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3. Practical guidelines and recent advances in the Itrax XRF core-scanning procedure

Author

Bloemsma, Menno, Croudace, Ian, Daly, J. Stephen, Edwards, Robin J., Francus, Pierre, Galloway, Jennifer M., Gregory, Braden R.B., Steven Huang, Jyh-Jaan, Jones, Anna F., Kylander, Malin, Löwemark, Ludvig, Luo, Yangbing, Maclachlan, Suzanne, Ohlendorf, Christian, Patterson, R. Timothy, Pearce, Christof, Profe, Jörn, Reinhardt, Eduard G., Stranne, Christian, Tjallingii, Rik, and Turner, Jonathan N.

Published
2019
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6. Holocene environmental and climate evolution of central west Patagonia as reconstructed from lacustrine sediments of Meseta Chile Chico (46.5° S, Chile).

Author

Franco, Carolina, Maldonado, Antonio, Ohlendorf, Christian, Gebhardt, A. Catalina, de Porras, María Eugenia, Nuevo-Delaunay, Amalia, Méndez, César, and Zolitschka, Bernd

Subjects
HOLOCENE Epoch, PRECIPITATION variability, WESTERLIES, SEDIMENTS, ICE caps, GLACIAL landforms, GLACIERS
Abstract

Holocene environmental changes in Patagonia were mostly shaped by fluctuating ice cover recession. Consequently, environmental reconstructions are largely based on discontinuous moraine chronologies from valley deposits. Here, we present a 3 m long continuous sediment record recovered from Laguna Meseta (LME), a lake located on Meseta Chile Chico. Its altitude and location relative to the North Patagonian Icefield provide a unique opportunity to reconstruct the glacial history and related environmental dynamics. Our radiocarbon chronology constrains sedimentation to the last ∼10000 years and provides a minimum age for postglacial ice-free lacustrine conditions, due to a westward retreat of the ice cap. Lacustrine productivity reached its maximum at the start of the lake phase and decreased afterwards. Between 5500 and 4600 cal yr BP, a major shift towards allochthonous sediment accumulation occurred, caused by an abrupt increase in clastic deposition from basaltic lithologies of the Meseta Chile Chico. This episode correlates with the precipitation-driven Mid-Holocene glacier advance of Patagonian glaciers and suggests that conditions were colder and/or wetter on Meseta Chile Chico at that time. After 4600 cal yr BP, these conditions continued to supply LME with clastic sediments until a stepped decrease around 900 cal yr BP. Thereupon, lacustrine productivity distinctly increased and stabilized around 300 cal yr BP. Our findings indicate that changes in sedimentation on Meseta Chile Chico were mainly controlled by regional variability in the precipitation. Furthermore, strong correlation between our records and available proxies for oscillations of the Southern Hemisphere Westerly Winds suggest a pronounced climatic control by this prominent wind system for central west Patagonia during the last 10 000 years. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Holocene environmental and climate evolution of Central West Patagonia as reconstructed from lacustrine sediments of Meseta Chile Chico (46.5º S, Chile).

Author

Franco, Carolina, Maldonado, Antonio, Ohlendorf, Christian, Gebhardt, A. Catalina, Porras, María Eugenia de, Nuevo-Delaunay, Amalia, Méndez, César, and Zolitschka, Bernd

Subjects
HOLOCENE Epoch, PRECIPITATION variability, WESTERLIES, SEDIMENTS, ICE caps, GLACIAL landforms, GLACIERS
Abstract

Holocene environmental changes in Patagonia were mostly shaped by unsteady ice-cover recession. Consequently, environmental reconstructions are largely based on discontinuous moraine chronologies from valley deposits. Here, we present a 3 m-long continuous sediment record recovered from Laguna Meseta (LME), a lake located on Meseta Chile Chico. Its altitude and location relative to the North Patagonian Icefield provide a unique opportunity to reconstruct the glacial history and the related environmental dynamics. Our radiocarbon chronology constrains sedimentation to the last ~10,000 years and provides a minimum age for postglacial ice-free lacustrine conditions due to a westward retreat of the ice cap. Lacustrine productivity reached its maximum at the start of sedimentation and decreased afterwards. Between 5,500 and 4,600 cal yr BP, a major shift towards allochthonous sediment accumulation occurred, caused by an abrupt increase in clastic deposition from basaltic lithologies of the Meseta Chile Chico. This episode correlates with the precipitation-driven mid-Holocene glacier advance of Patagonian glaciers and suggests that conditions were colder/wetter on the Meseta Chile Chico at that time. After 4,600 cal yr BP these conditions continued to supply LME with clastic sediments until a stepped decrease around 900 cal yr BP. Thereupon, lacustrine productivity distinctly increased and stabilized around 300 cal yr BP. Our findings indicate that environmental conditions on Meseta Chile Chico were mainly controlled by precipitation variability during regional oscillations of the Southern Hemisphere Westerly Winds over the last 10 ka. [ABSTRACT FROM AUTHOR]

