Articles | Volume 10, issue 10
Nat. Hazards Earth Syst. Sci., 10, 2135–2143, 2010
Nat. Hazards Earth Syst. Sci., 10, 2135–2143, 2010

Research article 08 Oct 2010

Research article | 08 Oct 2010

Estimation of strain accumulation of densification network in Northern Marmara Region, Turkey

I. Deniz1 and H. Ozener2 I. Deniz and H. Ozener
  • 1Istanbul Technical University, Department of Geomatics Engineering, Istanbul, Turkey
  • 2Bogazici University, Kandilli Observatory and Earthquake Research Institute, Department of Geodesy, Istanbul, Turkey

Abstract. Strain analysis is one of the methods for the kinematic analysis of the repeated geodetic measurements. In order to derive strain accumulation in Marmara Region, different institutions carried out several Global Positioning System (GPS) campaigns in 1999 and 2006. The GPS campaigns were performed on the geodetic network which cover the provinces: Kirklareli, Tekirdag, Bursa, Bilecik and Adapazari. Then, the displacements of the network stations were estimated by means of analysing the GPS space geodetic measurements. For the assessment of the datum differences between 1999 and 2006 on the station coordinates, 3-D Helmert transformation was applied to the coordinates of each 1999 and 2006 datum. Then, a global test was introduced to determine the significant deformation which occurred in the geodetic GPS network. Strain accumulation with a finite element model was then computed. First, triangles were constructed for the whole network with the Delaunay method. Hereafter, strain parameters were calculated for each triangle. Maximum values of strain accumulation were found around the surroundings of Marmara Ereglisi and Izmit, whereas minimum values are around Istanbul.