Βιοστρωματογραφία, Ιζηματολογία, Σταθερά Ισότοπα και Οργανικό Υλικό των Ιουρασικών Ιζημάτων της Δυτικής Ελλάδας

Doctoral Dissertation uoadl:1308774 600 Read counter

Unit:
Τομέας Ιστορικής Γεωλογίας και Παλαιοντολογίας
Library of the School of Science
Deposit date:
2012-03-29
Year:
2012
Author:
Καφούσια Νεφέλη
Dissertation committee:
Καθηγητής Βασίλειος Καρακίτσιος
Original Title:
Βιοστρωματογραφία, Ιζηματολογία, Σταθερά Ισότοπα και Οργανικό Υλικό των Ιουρασικών Ιζημάτων της Δυτικής Ελλάδας
Languages:
Greek
Summary:
This thesis concerns the study of the Lower Jurassic and particularly the
Toarcian, where an oceanic anoxic event has been recorded at about 183 Ma ago.
The Toarcian Oceanic Anoxic Event (T-OAE) has been studied here in five
different sections from western Greece. The aim of this study is to recognize
the Toarcian sediments of these the Ionian and the Pindos Zone and to
investigate if the T-OAE has been recorded in each one of these. Moreover where
it has been recorded, further research has been conducted in order to extract
more information about the palaeoenvironment. The T-OAE coincides with marine
anoxia to euxinia, high palaeotemperatures, high CO2, sea transgression and
mass extinctions. In order to recognize this event it is essential to find a
positive excursion in total organic carbon (TOC) and a negative and/or positive
excursion in carbon isotopes. The geochemical characteristics that have been
studied here, are the TOC, δ13Ccarb, δ13Corg, δ18Ocarb, δ34SCAS, δ18OCAS and
pyrite framboids. Analyzing the first three, leaves no doubt that the T-OAE has
been recorded in both Zones. Thus, a detailed look at all the biogeochemical
characteristics makes clear that the T-OAE has not been recorded in the same
way in any of the sections. In conclusion, this thesis confirms that the
Toarcian Oceanic Anoxic Event is a global event with the regional character.
Keywords:
Toarcian, Oceanic Anoxic Event, Ionian Zone, Pindos Zone, ocean basin
Index:
Yes
Number of index pages:
ix-xxi
Contains images:
Yes
Number of references:
270
Number of pages:
xxvi, 257
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