Published
2023
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25. Book of Abstracts - vDEUQUA2021

Author

Abadi, Mehrdad, Abbasi, Hamidreza, Abd El-Raouf, Amr, Abdulkarim, Mubarak, Adolph, Marie-Luise, Aeschbach, Werner, Akçar, Naki, Amini, Hamideh, Andreev, Andrej, Anselmetti, Flavio S., Aumaître, Georges, Avendaño Villeda, Diana, Bartz, Melanie, Baumhauer, Roland, Bazarradnaa, Enkhtuya, Bebiolka, Anke, Behling, Hermann, Benkaddour, Abdelfattah, Binot, Franz, Birlo, Stella, Bittner, Lucas, Bliedtner, Marcel, Bolland, Alexander, Bork, Hans-Rudolf, Bouaziz, Moncef, Bourlès, Didier, Brauer, Achim, Breuer, Sonja, Bromm, Tobias, Buechi, Marius W., Burghardt, Diana, Busch, Robert, Caballero, Margarita, Carr, Andrew S., Chapkanski, Stoil, Christl, Marcus, Cosac, Marian, Dal Corso, Marta, Daniel, Thomas, Dar, Reyaz, Dave, Aditi Krishna, De Jonge, Cindy, Deplazes, Gaudenz, Dietze, Elisabeth, Dietze, Michael, Dietzel, Martin, Dreibrodt, Stefan, Drysdale, Russell, du Plessis, Nadia, Dubois, Nathalie, Duller, Geoff, Duttmann, Rainer, Duval, Mathieu, Döhlert-Albani, Norman, Egli, Markus, Einwögerer, Thomas, Elbracht, Jörg, Enters, Dirk, Enzel, Yehouda, Ertlen, Damien, Farkas, Beáta, Fattahi, Morteza, Faust, Dominik, Faybishenko, Boris, Feistmantl, Nina, Fernandez, Philippe, Ferrier, Catherine, Fiedler, Sabine, Fischer, Birgit, Fischer, Peter, Fitzsimmons, Kathryn, Fletcher, William, Frechen, Manfred, Fuchs, Margret C., Fuchs, Markus, Fuelling, Alexander, Fábián, Szabolcs, Fülling, Alexander, Garbe, Philipp, Gebhardt, Catalina, Gegg, Lukas, Geis, Anna-Lena, Geitner, Clemens, Ghanbarian, Behzad, Gianotti, Franco, Gil Romera, Graciela, Glaser, Bruno, Glückler, Ramesh, Gresina, Fruzsina, Grootes, Pieter Meiert, Guadelli, Aleta, Guadelli, Jean-Luc, Guérin, Guillaume, Haas, Jean Nicolas, Haberzettl, Torsten, Hambach, Ulrich, Hardt, Jacob, Hein, Michael, Heinrich, Hartmut, Heinrich, Susann, Herzschuh, Ulrike, Heydari, Maryam, Hildebrandt, Dominic, Hirschmann, Philip, Hofmann, Felix Martin, Hofmann, Robert, Hogrefe, Ines, Huang, Jyh-Jaan Steven, Hunt, Allen, Händel, Marc, Ivy-Ochs, Susan, Jary, Zdzisław, Jeanneret, Pilar, Jöris, Olaf, Kalicki, Tomasz, Kamleitner, Sarah, Karaschewski, Jasmin, Keddadouche, Karim, Kehl, Martin, Kern, Zoltán, Kertscher, Cathleen, Khatooni, Darvish, Khosravichenar, Azra, Kipfer, Rolf, Kirchner, André, Kirleis, Wiebke, Klaes, Björn, Knitter, Daniel, Kolb, Thomas, Konstantinovski Puntos, Cyryl, Kreienbrink, Frauke, Kreutzer, Sebastian, Kulongoski, Justin, Laag, Christian, Labahn, Jakob, Lachner, Johannes, Lak, Razyeh, Lamb, Henry F., Lampe, Reinhard, Lang, Jörg, Lange-Athinodorou, Eva, Lauer, Tobias, Leanni, Laetitia, Leblanc, Jean-Claude, Lee, An-Sheng, Lehmkuhl, Frank, Lempe, Bernhard, Lerch, Marcel, Liou, Sofia