Erman Özsayin & Kadir DİRİK, KADİR DİRİK

Quaternary Activity of the Cihanbeyli and Yeniceoba Fault Zones: İnönü-Eskişehir Fault System, Central Anatolia

The İnönü-Eskişehir fault system (İEFS) is one of the most important fault systems in Central Anatolia and consists of a series of NW-SE- to WNW-ESE-trending fault zones extending from Uludağ (Bursa) in the northwest to Sultanhanı in the southeast. Between İnönü and Sivrihisar, the Eskişehir fault zone of the İEFS trends WNW, but east of Sivrihisar the İEFS changes its direction to NW-SE and splays out into four fault zones, named the Ilıca, Yeniceoba, Cihanbeyli and Sultanhanı fault zones and extends to south of Tuzgölü in the east. The NW-SE-trending Yeniceoba fault zone (YFZ), exposed between Günyüzü in the west and Yeniceoba in the east, controls the northern margin of the Kelhasan horst and the southern margin of the Yeniceoba basin. Along this fault zone two sets of superimposed slickenlines indicate older pure right-lateral strike-slip faulting and younger normal faulting with a right-lateral component. The NW-SE-trending Cihanbeyli fault zone (CFZ) is well exposed between north of Sülüklü in the west and Cihanbeyli in the east. It controls the southern margin of the Kelhasan horst, and is marked by fault scarps, triangular facets, alluvial fans and alignment of springs. Recent detailed field mapping and kinematic analysis along the fault planes between Pliocene lacustrine carbonates and younger fluvial clastic rocks has shown that the CFZ consists of a series of parallel normal faults. However, kinematic analysis of the fault slip-plane data indicates that the fault planes cutting the Pleistocene-Holocene clastic sediments of the Cihanbeyli Graben at the southeastern tip of the CFZ are normal faults with a minor sinistral component. The kinematic analyses of fault-slip data clearly indicate that the area experienced NNE-SSW extension. Recent horizontal terrace deposits cut by a series of steeply-dipping normal faults with minor strike-slip component in İlhanyayla, Damlakuyu (Çorca) village and nearly 4 kilometres southeast of İnsuyu village, which are located on the YFZ and CFZ, indicate that the activity of both CFZ and YFZ continues, controlled by NNE-SSE-directed extension, in the Quaternary. The distribution of earthquake epicentres supports this view and suggests recent activity along the fault zones.

Anahtar Kelimeler:

Neotectonic, Quaternary activity, kinematic analysis, Tuzgölü, Central Anatolia, İnönü-Eskişehir fault system, Cihanbeyli fault zone, Yeniceoba fault zone

Quaternary Activity of the Cihanbeyli and Yeniceoba Fault Zones: İnönü-Eskişehir Fault System, Central Anatolia

Keywords:

Neotectonic, Quaternary activity, kinematic analysis, Tuzgölü, Central Anatolia, İnönü-Eskişehir fault system, Cihanbeyli fault zone, Yeniceoba fault zone,

