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Dr Alexandra Nederbragt
Arbenigwr Sbectromedr Màs Isotop Sefydlog
Ysgol Gwyddorau'r Ddaear a'r Amgylchedd
- NederbragtA@caerdydd.ac.uk
- Y Prif Adeilad, Ystafell 1.56, Plas y Parc, Caerdydd, CF10 3AT
Trosolwyg
Rwy'n rhedeg y cyfleuster isotop sefydlog, lle rydym yn mesur isotopau ysgafn (H, C, N, O) mewn ystod o ddeunyddiau. Mae'r cyfleuster yn darparu gwasanaeth i Ysgol Gwyddorau'r Ddaear a'r Amgylchedd yn ogystal ag ysgolion eraill ym Mhrifysgol Caerdydd ac ymchwilwyr o sefydliadau eraill.
Cyhoeddiad
2023
- Nederbragt, A. J. 2023. The effect of seawater carbonate chemistry on the stable isotope composition of Cibicidoides wuellerstorfi and other Cibicidoides species. Paleoceanography and Paleoclimatology 38(9), article number: e2023PA004667. (10.1029/2023PA004667)
2022
- Barker, S. et al. 2022. Persistent influence of precession on northern ice sheet variability since the early Pleistocene. Science 376(6596), pp. 961-967. (10.1126/science.abm4033)
2021
- Scorrer, J. et al. 2021. Diversity aboard a Tudor warship: investigating the origins of the Mary Rose crew using multi-isotope analysis. Royal Society Open Science 8(5), article number: 202106. (10.1098/rsos.202106)
- Madgwick, R., Lamb, A., Sloane, H., Nederbragt, A., Albarella, U., Parker Pearson, M. and Evans, J. 2021. A veritable confusion: use and abuse of isotope analysis in archaeology. Archaeological Journal 178(2), pp. 361-385. (10.1080/00665983.2021.1911099)
2020
- Craig-Atkins, E. et al. 2020. The dietary impact of the Norman Conquest: a multiproxy archaeological investigation of Oxford, UK. PLoS ONE 15(7), article number: e0235005. (10.1371/journal.pone.0235005)
2019
- Madgwick, R., Grimes, V., Lamb, A. L., Nederbragt, A. J., Evans, J. A. and McCormick, F. 2019. Feasting and mobility in Iron Age Ireland: Multi-isotope analysis reveals the vast catchment of Navan Fort, Ulster. Scientific Reports 9(1), article number: 19792. (10.1038/s41598-019-55671-0)
- Madgwick, R., Lamb, A. L., Sloane, H., Nederbragt, A. J., Albarella, U., Parker Pearson, M. and Evans, J. A. 2019. Multi-isotope analysis reveals that feasts in the Stonehenge environs and across Wessex drew people and animals from throughout Britain. Science Advances 5(3), article number: eaau6078. (10.1126/sciadv.aau6078)
2018
- Dodd, M. S., Papineau, D., She, Z., Fogel, M. L., Nederbragt, S. and Pirajno, F. 2018. Organic remains in late Palaeoproterozoic granular iron formations and implications for the origin of granules. Precambrian Research 310, pp. 133-152. (10.1016/j.precamres.2018.02.016)
- Dias, R. et al. 2018. Mesolithic human occupation and seasonality: sclerochronology, δ18O isotope geochemistry, and diagenesis verification by Raman and LA-ICP-MS analysis of Argyrosomus regius (meagre) sagittae otoliths from layer 1 of Cabeço da Amoreira Mesolithic shell midden (Muge, Portugal). Archaeological and Anthropological Sciences (10.1007/s12520-017-0569-3)
2016
- Reynolds, D. J. et al. 2016. Annually resolved North Atlantic marine climate over the last millennium. Nature Communications 7, article number: 13502. (10.1038/ncomms13502)
2011
- Littler, K., Robinson, S. A., Bown, P. R., Nederbragt, A. J. and Pancost, R. D. 2011. High sea-surface temperatures during the Early Cretaceous Epoch [Letter]. Nature Geoscience 4(3), pp. 169-172. (10.1038/ngeo1081)
2010
- Tyler, J. J., Nederbragt, A. J., Jones, V. J. and Thurow, J. W. 2010. Assessing past temperature and soil pH estimates from bacterial tetraether membrane lipids: Evidence from the recent lake sediments of Lochnagar, Scotland. Journal of Geophysical Research: Biogeosciences 115, article number: G01015. (10.1029/2009JG001109)
2009
- Schouten, S. et al. 2009. An interlaboratory study of TEX86 and BIT analysis using high-performance liquid chromatography-mass spectrometry. Geochemistry Geophysics Geosystems 10(3), article number: Q03012. (10.1029/2008GC002221)
