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Waste dams (tailings) are used for storing the byproducts of mining operations and are very common in the mining industry. As the material they are storing can be harmful to the environment and the people in the vicinity, the construction of these dams is of high importance. During the construction phase, the topography of the site and geological–geotechnical parameters of the soils around the dam are as important as the stability and the leakage issues of the main dam body. In this paper, a nickel-ore waste dam located in Manisa-Gördes, Turkey is investigated in detail by 3-dimensional (3D) finite-element analyses. At the downstream side of the dam, there was slope instability at the right-hand side slopes due to improper loading on the top of these slopes. Whether this slope failure will affect the stability of the main dam body or not is the main question of this study. Within these confines, 3D finite-element analyses that cover a large area, including the dam, upstream and downstream sides, and the waste have been performed before and after the planned downstream slope rehabilitation. The main rehabilitation methodology employed in this study is the removal of the displaced material and re-shaping of right-hand side slopes. The results show that after the rehabilitation of the slopes, the deformations decreased considerably, and the waste dam became safer. Consequently, the study presents an interesting case study including the interaction between waste storage dam and side-slope instability with 3D finite-element analysis. At present, the planned slope excavations and the dam body construction were completed successfully. [ABSTRACT FROM AUTHOR]

The excavations of portal sections are always critical steps during the tunnel construction process, as previously excavated portal slopes can be influenced by ongoing tunnel excavations. Possible deformations that may appear in tunnels during excavations can affect the stability of portal slopes, causing the slopes to deteriorate. In addition, potential failures that may occur at portal slopes may adversely affect the tunnel support systems. Therefore, there is an obvious direct relationship between the stability of the tunnel and that of its portal slopes. In this study, the effects of portal slope failure at the entrance portal of the Geminbeli Tunnel (within the scope of the Zara-Geminbeli-Suşehri State Highway Project in Turkey) and the appropriate solution methods for this failure are explained and discussed. For the purpose of this study, the geological and geotechnical data of the failure zone are interpreted, and the necessary numerical analyses are performed to understand the performance of the proposed engineering measures. Additionally, the performances of the recommended remedial measures and redesigned support systems are discussed. [ABSTRACT FROM AUTHOR]

Landslide is a frequently observed natural phenomenon and a geohazard with destructive effects on economies, society and the environment. Production of up-to-date landslide susceptibility (LS) maps is an essential process for landslide hazard mitigation. Obtaining up-to-date and accurate data for the production of LS maps is also important and this task can be achieved by using aerial photogrammetric techniques, which can produce geospatial data with high resolution. The produced geospatial datasets can be integrated in data-driven methods for obtaining accurate LS maps. In the present study, LS map was produced by using data-driven machine learning (ML) methods, i.e. random forest (RF). An earthquake and landslide prone area from the south-eastern part of Turkey was selected as the study area. Topographical derivatives were extracted from digital surface models (DSMs) produced by using aerial photogrammetric datasets with 30 cm ground sampling distances. The lithological parameters were employed in the study together with an accurate landslide inventory, which were also delineated by using the high-resolution DSMs and orthophotos. The relationships between the landslide occurrence and the pre-defined conditioning factors were analyzed using the frequency ratio (FR) method. The results show that the RF method exhibits high prediction performance in the study area with an area under curve (AUC) value of 0.92. [ABSTRACT FROM AUTHOR]

Earthquake, depending on its intensity and location of epicentre, is one of the destructive hazards. Disaster mitigation after a severe earthquake are important to minimize its detrimental effects. Nowadays, several scientific disciplines, such as biodiversity, ecology, geosciences, natural hazards etc., utilize the Citizen Science (CitSci) approaches for various purposes, since the relevant attributes can easily be provided by non-experts with mobile devices. With the CitSci method, disaster related information can be identified and provided rapidly by locals during or after a disaster. Timely, in-situ data after an earthquake can also be collected with CitSci approaches via mobile devices, which can be even more important for all countries. In addition, scientific studies on earthquakes can be enriched and accelerated by using the information provided by volunteers. By collecting reliable data with the CitSci method, the disaster mitigation efforts can be improved, and losses may be decreased. This study aims at developing a CitSci pilot project by using the data collected by volunteers (citizens) to reduce the need for field work in creating earthquake iso-intensity maps and produce them promptly. The present study was based on the 6.8 Mw Elazig earthquake occurred at 20:55 UTC on January 24th, 2020. Through the mobile application "I felt the quake", the observations of citizens regarding the earthquake were collected. The intensities were revised from the Modified Mercalli Intensity Scale. With the help of data, an iso-intensity map was created and compared to the map produced by The Disaster and Emergency Management Presidency (AFAD), Turkey. [ABSTRACT FROM AUTHOR]

