Structural Analysis of Misis Frontal Thrust System, Iskenderun Basin, Turkey

Alan P. Morris1, David A. Ferrill2, Craig Davis3, Gary Fortier3, Haki Naz4, Tevfik Efecinar4, Emrah Can4, and Ismail Yilmaz4. (1) Department of Earth and Environmental Science, University of Texas San Antonio, San Antonio, TX 78249, phone: 210 458 5450, alanm52@flash.net, (2) CNWRA, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238, (3) El Paso Production Company, Nine Greenway Plaza #1728, Houston, TX 77046, (4) TPAO, Ankara, Turkey

Northward movement of Africa relative to Europe and Asia since 50 Ma has resulted in the oblique subduction of Mediterranean (Tethyan) oceanic crust beneath Turkey, and the formation of a fold-thrust belt in the off-scraped sedimentary strata along the eastern edge of the Misis uplift. At the same time the Mediterranean basin became increasingly restricted and from about 6.8 Ma to about 5.3 Ma numerous isolated, peripheral basins became sites for evaporite deposition, culminating in the total desiccation of the Mediterranean - the Messinian salinity crisis. The sudden return to deep water marine conditions occurred shortly after 5.3 Ma. Detailed structural analysis of seismic reflection and well data from the eastern flank of the Misis uplift documents a frontal thrust system with approximately 17 km of strike-normal contraction during the 1.5 million years between 6.8 and 5.3 Ma. In the earlier part of this evolution, structural growth outpaced sea level drop and early-formed structures were decapitated by erosion. However, piggy-back basins in synclinal depressions continued to receive sediment and exhibit syn-deformational sedimentary growth sequences. Later, rapid regression of the shrinking Mediterranean deposited evaporites across the southeast-dipping paleoslope of the fold-thrust belt. These evaporites then became incorporated into the thrust package during the latest phases of thrusting. Subsequent return to deep water conditions buried the fold-thrust belt under a largely undeformed cover of deep water shales.