2008
- Robinson, S. A., Clarke, L. J., Nederbragt, A. J. and Wood, I. G. 2008. Mid-Cretaceous oceanic anoxic events in the Pacific Ocean revealed by carbon-isotope stratigraphy of the Calera Limestone, California, USA. Geological Society of America Bulletin 120(11-12), pp. 1416-1426. (10.1130/B26350.1)
- Nederbragt, A. J., Thurow, J. W. and Bown, P. R. 2008. Paleoproductivity, ventilation, and organic carbon burial in the Santa Barbara Basin (ODP Site 893, off California) since the last glacial. Paleoceanography 23(1), article number: PA1211. (10.1029/2007PA001501)
2005
- Cheshire, H., Thurow, J. W. and Nederbragt, A. J. 2005. Late Quaternary climate change record from two long sediment cores from Guaymas Basin, Gulf of California. Journal of Quaternary Science 20(5), pp. 457-469. (10.1002/jqs.944)
- Nederbragt, A. J. and Thurow, J. 2005. Amplitude of ENSO cycles in the Santa Barbara Basin, off California, during the past 15 000 years. Journal of Quaternary Science 20(5), pp. 447-456. (10.1002/jqs.946)
- Nederbragt, A. J. and Thurow, J. 2005. Geographic coherence of millennial-scale climate cycles during the Holocene. Palaeogeography, Palaeoclimatology, Palaeoecology 221(3-4), pp. 313-324. (10.1016/j.palaeo.2005.03.002)
- Kuhnt, W., Luderer, F., Nederbragt, A. J., Thurow, J. and Wagner, T. 2005. Orbital-scale record of the late Cenomanian-Turonian oceanic anoxic event (OAE-2) in the Tarfaya Basin (Morocco). International Journal of Earth Sciences 94(1), pp. 147-159. (10.1007/s00531-004-0440-5)
2004
- Nederbragt, A. J., Thurow, J. W., Vonhof, H. and Brumsack, H. 2004. Modelling oceanic carbon and phosphorus fluxes: implications for the cause of the late Cenomanian Oceanic Anoxic Event (OAE2). Journal of the Geological Society 161(4), pp. 721-728. (10.1144/0016-764903-075)
2001
- Nederbragt, A. J. and Thurow, J. W. 2001. A 6000 yr varve record of Holocene climate in Saanich Inlet, British Columbia, from digital sediment colour analysis of ODP Leg 169S cores. Marine Geology 174(1-4), pp. 95-110. (10.1016/S0025-3227(00)00144-4)
- Nederbragt, A. J., Fiorentino, A. and Klosowska, B. 2001. Quantitative analysis of calcareous microfossils across the Albian-Cenomanian boundary oceanic anoxic event at DSDP Site 547 (North Atlantic). Palaeogeography, Palaeoclimatology, Palaeoecology 166(3-4), pp. 401-421. (10.1016/S0031-0182(00)00227-3)
2000
- Vonhof, H. B., Smit, J., Brinkhuis, H., Montanari, A. and Nederbragt, A. J. 2000. Global cooling accelerated by early late Eocene impacts?. Geology 28(8), pp. 687-690. (10.1130/0091-7613(2000)28<687:GCABEL>2.0.CO;2)
- Erlich, R. N., Macsotay, O., Nederbragt, A. J. and Lorente, M. A. 2000. Birth and death of the Late Cretaceous "La Luna Sea", and origin of the Tres Esquinas phosphorites. Journal of South American Earth Sciences 13(1-2), pp. 21-45. (10.1016/S0895-9811(00)00016-X)
Articles
- Nederbragt, A. J. 2023. The effect of seawater carbonate chemistry on the stable isotope composition of Cibicidoides wuellerstorfi and other Cibicidoides species. Paleoceanography and Paleoclimatology 38(9), article number: e2023PA004667. (10.1029/2023PA004667)
- Barker, S. et al. 2022. Persistent influence of precession on northern ice sheet variability since the early Pleistocene. Science 376(6596), pp. 961-967. (10.1126/science.abm4033)
- Scorrer, J. et al. 2021. Diversity aboard a Tudor warship: investigating the origins of the Mary Rose crew using multi-isotope analysis. Royal Society Open Science 8(5), article number: 202106. (10.1098/rsos.202106)
- Madgwick, R., Lamb, A., Sloane, H., Nederbragt, A., Albarella, U., Parker Pearson, M. and Evans, J. 2021. A veritable confusion: use and abuse of isotope analysis in archaeology. Archaeological Journal 178(2), pp. 361-385. (10.1080/00665983.2021.1911099)
- Craig-Atkins, E. et al. 2020. The dietary impact of the Norman Conquest: a multiproxy archaeological investigation of Oxford, UK. PLoS ONE 15(7), article number: e0235005. (10.1371/journal.pone.0235005)