The frequency of flood events has increased in recent years most probably due to the climate change. Flood mapping is thus essential for flood modelling, hazard and risk analyses and can be performed by using the data of optical and microwave satellite sensors. Although optical imagery-based flood analysis methods have been often used for the flood assessments before, during and after the event; they have the limitation of cloud coverage. With the increasing temporal availability and spatial resolution of SAR (Synthetic Aperture Radar) satellite sensors, they became popular in data provision for flood detection. On the other hand, their processing may require high level of expertise and visual interpretation of the data is also difficult. In this study, a fusion approach for Sentinel-1 SAR and Sentinel-2 optical data for flood extent mapping was applied for the flood event occurred on August 8th, 2018, in Ordu Province of Turkey. The features obtained from Sentinel-1 and Sentinel-2 processing results were fused in random forest supervised classifier. The results show that Sentinel-2 optical data ease the training sample selection for the flooded areas. In addition, the settlement areas can be extracted from the optical data better. However, the Sentinel-2 data suffer from clouds which prevent from mapping of the full flood extent, which can be carried out with the Sentinel-1 data. Different feature combinations were evaluated and the results were assessed visually. The results are provided in this paper. [ABSTRACT FROM AUTHOR]

Landslides are among commonly observed natural hazards all over the world and can be quite destructive for infrastructure and in settlement areas. Their occurrences are often related with extreme meteorological events and seismic activities. Preparation of landslide susceptibility maps is important for disaster mitigation efforts and to increase the resilience. The factors effective on landslide susceptibility map production depend mainly on the topography, land use and the geological characteristics of the region. The up-to-date and accurate data needed for extracting the effective parameters can be obtained by using photogrammetric techniques with high spatial resolution. Data driven ensemble methods are being increasingly used for landslide susceptibility map production and accurate results can be obtained. In this study, regional landslide susceptibility map of a landslide-prone area in a part of Ordu Province in northern Turkey is produced using topographic and lithological parameters by employing the random forest method. An actual landslide inventory delineated manually by geologists using the produced orthophotos and the digital terrain model (DTM) is used for training the model. The results show that an accuracy of 83% and precision of 92% can obtained from the data and the random forest method. The approach can be applied for generation of regional susceptibility maps semi-automatically. [ABSTRACT FROM AUTHOR]

Owing to the increase in population, transportation has become one of the major research topics. Among existing transportation systems, railway is one of the most economic and fast systems, and therefore, there has been an increase in new railway constructions in recent years. In Turkey, the longest railway tunnels, the Bahce–Nurdag high-speed rail tunnels, are under construction in the southern part of the country. This twin tubes tunnels are approximately 10 km in length, and they are excavated using tunnel boring machines (TBM). The tunnel route locates in the East Anatolian Fault Zone and the portal region is composed of debris and old landslide deposits. For this reason, mitigating the potential landslide hazard is critical for the tunnel. Therefore, the present study investigates the TBM tunnelling–landslide relationship by employing 3D numerical analyses. The analyses show that the last 600 m of the tunnel has a potential landslide hazard and some additional measures should be considered along this part to ensure tunnel safety. The tunnel conditions are highly complex, and thus it is an interesting case for tunnel engineers. [ABSTRACT FROM AUTHOR]

