Slip deficit along Major Seismic Gaps in Turkey

Project Manager: Asst. Prof. Dr. Fatih BULUT

Project Code: 14453

Project Start Date: 2018

Project Budget: 170 000 TL

Abstract:

Slip deficit and its interaction with the earthquake activity will be investigated along major seismic gaps in Turkey using inter-seismic period Global Positioning System (GPS) measurements and refined earthquake catalogues. Geodetic database consists of more than thousands of GPS stations, which are uniformly integrated. Earthquake database consists of tens of thousands of micro-earthquakes recorded by several hundreds of seismic stations operated mainly by Kandilli Observatory and Earthquake Research Institute (KOERI) and Prime Ministry Disaster and Emergency Management Authority (AFAD). In this frame, along-fault distribution of slip deficit will be compared with the micro-seismicity as well as available slip distribution models of the past M>6.0 earthquakes. Historical earthquakes will be used to verify annual slip rates of the investigated fault segments. Comparison between inter-seismic slip deficit and available co-seismic slip distribution models will verify whether GPS data can forecast slip distribution of large earthquakes. Furthermore, comparison between inter-seismic slip deficit and available refined earthquake catalog will verify creeping and locked fault patches along the fault segments, which are expected to accommodate large earthquakes in the future. Finally, developed slip deficit models will be used to forecast co-seismic slip of the expected large earthquakes.

Determination of Strain Rates and Velocity Field in Geodetic Control Networks Along Western North Anatolian Fault by GPS

Project Manager: Prof. Dr. Haluk Özener

Project Code: 7506

Project Start Date: 2013

Project Budget: 36000 TL

Abstract:
Since 1970s, geodetic studies have been carried out for detecting crustal movements along North Anatolian Fault Zone in Turkey. Geodesy Department of Kandilli Observatory and Earthquake Research Institute at Boğaziçi University has conducted20 scientific projects with support of BU-Scientific Research Projects Fund. In this context, three geodetic control networks wereinstalled in the regions having significant seismic hazard. One of them is located in Iznik, an area of low seismicty; the other one is Sapanca which is the most seismically active region; and the third network is located in Akyazı where the fault splays in two branches. These networks have been measured by conventional geodetic techniques, then GPS technique has been applied and they have been connected to regional geodynamic GPS Networks. These networks have importance in contributing to theassesment of seismic hazard in the region inferred from episodic GPS observations.
In order to monitor tectonic deformation in other regions with high earthquake hazard such as East Anatolia (16-point network, 2003-2006) and Aegean Region (16-point network, 2009-2012), the Department has installed geodetic networks and organized GPS campaigns. Furthermore, two additional geodetic networks has been surveying by GPS technique for several years. These networks are Ismetpasa (estalished by ITU in 1981) and Iznik-HGK (established by ITU and GCM in 1941) networks.
GPS technique plays a very important role in understanding of earthquake mechanism in each phase of seismic cycle, i.e., the pre-, co- and postseismic stage. Co-seismic movements depend on the amount of slip and the depth of the earthquake. Near-field GPS observations can be used to obtain strain accumulating across locked faults and can therefore help us to determine the seismic potential of the region of interest. It is also necessary to link the short-term geodetic observations to the medium and long-term trends.In the scope of the proposed project, it is aimed to ensure the continuity of the measurements, examine the change in the magnitude of the velocity vectors, and identify the current velocity field and strain accumulation through these geodetic networks

Validation of aseismic surface creep along the 1999 Izmit rupture, using GPS and LIDAR measurements

Project Manager: Prof. Dr. Semih Ergintav

Project Code: 7685

Project Start Date: October 8,.2013

Project Budget: 36 122 TL

Abstract:
Based on time series analysis of the radar images of the European Space Agency (ESA), GPS measurements and field observations, researchers showed that the central section of the 1999 Izmit break is creeping slowly. Creeping should be confirmed by detailed geodetic measurements. The scope of this project is to revisit the sites and to record the deformations on the man-made structures, using GPS and LIDAR. Data, total offsets, and deformations archived for long-term new scientific projects.

Determination of Slip Rates of East Anatolian Fault System with Geodetic Methods

Project Manager: Prof. Dr. Bahadır Aktug

Project Code: 7020

Project Start Date: 2012

Project Budget: 34500 TL

Abstract:
East Anatolian Fault System (EAFS) is the second most important fault system in Turkey following North Anatolian Fault System (NAFS). However, the fault slip rates on EAFS were not studied sufficiently. This is possibly due to the relatively lower seismicity and slower slip rates of EAFS with respect of NAFS. On the other hand, historical records show that EAFS has the potential to produce large earthquakes. The GPS studies on EAFS are usually at local scale anda are limited in number. In those studies, it has not been possible to determine slip rates of the different segments of EAFS due to the sparse distribution of geodetic stations. In this respect, determination of fault slip rates of EAFS is one of the areas which requires further investigation. The proposed study comprises the precise determination of the fault slip rates of EAFS with geodetic observations which has a high spatial resolution, better geometric configuration and precision. The determination of the slip rates of EAFS is equally important to understand the kinematics of Anatolian plate. In this Project, it is proposed that the geodetic observations which will be collected in a larger area covering EAFS and will be analyzed to determine the fault-parallel and fault-normal components of the slip rates precisely. The raw GPS data to be obtained in the proposed Project will be analyzed and will be compared to the studies in the literatüre to determine the fault slip rates of EAFS and the current strain accumulation as well.