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On November 14, 2016, the northeastern South Island of New Zealand was hit by the magnitude Mw 7.8 Kaikōura earthquake, which is characterized by the most complex rupturing mechanism ever recorded. The widespread landslides triggered by the earthquake make this event a great case study to revisit our current knowledge of earthquake-triggered landslides in terms of factors controlling the spatial distribution of landslides and the rapid assessment of geographic areas affected by widespread landsliding. Although the spatial and size distributions of landslides have already been investigated in the literature, a polygon-based co-seismic landslide inventory with landslide size information is still not available as of June 2021. To address this issue and leverage this large landslide event, we mapped 14,233 landslides over a total area of approximately 14,000 km2. We also identified 101 landslide dams and shared them all via an open-access repository. We examined the spatial distribution of co-seismic landslides in relation to lithologic units and seismic and morphometric characteristics. We analyzed the size statistics of these landslides in a comparative manner, by using the five largest co-seismic landslide inventories ever mapped (i.e., Chi-Chi, Denali, Wenchuan, Haiti, and Gorkha). We compared our inventory with respect to these five ones to answer the question of whether the landslides triggered by the 2016 Kaikōura earthquake are less numerous and/or share size characteristics similar to those of other strong co-seismic landslide events. Our findings show that the spatial distribution of the Kaikōura landslide event is not significantly different from those belonging to other extreme landslide events, but the average landslide size generated by the Kaikōura earthquake is relatively larger compared to some other large earthquakes (i.e., Wenchuan and Gorkha).

Microclimatic variations in semi-arid ecosystems can cause topographic asymmetry over geologic time scales due to uneven distribution of incoming solar radiation as a function of slope aspect. This phenomenon has long been recognized in geomorphology and has been studied primarily in catchments with high spatial heterogeneity in climate forcing and underlying lithology. Due to fluctuations in prevailing climate and lithological differences in the studied catchments, the formation age and size of the catchments add another level of complexity and uncertainty. Due to their small size, uniform lithology, well-constrained initial morphology, and relatively young age, cinder cones are natural laboratories for better understanding the eco-hydro-geomorphic evolution caused by nonlinear interactions between vegetation, climate, and soil. The Sandal Divlit cinder cone located in the Kula volcanic field, western Turkey, is an inactive volcano and formed in the last stage of volcanism in the region. The climax vegetation in the primary succession following the volcanic eruption can be seen on north-facing slopes with trees. North-facing slopes have deeper soils than south-facing slopes, which have sparsely herbaceous plants and shrubs and thin, weakly developed soils. Airborne-LiDAR surveys and the digital elevation models having 5 m and 12.5 m spatial resolution were used to analyze the geomorphic descriptors and canopy structure of the cone as a function of aspect. In the summer and winter seasons, the surface temperatures of the cone were measured using a thermal-imaging drone. The results show that north-facing slopes are much cooler and have less evaporative demand than south-facing ones. As a result of denser vegetation attributed to relatively more available soil moisture, they are steeper than south-facing ones due to better erosion protection. Despite its young age (

The second-largest valley on Mars is Kasei Valles. This research focuses on the landforms produced by surface processes in the southern branch of Kasei Valles’s midstream. By using cross-cutting relationships, and empirical crater dating of landforms, we constructed a morpho-stratigraphical chronology of the valles. Landforms such as deeply eroded canyons, colluvial fans, landslides, topographic barriers, terraces, and trim lines are typical landforms that have been formed by surface processes.Our geomorphic mapping reveals that the valles were temporarily obstructed by two colluvial fans and a landslide, creating topographical obstacles to impound fluids (e.g lava, mudflow, water). The toe of the alluvial fans and the landslide were eroded by flights of terraces and trim lines, indicating a temporary, water-like liquid presence in the channel of the valles. The surface texture of the terrace surfaces indicates that the terrace staircases were probably created by a water-like fluid that stagnated and fluctuated for a while before the final evacuation.The chronology of these important events indicates that colluvial fans were deposited in two temporal clusters. The first colluvial fan generation was formed in the Early Amazonian period (1.74-1.14 Ga), and the second colluvial fan generation was formed in the Late-Middle Amazonian period (307 Ma). The landslide is significantly younger and is estimated to have formed 122 Ma ago. The floor of the valles’s channel is covered by platy-textured material, which was formed 90 Ma ago as lavas or mudflows, which is the youngest studied geomorphologic feature. The age of the landslide and valles’s floor help us to constrain the timing of erosional processes responsible for the flights of terraces and trimlines, which stretch along approximately 60 km from up to downstream. Accordingly, these features should be formed between 122 Ma and 90 Ma. We believe that the genesis of these features (terraces and trimlines) is associated with a Newtonian fluid (such as water) that ponded behind the colluvial fan dams and the climatic conditions that allow this fluid to stagnate over brief periods of time enough to form terraces and trimlines.

A devastating earthquake sequence occurred on February 6, 2023, within the East Anatolian fault system. Two main shocks, the Mw 7.7 Sofalaca-Şehitkamil-Gaziantep, and Mw 7.6 Ekinözü-Kahramanmaraş earthquakes occurred nine hours apart and affected 10 cities and more than an area of 100,000 km2 (PGA>0.08g). The earthquake-affected area mainly exhibits arid/semi-arid climatic conditions where approximately 15% of the landscape is characterized by steep topography (slope steepness>20°). Initial estimates of globally available predictive landslide models indicated extensive landslide distribution over the area.We examined high-resolution satellite images and aerial photos to provide a better insight into this co-seismic landslide event and its possible post-seismic consequences. These observations are going to be validated and enriched by detailed field surveys. This research presents our preliminary findings as a result of these investigations. Our observations carried out in the first two weeks after the sequence showed that rock fall and lateral spreading are the dominant landslide types, and the overall landslide population could be less than expected. Therefore, the resultant co-seismic landslide event seems unexpected, given the intensity of ground shaking and landscape characteristics. Based on the preliminary investigations, lithology, topographic relief, and climatic conditions appear to be the main variables causing these below expectations for landslide distribution. We should stress that our historical records mostly lack landslide events in arid/semi-arid conditions, as we observed in this event. In this context, this event is going to be recorded as one of a few of its kind. Our observations also showed intense ground shaking and strongly deformed numbers of hillslopes, although most have not failed yet. In particular, heavy rain and snowmelt may result in a considerable number of failures on those hillslopes that are prone to cracking and deformation due to strong ground shaking. In this respect, this area needs to be monitored for a long time to understand the earthquake legacy effect and post-seismic hillslope response.

Various mechanisms are proposed to explain landslide recovery time in the time following major earthquakes. However, research on prescribing possible recovery times following an earthquake is still relatively new. This paper provides an insight into factors governing landslide recovery time, which could be considered as a step forward in predictive modeling for landslide recovery time. To accomplish this, we examined 11 earthquake-affected areas based on the characteristics of both landslide events and landslide sites associated with diverse morphologic and climatic conditions. Our analyses indicate that the dominant characteristics of post-seismic landslide mechanisms determine the recovery time. The characteristics can be identified based on: (i) the fraction of area affected by landslides (%), (ii) mean relief and its standard deviation (m), (iii) average daily accumulated precipitation (mm) and (iv) rainfall seasonality index. If there are not enough co-seismic landslide deposits or not enough relief to trigger large deposits on hillslopes, then the recovery processes are mostly controlled by new landslides caused by a strength reduction of hillslope materials. In most of the cases, this brings a relatively quick recovery process in which the majority of post-seismic landslides may happen within a year or even in a month if sufficient intense rainfalls occur soon after the earthquake. If the predisposing factors create large co-seismic landslide deposits, then remobilization of material takes the role of the dominant mechanism and recovery may take years. Overall, our analyses show that the recovery takes relatively longer if a large amount of co-seismic landslide material is deposited within a high-relief mountainous environment where precipitation rate is low and not persistent.

– The archaeological structures buried underground are displayed by utilizing GPR. – Geomorphological units are determined via SVF and RRIM in the GIS environment. – The effects of dry farming, site-tethered pastoralism is discussed by using an ABM.

Wildfires have a long history in the Mediterranean and Atlantic coastal regions, and such devastating events are anticipated to increase in parallel with changing climatic conditions. Wildfires play an important role in short-term ecological and geomorphological changes, as they can instantly affect vegetation, soil properties, and drainage properties. In comparison to unburned conditions, wildfire alters the erosional response of hillslopes, increasing the potential for runoff and sediment flux, as reported in many studies. Specifically, wildfire-affected steep hillslopes can promote the initiation of debris flows which may cause substantial sediment delivery and increase hazard levels for society and infrastructure downstream of burned areas.In this study, we report the erosional response of hillslopes and spatial probability debris flows after the July 10, 2019, Dalaman, Göcek (Muğla) wildfire, which was effective in a total of 15 km2 forested area. We used different ground and remote sensing methods covering two years of field observation and measurements from shortly after the event. In our study, in which we compared the results obtained by conventional field-based assessments with Unmanned Aerial Vehicle (UAV) measurements, we quantified that the erosion is localized spatially in the middle and upper parts of the basins and led to an average erosion rate of more than 10 mm in two years. In addition, we revealed that the susceptibility of the debris flows after the fire has increased significantly, primarily concentrated in the far north of the fire-affected hillslope sections. We concluded that the spatial probability of debris-flow events and their runouts would increase their impacts by significantly affecting the excavation of hillslope materials, mainly boosted by salvage logging after the event. Moreover, our preliminary findings show that accurate estimates of the magnitude of post-wildfire debris flow and erosion potential are essential to comprehend immediate hazards as well as long-term geomorphic changes.This study has been produced benefiting from the 2232 International Fellowship for Outstanding Researchers Program of the Scientific and Technological Research Council of Turkey (TUBITAK) through grant 118C329. The financial support received from TUBITAK does not mean that the content of the publication is approved in a scientific sense by TUBITAK.

