Türkiye Jeoloji Bülteni

Paleoseismological Three Dimensional Virtual Photography Method, Case Study: Duru-2012 Trench, Tuz Gölü Fault Zone, Central Anatolia, Turkey

Abstract: Paleoseismology is an active tectonic discipline that tries to obtain information about the location, time andmagnitude of paleoearthquakes by using geological and geomorphological data. Paleoseismic trenchingis the most important method that is frequently used in paleoseismology and provides considerable data.One of the most important problems encountered especially in deep and benched paleoseismologicaltrench works is the visual representation of the trench stratigraphy and structure to the reader.In this paper, “Paleoseismological Three Dimensional Virtual Photography Method”, a new photographicmethod for paleoseismology, is presented with a case study. Paleoseismological Three Dimensional VirtualPhotography Method consists of four stages which are respectively: planning, photographing, stitchingand constraction of virtual tour.Paleoseismological Three Dimensional Virtual Photography Method has been applied for the first timeduring the paleoseismological studies carried out on the Tuz Gölü Fault Zone (Central Anatolia, Turkey).The Tuz Gölü Fault Zone (TGFZ) is one of the most important intra-continental active fault zones in theCentral Anatolian Region. TGFZ is an approximately 200 km-long, NW-SE trending, active normal faultzone with a right lateral strike-slip component. The Akhisar-Kılıç segment is one of the most importantsegments of TGFZ which is composed of fault segments parallel or sub-parallel to each other and withlengths varying between 9 and 33 km. In this study, a paleoseismic trench (Duru-2011) has been excavatedon the middle section of Akhisar-Kılıç segment.As a result of the evaluation carried out making use of paleoseismological criteria such as trenchmicrostratigraphy, geometry of fault colluvial wedge, upward termination of fault strands, and 14C agedata, three paleoseismic events were described within the Duru-2011, which occurred in the last 23 000years. On the other hand, in the last 10 500 years two paleoseismic events has been described within theanother paleoseismological study. Earthquake data collected from the two trenches on the same segmentwere evaluated by “fault window method”. And averagely earthquake recurrence period of Akhisar-Kılıçsegment was calculated as 10390 year. Short time (Late Pleistocene - Recent) annual vertical slip rate ofAkhisar-Kılıç segment was calculated as 0,034 mm/year. This value is well consistent with long term (LatePliocene) vertical geological slip rate (0,046 mm-year) of segment.