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| Titel |
Understanding the Tectonic Deformation of Turkish Blocks since Mesozoic; A Paleomagnetic study on the Nigde-Kirsehir Massif and the Taurides |
| VerfasserIn |
Cinku Mualla, Mumtaz Hisarli, Beyza Ülker, Nurcan Kaya, Erdinc Oksum, Yücel Yilmaz, Naci Orbay |
| 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 |
250101078
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| Publikation (Nr.) |
 EGU/EGU2015-175.pdf |
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| Zusammenfassung |
| It is reported that the Nigde-Kirsehir massif which constitutes the main fragment of Anatolia
is rifted from the Taurides-Anatolides in Mesozoic and that the Intra-Tauride ocean exist
between these blocks. Another group of researchers believed that the Intra Tauride ocean did
not exist. They assumed that the Nigde-Kirsehir massif existed as a promotory of the
Taurides. In this sense, both the Nigde-Kirsehir massif and the Taurides experienced
several deformation phases due to the consumption of the oceanic strand (s) and the
amalgamation of the Anatolian blocks after collision in the end of the paleotectonic time,
whereas in the neotectonic time the traces of the westwards excursion of Anatolia was
effective.
Previous paleomagnetic studies showed that the Nigde-Kirsehir massif rotated 90Ë
anticlockwise during Jurassic to Eocene time and other studies showed that the collision
between the Nigde-Kirsehir massif and the Pontides resulted by deformation which was
accomodated by regional faults. In the south of the Nigde-Kirsehir massif, it was proposed
that all the rocks in Carboniferous to Eosen were remagnetized due to nap emplacement in
Eocene.
Because of several alternative interpretations about the tectonic deformation of the
Nigde-Kirsehir massif in relation between the Taurides and the Pontides, we report new
paleomagnetic results from Late Jurassic to Miocene rocks in the Nigde-Kirsehir
massif and its surrounding. A total of 138 different sites were sampled from Jurassic
to Miocene rocks in the south of the Nigde-Kirsehir massif around Ki ri kkale,
Tuzgölü, Uluki şla and Kayseri, whereas in the Central Taurides Late Jurassic- Lower
Cretaceous platform type carbonates and ophiolitic rocks from Mersin and Pozanti were
collected.
Paleomagnetic results evaluated together with previous paleomagnetic data indicate that
all the studied rocks carry a magnetization before folding according to positive
incremental fold tests. It has been shown that in the SE/E (SE Taurides) and the
SW/W (Central Taurides) area two different sense of rotation occured. In the SE/E
area, counterclockwise rotation of 18°took place in the period between Lower
Cretaceous–Middle Eocene. The rotations are consistent with the thrust directions, indicating
evidence for the consumption of the Intra Tauride ocean in Late Cretaceous. This result was
supported by the paleolatitudes obtained for the Taurides and the Niğde Ki rşehir massif
which showed a spatial gap of 1000 km between the Pontides and the Taurides
in Late Jurassic- Lower Cretaceous and Late Cretaceous. In the SW/W, however,
clockwise rotation of 47°between Middle Eocene and Miocene time, imply that the
deformation occured in a later phase as a result of consumption of the South Neotethys
ocean and the collision between the African and Eurasian plates. Accordingly to the
paleomagnetic rotations which took place gradually in the SE/E area in Middle
Eocene, it is shown that counterclockwise rotations of 25°took place in the Niğde
Ki rşehir massif during Paleocene. This implies that the Nigde-Kirsehir massif
underwent similar deformation together with the adjacent block in the SE/E. In the
Neotectonic period, counterclockwise rotation of 17°was obtained in the SE/E area.
It is shown that the westwards movement of Anatolia affected mainly the SE/E
ares despite the SW/W and the Nigde-Kirsehir massif, which show no significant
rotations.
This study was financially supported by the project of the Scientific and Technical
Research Council of Turkey (TUBITAK) with Project number 111Y043. |
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