The 2005 - 2007 Bala (Ankara, central Turkey) earthquakes : a case study for strike-slip fault terminations

An intense seismic activity has been observed after the Bala (Ankara, NW central Turkey) earthquakes (30 July 2005: Mw=5.3, 20 December 2007: Mw=5.4, and 26 December 2007: Mw=5.3), continuing up to the present. The epicenters and the focal mechanism solutions of the earthquakes indicate that the rig...

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Detalles Bibliográficos
Autores: Esat, K., Çivgin, B., Kaypak, Bülent|||0000-0003-4650-9171, Isik, Veysel, Ecevitoglu, B., Seyitoglu, Gürol
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:117224
Acceso en línea:https://ddd.uab.cat/record/117224
https://dx.doi.org/urn:doi:10.1344/105.000002075
Access Level:acceso abierto
Palabra clave:Strike-slip faults
Fault terminations
Tuzgölü fault zone
Neotectonics
Bala earthquake
Anatolia
Descripción
Sumario:An intense seismic activity has been observed after the Bala (Ankara, NW central Turkey) earthquakes (30 July 2005: Mw=5.3, 20 December 2007: Mw=5.4, and 26 December 2007: Mw=5.3), continuing up to the present. The epicenters and the focal mechanism solutions of the earthquakes indicate that the right lateral strike-slip Afşar fault, trending N55-60°W, is responsible for the main shocks. The Afşar fault is thought to be the NW continuation of the Tuzgölü fault zone, which is one of the main neotectonic elements in central Anatolia. On the other hand, the aftershock distributions of the 2005 event have a NNE trend, and those of the 2007 event show a NW trending. Some focal mechanism solutions of the 2005 Bala earthquake aftershocks indicate normal and oblique normal faulting that corresponds to the NNE-trending Karakeçili fault. It seems that seismic activation of the NNE-trending Karakeçili fault was triggered by the 2005 main shock (Mw=5.3) that occurred on the NW-trending right lateral strike-slip Afşar fault. The overall neotectonic framework is that the northwestern edge of the Tuzgölü fault zone, represented by the Afşar fault in Bala, terminates in an extensional system represented by the oblique-slip Karakeçili fault.