Ya Hsuan, Lisa, Lenka, Liu, Zuorui, Lomax, Johanna, Lorenz, Sebastian, Lozano García, Socorro, Madarász, Balázs, Madritsch, Herfried, Maier, Andreas, Mangelsdorf, Kai, Markovic, Slobodan, Martinez Abarca, Luis Rodrigo, Marx, Samuel, May, Jan-Hendrik, Mayr, Christoph, Meister, Julia, Merchel, Silke, Meszner, Sascha, Meyer, Juliane, Mikdad, Abdeslam, Milevski, Ivica, Mir, Jehangeer, Mischke, Steffen, Mohammadi, Ali, Monegato, Giovanni, Moreiras, Stella, Mueller, Daniela, Muratoreanu, George, Müller, Daniela, Müller, Johannes, Nadeau, Marie-Josée, Nett, Janina, Neugebauer, Ina, Ng, Jessica, Nill, Leon, Nir, Nadav, Ohlendorf, Christian, Opp, Christian, Orgeira, Maria, Ortega Guerrero, Beatriz, Pasda, Clemens, Pasda, Kerstin, Penkman, Kirsty, Peric, Zoran, Pichat, Sylvain, Piller, Werner, Polgar, Irene, Prendergast, Amy, Preusser, Frank, Prud'homme, Charlotte, Pötter, Stephan, Quick, Lynne J., Rambeau, Claire, Reichert, Markus, Reimann, Tony, Reiss, Lilian, Roettig, Christopher-Bastian, Rolf, Christian, Russell, James, Ruszkiczay-Rüdiger, Zsófia, Ryzner, Kamila, Sahakyan, Lilit, Salazar, Gary, Salomon, Ferréol, Sardar Abadi, Mehrdad, Sarı, Selma, Scardia, Giancarlo, Schiestl, Robert, Schimmelpfennig, Irene, Schirmer, Wolfgang, Schmidt, Christoph, Schmidt, Johannes, Schmitt, Laurent, Schneider, Birgit, Schulte, Philipp, Schulze, Tabea, Schunke, Torsten, Schwab, Markus J., Schwahn, Lea, Schwamborn, Georg, Schwark, Lorenz, Schäfer, Dieter, Schütt, Brigitta, Seltzer, Alan, Selzer, Johnnes, Severinghaus, Jeffrey, Shah, Rayees, Simon, Ulrich, Sirakov, Nikolay, Sirakova, Svoboda, Sontag-González, Mariana, Sprafke, Tobias, Stahlschmidt, Mareike, Stauber, Theresa, Steier, Peter, Steiner, Martin, Stojakowits, Philipp, Strobel, Paul, Stroessner, Kathrin, Struck, Julian, Stute, Martin, Stutzriemer, Marika, Stäuble, Harald, Szidat, Sönke, Taneva, Stanimira, Tanner, David, ASTER, Team, Temovski, Marjan, Tinapp, Christian, Tjallingii, Rik, Trappe, Julian, Tylmann, Wojciech, Ulfers, Arne, Ullmann, Tobias, Urban, Brigitte, van Meer, Mike, Varga, György, Veres, Daniel, Verstraeten, Gert, Videiko, Michail, Vinnepand, Mathias, Vockenhuber, Christof, Vogel, Hendrik, Voigt, Silke, von Suchodoletz, Hans, Vött, Andreas, Weiß, Marcel, Werther, Lukas, Wolf, Daniel, Wonik, Thomas, Wrozyna, Claudia, Wunderlich, Tina, Zech, Michael, Zech, Roland, Zeeden, Christian, Zielhofer, Christoph, Zolitschka, Bernd, Zöller, Ludwig, Żurek, Krzysztof, von Suchodoletz, Hans, Dietze, Elisabeth, Dietze, Michael, Meister, Julia, Wrozyna, Claudia, Zeeden, Christian, Kreutzer, Sebastian, and Hildebrandt, Dominic