- Madgwick, R., Grimes, V., Lamb, A. L., Nederbragt, A. J., Evans, J. A. and McCormick, F. 2019. Feasting and mobility in Iron Age Ireland: Multi-isotope analysis reveals the vast catchment of Navan Fort, Ulster. Scientific Reports 9(1), article number: 19792. (10.1038/s41598-019-55671-0)
- Madgwick, R., Lamb, A. L., Sloane, H., Nederbragt, A. J., Albarella, U., Parker Pearson, M. and Evans, J. A. 2019. Multi-isotope analysis reveals that feasts in the Stonehenge environs and across Wessex drew people and animals from throughout Britain. Science Advances 5(3), article number: eaau6078. (10.1126/sciadv.aau6078)
- Dodd, M. S., Papineau, D., She, Z., Fogel, M. L., Nederbragt, S. and Pirajno, F. 2018. Organic remains in late Palaeoproterozoic granular iron formations and implications for the origin of granules. Precambrian Research 310, pp. 133-152. (10.1016/j.precamres.2018.02.016)
- Dias, R. et al. 2018. Mesolithic human occupation and seasonality: sclerochronology, δ18O isotope geochemistry, and diagenesis verification by Raman and LA-ICP-MS analysis of Argyrosomus regius (meagre) sagittae otoliths from layer 1 of Cabeço da Amoreira Mesolithic shell midden (Muge, Portugal). Archaeological and Anthropological Sciences (10.1007/s12520-017-0569-3)
- Reynolds, D. J. et al. 2016. Annually resolved North Atlantic marine climate over the last millennium. Nature Communications 7, article number: 13502. (10.1038/ncomms13502)
- Littler, K., Robinson, S. A., Bown, P. R., Nederbragt, A. J. and Pancost, R. D. 2011. High sea-surface temperatures during the Early Cretaceous Epoch [Letter]. Nature Geoscience 4(3), pp. 169-172. (10.1038/ngeo1081)
- Tyler, J. J., Nederbragt, A. J., Jones, V. J. and Thurow, J. W. 2010. Assessing past temperature and soil pH estimates from bacterial tetraether membrane lipids: Evidence from the recent lake sediments of Lochnagar, Scotland. Journal of Geophysical Research: Biogeosciences 115, article number: G01015. (10.1029/2009JG001109)
- Schouten, S. et al. 2009. An interlaboratory study of TEX86 and BIT analysis using high-performance liquid chromatography-mass spectrometry. Geochemistry Geophysics Geosystems 10(3), article number: Q03012. (10.1029/2008GC002221)
- Robinson, S. A., Clarke, L. J., Nederbragt, A. J. and Wood, I. G. 2008. Mid-Cretaceous oceanic anoxic events in the Pacific Ocean revealed by carbon-isotope stratigraphy of the Calera Limestone, California, USA. Geological Society of America Bulletin 120(11-12), pp. 1416-1426. (10.1130/B26350.1)
- Nederbragt, A. J., Thurow, J. W. and Bown, P. R. 2008. Paleoproductivity, ventilation, and organic carbon burial in the Santa Barbara Basin (ODP Site 893, off California) since the last glacial. Paleoceanography 23(1), article number: PA1211. (10.1029/2007PA001501)
- Cheshire, H., Thurow, J. W. and Nederbragt, A. J. 2005. Late Quaternary climate change record from two long sediment cores from Guaymas Basin, Gulf of California. Journal of Quaternary Science 20(5), pp. 457-469. (10.1002/jqs.944)
- Nederbragt, A. J. and Thurow, J. 2005. Amplitude of ENSO cycles in the Santa Barbara Basin, off California, during the past 15 000 years. Journal of Quaternary Science 20(5), pp. 447-456. (10.1002/jqs.946)
- Nederbragt, A. J. and Thurow, J. 2005. Geographic coherence of millennial-scale climate cycles during the Holocene. Palaeogeography, Palaeoclimatology, Palaeoecology 221(3-4), pp. 313-324. (10.1016/j.palaeo.2005.03.002)
- Kuhnt, W., Luderer, F., Nederbragt, A. J., Thurow, J. and Wagner, T. 2005. Orbital-scale record of the late Cenomanian-Turonian oceanic anoxic event (OAE-2) in the Tarfaya Basin (Morocco). International Journal of Earth Sciences 94(1), pp. 147-159. (10.1007/s00531-004-0440-5)
