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The main objective of this study is to analyze geomorphic landforms and quantitatively measure various geomorphic parameters to investigate the relative tectonic activity, vertical slip rate, and uplift rate of the Simav Fault. The Simav Fault, which is ~25 km long and morphologically composed of five mountain fronts forms the NW section of the ~400 km long Afyon–Simav Fault System (ASFS) within the Western Anatolian Graben System (WAGS). The mountain front sinuosity (Smf) and valley floor width-to-height ratio (Vf) hypsometric integral (HI) and hypsometric curve (HC), asymmetry factor (AF), drainage basin shape (Bs) and stream length gradient index (SL) indices were calculated to determine the relative tectonic activity in the mountain fronts and drainage areas bounded by the Simav Fault. The spatial distribution of the index of relative tectonic activity (Iat) was revealed using the combination of the obtained morphometric analysis results. Geomorphic indices indicated that high tectonic activity is intensified along the entire Simav Fault, which has a normal fault component, whereas medium and low tectonic activity is calculated on faults with strike-slip components. The highest vertical slip rates obtained using the slopes of the facets were calculated as 0.19 mm/y for MF-2 and MF-4 and the lowest as 0.07 mm/y for MF-5. Furthermore, using the heights of the facets and vertical slip rates, the youngest mountain front was found to be MF-2 (8.17 ma) and the oldest mountain front was found to be MF-5 (14.71 ma). The obtained vertical slip rate and age data showed that the mountain front in the central part of the Simav Fault is younger with having higher vertical slip rate. According to this study, the Simav Fault has played a decisive role in the evolvement of the actual morphology in the study area, has produced moderate earthquakes in the last century, and is thought to have the potential to produce larger earthquakes in the future (up to M6.71). It is important for the region to investigate and reveal the earthquake potential of this fault through paleoseismic studies.

30 Ekim 2020 (Mw=6,6) Sisam depremi, İzmir ilinde aletsel dönemde en fazla can ve malkaybına yol açmış deprem olarak kayıtlara geçmiştir. Bu depremde 117 kişi binaların göçmesinedeniyle can vermiş ve 1 kişi ise, depremden sonra Sığacık Körfezinde yaşanan tsunami nedeniylehayatını kaybetmiştir. Sisam Adası’nı kuzeyden sınırlayan denizaltındaki Sisam Fayı’nın kırılmasıylagelişen bu depremin yanı sıra, İzmir il sınırları içinde meydana gelen 1928 Torbalı ve 1949 Dikilidepremleri, can ve mal kaybına yol açan diğer aletsel dönem depremleridir. Tarihsel dönemde ise, çokdaha yıkıcı depremlerin geliştiği deprem kataloglarından bilinmektedir. Fakat bu depremlerin hangifaylardan kaynaklandığı konusundaki bilgilerimiz yok denecek kadar azdır. Bu boşluğu doldurmakiçin TÜBİTAK’a sunulan ilk proje 2021 yılında tamamlanmış, akabinde aynı yıl kabul edilen ikinciproje ise devam etmektedir. İlk projede İzmir Fayı, Tuzla Fayı, Gülbahçe Fayı, Yağcılar Fayı veSeferihisar Fayı üzerinde hendek tabanlı paleosismolojik çalışmalar yapılmış ve bu çalışmalarsonucunda, fayların deprem tekrarlama aralıkları, son ürettikleri depremler ve bu depremlerden sonrageçen süreler saptanmıştır.Çalışmadan saptanan bulgular, MS 177/178, MS 1039/1040, MS 1056, MS 1389 ve MS 1688yıllarında meydana gelen depremlerin bahsi geçen faylar tarafından oluşturulduğunu göstermektedir.Buna ek olarak sonuçlar MS 1389 depreminin Gülbahçe Fayı’ndan, MS 177/178 depreminin TuzlaFayı’ndan, MS 1039/1040 depreminin Yağcılar Fayı’ndan ve 1688 depreminin İzmir Fayı’ndankaynaklandığına işaret etmektedir. Buna göre, Gülbahçe Fayı 632, Yağcılar Fayı 982, İzmir Fayı 334,Tuzla Fayı ise 1843 yıldır yıkıcı deprem üretmemektedir. Bu sonuçlar incelenen fayların birbirinitetikleyecek şekilde depremler ürettiğini ve bölgede ortalama 300 yılda bir yıkıcı deprem olduğunugöstermektedir.14

