Creating infrastructure for seismic microzonation by Geographical Information Systems (GIS): A case study in the North Anatolian Fault Zone (NAFZ) T. Turk a,n , U. G¨ um ¨ us -ay b , O. Tatar c a Department of Geomatics, Faculty of Engineering, Cumhuriyet University, 58140 Sivas, Turkey b Department of Geomatics, Faculty of Civil Engineering, Yildiz Technical University, 34220 Davutpas -a, Istanbul, Turkey c Department of Geology, Faculty of Engineering and Architecture, C - anakkale Onsekiz Mart University, 17020 C - anakkale, Turkey article info Article history: Received 18 February 2011 Received in revised form 4 October 2011 Accepted 6 October 2011 Available online 25 October 2011 Keywords: GIS North Anatolian Fault Zone Photogrammetry Seismic microzonation Spatiotemporal analysis abstract Although there are many studies for seismic microzonation in the literature, these studies have not covered the whole seismic microzonation processes. Moreover, they have not sufficiently focused on the important subjects, such as significance and use of aerial photos in seismic microzonation studies, data types used for seismic microzonation, and integrating these data by GIS. This study suggests a GIS-based model that can be used for all settlements that are at risk of natural disaster, with a view to taking necessary measures against such natural disasters (especially earthquakes). This model was applied so as to take the measures needed for the town of Erbaa located on the western part of the eastern segments of the North Anatolian Fault Zone (NAFZ), a settlement with earthquake risk on the NAFZ. During creation of the system, geological, geotechnical data and data produced from aerial photos were integrated and assessed on a GIS environment. The infrastructure for seismic microzonation was created using this model. The potential areas for soil liquefaction were detected in the study area. Thus, the results were produced to assist in seismic microzonation. & 2011 Elsevier Ltd. All rights reserved. 1. Introduction Humankind has experienced and been involved in problems caused by disasters since ancient times. As cities have expanded and become crowded, the impact of disasters on urban areas has increased accordingly. Losses of both lives and money have been incurred around the world due to natural disasters such as earthquakes, landslides, floods, etc. (Turk, 2009). The application of technology required to control the effects of natural hazards comprises three significant elements, such as prediction, mon- itoring and safeguarding (Alexander, 1995). In the recent years, different technologies have been developed showing possibilities for a wide range of disaster management and hazard mitigation (Yilmaz, 2009). GIS can be used as a tool to minimize the damage resulting from these disasters (Lee and Talib, 2005; K¨ ohler et al., 2006; Pal et al., 2007; Inel et al., 2007; Thierry et al., 2007; Lantada et al., 2007; Galderisi et al., 2008; Turk, 2009; Yilmaz, 2009; Mancini et al., 2010; Bednarik et al., 2010). Microzonation studies solve problems resulting from natural disasters such as earthquakes and landslides. It is highly difficult to perform such studies by means of classical methods. Therefore, a GIS is needed to respond to these questions accurately and quickly (Kolat et al., 2006; Kienzle et al., 2006; Nath, 2005; Papadimitriu et al., 2008; Turk, 2009). In recent years, GIS has emerged to be a powerful computer-based technique that inte- grates spatial analysis, database management, and geographical visualization capabilities. For geotechnical purposes, GIS-based information systems have been developed and used to forecast and plan for natural hazards such as landslides or earthquakes (Kiremidjian, 1997; Anastasiadis et al., 2001). Particularly, in geotechnical earthquake engineering, there has been a number of research studies on GIS technology. This technology has been widely used in increasing numbers of seismic zonations for the prediction of earthquake-induced hazards (Kolat et al., 2006; Sun et al., 2008; Grasso and Maugeri, 2009). Reliable data is the most important component in GIS studies. They are obtained from different geographical data sources, such as aerial photos, satellite images, laser scanning, the Global Positioning System (GPS), terrestrial measuring, and digitizing from existing maps. Since aerial photos and satellite images allow quick, accurate, and up-to-date geographical data, they are more preferred than other geographical data sources. The data-collection process is one Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/cageo Computers & Geosciences 0098-3004/$ - see front matter & 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.cageo.2011.10.006 n Corresponding author. Tel.: þ90 346 219 10 10x24 38; fax: þ90 346 219 11 65. E-mail address: tarikturk@gmail.com (T. Turk). Computers & Geosciences 43 (2012) 167–176