Urban planning starts with the selection of suitable sites. The main factors and components for site selection are the geological-geotechnical parameters that directly affect the natural hazards, such as landslide and flood, construction costs and the location and distribution of existing infrastructure. The presence and accuracy of up-to-date maps in planning are very important. With the increase of high resolution Earth observation satellites, the required data can be obtained with high temporal frequency and spatial availability. From these data, the base parameters for planning can be extracted with semi- or fully-automatic methods. Among the Earth observation satellites, the Sentinel-2 mission of European Space Agency (ESA) provides high resolution optical images and the data are freely available also at different processing levels such as orthorectified images. In this study, the possibility of the landslide susceptibility map production which should be one of the base maps in urban planning by using Sentinel-2 satellite images was investigated in Mamak District of Ankara City, Turkey. The land cover and land use data were produced from Sentinel-2 images by using a supervised classification method in SNAP Tool provided by ESA. The lithological definitions were received from the General Directorate of Mineral Research and Explorations. The topographical parameters such as slope, aspect, topographic wetness index, etc. were extracted from a high resolution digital terrain model (DTM) of the area. Manually extracted landslide inventory data were employed in the logistic regression method and the produced landslide susceptibility map of the study area is presented here. [ABSTRACT FROM AUTHOR]

Turkey has been faced with an escalating energy demand and recurring droughts within the last few decades. The construction of the BAGISTAS 1 Hydroelectric Power Plant Dam, one of the dams constructed in order to solve these problems, resulted in the partial submersion of a number of pre-existing railway bridges and retaining walls of the Divrigi-Ilic-Erzincan Railway System (NE Turkey). Before the accumulation of dam water, the structural safety of these 86-year-old infrastructures, which were constructed using carbonate rocks, were investigated under saturated conditions. The maximum uniaxial compressive strength (UCS) losses under saturated conditions, after the application of freezing-thawing, and after wetting-drying cycles, were determined. For the mortar samples obtained from a drill core, the wet-to-dry UCS ratio was determined to be 0.82, suggesting a high durability performance. The natural filling material, which was used behind the retaining structures and as the railway embankment, was classified as the selective filling material, representing the best conditions for a filling material. The samples representing the retaining wall and filling materials had very high slake durability indexes, showing that they are very durable under the effect of water. The closed-form analysis for partially submerged retaining walls indicated that the structures are safe against overturning and have permissible internal wall stresses under operational conditions. In addition, the structural safety assessment of a masonry bridge was investigated using 3D Finite Element Modeling (FEM) under the designed train and expected earthquake loads, in both dry and partly immersed conditions. The results of the study showed that the strength reduction of masonry in saturated conditions, under the raised waters of the newly constructed dam, has an insignificant effect on the submerged sections and does not pose any danger to the overall structural performance. [ABSTRACT FROM AUTHOR]

Particularly in the last decade, landslide susceptibility and hazard maps have been used for urban planning and site selection of infrastructures. Most of the procedures for preparing of landslide susceptibility maps need high-quality landslide inventory map. Although the rainfall and seismic activities are accepted as triggering factor for landslides, designation of the triggering factor for each landslide in the inventory is almost impossible when well-documented records are unavailable. Therefore, during preparation of landslide susceptibility map, whole landslide records in the inventory map are used together without classifying based on the triggering factors. Although seismic activity is accepted as a triggering factor, possible effect of the use of seismic activity on production of landslide susceptibility map was investigated in this study, and the subject is open to discussion. For this purpose, a series of stability analyses based on circular failure and infinite slope model were performed considering different pseudostatic conditions. The results of analyses show that gentle slopes have higher susceptibility to failure than steeper ones, even if their stability conditions (susceptibilities) are similar for static condition. The seismic forces acting on failure surfaces may not be sufficiently taken into consideration in the conventionally prepared landslide susceptibility maps. Employing the general decreasing trend in stability condition based on slope face angle and the seismic acceleration, a new procedure was introduced for preparing of the landslide susceptibility map for a scenario earthquake. The prediction performance of occurring landslides increased after the procedure was applied to the conventionally prepared landslide susceptibility map. According to the threshold independent spatial performance analyses of the proposed methodology and the produced landslide susceptibility maps, the area under ROC curve values were calculated as 0.801, 0.933, and 0.947 for the maps prepared by considering conventional method and scenario earthquakes having M values of 5.5 and 7.5, respectively. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the slope instability problems in the Can (Canakkale — northwestern Turkey) coal mine. Slope instabilities have been one of the major problems in the pit mine since the beginning of mining activities. In particular, the West and East Sector panels in front of the TKI (Turkish Coal Enterprises) buildings and the Seramic factory located in the vicinity of the pit mine have been suffering from slope instability problems. To assess the instabilities, field data collection from boreholes, surface sampling and monitoring studies were performed. Deterministic stability analyses such as limit equilibrium, sensitivity and back analyses were applied. Based on the results, the active–passive wedge type of failure was determined as the most dominant instability type. Based on the back analysis results, mean values of residual shear strength parameters were determined as c=42kPa, Ø=8°. The results also indicate that the excessive excavation of the toe along the huge lignite open pit was the main cause of the instability. The weak contacts between the lithological units were also an important factor. Taking into consideration the results of the analyses, some remedial measures were also suggested for the coal mine such as decreasing the inclination of the toe, safe benching and effective drainage of surface water and groundwater. [Copyright &y& Elsevier]