Soma-Kırkağaç Fayı’nda gerçekleştirilen paleosismolojik amaçlı hendek kazılarında, toplanan örneklerin su içeriği değişiminin Lüminesans tarihlendirmeye (OSL ve TL) etkisinin araştırıldığı bu çalışmada, kolüvyal çökellerin su içeriklerine bağlı olarak yıllık dozu önemli boyutta etkilediği, dolayısıyla analiz edilecek örneğin tarihini %16 oranında değiştirdiği saptanmıştır. Bu kapsamda OSL tarihlendirme için, Soma-Kırkağaç Fayı üzerinde açılan hendekteki KF8 örneğine ait doygun ve doğal ortamdaki su miktarlarının değişkenliğinin yıllık doz ve doğrudan yaşa etkisi iki farklı senaryoda tartışılmıştır. Yapılan çalışmada, örneklerin oluşumunda derinlik, tane boyu, sıkışma ve iklimsel özelliklerin de etkileri olduğundan dolayı oluşum anındaki iklim şartları da göz önünde bulundurularak önce doğal su içeriği ve sonra doygun su içeriği baz alınmıştır. Ağustos ayında toplanan 9 adet örnek üzerinde yapılan çalışmalarda, KF8 örneğine ait tarih, ilk senaryoya göre 17,47±2,71 bin yıl saptanmıştır. İkinci senaryoda vurgulanan doygun su parametrelerinin düzeltme katsayısına göre tek başına esas alındığında ise örneğin yaşı 20,19±3,11 bin yıl olarak elde edilmiştir. Sonuç olarak, saptanacak yaşların hassas olarak elde edilebilmesi için, su içeriklerinin literatürde verilen katsayı ile elde edilmesi yerine, çalışılan bölgeye ait oluşturulması gereken detaylı iklimsel özelliklere göre saptanması ve tarihlendirmeyi denetleyecek farklı bir metodolojinin de uygulanması gerekliliğini ortaya çıkarmaktadır., To reveal the effect of the change in water content for luminescence dating (OSL and TL), in this study, nine samples were collected from the paleoseismological trench wall on the Soma-Kırkağaç fault. The results indicated that the dose rate significantly is affected by colluvial deposits having different water content, which signifies it was determined that the date of the level be date changed by 16%. In this context, the effects of the variability of the saturated and the natural water content for the KF8 sample on the dose rate and luminescence age were discussed in two different scenarios. In the study, since depth, grain size, compaction, and climatic characteristics of the region are also effective in the formation of the colluvial samples in both scenarios, in the light of the paleoclimatic conditions, the natural and the saturated water content were examined, respectively. According to the first scenario, the KF8 samples dated 17.47±2.71 ka. However, in the second scenario, it was found as 20.19±3.11 ka taken into correction factor regarding the saturated water content. As a result, it is necessary to determine the water contents according to the detailed climatic characteristics of the study area, instead of using the coefficient given in the literature. Moreover, it is strongly recommended here that a different dating methodology should be performed to determine the more realistic and the more accurate ages in paleoseismological studies.

Kusadasi Bay, which is controlled by active normal faults, is located in an evolving graben in the west of the Western Anatolian Extension System. Gumuldur Fault (GF), which restricts Kusadasi Bay to the north, has approximately 30 km long, fragmented structure between Urkmez and Ahmetbeyli. GF, which strikes N (50 degrees-55 degrees) W direction, forms a sharp morphological escarpment between Urkmez and Ahmetbeyli starting from Paleozoic basement rocks to Quaternary alluvium units. The dip angle of the fault planes increases to the west (40 degrees-85 degrees SW), and the fault is a dip-slip active normal fault with convex structure and geometry toward the northeast. To unravel the Quaternary activity of Gumuldur Fault and the evaluation of the regional uplift, morphometric and kinematic analysis was performed for the first time on the fault that includes well-preserved geomorphological markers. Quantitative measurement of morphometric indices such as mountain front sinuosity (S-mf: 1.13-1.56), valley floor width to height ratio (V-f : 0.10-1.00), percentage faceting L-f/L-s ([L: 4.75-88.35, S: 0.12-9.30]), asymmetry factor (AF: 19-78), basin shape geometry (B-s: 1.05-5.98), stream length gradient (Hack) index (SL: 25-6094.44), hypsometric curve and hypsometric integral (HI: 0.16-0.53) and rock strength and climate parameters indicate that the footwall of the GF has been uplifting toward the west with more than 0.5 mm per year. According to kinematic studies of the GF, which is geometrically composed of three parts, the region developed under the control of an extensional regime oriented NNE-SSW. If it is broken into seperate segments, it has the potential to produce earthquakes with a magnitude of 6.12, 6,45 and 5.78, respectively. If considered as a single segment, it has the potential to produce earthquakes with a magnitude of 6.81 in Kusadasi Bay. For this reason, trench-based paleoseismological studies are needed to reveal the past activity of Gumuldur Fault and to determine the seismic hazard level in the region.

The Eastern Pontides, which is the under transpressional deformation zone, is an active mountain belt in northern Turkey that has been uplifting at a rate of more than 0.5 mm/year, along with push-up geometry. This uplift is accommodated by the dip/oblique slip normal fault segments of an en-echelon geometry mountain front mapped here for the first time. According to our geological mapping studies, the Southeast Black Sea Fault zone is about 65 km total long and more than 1 km wide and comprises nine fault segments. In the kinematic analysis conducted along the fault zone, fault planes have dip angles between 60 degrees-90 degrees to the north. The measured fault planes have rake angles range from 32 degrees to 90 degrees. Our findings indicate that (i) the faulting observed in the mountain front of the Eastern Pontides, the crustal thickness has increased due to thrust component strike-slip faults formed in a compressive regime where sigma 1 was horizontal at the initially, as a result of this, sigma 1 which is the horizontal position went into a vertical position, and lastly the former weakness zones were re-activated as normal faults, (ii) this weakness is defined as an Southeast Black Sea Fault that produces earthquakes have resulted in surface rupture in the Quaternary and therefore this fault should be considered in the class of "Quaternary Fault" in Turkey's active fault maps.