CALL FOR PROPOSALS:

ORGANIZERS

  • Harvey Thorleifson, Chair
    Minnesota Geological Survey
  • Carrie Jennings, Vice Chair
    Minnesota Geological Survey
  • David Bush, Technical Program Chair
    University of West Georgia
  • Jim Miller, Field Trip Chair
    University of Minnesota Duluth
  • Curtis M. Hudak, Sponsorship Chair
    Foth Infrastructure & Environment, LLC

 

Paper No. 7
Presentation Time: 10:00 AM

REGIONAL GEOLOGY AND TECTONICS OF THE SOUTH EAST ANATOLIAN FOLD AND TRUST BELT AND ITS FORELAND EVOLUTION


YILMAZ, Yucel, Faculty of Science, Kadir Has University, Cibali Merkez Kampusu Cibali, Istanbul, 34230-01, Turkey, yyilmaz@khas.edu.tr

Two contrasting morphologic features dominate southeast Anatolia: east-west-trending mountain ranges in the north and a flat, low-lying plain in the south. Geologically these correspond with the southeast Anatolian Alpide orogenic segment and the Arabian Platform, respectively.

Southeastern Anatolia underwent two major episodes of Alpide deformation. The first occurred during the Late Cretaceous period, when ophiolite was emplaced on the Arabian Platform. This event was not the consequence of a continental collision. The ophiolite obduction onto the Arabian Platform was followed by a regionwide extension and a new marine transgression over the platform immediately after the ophiolite obduction. The second episode of deformation occurred during the Miocene time as a result of the progressive elimination and complete closure of the ocean(s) which led to the collision between the zone of nappes.

SE Anatolian orogenic belt may be divided into three east-west-trending zones. From south to north, they are the Arabian Platform, followed by a zone of imbrication, and then a zone of nappes. The Arabian Platform includes a mostly marine, sedimentary succession deposited from early Cambrian to middle Miocene time. The zone of imbrication is a narrow belt sandwiched between the Arabian Platform and the zone of nappes. It consists of imbricated thrust slices emplaced onto the Arabian Platform during the Miocene.

During the ophiolite emplacement period in the late Cretaceous, rocks belonging to abyssal-plain/continental-apron and lower continental-shelf environments were shortened and pushed on top of each other in front of the ophiolite and were incorporated into the advancing allochthon.

As the rate of subsidence of the platform increased along with the approach of the allochthons, the foredeep migrated onto it. Deposition of pelagic units was followed. During the final emplacement of the ophiolitic allochthon, the platform was also locally imbricated and severely deformed. The foreland has passed through thin and thick-skinned deformations as the nappes moved over the passive margin sequence.

The structures generated by the nappe emplacement episodes in southeast Anatolia have many features in common with other foreland fold and thrust belts. In this paper such features will be discussed in comparative sense.

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