Summary Tectonic geomorphology studies provide an understanding of active tectonics in a region. The Simav half-graben lies within the western part of the Anatolian Plate, characterized by normal faulting and prominent topography due to regional N-NE extensional tectonics. We computed six geomorphic indices for 101 drainage basins along the study area. Hi values show relatively higher amounts in the southern section and are related to the neotectonic activity of the Sındırgı-Sinanpaşa Fault Zone. Sl anomalies mainly refer to the knickpoints/knickzones caused by faulting and are commonly seen in the southern section of the study area. The high values of Ksn highlight the effect of tectonic processes and indicate rapid uplift rates. According to Vf results, most of the V-shaped values are observed in the southern and northeastern parts of the Simav half-graben. Af and Bs results suggest that high tilting events and elongated basins primarily locate along the Çaysimav and Naşa Fault Zones. The quantitative geomorphic analyses suggest that the Simav half-graben is tectonically active during the Pleistocene and Holocene epoch and probably up to the present, where the landscape has developed in tectonicdominated conditions rather than erosional processes.

Summary Mapping geohazards of various scales, such as earthquakes and landslides, by Interferometric Synthetic Aperture Radar (InSAR) techniques, has been widely used in recent years. Monitoring landslide deformation with InSAR can help us better understand the mass propagation and motion evolution in space and time, respectively, and the driving factors. Saein landslide event in 2005 destroyed at least 350 m of Ardebil-Sarab roadway and power lines. The maximum horizontal and vertical displacement during the landslide were 10–20 m and 7–10 m, respectively. We selected three monitoring points in the study area to perform time-series analysis using the Sentinel-1 wide swath data acquired from 01.01.2019 to 08.04.2021 in descending orbit. In P-1 and P-3, creeping rates vary from +10.5 ± 0.5 to +22.0 ± 1.0 mm/yr and 6.1 ± 0.8 to 24.0 ± 2.0 mm/yr, respectively. Whereas the maximum creeping rates in P-2 are +7.0 ± 1.0 to −40 ± 2.0 mm/yr. The average velocity in P-1, P-2, and P-3 are 1.70, -16.5, and 3.20 mm/yr, respectively. Our results indicate that the existence of crushed zones in volcano-clastic rocks and volcanogenic sedimentary units due to the activity of the Yamchi Fault Zone has reduced stability along the slopes and accelerated creep movements.

Summary Flood disasters caused by regional or local heavy rainfalls have become one of the most severe types of climaterelated natural disasters. Urban areas in Turkey frequently suffer from floods, which are common climate-related disasters. For example, heavy rainfall for three days in Kastamonu province, northern Turkey, caused a catastrophic flood event on August 11, 2021 in Bozkurt district. At least 71 people have died, many houses and shops were severely damaged, two apartments have collapsed, and the flood dragged many cars. In this study, an automatic change detection processing for rapid flood mapping in Sentinel-2 data by analyzing the Natural Color and Normalized Difference Water Index (NDWI) images over the Bozkurt district and Ezine Valley demonstrate the effectiveness and efficiency of the remote sensing data. Natural Color images emphasized the flooding impact in Bozkurt district and transportation of mudflows through the Ezine Valley into the sea. Additionally, evaluating the NDWI data shows that approximately 1.61 km2 drought by severe flood event caused by heavy rainfall in August 2021. Bozkurt flood and similar disasters draw attention to the fact that weather is becoming more severe and more frequent due to anthropogenic global climate change.

Summary Interferometric Synthetic Aperture Radar (InSAR) data have shown their potential for studying moderate-size earthquake events. The InSAR approach detects surface displacements in the LOS direction between satellite acquisitions before and after an earthquake and is used to extract earthquake fault parameters. The Zagros Mountains mark the western and southwest sides of the Iranian Plateau and accommodate the total shortening between Central Iran and Arabia by involving active folding and thrust faulting parallel to the belt. April 18, 2021, the Bandar Ganaveh earthquake (Mw: 5.8) originated at a relatively shallow depth of approximately 9–20 km and produced a strong ground shake that mainly affected the Bushehr province and its surroundings with moderate to low damages in buildings of rural areas. The interferograms obtained from our InSAR analysis reveal significant surface deformation in the absence of clear signals of surface rupture. Interferogram patterns are also consistent with the orientation of the Zagros Mountain Front Fault. The retrieved InSAR displacement map indicates the maximum positive displacement value or uplift of 18 cm and the maximum negative displacement value or subsidence of 17 cm in the different blocks of the preferred fault trace in agreement with a thrust faulting mechanism.