Landslides are one of the devastating geohazards that cause extensive socio-economic and environmental damages on local, regional, and global scales. Previous studies based on digital media sources have attracted attention to the high fatal landslide rate in Turkey, at a continental or global scale; however, the preparation of a comprehensive and long-term database for Turkey has been neglected until today. To examine this data gap, we present a new database of fatal landslide events resulting in fatalities from 1929 to 2019, which has been compiled using Turkish national and local printed and digital media reports, academic papers, disaster, and city annual reports. The fatal database of Turkey (FATALDOT) shows that, in total, 1343 people were killed in 389 fatal landslide events. The spatiotemporal distribution of the fatal landslides highlighted increasing trends with reference to two distinct hotspot zones throughout the Eastern Black Sea and Marmara Region, mostly around Istanbul megacity. Our results show that there has been a significant uniformity between the number of fatalities and fatal landslides triggered by anthropogenic and natural factors over the past decade, indicating an increasing dominance of human activities in fatality rates. Our findings also, for the first time, remarked the potential signatures of the economic crisis and political steadiness on fatal landslide trends. Nevertheless, we conclude that the increasing rate of anthropogenic disturbances in urban and mountainous areas, together with regional variances in topography and climatic setting, is essential in governing the pattern of fatal landslides.

In semi-arid ecosystems, microclimatic variations may lead to topographic asymmetry over geologic time scale due to uneven distribution of incoming solar radiation as a function of slope aspect. This phenomenon has long been recognized in geomorphology and mostly studied in catchments where may have a wide range of spatial heterogeneity in climate forcing and underlying lithology. The formation age and the size of the catchments add another level of complexity and uncertainty due to the fluctuations in prevailing climate and lithological differences in the studied catchments. However, cinder cones are natural laboratories to better understand the eco-hydro-geomorphic evolution resulted from the nonlinear interactions between vegetation, climate, and soil due to their small size, uniform lithology, well-constrained initial morphology, and relatively young age. The Sandal Divlit cinder cone located in the Kula volcanic field, western Turkey, is an inactive volcano and formed in the last stage of volcanism in the region. The climax vegetation in the primary succession following the volcanic eruption is observed on the north-facing slopes which host trees. The north-facing slopes have relatively deeper soils than south-facing slopes where host sparsely herbaceous plants and shrubs associated with thin and weakly developed soils. Airborne-LiDAR surveys and the digital elevation models having 5 m and 12.5 m spatial resolution were used to analyze the geomorphic descriptors and canopy structure of the cone as a function of aspect. The results show that north-facing slopes are steeper than south-facing ones due to better erosion protection as a result of denser vegetation. Despite its young age (This study has been produced benefiting from the 2232 International Fellowship for Outstanding Researchers Program of the Scientific and Technological Research Council of Turkey (TUBITAK) through grant 118C329. The financial support received from TUBITAK does not indicate that the content of the publication is approved in a scientific sense by TUBITAK.

The formation of badlands is commonly linked to the presence of dispersive deposits. Meanwhile, the sediments having more resistance to disintegration might also cause badlands formation given the time and adequate climate conditions. Although the notable influences of climate conditions have been highlighted on badlands morphologies so far, only a few attempts illustrated how materials weather in response to the diverse climate conditions. Supportingly, this research aims to learn about the primary weathering processes in various types of badland landforms (sharp-edged, rounded-edged, tower type, and calanchi mammellonari) in the Mediterranean arid, semi-arid, and humid climate of Turkey. For that purpose, we have used 11 badlands bedrock samples and determined climate conditions to simulate realistic weathering conditions in the laboratory condition. Bedrock samples were marl from the arid region, poorly sorted and packed sandstones from the Mediterranean region, highly consolidated sandstones from the humid region, pyroclastic sediments from the Cappadocia – semi-arid region. We have conducted four cycles representing each season during one water year to simulate precipitation and temperature variations. In this regard, we compiled the total amount and type of precipitation and insolation data for each season. Prior to the experiment, we have determined grain size, mineralogical composition, physico-chemical properties, the content of major elements of badland samples that enable us to discuss their morphological variety.Regarding the temperature conditions, we simulated day spring/autumn (~20°C), mild winter (4-5°C), winter (-2°C), summer (~25 – 35°C) conditions considering fluctuation of temperature along the different seasons. After precipitation in each cycle, represented by either rain or snow, we collected leachates to quantify the variations between the seasons by measuring volume, pH, electrical conductivity (EC), concentrations of anion, and cations.The laboratory experiments testing weathering processes under the different climate conditions and various types of badland materials show that the apparent differences in crust and desiccation crack emerged between the seasons. Although the obtained highest sediment flux in Mediterranean badlands having the deep crack systems, especially in autumn after high drying in summer, the ponds were formed relatively temporarily (a few hours) to long-lived (a few days) by filling the cracks with the sediments during spring seasons due to the scarcity in drying during the winter. The badland materials under arid climate conditions are highly likely to disintegrate because of their critical susceptibility to dispersivity; after one year of simulation (4th cycle), they became highly unstable due to their higher content of clay swelling capacity. However, the humid badland materials subjected to harsh climate conditions -snow and freezing conditions appeared to be the most durable samples reason for which is the strong cementation of coarse-grain sandstone. Seasonal trends in sample leachates' properties were also obtained. We can conclude that drying and wetting are more effective than the cooling and thawing processes in weathering of the bedrock from sampled badlands.This study has been produced benefiting from the 2232 International Fellowship for Outstanding Researchers Program of the Scientific and Technological Research Council of Turkey (TUBITAK) through grant 118C329.

Annually, a large number of landslide events that resulted in the deaths of dozens of people occur in Turkey. However, the preparation of an inventory of fatal landslide events in Turkey has been neglected until today. In this respect, a database on fatal landslide events in Turkey for the period from 1929 to 2019 was compiled from various sources comprising national and local printed and digital media reports with pre-determined keywords in Turkish, academic papers, disaster, and city annual reports, and government and aid agency reports. In the studied period, 389 landslides events that caused of death 1343 people were detected. According to the Mann-Kendall (MK) test and Sen's slope method, which is used to determine the temporal distribution characteristic of landslide events and deaths, an increasing trend is observed in both events and the number of deaths in the period comprising 1929-2019. These landslide events, which show intensity in the summer during the year, constitute two major density regions, the Eastern Black Sea Region and the Istanbul environment. In general, the Eastern Black Sea Region is represented by fatal landslides triggered by natural factors, while fatal landslides triggered by anthropogenic factors characterize the Istanbul and near vicinity. Spatially, fatal landslides were recorded in 227 different counties in 67 of 81 cities. The determination of the priority areas was evaluated by the population of the settlements exposed to the landslide and the probability value calculated with the number of landslides recorded and the relationship with the number of the dead. In conclusion, based on the final distribution pattern we revealed that the frequency of the landslides in provinces and districts where the topographic roughness is above the country average, at the Eastern Black Sea Region are strikingly high from the other hilly sections of the country.

We present the first detailed Quaternary landform map of the Büyük Menderes Graben System, located in western Turkey which is one of the most active extensional domains in the world. The main map was produced with a combination of TanDEM-X (12.5 m resolution), Red Relief Image Map, unmanned aerial vehicle, Google Earth images, and multiple fieldworks. The main map is presented at a scale of 1:160,000 although landforms were mapped at a scale of 1:15,000. The ten Quaternary landforms were defined considering their surface morphology and depositional environment. The alluvial fans, river terraces, and floodplains are the most common landforms. The spatial pattern of the alluvial fans and river terraces showed the variable rates of tectonics and surface processes along the strike of the graben system. The distribution of the meander cut-offs and paleo-shorelines imply that Büyük Menderes Graben System is vulnerable to geohazards like flash-flood sedimentation and flood events.

