Observation of Central Marmara fault kinematics with GPS

Life is the most precious asset for man. Since the day he existed, he has developed many defensive mechanisms, both instinctual and logical, that have fought to preserve this most precious asset. These fights he has made are sometimes with his own race, sometimes with hunger and absence, sometimes with diseases, and sometimes with nature. Man can deal with hunger and poverty by producing, wars with his own race by making agreement, but can not agree with nature or imagine precisely when it will attack. Therefore, all natural phenomena and their unknowns causing the loss of life and property, especially the earthquake, were wondered and investigated. In the process up to now, human being has developed new theories about earthquakes, produced hypothesis, tried to identify the problems and updated the defense mechanism by producing solutions and updating them in parallel with the development of technology. In this context, firstly in 1912, the idea that the plates were moving slowly but constantly with the "Slippery of the Titans" was put forward, and then with "Plate Tectonics Theory" in the 1970s, the fact that these movements caused earthquakes. It is possible to observe these movements and demonstrate the accumulation of strains caused by movement. Firstly, thanks to terrestrial measurements made on the San Andreas fault in 1906, it was possible that these deposits could be put forward by geodetic methods. With the development of technology, terrestrial geodesy techniques has left its place to satellite geodesy techniques. Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) methods are mostly needed to determine the rotation and gravity parameters of earth, ocean loading displacements and large-scale plate movements. The complex structure of VLBI (Very Long Baseline Interferometry) and SLR (Satellite Laser Ranging) techniques makes the use of GPS technology, a relatively simpler system more convenient. GPS (Global Positioning System) which is very useful in terms of logistics, low cost and able to measure everywhere and every kind of weather conditions 24 hours, can eleminate the personal errors and most importantly a system in which any point position on the Earth can be determined instantaneously in review of plate movements has been the optimum solution. GPS which was based in 1960s was only used by the US Department of Defense for military purposes, and there was no civilian casualty. By the end of the 1980s, with the opening of civilian use, the development of this technology was accelerated and geodynamic engineering activities such as plate movements became indispensable. While military uses of the system are land, sea and air navigation, search-and-rescue, targeting, the civil uses are; geodetic and geodynamic measurements, cadastral measurements, kinematic GPS supported photogrammetric studies, vehicle tracking systems, development of Geographic Information System databases, hydrographic measurements. There are some random and systematic errors that affect the results obtained by various reasons during GPS measurements and these errors and deviations are being tried to be corrected during the evaluation. These are; satellite ephemeris errors which can be corrected by using precise orbital information, satellite-receiver time errors which can be corrected by double differences method, atmospheric faults which can be eliminated by using various models, multipath, which observing satellites at a certain elevation angle reduces the reflection effect. Just as it is in the whole world, the victory of the war with earthquake in our country is to be won, to reduce the destructive effects and increase the predictability. Especially considering the fact that our country is located on the Mediterranean-Himalayan belt, which is the most active earthquake belt, and that there are active faults NAF (North Anatolian Fault) and DAF (Eastern Anatolian Fault) that make up its tectonics, every research done is extremely important. The Anatolian Plate, which is on our country, is surrounded by the Eurasian Plate in the north, the African and Arabian Plates in the south, the Eastern Anatolia Blossom in the east and the Aegean Block in the west. The three major catastrophic earthquakes such as Erzincan, (Mw = 8), in 1939 Gölcük, (Mw=7.4)in 1999, and Düzce, (Mw=7.2) in the same year , caused many lives and property damage. The material and psychological repair of the damage lasted many years. KAF passes through the regions of Varto, Bingöl, Karlıova, Erzincan, Susehri, Reşadiye, Niksar, Erbaa, Ladik, Havza, Kamil, Kargı, İsmetpaşa Station, Gerede and Bolu in the east and cut Ilgaz Mountains between Bayırlı and Havza respectively. Later on in the west, along the Soğanlı Vadileri, Abant and Mudurnu streams, the NAF is divided into two main arteries: North and South. The arm extending to the south runs through Geyve-Mekece-Iznik, where it continues to Bandırma and then continues to the Aegean Sea following the Biga peninsula. Starting from the İzmit-Adapazarı corridor, the northern branch folds the Sea of Marmara and merges with the Ganos fault to reach Saros Gulf. On this route, the NAF threatens Istanbul, one of the most crowded cities in the world with over 15 million population, through the Central Marmara Segment, whereas the Prince Islands segment produces elastic deformation. Determination of the strain accumulated in this region the utmost importance for Turkey, sees a move made in the task of winning the war, which made each work with earthquake. In this study, seven continuously monitored GPS stations were installed with the contributions of Strasbourg and Hitit Universities under the leadership of ITU Geomatics Engineering Department, and the evaluation was taken between 8 August 2017 and 15 February 2018. In addition, 19 stations from IGS (International GPS Service) network, to increase the accuracy of the data evaluation process, 17 stations from CORS-TR (Continiously Operating Reference Station) network, 10 satations from ISKI-UKBS (Istanbul Water and Sewerage Administration) network and 4 stations from DOHAD (Nature Movement Research Association) network were included in the evaluation. All these datas were evaluated with GAMIT / GLOBK software after converting datas to RINEX (Receiver Independent Exchange Format). GAMIT module helps to determine atmospheric parameters, zenit delays, station coordinates, satellite and receiver clock errors. Then for all stations daily and yearly repeatabilities were produced. After this by using GLOBK, coordinate and speed information was obtained in ITRF (International Terrestrial Reference Frame) system. Thus, the kinematics of the Central Marmara Segment are intended to be monitored by continuous stations, as mentioned in previous studies.