Subjects
Quaternary, Conference abstracts, Geoscience
Abstract

Collection of conference abstracts presented at the vDEUQUA2021 (2021-09-30 to 2021-09-01), the virtual meeting of the German Quaternary Association (DEUQUA).

Published
2021
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32. First evidence from Lake Melville, Canada: Subglacial lake sediments underneath the Laurentide Ice Sheet?

Author

Kowalski , Sophie, Ohlendorf , Christian, Gebhardt , Andrea Catalina, and Matthiessen , Jens

Abstract

The fjord-type Lake Melville is located in Labrador, Eastern Canada, as part of the Hamilton Inlet System. It is mainly characterised by riverine freshwater influx into its western end and intrusion of saline water from the Labrador Sea through the shallow Rigolet Narrows. Previous studies assumed that the retreating Laurentide Ice Sheet (LIS) caused the deposition of a typical glacial sediment sequence when its margin reached Lake Melville between 10,000 to 8,000 years ago (King, 1985; Syvitski and Lee, 1997). However, as suggested for other sites (e.g. Great Slave Lake; Christoffersen et al., 2008), the up to 400 m thick sediment package might contain pre-deglacial sediment because Lake Melville potentially persisted as a subglacial lake underneath the LIS. Initial measurements and lithological investigations on two selected sediment cores (~14 m and 16 m) recovered during expedition MSM84 (2019) indicate a significant change in lithology and selected sediment-physical parameters within the lowermost two meters. First 14C-dates of gastropod and bivalve remains resulted in a preliminary age model with an extrapolated basal age of ~11.6 ka cal BP, but hence pre-dating the local deglaciation. In accordance with sediment echosounder data, microscopic investigations and first XRF analysis, we assume that these initial findings point at sediment deposition in a subglacial lake environment. In a next step, we aim at significantly improving the age model by considering more 14C-samples from various sediment cores as well as conducting further multi-proxy analyses to test our hypothesis.

Published
2021
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33. Deposition of Subglacial Lake Sediments underneath the Laurentide Ice Sheet? – Sediment Cores from Lake Melville, Canada, provide first Evidence

Author

Kowalski, Sophie, Ohlendorf, Christian, Matthiessen, Jens, and Gebhardt, Andrea Catalina

Abstract

Lake Melville is a fjord-type lake located in Labrador, Eastern Canada, as part of the Hamilton Inlet System. It is significantly characterised by its eastern connection to the Labrador Sea through a shallow sill at the entrance to the Rigolet Narrows. In contrast, the western part of the lake receives freshwater input from several major rivers. Previous studies assumed that Lake Melville was fully excavated by the Laurentide Ice Sheet (LIS) during the last glacial. Thus, the retreat of the ice mass within the area from ~10,000 to 8,000 years ago caused the deposition of a typical glacial sediment sequence in the lake (King, 1985; Syvitski and Lee, 1997). However, up to 400 m of sediment have been accumulated in the deepest basins of Lake Melville. Since this shows a resemblance to other Canadian sites (e.g. Great Slave Lake; Christoffersen et al., 2008), we assume that Lake Melville potentially persisted as a subglacial lake underneath the LIS and that its sediments might preserved pre-deglacial paleoclimate history. During expedition MSM84 in 2019, we were able to collect new hydroacoustic data and several sediment cores. Initial sediment-physical measurements and lithological investigations were conducted on three selected sediment cores until now. Two of them (~14 m and 16 m in length) indicate a significant change within the lowermost two metres. Additionally, a preliminary age model of core MSM84_18-1 based on first 14C-dates (bivalve and gastropod remains) provided an extrapolated basal age of ~11.6 ka cal BP, pre-dating the local deglaciation. Furthermore, XRF data was used to make a first correlation attempt between the three cores resulting in extrapolated basal ages of ~9,200 yrs BP (MSM84_9-2) and 12,000 yrs BP (MSM84_26-1) for the two remaining cores. Therefore, we assume that these initial findings, in accordance with sediment echosounder data and microscopic analysis, indicate sediment accumulation in a subglacial lake environment. However, recently conducted pore water analyses of the lowermost section of MSM84_26-1 suggest that the hypothesized subglacial Lake Melville might have been already connected to the Labrador Sea. This new result so far only relies on a few measurements and thus has to be verified by further analyses. However, it already indicates that the original hypothesis of an isolated subglacial lake has to be modified. Therefore, we aim at conducting further multi-proxy analyses as well as significantly improving the age model by considering other dating techniques.

Published
2021
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35. Hydrological variability in southeastern Patagonia and explosive volcanic activity in the southern Andean Cordillera during Oxygen Isotope Stage 3 and the Holocene inferred from lake sediments of Laguna Potrok Aike, Argentina

Author

Haberzettl, Torsten, Kück, Barbara, Wulf, Sabine, Anselmetti, Flavio, Ariztegui, Daniel, Corbella, Hugo, Fey, Michael, Janssen, Stephanie, Lücke, Andreas, Mayr, Christoph, Ohlendorf, Christian, Schäbitz, Frank, Schleser, Gerhard H., Wille, Michael, and Zolitschka, Bernd

Published
2008
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