Badland areas are present in all continents, excluding Antarctica, and play a critical role in establishing local erosion and sedimentation rates. The presence of unconsolidated rocks (e.g., marls, sandstone, mudstone etc.) is a major driver controlling the distribution of badlands, which together with other environmental components, such as climate, tectonics, vegetation, and topography, determine their forms and processes. The mutual interaction of controlling factors in badlands areas provides a basis for developing a holistic approach to clarify their distribution patterns. Turkey's geodynamic evolution has led to the emergence of marine sedimentary rocks, pyroclastics, and continental clastics, especially in line with the uplift of the Anatolian Plateau and volcanism during the last 8 Ma.This study aims to explore the country-scale distribution of badlands and the controlling factors of this badland distribution in Turkey. Remarkably wide badlands landscapes (4494 km2) have been visually inspected using Google Earth ProTM to further digitize and extract geomorphological units by applying high-resolution multispectral images provided by WorldView-4/Maxar Technology and CNES/Airbus. To obtain exact boundaries, we eliminated contiguous flat areas surrounding the identified badlands by using red relief image map (RRIM) mosaics that express surface concavity and convexity combined with topographic slope derived from a digital elevation model of 5-m spatial resolution. Last, to determine the controlling factors of badlands distribution, we have compiled a global data set comprising 1-km resolution layers of mean annual precipitation, temperature and precipitation seasonality, aridity, NDVI, rainfall erosivity factor, elevation, and majority values of regional lithology in sub-catchments units. The enhanced investigation of the complex relationship that expresses the controlling factors of badlands distribution, has been conducted by K-means unsupervised cluster analysis.Our comprehensive regional analyses exploring the distribution and environmental attributes of major Turkish badlands identified five different groups or clusters of badlands that display spatial coherence with climatic and tectonic settings. We argue that Turkey's climatic and topographic transition zones, varying from Mediterranean climate dominated areas to the more arid Central Anatolian Plateau, and tectonically‑induced topographic barriers play a relevant role in discriminating these groups of badlands. Moreover, the Anatolian diversity of sedimentary rocks, which consists of Neogene and Paleogene continental clastics, volcano clastics & pyroclastics, and lacustrine deposits, makes an essential contribution to the identified, extensive badland distribution.This study has been produced benefiting from the 2232 International Fellowship for Outstanding Researchers Program of the Scientific and Technological Research Council of Turkey (TUBITAK) through grant 118C329. The financial support received from TUBITAK does not mean that the content of the publication is approved in a scientific sense by TUBITAK.

Along the western flank of the northern margin (Central Pontides) of the Central Anatolian Plateau, the humidity from the Black Sea is much higher than the central and eastern flanks and creates a complex relationship between surface and tectonic processes by triggering intense mass wasting activity and aggradation within narrow valleys. We identified three incised fill terrace levels and used Optically Stimulated Luminescence (OSL) dating to calculate fluvial sediment ages and cosmogenic 36Cl exposure dating to calculate limestone boulders exposure ages across the terrace surface. Stratigraphical interpretations and OSL ages of the lowest levels revealed that a fluvial fill terrace formed in the main valley at 275.6 ± 12.8 ka and was overlain by a main river-tributary junction alluvial fan that was abandoned at 39.5 ± 3.5 ka. The results collectively show the influence of climate, topography, hillslope processes, and lithology on aggradation-incision patterns of main rivers. Prolonged aggradation can prevent the channel equilibrium required to calculate rock uplift rates while also causing a new base-level and aggradation upstream. This effect can be exacerbated in uplifting mountainous regions with limited depositional areas. Bedrock incision rates based on the fluvial terrace age were between 0.15 and 0.2 mm/a since 39.5 ± 3.5 ka. However, the high aggradation within this segment of the main valley prevented incision of the channel bedrock for long periods, causing a potential underestimation of the rock uplift rate calculation. Our local period of aggradation appears to be related to increased aggradation and decreased bedrock incision rates measured 14 km upstream that were previously assumed to be the result of decreased tectonic uplift rates. This demonstrates the importance of corroborating strath terrace incision rate estimations with ages and incision rates of downstream fill terraces, if present, to check for potential interference with the tectonic signal. This work was supported by the European Commission within the Marie Curie-ITN ALErT Project [grant number FP7-PEOPLE-2013-ITN , number 607996] and the Istanbul Technical University BAP Project [grant number TDK-2017-40776 ]. We would also like to thank the CNRS-ASTER Laboratory in Aix en Provence France for AMS measurements and AcmeLabs, Canada for measurements of major and trace element concentrations. Reviews by the Geomorphology editor, Sarah Boulton (University of Plymouth), Tim Barrows (University of Wollongong), and an anonymous reviewer have greatly helped to improve the content of this work. This work was supported by the European Commission within the Marie Curie-ITN ALErT Project [grant number FP7-PEOPLE-2013-ITN, number 607996] and the Istanbul Technical University BAP Project [grant number TDK-2017-40776]. We would also like to thank the CNRS-ASTER Laboratory in Aix en Provence France for AMS measurements and AcmeLabs, Canada for measurements of major and trace element concentrations. Reviews by the Geomorphology editor, Sarah Boulton (University of Plymouth), Tim Barrows (University of Wollongong), and an anonymous reviewer have greatly helped to improve the content of this work. Publisher's Version

The extensive gypsum karst of Sivas, Turkey is one of the most outstanding examples of bare gypsum karst in the world. It displays a number of remarkable geomorphic features, including: (1) two stepped planation surfaces cut-across folded gypsum developed during an initial phase of slow base level deepening punctuated by periods of stability; (2) unusual deeply entrenched gypsum canyons related to a subsequent phase of rapid fluvial incision and water table lowering; (3) a polygonal karst of superlative quality mainly developed in the upper surface; (4) relict valleys disrupted by sinkholes in the lower erosional surface; (5) a large number of bedrock collapse sinkholes mostly associated with the lower surface; and (6) numerous cover subsidence sinkholes developed in the valley floors. This work analyses the spatial distribution, characteristics and evolution of the sinkholes within the broad Plio-Quaternary geomorphological and paleohydrological evolution of the epigene karst system dominated by autogenic recharge. A cartographic sinkhole inventory has been produced in an area covering 2820 km(2) with morphometric data and including 295 bedrock collapse sinkholes and 302 cover subsidence sinkholes. The different sinkhole types show a general spatial zonation controlled by the hydrogeological functioning of the different sectors: (1) solution sinkholes (polygonal karst) in the upper recharge area; (2) bedrock collapse sinkholes in the lower denudation surface and close to the base level, where well developed caves are inferred; and (3) cover subsidence sinkholes, with high densities probably associated with areas of preferred groundwater discharge. The morphology of the bedrock collapse sinkholes, varying from small cylindrical holes to large and deep tronco-conical depressions with gentle slopes reflect to geomorphic evolution of these sinkholes that reach exceptionally large hectometre-scale diameters. Their evolution, involving substantial enlargement and deepening, is attributed to the solutional removal as solute load of large volumes of gypsum by downward vadose flow. This type of morphological evolution with significant post-collapse solutional denudation differs from that observed in carbonate rocks characterised by lower solubility and erodibility. The analysis of historical imagery reveals that bedrock collapse sinkholes currently have a very low probability of occurrence and that buried cover subsidence sinkholes are used for urban development creating risk situations. (C) 2021 The Author(s). Published by Elsevier B.V.

The main purpose of the study is to determine the general characteristics of the landslide sizes observed in Cretaceous and Eocene aged flysch assemblages at the Western Black Sea region of Turkey by using magnitude and frequency relations. For this purpose, the magnitude and frequency relations were investigated by considering power-law scaling characteristics of the geological formations. The probability distributions were also examined by considering Double Pareto and Inverse Gamma distribution models. According to the power-law relations, the rollover effects were observed at 0.047 and 0.048 km2, and the fractal dimensions of the distributions were obtained as −1.97 and −1.41 for Cretaceous and Eocene flysch assemblages, respectively. Considering the probability distributions, the best-fits were acquired from the models Double Pareto with three parameters estimated by maximum likelihood estimation for Cretaceous flysch and Kernel density estimation for Eocene flysch. When we compared these results with the results of a study carried out in the same flysch but in another sub-catchment, it is concluded that rollover effects and fractal dimensions may not be generalized, that means, the parameters may differ site to site depending on not only spatial resolution but also morphological, climatic, and anthropogenic features of the region in concern, and conversely, landslide size distributions fit Double Pareto distribution models in general.

Roads can have a significant impact on the frequency of mass wasting events in mountainous areas. However, characterizing the extent and pervasiveness of landslides over time rarely been documented due to limitations in available data sources to consistently map such events. We monitored the evolution of a road network and assessed its effect on slope stability for a ten year window in Arhavi, Turkey. The main road construction projects run in the area are associated with a hydroelectric power plant as well as other road extension works and are clearly associated with the vast majority (90.1%) of mass movements in the area. We also notice that the overall number and size of the landslides are much larger than in the naturally-occurring comparison area. This marks a strong and negative effect of human activities on the natural course of earth surface processes. Our findings show that the damage generated by the road construction is compatible with the possible effect of a theoretical earthquake with a magnitude greater than Mw=6.0. Overall, better co- and post-construction conditions should be ensured during and after road works to mitigate the risk to local communities. We also notice a significant variation in sediment transport as a result of road construction. As a result, our study fits in the big picture of Anthropocene related changes and specifically points out at problems in mountainous areas that could undoubtedly be better managed to reduce the risk to local communities.