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AKSOY, E., İNCEÖZ, M. & KOÇYİ⁄İT, A. 2007. Lake Hazar Basin: a negative flower structure on the East Anatolian Fault System (NAFS), SE Türkiye. Turkish Journal of Earth Sciences 16, 319–338.
ALTUNEL, E. & BARKA, A. 1998. Neotectonic activity of Eskişehir fault zone between İnönü and Sultandere. Geological Bulletin of Turkey 41, 41–52 [in Turkish with English abstract].
BEKER, K. 2002. İnsuyu Kireçtaşları (Karapınar/Konya) Ostrakod Topluluğunun Biyostratigrafik ve Kronostratigrafik İncelenmesi [Biostratigraphic and Chronostratigraphic Investigation of Ostracoda Assemblage of İnsuyu Limestone (Karapınar/Konya)]. MSc Thesis, Hacettepe University [in Turkish with English abstract, unpublished].
BEKTAş, O., EYÜBO⁄LU, Y. & MADEN, M. 2007. Different modes of stress transfer in a strike-slip fault zone: an example from the North Anatolian Fault System in Turkey. Turkish Journal of Earth Sciences 16, 1–12.
BOZKURT, E. 2001. Neotectonics of Turkey – a synthesis. Geodinamica Acta 14, 3–30.
BOZKURT, E. & MITTWEDE, K.S. 2005. Introduction: Evolution of Neogene extensional tectonics of western Turkey. Geodinamica Acta 18, 153–165.
ÇEMEN, İ., GÖNCÜO⁄LU, M.C. & DİRİK. 1999. Structural evolution of the Tuzgölü basin in Central Anatolia, Turkey. Journal of Geology 107, 693–706.
DİRİK, K. 2001. Neotectonic evolution of the northwestward arched segment of the Central Anatolian Fault Zone, central Anatolia, Turkey. Geodinamica Acta 14, 147–158.
DİRİK, K. & EROL, O. 2000. Tuzgölü ve civarının tektonomorfolojik evrimi [Tectonomorphologic evolution of Tuzgölü and surrounding area]. Haymana-Tuzgölü-Ulukışla Basenleri Uygulamalı Çalışması, Aksaray, Abstracts, p. 7–8.
DİRİK, K. & EROL, O. 2003. Tectonomorphologic evolution of Tuzgölü and surrounding area, central Anatolia-Turkey. Turkish Association of Petroleum Geologists, Special Publications 5, 27–46 [in Turkish with English abstract].
DİRİK, K. & GÖNCÜO⁄LU, M.C. 1995. Neogene structural features of the western part of Tuzgölü, Central Turkey. International Earth Sciences Colloquium on the Aegean Region, Abstracts, p. 3.
DİRİK, K. & GÖNCÜO⁄LU, M.C. 1996. Neotectonic characteristics of central Anatolia. International Geology Review 38, 807–817.
ERKÜL, F., HELVACı, C. & SÖZBİLİR, H. 2005. Stratigraphy and geochronology of the Early Miocene volcanic units in the Bigadiç borate basin, Western Turkey. Turkish Journal of Earth Sciences 14, 227–253.
EROL, O. 1969. Tuzgölü Havzasının Jeolojisi ve Jeomorfolojisi [Geology and Geomorphology of Tuzgölü Basin]. TÜBİTAK-MTA Report no. 4220 [in Turkish, unpublished].
ERSOY, Y. & HELVACı, C. 2007. Stratigraphy and geochemical features of the Early Miocene bimodal (ultrapotassic and calc-alkaline) volcanic Activity within the NE-trending Selendi Basin, Western Anatolia, Turkey. Turkish Journal of Earth Sciences 16, 117–139.
GÖNCÜO⁄LU, M.C., DİRİK, K., ERLER, A., YALıNıZ, K., ÖZGÜL, L. & ÇEMEN, İ. 1996. Tuzgölü Havzası Batı Kısmının Temel Jeolojik Sorunları [Basic Geologic Problems of Western Part of Tuzgölü Basin] Turkish Petroleum Corporation (TPAO) Report no. 3753 [in Turkish, unpublished].
KAYMAKCı, N., İNCEÖZ, M. & ERTEPıNAR, P. 2006. 3D-architecture and Neogene evolution of the Malatya basin: inferences for the kinematics of the Malatya and Ovacık fault zones. Turkish Journal of Earth Sciences 15, 123–154.
KOÇYİ⁄İT, A. 1991. Changing stress orientation in progressive intracontinental deformation as indicated by the neotectonics of the Ankara region (NW of Central Anatolia). Association of Turkish Petroleum Geologists Bulletin 3, 48–55.
KOÇYİ⁄İT, A. 2003. General neotectonic characteristics and seismicity of central Anatolia. Turkish Association of Petroleum Geologist Special Publication 5, 1–26 [in Turkish with English abstract].