Summary Earthquake is natural hazards which affect negatively human life. To understand earthquakes and reduce its damages, it is necessary to determine active faults and reveal their nature. Determining and understanding of active faults is essential to paleoseismological studies. The aim of paleoseismological studies is to specify the characteristics and dating of historical and prehistorical earthquakes and estimate probability and magnitude of future earthquakes. East Anatolian Fault Zone (EAFZ) with a number of different segments is among the active fault zones in the world. The Erkenek and Gölbaşı segments of EAFZ has typical morphotectonic features of strike-slip fault zones such as deflected stream channels, shutter ridges, linear valleys, and sag ponds. Our paleoseismological studies exhibit historical/prehistorical earthquake events and related with surface ruptures. We have also calculated statistical results of probabilistic analysis using instrumental earthquakes data along the Erkenek and Gölbaşı segments for estimating probable occurrence and recurrence interval period for earthquakes with magnitudes of 4.5–6.5. Accordingly, recurrence interval for a probable earthquake with a magnitude of 6.5 on the Erkenek and Gölbaşı segment is about 194–252 years.

Summary NW Iran is among most interesting and complex area within Arabian-Eurasia collision zone. Historical and instrumental records in this region indicate major tectonic structures which can produce serious seismic hazards. The North Bozgush Fault Zone consists of several parallel and sub-parallel faults which have developed in right lateral strike slip system with reverse component. We have run two geomorphometric indices to evaluate relative uplift rate along NBFZ; which are valley floor width to height ratio and mountain front sinuosity index indices. Also, we have used VF values versus Smf values to demonstrate relative uplift rate changes through the North Bozgush Fault Zone. The results of the geomorphometric analysis show that tectonic activity along the North Bozgush Fault Zone decreases significantly from west to the east. Measured relative uplift rates show that uplift rate is higher than 0.5 mm/yr in western and central parts, while this rate decreases in eastern part which is between 0.5 and 0.05 mm/yr. Seismic records data also support these results.

NW Iran, including the study area is one of the seismically active regions between Zagros Thrust Belt at the south and Caucasus at the north. In this region, an area known as Alborz-Azerbaijan zone includes many significant active fault zones. Not only large magnitude historical earthquakes (Ms>7), but also 1997 Ardebil (Mw 6.1) and 2012 Ahar-Varzagan (Mw 6.4) earthquakes reveal that the region is seismically active. The North Bozgush Fault Zone in this region has tens of kilometers in length and hundreds of meters in width. The zone has produced some large and destructive earthquakes.In this study five different study domains have been chosen along the North Bozgush Fault Zone. These are Sherbian, Danbaran, Anakiz, Damencan and Abgerm regions, respectively. The North Bozgush Fault Zone affects the Cenozoic units. Along this zone Eocene units thrusted over Miocene and/or Plio-Quaternary sedimentary units. The zone is mainly characterized by strike-slip faults with reverse component and reverse faults. Reverse faults striking N55o-85oE and dip of 40o-50o to the SW while strike-slip faults show right lateral slip with N50o-85oW and N60o-80oE directions.Our structural data analysis indicates that the North Bozgush Fault Zone shows σ1 principal stress (compression) with NW-SE direction and σ3 principal stress (extension) with NE-SW direction. The axis direction of σ2 principal stress is vertical and the stress ratio (R) is 0.12. These results suggest that the tectonic regime along the North Bozgush Fault Zone is transpressive. Fault slip analysis results are compatible with stress directions and GPS velocity results for NW Iran. Western part of the Bozgush Mountains is bounded with the Tabriz Fault Zone. Our field studies suggest that there is a genetic relationship between the North Bozgush Fault Zone and the Tabriz Fault Zone