The aim of the present study is to introduce a probabilistic approach to determine the components of the risk evaluation for rainfall-induced earthflows in medium scale. The Catakli catchment area (Cayeli, Rize, Turkey) was selected as the application site of this study. The investigations were performed in four different stages: (i) evaluation of the conditioning factors, (ii) calculation of the probability of spatial occurrence, (iii) calculation of the probability of the temporal occurrence, and (iv) evaluation of the consequent risk. For the purpose, some basic concepts such as "Risk Cube", "Risk Plane", and "Risk Vector" were defined. Additionally, in order to assign the vulnerability to the terrain units being studied in medium scale, a new more robust and more objective equation was proposed. As a result, considering the concrete type of roads in the catchment area, the economic risks were estimated as 3.6 x 106€--in case the failures occur on the terrain units including element at risk, and 12.3 x 106€--in case the risks arise from surrounding terrain units. The risk assessments performed in medium scale considering the technique proposed in the present study will supply substantial economic contributions to the mitigation planning studies in the region. [ABSTRACT FROM AUTHOR]

The main purpose of the present study is to investigate the possible application of decision tree in landslide susceptibility assessment. The study area having a surface area of 174.8 km² locates at the northern coast of the Sea of Marmara and western part of Istanbul metropolitan area. When applying data mining and extracting decision tree, geological formations, altitude, slope, plan curvature, profile curvature, heat load and stream power index parameters are taken into consideration as landslide conditioning factors. Using the predicted values, the landslide susceptibility map of the study area is produced. The AUC value of the produced landslide susceptibility map has been obtained as 89.6%. According to the results of the AUC evaluation, the produced map has exhibited a good enough performance. [ABSTRACT FROM AUTHOR]

Various natural hazards such as landslides, avalanches, floods and debris flows can result in enormous property damages and human casualties in Eastern Black Sea region of Turkey. Mountainous topographic character and high frequency of heavy rain are the main factors for landslide occurrence in Ardesen, Rize. For this reason, the main target of the present study is to evaluate the landslide hazards using a sequence of historical aerial photographs in Ardesen (Rize), Turkey, by Photogrammetry and Geographical Information System (GIS). Landslide locations in the study area were identified by interpretation of aerial photographs dated in 1973 and 2002, and by field surveys. In the study, the selected factors conditioning landslides are lithology, slope gradient, slope aspect, vegetation cover, land class, climate, rainfall and proximity to roads. These factors were considered as effective on the occurrence of landslides. The areas under landslide threat were analyzed and mapped considering the landslide conditioning factors. Some of the conditioning factors were investigated and estimated by employing visual interpretation of aerial photos and topographic data. The results showed that the slope, lithology, terrain roughness, proximity to roads, and the cover type played important roles on landslide occurrence. The results also showed that degree of landslides was affected by the number of houses constructed in the region. As a consequence, the method employed in the study provides important benefits for landslide hazard mitigation efforts, because a combination of both photogrammetric techniques and GIS is presented. [ABSTRACT FROM AUTHOR]

