rimini Beach in 1758. This taxon has often been mistaken with other species in the past. Recent studies assessed the biometry of Ammonia species and integrated it with genetic data but relied on a few large and dead specimens only. In a comprehensive approach, we assessed the whole living Ammonia assemblage near the type locality of A. beccarii and identified parameters which are robust and facilitate a secure species identification.
Julien Richirt, Magali Schweizer, Aurélia Mouret, Sophie Quinchard, Salha A. Saad, Vincent M. P. Bouchet, Christopher M. Wade, and Frans J. Jorissen
J. Micropalaeontol., 40, 61–74, https://doi.org/10.5194/jm-40-61-2021, https://doi.org/10.5194/jm-40-61-2021, 2021
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The study presents (1) a validation of a method which was previously published allowing us to recognize different Ammonia phylotypes (T1, T2 and T6) based only on their morphology and (2) a refined biogeographical distribution presented here supporting the putatively invasive character of phylotype T6. Results suggest that phylotype T6 is currently spreading out and supplanting autochthonous phylotypes T1 and T2 along the coastlines of the British Isles and northern France.
Alix G. Cage, Anna J. Pieńkowski, Anne Jennings, Karen Luise Knudsen, and Marit-Solveig Seidenkrantz
J. Micropalaeontol., 40, 37–60, https://doi.org/10.5194/jm-40-37-2021, https://doi.org/10.5194/jm-40-37-2021, 2021
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Morphologically similar benthic foraminifera taxa are difficult to separate, resulting in incorrect identifications, complications understanding species-specific ecological preferences, and flawed reconstructions of past environments. Here we provide descriptions and illustrated guidelines on how to separate some key Arctic–North Atlantic species to circumvent taxonomic confusion, improve understanding of ecological affinities, and work towards more accurate palaeoenvironmental reconstructions.
Matías Reolid
J. Micropalaeontol., 39, 233–258, https://doi.org/10.5194/jm-39-233-2020, https://doi.org/10.5194/jm-39-233-2020, 2020
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During the early Toarcian (Jurassic, 180 Ma) a hyperthermal event, the Jenkyns Event, occurred, affecting the oxygenation of the sea bottom. The integrated study of foraminiferal and ostracod assemblages with geochemical proxies allows us to interpret the incidence of this event in the Western Tethys, more exactly in the South Iberian Palaeomargin. Diminution of diversity, changes in abundance, and opportunist vs. specialist are coincident with the event.
Michael D. Simmons, Vicent Vicedo, İsmail Ö. Yılmaz, İzzet Hoşgör, Oğuz Mülayim, and Bilal Sarı
J. Micropalaeontol., 39, 203–232, https://doi.org/10.5194/jm-39-203-2020, https://doi.org/10.5194/jm-39-203-2020, 2020
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The microfossils from a Cretaceous outcrop in southern Turkey are described and used to interpret the age of the rocks and their depositional setting and how sea level has changed. These results are compared both locally and regionally, identifying broad correspondence with regional sea level events. A new species of microfossil is described, confirming that many microfossils of Arabia are localised in their distribution.
Dana Ridha, Ian Boomer, and Kirsty M. Edgar
J. Micropalaeontol., 38, 189–229, https://doi.org/10.5194/jm-38-189-2019, https://doi.org/10.5194/jm-38-189-2019, 2019
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This paper records the spatial and temporal distribution of deep-sea benthic microfossils (Foraminifera, single-celled organisms) from the latest Oligocene to earliest Pliocene (about 28 to 4 million years ago) from Ocean Drilling Program cores in the southern Indian Ocean. Key taxa are illustrated and their stratigraphic distribution is presented as they respond to a period of marked global climatic changes, with a pronounced warm period in the mid-Miocene followed by subsequent cooling.
Sev Kender, Adeyinka Aturamu, Jan Zalasiewicz, Michael A. Kaminski, and Mark Williams
J. Micropalaeontol., 38, 177–187, https://doi.org/10.5194/jm-38-177-2019, https://doi.org/10.5194/jm-38-177-2019, 2019
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The Mid-Brunhes Transition saw an enigmatic shift towards increased glacial temperature variations about 400 kyr ago. High-latitude Southern Ocean stratification may have been a causal factor, but little is known of the changes to the high-latitude Bering Sea. We generated benthic foraminiferal assemblage data and are the first to document a glacial decrease in episodic primary productivity since the Mid-Brunhes Transition, signifying possible reductions in sea ice summer stratification.
Malcolm B. Hart, Kevin N. Page, Gregory D. Price, and Christopher W. Smart
J. Micropalaeontol., 38, 133–142, https://doi.org/10.5194/jm-38-133-2019, https://doi.org/10.5194/jm-38-133-2019, 2019
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The use of micropalaeontological samples from mudstone successions that have suffered de-watering and compaction means that subtle, lamina-thick, changes in assemblages may be lost when samples are processed that are 1–2 cm thick. As most micropalaeontological samples are often 2–5 cm thick, one must be then cautious of interpretations based on such short-duration changes. This work is part of an integrated study of the Christian Malford lagerstätten that has resulted in a number of papers.