Landslides are one of the destructive geomorphological hazards that cause substantial socio-economic and environmental damages on a global scale. Knowing the precise number of deaths caused by landslides and their spatial and temporal distributions will facilitate a better understanding of the losses and damages, and further to prevent and minimize the damages caused by this type of disasters. Thus, reliable historical inventories, including past landslide events, are crucial in understanding the future landslide hazards and risks.Turkey, similar to mountainous countries suffering from landslides, is also high-elevated (average altitude of >1100 m) and tectonically active country located where the Europe and Asia continents meet. In the years between 1995-2014, 335 of the total 1375 fatalities caused by landslides in European countries have occurred in Turkey. This reported number not only shows that Turkey is the first country in Europe in terms of deaths caused by landslides but also implies that the landslide related problems are overwhelming than expected in Turkey. Although many studies have been carried out on individual landslides and landslide inventories in Turkey, we have limited information about the landslides that cause death. However, there are many landslide events that resulted in the deaths of tens of people every year in Turkey. Therefore, neglecting fatal landslides and their consequences resulted in an unrealistic comprehension of landslide risk. In this respect, we contribute to filling this data gap by presenting the first country-scale archive inventory of fatal landslides, their spatio-temporal distribution, and the triggering mechanism characteristics for Turkey, which is Europe's topmost deadly country.The fatal landslide events in Turkey for the period from 1929 to 2019 were compiled from various sources comprising national and local printed and digital media reports with pre-determined keywords in Turkish, academic papers, disaster, and city annual reports, and government and aid agency reports. According to the new database, 1343 people lost their lives as a result of 389 landslide events in Turkey between 1929 and 2018. In total 197 fatal landslide events, which resulted in 301 deaths, were identified due to anthropogenic triggers (i.e., construction, infrastructure, and mining activities). On the other hand, 147 landslides occurred, and 883 people lost their lives due to natural triggering factors. The natural trigger origin of the fatal landslides is concentrated in the Eastern Black Sea and is generally shallow landslides corresponding to regolithic zones where chemical weathering is severe. On the contrary, the trigger factor of 45 landslide events cannot be assigned to the FATALDOT database due to a lack of detailed information in incidence reports. The database, which is planned to be transformed into an information system with a semi-automatic update feature, is thought to be an underlying data source for future research works to prevent hazard and risk studies and landslide-related deaths in the country scale.

This multidisciplinary project investigates the implications of aridification induced by climate change and human-induced land-cover land-use change in semiarid landscapes of Turkey on erosion dynamics and landscapes patterns and morphology. Deviations from climate mean states will result in loss of vegetation productivity and soil fertility in these water-limited ecosystems and exacerbate the natural conditions in terms of natural land‑cover and soil protection for natural resources sustainability. Here, we offer a comprehensive modelling framework to explore the water-soil-vegetation interactions under climate change for the following decades.Remotely‑sensed vegetation indices and maps will be used to identify the regions where are prone to land‑cover change under climate change. Hence, the climate projections for the 21st century taken from CMIP6 model experiments will be used for anticipating the potential changes in ecosystem dynamics and boundaries in these water-limited ecosystems. Moreover, these climate projections will be used as forcing data in a vegetation-coupled landscape evolution model to understand how the landscape morphology and erosion dynamics interact with changing climate in Turkish arid lands. Besides erosion dynamics, the future of the unique geomorphic landscape feature of these regions, the Turkish badlands, will be investigated based on climate projections.The outcomes of this project will enhance the comprehension of the effects of geomorphic, hydrological, and ecological processes on natural resources under climate change in semiarid Turkish landscapes.

Various mechanisms are proposed to explain landslide recovery time in the time following major earthquakes. However, research on prescribing possible recovery times following an earthquake is still relatively new. This paper provides an insight into factors governing landslide recovery time, which could be considered as a step forward in predictive modeling for landslide recovery time. To accomplish this, we examined 11 earthquake-affected areas based on the characteristics of both landslide events and landslide sites associated with diverse morphologic and climatic conditions. Our analyses indicate that the dominant characteristics of post-seismic landslide mechanisms determine the recovery time. The characteristics can be identified based on: (i) the fraction of area affected by landslides (%), (ii) mean relief and its standard deviation (m), (iii) average daily accumulated precipitation (mm) and (iv) rainfall seasonality index. If there are not enough co-seismic landslide deposits or not enough relief to trigger large deposits on hillslopes, then the recovery processes are mostly controlled by new landslides caused by a strength reduction of hillslope materials. In most of the cases, this brings a relatively quick recovery process in which the majority of post-seismic landslides may happen within a year or even in a month if sufficient intense rainfalls occur soon after the earthquake. If the predisposing factors create large co-seismic landslide deposits, then remobilization of material takes the role of the dominant mechanism and recovery may take years. Overall, our analyses show that the recovery takes relatively longer if a large amount of co-seismic landslide material is deposited within a high-relief mountainous environment where precipitation rate is low and not persistent.

Landslides are one of the geomorphological hazards that cause significant human, economic and natural losses worldwide and in Turkey as well. In general, landslides triggered by natural factors such as earthquakes, heavy rainfall and snow melting, or human activities cause a large number of casualties. Knowing the precise number of deaths caused by landslides and their spatial and temporal distributions will facilitate a better understanding of the losses and damages, and further to prevent and minimize the damages caused by this type of disasters. In this respect, reliable historical inventories, including past landslide events, are crucial in understanding the future landslide hazards and risks. In this study a new data set of landslides that caused loss of life in the 90-year period from 1929 and 2019 has been compiled, providing new insight into the impact of landslides for Turkey, which is Europe's topmost deadly country.The new archive inventory indicates that in the 90-year period a total of 1343 people lost their lives across the region in 389 landslide events in Turkey between 1929 and 2019. The distribution of the fatal landslides is highly varied and concentrated in two distinct zones along the Eastern Black Sea Region and Istanbul mega-city. Our analysis suggests that on a country scale the mapped factors that best explain the observed distribution are topographic relief and gradient, annual precipitation and population density. Temporal trend analysis reveals a significant rise in the number of deadly landslides and hotspots across the studied period was observed. The detailed analysis showed that the control factors of landslides caused by different triggering mechanisms (i.e., natural and anthropogenic) also vary. The landslides of natural trigger origin are concentrated in areas with high topographic relief and slope values, whereas those triggered by anthropogenic factors are concentrated in areas with low topographic relief and slope values. While the slope values were 10.5° in the areas where all the fatal landslides occurred, these values were 14.5° for natural landslides and 8° for anthropogenic landslides. In the areas where landslides triggered by natural factors, the average topographic relief is approximately 600 meters higher than the landslides of anthropogenic origin. Moreover, we observed that fatal landslides have not triggered during the seasonal rainy period, but rather caused by sudden and heavy torrential rainfall during the summer period when the average annual rainfall is low. Fatal landslides triggered by natural factors are concentrated in the Eastern Black Sea section and occur on the Upper Cretaceous and Lower-Middle Eocene volcanics classified as median volcanic rocks with an average thickness of ten meters. The landslides on these lithological units are shallow landslides, which occur mainly a few meters above the regolithic zone, where chemical weathering is severe in this area. Fatal landslides of anthropogenic origin occur in urban and metropolitan centers where human activity is high due to infrastructure and construction works, and they are predominantly corresponding with areas where the topographic relief difference is low.

High Anatolian orographic margins have large variations in terms of topographic relief, precipitation, and uplift rate. These variations lead to the dynamics of mass movements and surface runoff, which are the dominant geomorphological processes in ice-free mountain landscapes. There is growing recognition that large landslides are important agents of landscape evolution, resulting in massive slope failures, which can cause extensive and rapid topographic changes in many active orogenic belts. Unlike the cognatic orogenic plateau margins in the world, there are no studies available on the large landslides and their geomorphic impact at the margins of the Anatolian Plateau. This study presents results from a regional-scale inventory of 1290 large landslides (> 1 km2) that allow the characterization of spatial distribution and landslide-dominated landscapes in the northern margins of the Anatolian Plateau. The majority of large landslides are clustered in three main zones that correspond to the Western, Central, and Eastern Pontides, which is an east-west-trending orogenic belt that represents a coalesced tectonic entity in the northern section of Turkey. Nearly 80% of large landslides have occurred in a terrain with a mean hillslope relief of > 1000 m in those three landslide-dominated landscapes. The results of regional comparisons reveal that in addition to hillslope relief and steepness, lithotectonic differences largely control the abundance of landslides along the northern margins of the Anatolian Plateau. In this respect, the spatial distribution and abundance of large landslides imply a landscape in which lithological and tectonic controls on hillslope erosion are more significant than climate. The study further shows that the parallel or perpendicular position of the landslides with respect to the direction of the drainage network is effective as positive or negative feedback in response to fluvial dissection of the plateau margins. On the other hand, there is certainly a need for more comprehensive radiometric dating studies to understand the contribution of large landslides on the erosional decay rate of Anatolian Plateau margins. Furthermore, the presence of these large landslides and the derived deposits in this dynamic terrain provide a unique opportunity for deciphering the past climatic and seismic events.