Savcili fay zonu (SFZ), Orta Anadolu’da 70 km uzunluk ve 10 kmgenislikte, birbirine paralel yari-paralel pek cok faydan olusan bir zondur.Zonun ana litolojisini temel kayalari ve ortu birimleri olusturmaktadir. Zonicinde inceleme sahasi olarak secilen iki alan (Alan 1, Alan 2) faylanmanintanimsal ve kinematigine yonelik bilgiler sunar. Bu alanlarda fay yuzeyleriboyunca metamorfikler, Eosen yasli kirintili birimler uzerine, granitoyidlerdemetamorfitler uzerine itilmislerdir. Savcili fay zonu’nu temsil edenbindirme/ters faylarin egemen dogrultusu KB-GD olup GB’ya egimlidir. KD-GBdogrultulu ve GD’ya egimli duzlemlerde bulunmaktadir.Her bir fay, zon tanimlamasi (kataklastik zon) icerisindecekirdek ve hasar zonu olarak ayirt edilmistir. Bu zonlarda, cekirdek ozelliklekataklasit gibi fay kayalari ile temsil olurken hasar zonu bres, kataklasitturu fay kayalari, yaygin kiriklanmalar, kivrimlanmalar ve mineral dolguludamarlar ile temsil olur. Fay yuzeyi analizleri inceleme alaninda faylarinegemen olarak guneydogudan kuzeybatiya bir hareketin, az oranda yaklasik guneydenkuzeye bir hareketin urunu oldugunu ortaya koyar. Paleostres analizi bufaylarin bugunku konumlarina gore olasi σ1, σ2, σ3 anastres (gerilme) yonlerini 040/K220B, 010/K680Dve 860/G180D olarak verir. Bolgedeki fay yuzeyleri mm-cmolcekli kinematik belirtecler (basamaklar, kiriklar, egimlenmis duzlemsel yapidizileri, asimetrik cukurlar) icerir. Bu belirteclerin ortaya koydugu makaslamaanlami yukaridaki hareket yonlerini destekler konumdadir.Bu calisma ile elde edilen veriler, Savcili fay zonunun yerinsig derinliklerinde, gevrek deformasyon kosullarinda yaklasik kuzey-guneyyonelimli bir sikisma sonucu olustuguna isaret eder.Abstract The Savcili fault zone (SFZ), located in the centralAnatolia, has a length of about 70 km and a width of about 10 km, and consistsof a numerous parallel to sub-parallel faults. Basement rocks and cover rocksconstitute main lithologies in the zone. Two typical areas (Area 1, Area 2) chosenas a study area within the zone include descriptive and kinematiccharacteristics of faulting. Along the fault surfaces in these areas, themetamorphites were settled on Eocene detritic sedimentary units, and thegranitoids were moved on the metamorphic rocks. These thrust/reverse faultswithin the Savcili fault zone are mainly NW-striking and SW-dipping; there arealso fault surfaces NE-striking and SE-dipping.Each faults in these areas represent fault zones consist ofcore and damage zones. While the core is characterized by fault rocks, such ascataclasites and gauges, the damage zones are represented by fault rocks(breccias, cataclasites), pervasive fracturing, faulting and mineral-filledveins in these zones. Fault surface analyses indicate that the direction ofmovement along these faults occurred mainly from southeast to northwest, andlesser amount of movements occurred approximately from south to north.Paleostress analyses display that the orientation of main stresses, σ1,σ2 and σ3 are 040/N220W, 010/N680Eand 860/S180E, respectively. Fault surfaces include mm-to cm-scale kinematic indicators (e.g. steps, fractures, trains of inclinedplanar structures and asymmetric cavities) and display sense of shearing, whichsupport direction of movement along these faults mentioned above.All these data obtained from study area suggest that theSavcili fault zone occured in shallow crustal depths, under brittle deformationconditions; yet the zone was developed under approximately north-south regionalcompressional stress.