- Nederbragt, A. J., Thurow, J. W., Vonhof, H. and Brumsack, H. 2004. Modelling oceanic carbon and phosphorus fluxes: implications for the cause of the late Cenomanian Oceanic Anoxic Event (OAE2). Journal of the Geological Society 161(4), pp. 721-728. (10.1144/0016-764903-075)
- Nederbragt, A. J. and Thurow, J. W. 2001. A 6000 yr varve record of Holocene climate in Saanich Inlet, British Columbia, from digital sediment colour analysis of ODP Leg 169S cores. Marine Geology 174(1-4), pp. 95-110. (10.1016/S0025-3227(00)00144-4)
- Nederbragt, A. J., Fiorentino, A. and Klosowska, B. 2001. Quantitative analysis of calcareous microfossils across the Albian-Cenomanian boundary oceanic anoxic event at DSDP Site 547 (North Atlantic). Palaeogeography, Palaeoclimatology, Palaeoecology 166(3-4), pp. 401-421. (10.1016/S0031-0182(00)00227-3)
- Vonhof, H. B., Smit, J., Brinkhuis, H., Montanari, A. and Nederbragt, A. J. 2000. Global cooling accelerated by early late Eocene impacts?. Geology 28(8), pp. 687-690. (10.1130/0091-7613(2000)28<687:GCABEL>2.0.CO;2)
- Erlich, R. N., Macsotay, O., Nederbragt, A. J. and Lorente, M. A. 2000. Birth and death of the Late Cretaceous "La Luna Sea", and origin of the Tres Esquinas phosphorites. Journal of South American Earth Sciences 13(1-2), pp. 21-45. (10.1016/S0895-9811(00)00016-X)
Ymchwil
Much of my research to date stems from my interest in the Cretaceous period as an example of a greenhouse world with climate conditions that are fundamentally different from the modern icehouse setting. Especially the mid-Cretaceous (120-90 Ma years ago) was a time of optimum warmth during which the global ocean was periodically anoxic. During these so-call Oceanic Anoxic Events organic-rich sediments were deposited at a scale that is inconceivable in the modern ocean. I have used micropalaeontology, stable isotope stratigraphy, and 2-box ocean modelling to try to understand the mechanisms that are responsible for these climate events and their impact on the global carbon cycle.
To better quantify the relation between organic matter production, sedimentation, and preservation I have looked at anoxic basins in the modern ocean. Due to lack of bioturbation at the sea floor the seasonal variation in sediment composition is preserved as varved sediments. By measuring the composition of such varves it is possible to reconstruct the accumulation rates of organic matter at annual resolution and relate it to other indicators for climate change, something that is rarely possible for ancient sediments. The main result was that sedimentation of organic matter is largely controlled by the presence of other sediment particles (ballast minerals). Calcareous microsfossils are the main ballast particles in the open ocean. However, riverine sediments are much more important as ballast mineral in near-coastal basins, implying that organic carbon burial in the oceans is sensitive to changes in river discharge either natural or man-made.
My interest for future research is to revisit the geologic past to explore what role ballast minerals played in ancient settings. During much of the past, like the mid-Cretaceous, lithogenic sedimentation rates were low, and calcareous microfossils must have been the main ballast mineral that was available. However, severe carbonate dissolution is common in anoxic sediments. This suggests that the production and preservation of both organic matter and carbonate are intrinsically linked.
Bywgraffiad
- M.Sc. Earth Sciences, VU University Amsterdam, the Netherlands (1985)
- Ph.D. Micropalaeontology, VU University Amsterdam (1990)
- Post-doctoral Researcher, VU University Amsterdam (1990-1997)
- Post-doctoral Researcher, University College London, UK (1997-2008)
- Stable Isotope Mass Spectrometer Specialist, Cardiff University, since 2012
Safleoedd academaidd blaenorol
- Ymchwilydd Ôl-ddoethurol – Adran Gwyddorau Daear, Coleg Prifysgol Llundain (1997-2008)
- Ymchwilydd Ôl-ddoethurol - Sefydliad Gwyddorau Daear, Prifysgol VU Amsterdam (1991-1997)