Unmanned Aerial Vehicles (UAVs), which can carry a variety of payloads, and be operated automatically or manually with ground control stations. Nowadays, UAVs can make photogrammetric flight plans and obtain photogrammetric data with existing sensor systems. Automatic data acquisition processes provide lower cost, and high spatial and temporal resolution images in a short period of time compared to other measurement methods. As a result, orthomosaics, dense point clouds and digital surface models (DSMs) are produced and these UAV-derived data are used in various disciplines such as constructions, geomatics, earth sciences, etc. In this study, the same flight plans were realized with an UAV at different altitudes and all aerial images were obtained with the same integrated digital camera. As a result of the processing of images acquired from different altitudes, orthomosaics, DSMs and point cloud were produced. In this study, it is aimed to compare the length, areal and volumetric differences of a small geostationary object. Ground control points (GCPs), which were collected by RTK-GPS (Real-Time Kinematic) in conjunction with the flight integrated into data production process in order to highly accurate product. Ultimately, cross-correlation has been done with the produced data and the terrestrial measurement. Results show that the dimension of the object depend on the flight altitude as expected, however the volumetric changes vary due to the uncertainties in the raw point cloud data.

Kelkit Çayı Vadisi heyelan yoğunluğu bakımından Türkiye ortalamasının üzerindedir. Bu vadi yamaçlarının üst kesimlerinde yapısal düzlüklerin bulunduğu alanlarda kış aylarında biriken kar ilkbahar aylarında aniden erimektedir. Eriyen kar, bu düzlüklerin önündeki eğimli yamaçlarda su çıkışlarına neden olmakta ve büyük katastrofik heyelanları tetiklemektedir. Gözlem ve literatür araştırmaları sonucunda bu tetiklenmenin kış aylarında vadideki bazı yamaçlarda karın uzun süre tutunması, ilkbaharda güneş radyasyonuna bağlı eridikten sonra sızması ve akışa geçmesiyle gerçekleştiği tespit edilmiştir. Bu etkinin yüksek olduğu yamaçlarda heyelan hassasiyetinin de yüksek olduğu bilinmektedir. Tetikleyici faktör bakımından yamaç hassasiyetini belirlemek çalışmanın amacını oluşturmaktadır. Bu amaçla çalışma alanı 3600 fiziki yamaç ünitesine bölümlenmiştir. Bu ünitelerin tutunma, sızma ve akış hassasiyetini belirlemek için, uzman görüşütarafından etken faktörler ve etki derecelerinin belirlendiği M-AHP yöntemi kullanılmıştır. Tutunma modeli için çok çözünürlüklü vadi taban düzlüğü indeksi, yükselti ve bakı, sızma modeli için solar radyasyon, Topoğrafik Nemlilik İndeksi (TNİ) ve Hidrolojik Toprak Grubu (HTG), akış modeli için ise eğim, rölyef ve HTG parametreleri kullanılmıştır. Tutunma, sızma ve akış için en yüksek kararın alındığı yamaç üniteleri belirlenerek ana tetikleyici kar erimelerinin mekânsal hassasiyet üzerinde etkisi ortaya konulmuştur. Elde edilen sonuçlarda birden fazla modelin çıktısının en yüksek (örn. tutunma-sızma-akış) değerini taşıyan yamaçlarda mekânsal hassasiyetin daha yüksek olduğu tespit edilmiştir. Bu yamaçların özellikle kuzey blokta heyelanların başlangıç bölgelerine karşılık geldiği ortaya çıkmıştır. Heyelana elverişli zemini hazırlayan “tutunma-sızma” yamaçlarının ise eski heyelan içlerine, “sızma-akış” yamaçlarının ise özellikle kuzey yamaçlar olmak üzere heyelanların transfer zonlarına karşılık geldiği tespit edilmiştir. Kuzey yamaçlarda sızmanın yüksek olmasından kaynaklı su içeriğinin fazla olması bu yamaçlarda heyelanın tektiklenmesine neden olmaktadır. Bunun dışında çalışma alanının güney bloğunda ise “tutunma-akış”ın etkin olduğu yamaçlar bulunmaktadır., Kelkit Valley has landslide density higher than the Turkey average. Accumulated snow in winter rapidly melt at the spring months and it cause water outlets on high slopes in front of these plateau and this triggers large catastrophic landslides. As a result of observation and literature investigations, it has been determined snow stay on the ground for a long term, after melt in the spring due to solar radiation it being infiltration and finally it passing flow all of which triggers landslide. It is known that landslide sensitivity is high on slopes where this effect is high. The purpose of this study is determine slope sensitivity in terms of trigger factor. For this purpose, the study area is physically divided into 3600 slope units. The M-AHP method was used to for determine the snow adhesion, infiltration, and flow sensitivity of these units, including the factors and the impact levels on this sensitivity via the expert opinion. Multi Resolution Valley Bottom Flatness, altitude and aspect parameters were used for snow adhesion. Topographic Wetness Index (TWI), Hydrologic Soil Group (HSG) and solar radiation parameters were used for the infiltration. Altitude, slope and Hydrologic Soil Group (HSG) parameters were used for the flow. The slope units that the highest decision is determine was made for adhesion, infiltration and flow were determined the spatial sensitivity based on main triggering snowmelt. In the results obtained, it was found that the spatial sensitivity is higher in the slopes having the highest value of the output of more than one model (e.g., snow adhesion-infiltration-flow). It was determined these slopes especially correspond to the starting regions of the northern block landslides. It has been found that the adhesion-infiltration slopes, which prepare convenient ground, correspond to the old-landslide, and infiltration-flow slopes correspond to the transfer zones of the landslides especially the northern block. Due to the high infiltration on the northern slopes, the water content be high and the landslide is triggered on these slopes. Apart from this, the adhesion-flow slopes effect in the southern block of the study area more.

In this study, the high-resolution palynological data derived from two cores taken from Mogan Lake in the Golbasi Basin of the Ankara region in central Anatolia (Turkey) are presented. The results provide the palaeobotanical, palaeoclimatological and palaeoenvironmental records of the last ca. 3100 years for the region which is characterised by rich natural resources and a long human occupation history. The major climatic events and the archaeological-historical periods, which are well established in previous works, along with textual sources, are related to vegetation history inferred from the palynological investigation in the study area. Five main vegetation phases are distinguished and interpreted. Our findings demonstrate that the phases of limited woody vegetation cover are chiefly coupled to several dry climate periods, with some exceptions. Steppe vegetation in an open landscape accompanied by more cultural indicators and lesser arboreal elements is inferred during the Near-East Aridification Phase at the LBA-Iron Age transition (c. 1200-850 BCE), Roman Warm Period before 700 CE, Medieval Warm Period at about 1020 CE, the 1500s and twentieth century. Only during the three dry episodes in the 1600s, 1800s and at the start of Modern Warming Period (in the twentieth century) partial arboreal recovery is deduced, and land-cover patterns are related to both natural and human-induced factors. The most extensive pine-dominated forest cover coincides mainly with the three wet climatic episodes, in Galatians times of the Hellenistic Period at c. 2080 BP, the 700s CE of the middle Byzantine era, the Seljuqs Dynasty and the earlier Ottoman Periods (c. 1165-1432/1435 CE). The former episode is represented by remarkable signs of human interference, while the others have marks of sporadically less cultivated landscape. It is concluded that a combination of various factors can be taken into account as the drivers of vegetation changes in the Ankara region, but climate appears to have been the primary agent in shaping the land-cover. (C) 2021 Elsevier Ltd. All rights reserved.

The Sinop Peninsula is located at the northernmost part of the Asia Minor (Anatolia). Its geographic position between the Central Pontide Mountains and the Black Sea together with the presence of young geological units and landforms provides favorable conditions for understanding onshore and offshore geological and geomorphic processes acting along the northern Anatolian coasts. Here, we focus on some landscapes that constitute one of the best examples along the Turkish Black Sea coast. These are inundated fluvial valleys, uplifted isthmus and marine terraces, and paleo- and active dunes.

We present a new, seismologically consistent expression for the total area and volume of populations of earthquake-triggered landslides. This model builds on a set of scaling relationships between key parameters, such as landslide spatial density, seismic ground acceleration, fault length, earthquake source depth, and seismic moment. To assess the model we have assembled and normalized a catalog of landslide inventories for 40 shallow, continental earthquakes. Low landscape steepness causes systematic overprediction of the total area and volume of landslides. When this effect is accounted for, the model predicts the total landslide volume of 63% of 40 cases to within a factor 2 of the volume estimated from observations (R2=0.76). The prediction of total landslide area is also sensitive to the landscape steepness, but less so than the total volume, and it appears to be sensitive to controls on the landslide size-frequency distribution, and possibly the shaking duration. Some outliers are likely associated with exceptionally strong rock mass in the epicentral area, while others may be related to seismic source complexities ignored by the model. However, the close match between prediction and estimate for about two thirds of cases in our database suggests that rock mass strength is similar in many cases and that our simple seismic model is often adequate, despite the variety of lithologies and tectonic settings covered. This makes our expression suitable for integration into landscape evolution models and application to the anticipation or rapid assessment of secondary hazards associated with earthquakes.

