| The opening
or closing of oceanic gateways – often of tectonic origin - play an important
role in Earth’s geodynamic, palaeogeographic and climatic evolution. The
closure of the Mediterranean-Indian Ocean gateway marks a major factor
in the Neogene history of the (circum)Mediterranean area.
Research evidences
that the middle Miocene has been a time of drastic climatic changes towards
a colder climate (~ 13 Ma), but the timing of closure of the Mediterranean
- Indian gateway is unknown. It may have followed the climate change (e.g.
by sea- |
level lowering),
or it may have preceeded this change (e.g. tectonic closure in the Africa
- Europe convergence zone), and caused the climatic change.
In general, processes
governing (or following) climatic changes are still obscure, and in particular
for this important Middle Miocene global cooling event. Studies on the
Mediterranean-Indian gateway closure are not only virtually non-existent,
but, in particular, they lack the accurate age control necessary to distinguish
cause-and- consequence of geodynamic vs. climatic changes. |
Miocene
biogeography of the circum-Mediterranean area (after Harzhauser et al.,
2002)
We propose an approach
on sedimentary sequences sections that enables to trace the closure, accurately
date it and elucidate the related effects. The research follows a spatial
and temporal approach.
Hoya
village and section (Eocene - Miocene limestones) in SE Anatolia
| Firstly,
we aim at establishing a high- resolution time scale in Early and Middle
Miocene sections from the eastern Mediterranean, the area of the once-existing
ocean gateway, namely southeastern Turkey. An integrated stratigraphy approach
will be used. |
Secondly,
these sections, and therefore the history of the gateway, will be spatially
compared with astronomically dated and – in part – already analysed sections
in the Central Mediterranean (northern Italy, Tremiti Islands, Malta). |
Silja
drilling in the river section near Antakya, SE Turkey
Detailed rock magnetic
and geochemical analyses will subsequently be carried out for an environmental
investigation on these available sections and on suitable new sections.
We use the advantage of already existing records of middle Miocene sections
(Monte dei Corvi, Tremiti, Malta) - the few in the world spanning the (astronomically
dated) time interval from approximately 11 to 16 Ma. |
2008
-
Huesin, S. (2008). Astrochronology
of the Mediterranean Miocene: Linking palaeoenvironmental changes to gateway
dynamics (PhD Thesis Utrecht University), Geologica Ultraiectina, 295,
171 pp.
-
Hüsing, S.K., Zachariasse,
W.J., Van Hinsbergen, D.J.J., Krijgsman, W., Inceöz, M., Harzhauser,
M., Mandic, O. and Kroh, A. (2008). Oligo-Miocene foreland basin
evolution in SE Anatolia: implications for the closure of the eastern Tethys
gateway, In: Van Hinsbergen, D.J.J., Edwards, M.A. and Govers, R. (editors),
Geodynamics of Collision and Collapse at the Africa-Arabia-Eurasia subduction
zone, Geological Society of London Special Publication, in press
-
Dupont-Nivet, G., Sier,
M., Campisano, C.J., Arrowsmith, J.R., DiMaggio, E.N., Reed, K., Lockwood,
C.A., Franke, C., and Huesing, S. (2009), Magnetostratigraphy of the eastern
Hadar Basin (Ledi-Geraru research area, Ethiopia), implications for hominin
paleoenvironments, In: Quade, J., and Wynn, J.G. (eds.),
The Geology of Early Humans in the Horn of Africa, The Geological society
of America Special Paper xxx, in press.
2007
-
Hüsing, S.K., Hilgen,
F.J., Abdul Aziz, H. and Krijgsman, W. (2007). Completing the Neogene geological
time scale between 8.5 and 12.5 Ma, Earth Planet. Sci. Lett., 253,
340-358
|
