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| Titel |
Evidence of volcanic induced environmental stress during the end-Triassic event |
| VerfasserIn |
Sofie Lindström, Hamed Sanei, Bas van de Schootbrugge, Gunver Krarup Pedersen, Karen Dybkjær, Carolien van der Weijst, Katrine Hovedskov Hansen |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250109424
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| Publikation (Nr.) |
 EGU/EGU2015-9330.pdf |
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| Zusammenfassung |
| The end-Triassic biotic crisis is generally explained by massive input of CO2 and/or methane
to the atmosphere linked to the formation of the Central Atlantic Magmatic Province. Such
massive volcanism can be compared to industrial pollution releasing large amounts of the
greenhouse gases CO2 and SO2 to the atmosphere. Indeed, the fossil record provides
evidence of major perturbations in the δ13C-record of both calcareous and organic
material. In the marine realm loss of calcifying organisms provides evidence of ocean
acidification due to the increased pCO2, while in the terrestrial realm physiological
responses in fossil plants indicate intense global warming across the Triassic-Jurassic
boundary. Changing climatic conditions is further indicated by charcoal records
from Greenland, Denmark, Sweden and Poland showing increased wildfire activity.
Increased reworking of palynological material and marked changes in fluvial style in
terrestrial successions seem to indicate an increased hydrological cycle. Here we
examine and compare two proxies, Mercury and palynology, that may both, each in
their own way, indicate volcanic induced environmental stress. Mercury (Hg) is
one of the most toxic elements on the planet, with volcanic emissions being the
largest natural input to the Hg-cycle. The temporal distribution of Hg in relation
to organic matter can provide evidence of atmospheric Hg loading on the marine
ecosystem. In the terrestrial realm, pollen and spores are known to be sensitive
bioindicators of atmospheric pollution and environmental stress. Quantitive abundances of
aberrant, and thus probably non-viable, pollen and spores are often used to assess
environmental impact on polluted sites today. We present, compare and discuss
Hg and aberrant spore/pollen records from the stratigraphically well-constrained
Triassic-Jurassic boundary succession at Stenlille in the Danish Basin, and the possible
impact of these data on the interpretation of events during end-Triassic biotic crisis. |
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