Morphological changes, caused by the erosion and deposition processes due to water discharge and sediment flux occur, in the banks along the river channels and in the estuaries. Flow rate is one of the most important factors that can change river morphology. The geometric shapes of the meanders and the river flow parameters are crucial components in the areas where erosion or deposition occurs in the meandering rivers. Extreme precipitation triggers erosion on the slopes, which causes significant morphological changes in large areas during and after the event. The flow and sediment amount observed in a river basin with extreme precipitation increases and exceeds the long-term average value. Hereby, erosion severity can be determined by performing spatial analyses on remotely sensed imagery acquired before and after an extreme precipitation event. Changes of erosion and deposition along the river channels and overspill channels can be examined by comparing multi-temporal Unmanned Aerial Vehicle (UAV) based Digital Surface Model (DSM) data. In this study, morphological changes in the Büyük Menderes River located in the western Turkey, were monitored with pre-flood (June 2018), during flood (January 2019), and post-flood (September 2019) UAV surveys, and the spatial and volumetric changes of eroded/deposited sediment were quantified. For this purpose, the DSAS (Digital Shoreline Analysis System) method and the DEM of Difference (DoD) method were used to determine the changes on the riverbank and to compare the periodic volumetric morphological changes. Hereby, Structure from Motion (SfM) photogrammetry technique was exploited to a low-cost UAV derived imagery to achieve riverbank, areal and volumetric changes following the extreme rainfall events extracted from the time series of Tropical Rainfall Measuring Mission (TRMM) satellite data. The change analyses were performed to figure out the periodic morphodynamic variations and the impact of the flood on the selected meandering structures. In conclusion, although the river water level increased by 0.4–5.9 meters with the flood occurred in January 2019, the sediment deposition areas reformed after the flood event, as the water level decreased. Two-year monitoring revealed that the sinuosity index (SI) values changed during the flood approached the pre-flood values over time. Moreover, it was observed that the amount of the deposited sediments in September 2019 approached that of June 2018.

2018 Geoinformation for Disaster Management Conference, Gi4DM 2018 -- 18 March 2018 through 21 March 2018 -- -- 135177, Groundwater depletion caused by rapid population growth, global climate change, water resources overexploitation is a major concern in many regions of the world. Consequences are not limited to a non-renewable water loss but extend to environmental degradation and geo-hazards risk increase. In areas where excessive groundwater withdrawal occurs, land subsidence induced by aquifer compaction is observed, resulting in severe socio-economic damage for the affected communities. In this work, we apply a multi-source data approach to investigate the fragile environment of Konya plain, central Turkey. The area, which is under strong anthropogenic pressures and faces with serious water-related problems, is widely affected by land subsidence. In order to analyze the spatial and temporal pattern of the subsidence process we use the Small BAseline Subset DInSAR technique to process two datasets of ENVISAT SAR images spanning the 2002-2010 period and to produce ground deformation maps and associated time-series. Results, complemented with meteorological, stratigraphic and piezometric data as well as with land-cover information, allow us to obtain a comprehensive picture of the climatic, hydrogeological and human dynamics of the study area. © Authors 2018. CC BY 4.0 License., Istanbul Üniversitesi National Research Council Consiglio Nazionale delle Ricerche Florida International University Adamawa State University, Mubi European Regional Development Fund European Space Agency: 10050, 1 National Research Council (CNR) of Italy, Institute for the Electromagnetic Sensing of the Environment (IREA), Napoli, Italy - (calo.f, pepe.a)@irea.cnr.it 2 National Research Council (CNR) of Italy, Research Institute for Geo-Hydrological Protection (IRPI), Torino, Italy - davide.notti@irpi.cnr.it 3 Department of Geodynamics, University of Granada, Granada, Spain - jpgalve@ugr.es 4 Department of Geomatics Engineering, Engineering Faculty, Bulent Ecevit University, Zonguldak, Turkey - sabdikan@beun.edu.tr 5 Geography Department, Istanbul University, Istanbul, Turkey - tolga.gorum@istanbul.edu.tr 6 Department of Earth and Environment, Florida International University, Miami, USA - oorhan@fiu.edu 7 Geomatics Engineering Department, Faculty of Engineering, Selcuk University, Konya, Turkey - bilgehanmakineci@gmail.com 8 Geomatics Engineering Department, Faculty of Engineering, Mersin University, Mersin, Turkey - myakar@mersin.edu.tr 9 Department of Geomatic Engineering, Civil Engineering Faculty, Yildiz Technical University, Istanbul, Turkey - fbalik@yildiz.edu.tr, The work was financed by the project Space Advanced Project Excellence in Research and Enterprise (SAPERE) within the Italian Program “Sviluppo e Potenziamento dei Cluster tecnologici Nazionali”. The activities were carried out through the Infrastructure of High Technology for Environmental and Climate Monitoring-PONa3_00363 project of Structural Improvement financed under the National Operational Programme for “Research and Competitiveness 2007–2013,” supported with the European Regional Development Fund and National Resources. ENVISAT ASAR data were provided by European Space Agency (ESA) in the framework of the CAT-1 ESA No. 10050 project.

As result of the Turkey’s economic growth and heavy migration processes from rural areas, Istanbul has experienced a high urbanization rate, with severe impacts on the environment in terms of natural resources pressure, land-cover changes and uncontrolled sprawl. As a consequence, the city became extremely vulnerable to natural and man-made hazards, inducing ground deformation phenomena that threaten buildings and infrastructures and often cause significant socio-economic losses. Therefore, the detection and monitoring of such deformation patterns is of primary importance for hazard and risk assessment as well as for the design and implementation of effective mitigation strategies. Aim of this work is to analyze the spatial distribution and temporal evolution of deformations affecting the Istanbul metropolitan area, by exploiting advanced Differential SAR Interferometry (DInSAR) techniques. In particular, we apply the Small BAseline Subset (SBAS) approach to a dataset of 43 TerraSAR-X images acquired, between November 2010 and June 2012, along descending orbits with an 11-day revisit time and a 3 m × 3 m spatial resolution. The SBAS processing allowed us to remotely detect and monitor subsidence patterns over all the urban area as well as to provide detailed information at the scale of the single building. Such SBAS measurements, effectively integrated with ground-based monitoring data and thematic maps, allows to explore the relationship between the detected deformation phenomena and urbanization, contributing to improve the urban planning and management.

2018 Geoinformation for Disaster Management Conference, Gi4DM 2018 -- 18 March 2018 through 21 March 2018 -- -- 135177, The Black Sea Region is one of the most landslide prone area due to the high slope gradients, heavy rainfall and highly weathered hillslope material conditions in Turkey. The landslide occurrences in this region are mainly controlled by the hydro-climatic conditions and anthropogenic activities. Rapid regional landslide inventory mapping after a major event is main difficulties encountered in this densely vegetated region. However, landslide inventories are first step and necessary for susceptibility assessment since considering the principle that the past is the key to the future thus, future landslides will be more likely to occur under similar conditions, which have led to past and present instability. In this respect, it is important to apply rapid mapping techniques to create regional landslide inventory maps of the area. This study presents the preliminary results of the semi-automated mapping of landslides from unmanned aerial vehicles (UAV) with object-based image analysis (OBIA) approach. Within the scope of the study, ultra-high resolution aerial photographs were taken with fixed wing UAV system on Aug 17, 2017 in the landslide zones which are triggered by the prolonged heavy rainfall event on August 12-13, 2016 at Bartin Kurucaşile province. 10 cm resolution orthomosaic and Digital Surface Model (DSM) data of the area were produced by processing the obtained photographs. A test area was selected from the overall research area and semi-automatic landslide detection was performed by applying object-based image analysis. OBIA has been implemented in three steps: image segmentation, image object metric calculation and classification. The accuracy of the resulting maps is assessed by comparisons with expert based landslide inventory map of the area. As a result of the comparison, 80% of the 240 landslides in the area were detected correctly, Firat University Scientific Research Projects Management Unit: 1608F607, This study was supported by Anadolu University Scientific Research Projects Commission under the grant number 1608F607. The authors would like to thank İsmail Bulut from General Directorate of Combating Desertification and Erosion for his valuable suggestions on the site-selection.

