Ergin Tari

Active tectonics of the Black Sea with GPS

The Black Sea occurs within the Anatolian sector of the Alpine-Himalayan orogenic system. In this region northward moving African and Arabian plates collide with Eurasian plate. From this collision the Anatolian block moves westward with a rotation pole located approximately north of Sinai peninsula. Tectonic styles and rates in the circum Black Sea and along the Crimea have been poorly known. A GPS project was initiated in 1995 with the collaboration between Istanbul Technical University, MIT and Joint Institute of Physics of the Earth (Moscow). To carry out the project, two GPS campaigns were performed. Data have been analysed by the well-known GPS processing program, GAMIT which is a comprehensive GPS analysis package, and GLOBK, a Kalman filter. This paper presents the important outputs from the two GPS campaigns and gives suggestions for the future investigations in the region. The important outcome of the project is that the N-S motions along mostly in the Eastern margin of the Black Sea are in a few mm/year, such as SINO, a southern coast site, with a rate of 1.4 ± 1.7 mm/year in NW direction, and GELE, a northern coast site, with a rate of 2.2 ± 2.8 mm/year in SE direction, while the velocities in the Anatolian region are approximately 10–20 ± 3–5 mm/year.

The August 17 Kocaeli and the November 12 Duzce earthquakes in Turkey

Two devastating earthquakes occurred in Turkey, one on August 17 and the other on November 12, 1999. The magnitudes were 7.4 and 7.2 respectively. The epicenter of the first earthquake was located near Golcuk, a town near Kocaeli province, 110km from Istanbul. The epicenter of the second earthquake was in Duzce, 150 km from Istanbul. The first earthquake occurred after midnight and killed more than 15000 people. This number is obtained from an official report, while the actual deaths are expected to be more than 20,000. The earthquake was a nightmare for the whole country, and affected almost 10 cities including Istanbul. The second earthquake occurred on November 12 in the early evening, and killed about 1000 people. The affected area from the two earthquakes has a population of about 20 million, which is one third of the whole population of the country, and almost half of the Turkish economical infrastructures is located in this region. This paper gives an overview of the two devastating earthquakes, including geological background of the region, economical impacts and degrees of damages on different aspects.

Transition Curve Modeling with Kinematical Properties: Research on Log-Aesthetic Curves

Log-aesthetic curves (LACs), which are generally used in industrial design for aesthetic shape modeling, are examined for implementation as transition curves despite their non-trivial representation in terms of incomplete gamma functions, or Fresnel integrals which appear in the parametric equations of a certain spirals. The family of log-aesthetic curves includes well-known spirals as Euler, Nielsen, logarithmic spiral, and involutes of a circle. The horizontal geometry of the route can contain classical transition curves, which are formed by transition curve-circular arc-transition curves. In order to compare the examined family of log-aesthetic transition curves with the classical transition curve in terms of vehicle-road kinematics, the curvature and superelevation functions are derived, and functions of lateral change of acceleration (LCA) curves are obtained and illustrated graphically using a constant motion model. The discontinuities in the form of jumps in the graphs of the lateral change of acce...

GPS Measurements along the North Anatolian Fault Zone on the Mid-Anatolia Segment

The North Anatolian Fault (NAF) is one of the longest active strike slip systems. Slip rate of the NAF was estimated from the GPS data as 20–24mm/yr approximately from previous studies. One of the important features of the NAF is seen in the central part. Here NAF consists of southward splitting concave branches. These splines generally have right-lateral slip and can be compared with Riedel fractures. The important splays are Sungurlu, Merzifon and Lacin faults. A new project “Determination of Kinematics along the North Anatolian Fault Branch between Ladik and Ilgaz with GPS Measurements”, founded by The Scientific and Technical Research Council of Turkey (TUBITAK) and Istanbul Technical University (ITU) Research Fund has been carried out in order to determine the magnitude and direction of the block movements in the region by using GPS since 2001. The knowledge about the neotectonics of the region with the contributions of geology and seismology after the GPS campaigns is expected to provide further information on the assessment of the earthquake potential.

Monitoring of Deformations Along Fethiye-Burdur Fault Zone (Turkey) with GPS

Afyonkarahisar, Burdur and Fethiye region, southwest of Turkey is located on a tectonically active area. According to the historical recordings, the region was destructed by earthquakes many times. Since the beginning of the 20th century, more than 35 earthquakes with magnitudes bigger than 4 occurred in Afyonkarahisar region. Seven earthquakes recorded over the last 90 years in the region between Burdur and Fethiye whose magnitudes are between 5.0 and 7.0. This new project “Monitoring of Deformations Along Fethiye-Burdur Fault Zone With GPS”, is founded by The Scientific and Technical Research Council of Turkey (TUBITAK), Istanbul Technical University (ITU), Karadeniz Technical University (KTU) and Afyon Kocatepe University (AKU). The aim of the project is to determine strain accumulation of the study area.