Aral Okay Research

Prof. Aral I. Okay

Currently my research centers on two partly overlapping fields:

Regional Geology and

Metamorphic petrology

Regional Geology

I work to understand the Phanerozoic tectonic evolution of the Eastern Mediterranean and Black Sea region, and specifically Turkey. It is a fascinating orogenic area shaped by subductions and continental collisions over the last 400 million years. There are also several episodes of rifting, ocean floor spreading and strike-slip faulting.

I spend several months each summer in the field, mapping and collecting structural, petrographic, sedimentological and paleontological data in various regions of Turkey. The field data is combined with petrological, geochronological and geochemical data to decipher the tectonic evolution of the region. The few selected recent papers below illustrate the type of research we are doing:

Okay, A.I., Satır, M., Zattin, M., Cavazza, W. & Topuz, G., 2008, An Oligocene ductile strike-slip shear zone: Uludağ Massif, northwest Turkey – implications for the escape tectonics. Geological Society of America Bulletin, 120, 893–911

Okay, A.I., Tüysüz, O., Satır, M., Özkan-Altıner, S., Altıner, D., Sherlock, S., & Eren, R.H., 2006, Cretaceous and Triassic subduction-accretion, HP/LT metamorphism and continental growth in the Central Pontides, Turkey. Geological Society of America Bulletin, 118, 1247-1269.

Okay, A.I., Tüysüz, O. & Kaya, Ş., 2004, From transpression to transtension: Changes in morphology and structure around a bend on the North Anatolian Fault in the Marmara region. Tectonophysics, 391, 259-282

Okay, A.I. & Göncüoğlu,M.C., 2004, Karakaya Complex: a review of data and concepts. Turkish Journal of Earth Sciences, 13, 77-95.

Metamorphic Petrology

Over many years I have been fascinated by the geology of the high and ultrahigh pressure metamorphic rocks. Their mineralogy is interesting with unusual minerals, such as jadeite, glaucophane, lawsonite, coesite, aragonite… They also indicate deep burial and subsequent exhumation of oceanic and continental crust, and provide valuable constraints on the thermal structure of the downgoing lithosphere, as well as on the temporal evolution of subduction zones. The few selected recent papers below illustrate my research in HP rocks:

Topuz, G., Okay, A.I., Altherr, R., Satir, M., Schwarz, W.H., 2008, Late Cretaceous blueschist-facies metamorphism in southeastern Thrace (Turkey) and its geodynamic implications. Journal of Metamorphic Geology, 26, 895–913.

Topuz, G., Okay, A.I., Altherr, R., Meyer, H.P. & Nasdala, L., 2006, Partial high-pressure aragonitization of micritic limestones in an accretionary complex, Tavşanlı Zone, NW Turkey. Journal of Metamorphic Geology, 24, 603-613.

Okay, A.I., 2002, Jadeite-chloritoid-glaucophane-lawsonite schists from northwest Turkey: unusually high P/T ratios in continental crust. Journal of Metamorphic Geology, 20, 757-768.

Okay, A.I., Monod, O. & Monié, P., 2002, Triassic blueschists and eclogites from northwest Turkey: vestiges of the Paleo-Tethyan subduction. Lithos, 64, 155-178.

Research Students

Ph.D.

Serdar Akyüz, 1995

Sarah Sherlock, 1999

Cenk Yaltırak, 2003

Zaide Özgörüş

Kenan Akbayram

M.Sc.