Predictive mapping of susceptibility to earthquake-triggered landslides (ETLs) commonly uses distance to fault as spatial predictor, regardless of style-of-faulting. Here, we examined the hypothesis that the spatial pattern of ETLs is influenced by style-of-faulting based on distance distribution analysis and Fry analysis. The Yingxiu–Beichuan fault (YBF) in China and a huge number of landslides that ruptured and occurred, respectively, during the 2008 Wenchuan earthquake permitted this study because the style-of-faulting along the YBF varied from its southern to northern parts (i.e. mainly thrust-slip in the southern part, oblique-slip in the central part and mainly strike-slip in the northern part). On the YBF hanging-wall, ETLs at 4.4–4.7 and 10.3–11.5 km from the YBF are likely associated with strike- and thrust-slips, respectively. On the southern and central parts of the hanging-wall, ETLs at 7.5–8 km from the YBF are likely associated with oblique-slips. These findings indicate that the spatial pattern of ETLs is influenced by style-of-faulting. Based on knowledge about the style-of-faulting and by using evidential belief functions to create a predictor map based on proximity to faults, we obtained higher landslide prediction accuracy than by using unclassified faults. When distance from unclassified parts of the YBF is used as predictor, the prediction accuracy is 80 %; when distance from parts of the YBF, classified according to style-of-faulting, is used as predictor, the prediction accuracy is 93 %. Therefore, mapping and classification of faults and proper spatial representation of fault control on occurrence of ETLs are important in predictive mapping of susceptibility to ETLs.

Earthquake‐induced landslide (EQIL) inventories are essential tools to extend our knowledge of the relationship between earthquakes and the landslides they can trigger. Regrettably, such inventories are difficult to generate and therefore scarce, and the available ones differ in terms of their quality and level of completeness. Moreover, access to existing EQIL inventories is currently difficult because there is no centralized database. To address these issues, we compiled EQIL inventories from around the globe based on an extensive literature study. The database contains information on 363 landslide‐triggering earthquakes and includes 66 digital landslide inventories. To make these data openly available, we created a repository to host the digital inventories that we have permission to redistribute through the U.S. Geological Survey ScienceBase platform. It can grow over time as more authors contribute their inventories. We analyze the distribution of EQIL events by time period and location, more specifically breaking down the distribution by continent, country, and mountain region. Additionally, we analyze frequency distributions of EQIL characteristics, such as the approximate area affected by landslides, total number of landslides, maximum distance from fault rupture zone, and distance from epicenter when the fault plane location is unknown. For the available digital EQIL inventories, we examine the underlying characteristics of landslide size, topographic slope, roughness, local relief, distance to streams, peak ground acceleration, peak ground velocity, and Modified Mercalli Intensity. Also, we present an evaluation system to help users assess the suitability of the available inventories for different types of EQIL studies and model development.

WOS: 000424358600001, This paper presents the results of a geomorphological investigation of Mount Akdag landslide complex, located on the Western Taurus range, SW Turkey. The landslide, resulting in the collapse of a 5 km segment of Mount Akdag, covers an area of 9.8 km(2) and has a volume of about 3 x 108 m(3). The 1: 15,000 scale geomorphological map (Main Map) of the Akdag landslide presented here was produced from a combination of field studies and unmanned aerial vehicle-based DSM, including aerial-photo interpretation and geomorphometric analysis of landforms. The map shows contemporary and past geomorphological hillslope processes and landforms associated with the landslide complex. Our new map suggests that the Akdag landslide was a complex rockslide consisting of multiple landslide types that developed through various movements. We found that 43 highly developed and active mass movements on the main body and side slopes of the landslide made a major contribution to the sediment input. The sediment produced in the upstream severely threatens the touristic site of Saklikent Canyon in the lower catchment via an increasing magnitude of torrents. This map will provide important data for local and national administrators regarding monitoring up-to-date mass-wasting processes, understanding the landslide and its related sedimentary dynamics, and implementing risk assessment and necessary precautions., Scientific Research Projects Coordination Unit of Istanbul University [ONAP 33594 [ID734]]; Anadolu University Scientific Research Projects Commission [1210E156], The authors would like to thank the Scientific Research Projects Coordination Unit of Istanbul University (Project number: ONAP 33594 [ID734]) and Anadolu University Scientific Research Projects Commission for their financial support through grant no. 1210E156.

In areas where groundwater overexploitation occurs, land subsidence triggered by aquifer compaction is observed, resulting in high socio-economic impacts for the affected communities. In this paper, we focus on the Konya region, one of the leading economic centers in the agricultural and industrial sectors in Turkey. We present a multi-source data approach aimed at investigating the complex and fragile environment of this area which is heavily affected by groundwater drawdown and ground subsidence. In particular, in order to analyze the spatial and temporal pattern of the subsidence process we use the Small BAseline Subset DInSAR technique to process two datasets of ENVISAT SAR images spanning the 2002-2010 period. The produced ground deformation maps and associated time-series allow us to detect a wide land subsidence extending for about 1200 km2 and measure vertical displacements reaching up to 10 cm in the observed time interval. DInSAR results, complemented with climatic, stratigraphic and piezometric data as well as with land-cover changes information, allow us to give more insights on the impact of climate changes and human activities on groundwater resources depletion and land subsidence. © 2017, by the authors; licensee MDPI, Basel, Switzerland.

In this study we develop an empirical method to estimate the volume threshold for predicting coseismic landslide dam formation using landscape parameters obtained from digital elevation models (DEMs). We hypothesize that the potential runout and volume of landslides, together with river features, determine the likelihood of the formation of a landslide dam. To develop this method, a database was created by randomly selecting 140 damming and 200 non-damming landslides from 501 landslide dams and > 60 000 landslides induced by the Mw 7.9 2008 Wenchuan earthquake in China. We used this database to parameterize empirical runout models by stepwise multivariate regression. We find that factors controlling landslide runout are landslide initiation volume, landslide type, internal relief (H) and the H/L ratio (between H and landslide horizontal distance to river, L). In order to obtain a first volume threshold for a landslide to reach a river, the runout regression equations were converted into inverse volume equations by taking the runout to be the distance to river. A second volume threshold above which a landslide is predicted to block a river was determined by the correlation between river width and landslide volume of the known damming landslides. The larger of these two thresholds was taken as the final damming threshold. This method was applied to several landslide types over a fine geographic grid of assumed initiation points in a selected catchment. The overall prediction accuracy was 97.4% and 86.0% for non-damming and damming landslides, respectively. The model was further tested by predicting the damming landslides over the whole region, with promising results. We conclude that our method is robust and reliable for the Wenchuan event. In combination with pre-event landslide susceptibility and frequency–size assessments, it can be used to predict likely damming locations of future coseismic landslides, thereby helping to plan emergency response. Copyright © 2014 John Wiley & Sons, Ltd.

The 2002 M-w 7.9 Denali Fault earthquake, Alaska, provides an unparalleled opportunity to investigate in quantitative detail the regional hillslope mass-wasting response to strong seismic shaking in glacierized terrain. We present the first detailed inventory of similar to 1580 coseismic slope failures, out of which some 20% occurred above large valley glaciers, based on mapping from multi-temporal remote sensing data. We find that the Denali earthquake produced at least one order of magnitude fewer landslides in a much narrower corridor along the fault ruptures than empirical predictions for an M 8 earthquake would suggest, despite the availability of sufficiently steep and dissected mountainous topography prone to frequent slope failure. In order to explore potential controls on the reduced extent of regional coseismic landsliding we compare our data with inventories that we compiled for two recent earthquakes in periglacial and formerly glaciated terrain, i.e. at Yushu, Tibet (M-w 6.9, 2010), and Aysen Fjord, Chile (2007 M-w 6.2). Fault movement during these events was, similarly to that of the Denali earthquake, dominated by strike-slip offsets along near-vertical faults. Our comparison returns very similar coseismic landslide patterns that are consistent with the idea that fault type, geometry, and dynamic rupture process rather than widespread glacier cover were among the first-order controls on regional hillslope erosional response in these earthquakes. We conclude that estimating the amount of coseismic hillslope sediment input to the sediment cascade from earthquake magnitude alone remains highly problematic, particularly if glacierized terrain is involved. (C) 2014 Elsevier Ltd. All rights reserved.

The Black Sea Region of Turkey is one of the most landslide prone areas due to its high slope topography, heavy rainfall, and highly weathered hillslope material conditions. Preparation of landslide inventory maps is the first step in producing landslide susceptibility maps. Ground-based methods for mapping landslide occurrences are time-consuming and expensive. Additionally, landslide mapping based on satellite imageries and aerial photographs has some limitations, including climatic conditions, cost, and limited repetitive measurement capacity. Visual interpretation-based landslide mapping, which is based on satellite imageries and aerial photographs, is a time-consuming procedure that requires an experience-based expert opinion. Therefore, the data acquisition based on unmanned aerial vehicle (UAV) and landslide event inventory maps using an object-based classification approach can be superior to other methods in terms of speed and cost. In this study, we developed a semiautomatic model using object-based image analyses for rapid mapping of shallow landslides from the data obtained from UAVs after major landslide events in the Black Sea Region of Turkey. For this purpose, two test sites—Kurucasile (Bartin) and Cayeli (Rize)—were selected. Landslide mapping models were developed in the investigation sites, and the performance of the models was evaluated. The landslides' data obtained with the developed models were compared to the landslides' data produced by the experts. The comparison process revealed that landslides mapped by using UAV data have an accuracy rate higher than 86% according to the number of landslides and 83% according to the landslide area.