Andrea Fischel, Marit-Solveig Seidenkrantz, and Bent Vad Odgaard
J. Micropalaeontol., 37, 499–518, https://doi.org/10.5194/jm-37-499-2018, https://doi.org/10.5194/jm-37-499-2018, 2018
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Benthic foraminifera often colonize marine underwater vegetation in tropical regions. We studied these so-called epiphytic foraminifera in a shallow bay in the Bahamas. Here the foraminifera differed between types of vegetation, but sedimentological processes seem to be the main controller of the dead foraminifera in the sediment. This indicates that in carbonate platform regions, epiphytic foraminifera should only be used cautiously as direct indicators of past in situ marine vegetation.
Jeroen Groeneveld, Helena L. Filipsson, William E. N. Austin, Kate Darling, David McCarthy, Nadine B. Quintana Krupinski, Clare Bird, and Magali Schweizer
J. Micropalaeontol., 37, 403–429, https://doi.org/10.5194/jm-37-403-2018, https://doi.org/10.5194/jm-37-403-2018, 2018
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Current climate and environmental changes strongly affect shallow marine and coastal areas like the Baltic Sea. The combination of foraminiferal geochemistry and environmental parameters demonstrates that in a highly variable setting like the Baltic Sea, it is possible to separate different environmental impacts on the foraminiferal assemblages and therefore use chemical factors to reconstruct how seawater temperature, salinity, and oxygen varied in the past and may vary in the future.
Lyndsey R. Fox, Stephen Stukins, Tom Hill, and Haydon W. Bailey
J. Micropalaeontol., 37, 395–401, https://doi.org/10.5194/jm-37-395-2018, https://doi.org/10.5194/jm-37-395-2018, 2018
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This paper describes five new Mesozoic deep-water benthic foraminifera from the former British Petroleum microfossil reference collections at the Natural History Museum, London.
Joachim Schönfeld
J. Micropalaeontol., 37, 383–393, https://doi.org/10.5194/jm-37-383-2018, https://doi.org/10.5194/jm-37-383-2018, 2018
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Benthic foraminifera from the Bottsand coastal lagoon, western Baltic Sea, have been monitored annually since 2003 and accompanied by hydrographic measurements since 2012. Elphidium incertum, a stenohaline species of the Baltic deep water fauna, colonised the lagoon in 2016, most likely during a period of salinities > 19 units and average temperatures of 18 °C in early autumn. The high salinities probably triggered their germination from a propagule bank in the lagoonal bottom sediment.
Ercan Özcan, Johannes Pignatti, Christer Pereira, Ali Osman Yücel, Katica Drobne, Filippo Barattolo, and Pratul Kumar Saraswati
J. Micropalaeontol., 37, 357–381, https://doi.org/10.5194/jm-37-357-2018, https://doi.org/10.5194/jm-37-357-2018, 2018
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We carried out a morphometric study of late Paleocene orthophragminids from the Mawmluh Quarry section in the Shillong Plateau, India. We recorded the occurrence of two species of Orbitoclypeus, whereas the other typical Tethyan genera Discocyclina is absent. We also identified the associated benthic foraminifera and algae. Shallow benthic zones (SBZ) 3 and 4 have been recognized in the section. The timing of transition from shallow marine to continental deposition is commented on.
Laura J. Cotton, Wolfgang Eder, and James Floyd
J. Micropalaeontol., 37, 347–356, https://doi.org/10.5194/jm-37-347-2018, https://doi.org/10.5194/jm-37-347-2018, 2018
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Shallow-water carbonate deposits rich in larger benthic foraminifera (LBF) are well-known from the Eocene of the Americas. However, there have been few recent LBF studies in this region. Here we present the LBF ranges from two previously unpublished sections from the Ocala limestone, Florida. The study indicates that the lower member of the Ocala limestone may be Bartonian rather than Priabonian in age, with implications for regional biostratigraphy.
Catherine Girard, Anne-Béatrice Dufour, Anne-Lise Charruault, and Sabrina Renaud
J. Micropalaeontol., 37, 87–95, https://doi.org/10.5194/jm-37-87-2018, https://doi.org/10.5194/jm-37-87-2018, 2018
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This study constitutes an attempt to analyze the variations in foraminiferal assemblages using the morphogroup approach in the Late Devonian. Our results show that both methods of estimating morphotype percentages, the traditional counting and the cumulated area methods, provide similar results, are highly correlated with each other, and provide similar relationships with paleoenvironmental proxies.
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Short summary
Thwaites Glacier's retreat is driven by warm ocean water melting its ice shelf. Seafloor-dwelling marine protists, benthic foraminifera, reflect their environment. Here, ice margins, oceanography, and sea ice cover control live foraminiferal populations. Including dead foraminifera in the analyses shows the calcareous test preservation's role in the assemblage make-up. Understanding these modern communities helps interpret past glacial retreat controls through foraminifera in sediment records.
Thwaites Glacier's retreat is driven by warm ocean water melting its ice shelf....
