[H-DS08] 人間環境と災害リスク

[HDS08-P07] Utilization of a Complementary Monitoring System on North Anatolian Fault of Turkiye: MARTEST project

*AHMET ANIL DINDAR¹、AITARO KATO²、YOSHIYUKI KANEDA³、BULENT AKBAS¹、SELCUK TOPRAK¹、CEREN OZER SOZDINLER¹ (1.GEBZE TECHNICAL UNIVERSITY、2.UNIVERSITY OF TOKYO、3.KAGAWA UNIVERSITY)

キーワード：Earth observation, Digiral Acoustic Sensing, GNSS, InSAR, North Anatolian Fault- East Marmara

Tectonic activities in Anatolia plate which covers entire Turkiye have always been striking for ages. Historical and instrumental recordings display the destruction of potential faults lines on east, north and west sides of Anatolia, Turkiye. Unfortunately, the last 6 major earthquakes with magnitudes higher than 7.0, namely 1999 Mw7.4 Izmit, 1999 Mw7.2 Duzce, 2011 Mw 7.2 Van, 2020 Mw7.0 Samos and, most recent, 2023 Mw7.7 and 7.6 Kahramanmaras, evidently prove that a complementary monitoring system consist of seismological, geodetic, and high-end electronic sensors is indisputable necessary in fulfilling the disaster resilient society goal of Turkiye. Considering the vast size of affected area covering 10 provinces from the most recent 2023 Kahramanmaras earthquakes claimed more than 35,000 lives and huge economic loss, cutting-edge methodologies out of technological developments should be fostered into risk mitigation policies. Recent developments in technology made the earth observations approaches incredible high-fidelity and gained broad capabilities those were not even arguable in the last decade. Among these developments, Distributed Acoustic Sensing (DAS) through the fiber optic cables coupled to the ground is accounted as high-end observation methodology utilized in few locations around the world. DAS technology has been used in the border crossing protection. However, its ability in sensing the ground disturbance along the length of well-installed FO cable laying either on the land or on the ocean bottom has revealed new opportunities in earth observation of slope-stability measurements, river levee integrity, railway operations and eventually seismic tomography in tectonic regions. Even though the process of the data collected require use of sophisticated methodologies based on artificial intelligence with excessive computational resources, great ability to sense large areas’ vibration mesmerize the future studies in understanding the faults in complicated topography. East side of Marmara where 1999 Mw7.4 Izmit earthquake occurred has such an intricate topography because the North Anatolian Fault goes into the sea after crossing hundreds of kilometers in the Anatolian plate. Use of geodetic techniques such GNSS measurement and InSAR imagery fails in the monitoring the crustal deformation due to the sea surface reflection. Thus, process of DAS measurement from the FO cables on Marmara seabed with complementary OBS and geodetic timeseries could be a viable approach in monitoring an active segment of North Anatolian Fault an apparent hazard to province of Istanbul. Following the success of MARDIM project in west Marmara Sea between the years of 2013-2018, a new project “MARTEST - Establishment of a Research and Education Complex for Developing Disaster-Resilient Societies” initiated in April 1^st, 2023 by Japanese and Turkish research institutions under the SATREPS program cordially funded by JICA and JST. In the scope of MARTEST project, state-of-art application of DAS measurement with the complementary use seismological and geodetic resources will be conducted by Japanese and Turkish researchers. The results of the planned monitoring system would significantly contribute in enhancing the disaster resilience of the societies exposed to seismic hazards.