A precise, accurate and complete landslide inventory is indispensable for the establishment of reliable landslide susceptibility and hazard maps. In the preparation of landslide inventories, dense vegetation cover is the major obstacle that confounds the topographic signature of landslides. Today, the growing usage of light detection and ranging (LiDAR) technology in the field of geoscience illuminates the mystery of the landscapes cloaked in dense vegetation by providing a new visual acuity to researchers. Turkey, similar to many mid-latitude mountainous countries suffering from landslides, is still continuing landslide inventory mapping with conventional methods such as aerial photo interpretations (API), although 68% of landslide events occurred under dense forest cover in the north of the country. Despite the country-wide medium-scaled landslide catalogs, the number and the abundance of landslides covered by forests remain largely unknown regardless of the increasing availability of high-resolution remote-sensing data. From these motivating insights and drawbacks, the study's focus is to evaluate the capability of mapping landslides by visually analyzing airborne LiDAR DTM derivatives and compare the results with the 1:25,000 scaled API-based inventory to understand the potential contribution of LiDAR technology in Europe's deadliest country (Turkey) in terms of landslides. The landslide mapping results for a test area located in the densely forested Ulus Basin, Western Black Sea region, reveal that the extent and the number of the mapped landslides (n = 902) from the airborne LiDAR data are much higher than those of the available API-based landslide inventory, which includes 67 landslides. Comparative analysis on topographic signatures of landslides is also underpinned on a distinct discrepancy of slope failure diagnostic indicators captured by the two available DEMs derived from LiDAR and 1:25,000 scaled topographic maps, emphasizing the success rate of LiDAR-derived DEM in recognition and mapping landslides with higher precision and accuracy. Together with all analysis results, the landslide recognizability degree assessment based on the forest cover percentage and slope height differences of landslides highlights that the LiDAR data enable landslides to be defined up to 100 m2, while this value is 20 times lower than that of estimated values from API-based landslides. In addition to underlining the contribution of LiDAR technology to the recognition of landslides hidden under dense vegetation, these findings stress the importance of LiDAR data on complete and accurate landslide inventories for production of reliable susceptibility and hazard maps and further a better understanding of the landslide processes and reducing related losses.

Kelkit Çayı, Kuzey Anadolu Fayı tarafından kontrol edilen son derece çizgisel bir vadi şekline sahiptir. Litolojik geçişlerin keskin, topoğrafik rölyef ve eğimin yüksek olduğu bir sahadır. Çalışma alanını oluşturan Kelkit Çayı’nın aşağı çığırı (Umurca-Koyulhisar arası) tektonik ve jeomorfolojik süreçlere bağlı gelişen heyelanların yoğun olduğu bir bölgedir. Çalışmanın amacı heyelan tehlikesinin yüksek olduğu bu alanda heyelanların jeolojik ve jeomorfolojik koşullara bağlı dağılım karakteristiğini ortaya koymaktır. Bu doğrultuda yüksek çözünürlüklü (SPOT, WorldView) uydu görüntülerinden oluşturulan heyelan envanterinin doğruluk kontrolleri arazi çalışmaları ile sağlanmıştır. Çalışma alanında 0.004-23.2 km2 arasında değişen 433 heyelan belirlenmiştir. Bu heyelanlar; akma, düşme, kayma tipinde olmak üzere üç ana sınıf altında haritalanmıştır. Heyelan tiplerinin eğim, rölyef, yükselti değer aralıklarında farklı dağılım gösterdikleri, litolojik olarak ise heyelanların Eosen volkanik çökel kayalarda ve Maestrihtiyen kireçtaşlarında yoğunlaştığı tespit edilmiştir. Özellikle birçoğunun kaya düşmeleri olduğu küçük heyelanların faya yakın zonlarda meydana geldiği tespit edilmiştir. Çalışmada haritalanan heyelanların belirli bir topoğrafik eğim ve rölyef değerleri arasında dağıldıkları ve jeomorfolojik açıdan geliştikleri alanların rastlantısal olmadığı, üst kesimlerde daha düze yakın plato aklanında ve paleo-heyelan topoğrafyaları içerisinde biriken karların ani erimesinin bu sürecin heyelanların tetiklenmesindeki ana neden olduğu ortaya konmuştur., Kelkit Creek is a highly linear valley controlled by North Anatolian Fault. The region has high topographical relief and slopes with sharp lithological transitions. Landslides due to tectonic and geomorphological processes are common in the downstream part of Kelkit Creek (between Umurca-Koyulhisar), which is the study area. The aim of the study is to reveal the distribution characteristics of the landslides driven by geological and geomorphological conditions in this highly landslides prone region. For this purpose, the accuracy of the landslides inventory obtained from high-resolution satellite images (SPOT, WorldView) was verified via field studies. In the study area, 433 landslides with sizes ranging 0.004-23.2 km2 and types of flow, fall and slides were mapped. It was detected that the distribution of the landslides was different for different slope, relief and elevation ranges. Also, we found out that the landslides were concentrated in Eocene aged sedimentary rocks and Maastrichtian aged limestones. Moreover, we detected that small-sized landslides (especially rock-falls) occurred in zones nearby the fault line. According to the study it was revealed that the distribution of the mapped landslides in the study area was not arbitrary and they were found to be concentrated in certain slope and relief ranges. Finally it was found that the sudden melting of the accumulated snow in the higher altitude plateau catchments and in the paleo-landslide topographies was the main triggering factor for the formation of landslides.

23 Ekim 2011 Van Depremi (Mw 7.1) ~2480 km2’lik bir alanda 70’in üzerinde heyelan tetiklemiştir. Bu heyelanları genel olarak düşme kayma ve yanal yayılma türü heyelanlar oluşturmaktadır. Heyelanların küçük bir kısmı yapıları ve ulaşım ağını doğrudan etkilemiştir. Bu heyelanlar içerisinde en ciddi ve kalıcı hasara neden olan Erçiş ilçesi, Çelebibağ Mahallesi’ndeki yanal yayılmalardır. Çalışmada yenilmelerin jeomorfolojik ve jeolojik karakteristiklerine bağlı olarak beş farklı ortamda yoğunlaştığı ortaya koyulmuştur. Bu alanlar: (1) eğim değerlerinin ortalamasının yüksek olduğu (32°) dağlık ve engebeli alanlar, (2) orta derecede eğimli (14°-18°) yıkanma yamaçları, (3) Kuvaterner alüvyonlarının egemen olduğu ve düşük yükselti farklarına sahip vadi ve ova tabanları, (4) eğim değerleri yüksek (15°- 40°) dik kıyı kuşağı ve (5) eski heyelan kütlelerinin yan yamaçlarıdır. Çalışmada heyelanların %98’inin deprem kaynak fayının tavan bloğunda oluştuğu tespit edilmiştir. Sismik faktörlerin yanı sıra topoğrafik ve litolojik koşulların heyelan oluşum ve mekansal dağılımı üzerinde birinci derecede rol oynadığı tespit edilmiştir. Dünyada gerçekleşmiş benzer faylanma mekanizması ve büyüklükteki depremlerle kıyaslandığında Van depreminin beklenenden daha az heyelan tetiklediği gözlenmiştir. Bu bakımdan heyelan sayısının ve heyelandan etkilenen alanın düşük olmasının temel nedeninin tavan bloğun (hanging-wall) ortalama eğim ve topoğrafik röliyef değerlerinin küresel eşlenik depremlere göre daha düşük olmasından kaynaklandığı sonucuna varılmıştır., October 23, 2011 Van earthquake (Mw 7.1) triggered more than 70 landslides, over an area of ~2480 km2. These landslides were mainly consisted of falls and slides, although lateral spreadings also occurred. Among these landslides, a small portion directly affected the structures and the transportation network. The most important permanent damage that was caused by these landslides was a lateral spreading which occurred in the Çelebibağ district in the Erciş County. In the study, it has been found out that the failures were geographically concentrated, which were associated with five characteristic geomorphic and geologic settings. These areas correspond to: (1) mountainous and hilly terrains with high average slope (32°), (2) modarately steep wash slopes (14°-18°), (3) plains and valley floors with low elevation differences and where Quaternary alluvials dominated, (4) the coastal belt with high steep slopes (15°- 40°), (5) flanks of the old landslides. The study revealed that 98% of the landslides were located on the hanging-wall of the earthquake source fault. It has been determined that in addition to the seismic factors, the topographical and lithological conditions played a vital role on the occurrence and spatial distribution of landslides. I observed that Van earthquake has triggered fewer landslides than expected compared to the earthquakes of similar magnitude and faulting mechanism from the world. In this respect, I conclude that the less number of landslides and the total area affected by landslides can be explained with the lower value of average hillslope gradient and topographic relief of the hanging-wall block with respect to the global equivalent earthquakes.