KOÇYİ⁄İT, A. 2005. The Denizli graben-horst system and the eastern limit of western Anatolian continental extension: basin fill, structure, deformational mode, throw amount and episodic evolutionary history, SW Turkey. Geodinamica Acta 18, 167–208.
KOÇYİ⁄İT, A. & BEYHAN, A. 1998. A new intracontinental transcurrent structure: the Central Anatolian fault zone, Turkey. Tectonophysics 284, 317–336.
KOÇYİ⁄İT, A. & EROL, O. 2001. A tectonic escape structure: Erciyes pull- apart basin, Kayseri, central Anatolia, Turkey. Geodinamica Acta 14, 133–145.
KOÇYİ⁄İT, A., KAYMAKCı, N., ROJAY, B., ÖZCAN, E., DİRİK, K. & ÖZÇELİK, Y. 1991. İnegöl-Bozüyük Arasında Kalan Alanın Jeolojik Etüdü [Geologic Investigation of an Area Between İnegöl-Bozüyük]. Turkish Petroleum Corporation (TPAO) Report no. 3049 [in Turkish, unpublished].
KOÇYİ⁄İT, A. & ÖZACAR, A.A. 2003. Extensional neotectonic regime through the NE edge of the outer Isparta angle, SW Turkey: new field and seismic data. Turkish Journal of Earth Sciences 12, 67–90.
KOÇYİ⁄İT, A., ÜNAY, E., SARAÇ, G. 2000. Episodic graben formation and extensional neotectonic regime in west central Anatolia and the Isparta Angle: a key study in the Akşehir-Afyon graben, Turkey. In: BOZKURT, E., WİNCHESTER, J.A. & PıPER, J.D.A. (eds), Tectonics and Magmatism in Turkey and the Surrounding Area. Geological Society of London, Special Publication, 173, 405–421.
ÖZCAN, A., GÖNCÜO⁄LU, M.C., TURHAN, N., UYSAL, Ş. & ŞENTÜRK, K. 1990. Paleozoic evolution of the Kütahya-Bolkardağı Belt. METU Journal of Pure and Applied Sciences 21, 211220.
ÖZSAYıN, E. & DİRİK, K. 2005. Quaternary activity of Cihanbeyli Fault Zone (Southern segment of Eskişehir-Sultanhanı Fault System). ATAG-9 Active Tectonic Research Group 9thMeeting. 22–24 September 2005, Abstracts Book, 41 [in Turkish].
ŞARO⁄LU, F., EMRE, Ö. & BORAY, A. 1987. Türkiye’nin Diri Fayları ve Depremsellikleri [Seismicity and Active Faults of Turkey]. Mineral Research and Exploration Institute (MTA) of Turkey Report no. 8174 [in Turkish, unpublished].
ŞENGÖR, A.M.C., GÖRÜR, N. & ŞARO⁄LU, F. 1985. Strike-slip faulting and related basin formation in zones of tectonic escape: Turkey as a case study. In: BIDDLEK.T. & CHRISTIE-BLICK, N. (eds), Strike-slip Faulting and Basin Formation. The Society of Economic Paleontologists and Mineralogists, Special Publications, 37, 227–264.
TOKCAER, M., AGOSTINI, S. & SAVAŞÇıN, M.Y. 2005. Geotectonic Setting and origin of the youngest Kula volcanics (Western Anatolia), with a new emplacement model. Turkish Journal of Earth Sciences 14, 143–166.
TUNO⁄LU, C., TEMEL, A. & GENÇO⁄LU, H. 1995. Pliocene ostracoda association and environmental characteristics of Sivrihisar (Eskişehir)-Central Anatolia.In: RIHA, J. (ed), 12th International Ostracoda Symposium, Ostracoda and Biostratigraphy. Belkama, Rotterdam, 265–275.
ULU, Ü., OCAL, H., BULDUK, A.K., KARAKAŞ, M., ARBAS, A., SAÇLı, L, TAŞKıRAN, A., EKMEKÇi, E., ADıR, M., SÖZERi, Ş. & KARABıYıKO⁄LU, M. 1994. Late Cenozoic depositional system of the Cihanbeyli – Karapınar region, southern inner Anatolia: tectonic and climatic implications. 9thGeological Congress of Turkey, Abstracts Book, 149–163 [in Turkish with English abstract].
ÜNALAN, G. & YÜKSEL, V. 1978. Example of an ancient graben: The Haymana-Polatlı basin. Bulletin of the Geological Society of Turkey 21, 165–169.
YALTıRAK, C., YALÇıN, T., BOZKURTO⁄LU, E. & YÜCE, G. 2005. Water-Level changes in shallow wells before and after the 1999 İzmit and Düzce earthquakes and comparison with long-term water-level observations (1999–2004), NW Turkey. Turkish Journal of Earth Sciences 14, 281–309.
YÜCEL-ÖZTÜRK, Y., HELVACı, C. & SATıR, M. 2005. Genetic relations between skarn mineralization and petrogenesis of the Evciler Granitoid, Kazdağ, Çanakkale, Turkey and comparison with world skarn granitoids. Turkish Journal of Earth Sciences 14, 255–280.