Mass instability in the uplifting footwall blocks of normal faults involves a range of regional and local factors including, among others, climatic setting, topography, lithology and particularly ground shaking during earthquakes. Morphological and sedimentological investigations backed by 14C dating on a huge debris flow and its zone of depreciation provided favorable insights for dynamics and causative factors of this mass wasting. Our observations showed that İsmetpaşa Debris Flow with a volume of 96 km3 involves three individual flows of decreasing significance in the late Pleistocene-Holocene period. The primary flow occurred in relation to a huge landslide developed on highly fractured and altered basaltic lavas near the crest of fault scarp c. 18.7 ka BP and probably conditioned by high precipitation rates in the early Interglacial. Although, most of the blocky debris flow transferred into the neighboring graben to form a 2 km wide debris fan, some remnant blocks and flow-induced valley-side slickensides can still be observed in the zone of depreciation. One km long secondary flow was sourced from the remnants of primary flow and was realized at 7.9 ka BP in another humid period of the Holocene. The third, though minor (less than 100 m long), mobilization of the flow occurred on one of the steep faces of secondary flow in 1960s when the mean precipitation was higher than that of today. Good coincidence of timing of individual debris flows with the humid phases of the late Pleistocene-Holocene period showed that long-term antecedent precipitation is the dominant causative factor. [ABSTRACT FROM AUTHOR]

Abstract: Seismic and multi-beam bathymetric data from the northern shelf and slope of the Cinarcik Basin, which is generated by the North Anatolian Fault Zone (NAFZ) located in the easternmost basin in the Marmara Sea, were re-interpreted to better understand the future sub-marine landslide susceptibility. Seismic data indicate that upper surface of the sub-marine extension of the Paleozoic rocks has an NNE–SSW oriented basin and a ridge type morphology controlled by the secondary faults of the NAFZ. Basins are fulfilled by Plio-Quaternary sediments, which are cut by strike-slip faults on the shelf and slope. The thickness of basin deposits reaches up to 130 m toward the linear northern slope of the Cinarcik Basin. A relatively recent sub-marine landslide, the Tuzla Landslide, cuts the slope of the Cinarcik Basin. The detailed morphological investigation indicates that the Tuzla Landslide is a deep-seated rotational landslide, which was likely triggered by activity of the NAFZ. Morphological analyses also indicate that the thick Plio-Quaternary deposits on the Paleozoic basement slid during the Tuzla Landslide event. This landslide is considered as a key event to understand the dynamics of the potential landslides on the northern shelf and slope of the Cinarcik Basin. Two areas locating on the eastern and the western sides of the Tuzla Landslide are considered as the potential areas for future sliding due to similarities of geological and geomorphological features with the Tuzla Landslide such as similar thick Plio-Quaternary deposits, similar slope morphology, and similar fault activity cutting the sediments. Considering this information, the purposes of the present study are to determine the dynamics of the possible landslide areas and to discuss their effects on the sub-marine morphology. In the light of the interpretations, the amounts of possible displaced material are obtained. Three different landslide scenarios due to possible slide surfaces for future landslides are developed and assessed. The first scenario is sliding of the sediments at the shelf break. The third scenario is a mass movement of almost whole basin deposits on the Paleozoic rocks. The latter one is evaluated as less important because of the volume of the displaced material, and the latter one is accepted as lowest possible event. Among the scenarios, the second scenario is accepted as the most critical and possible because of the amount of the slipped material and existence of faults rupture, which is considered as further sliding surfaces. These landslides will result in important changes in shelf, slope and basin floor in the study area. [Copyright &y& Elsevier]

Turkey having a long history of large earthquakes have been subjected to progressive adjacent earthquakes. Starting in 1939, the North Anatolian Fault Zone (NAFZ) produced a sequence of major earthquakes, of which the Mw 7.4 earthquake that struck western Turkey on 17 August 1999. Following the Erzincan earthquake in 1992, the soil liquefaction has been crucial important in the agenda of Turkey. Soil liquefaction was also observed widely during the Marmara and the Düzce Earthquake in 1999 (Sönmez, 2003). Aksaray city center locates in the central part of Turkey and the Tuzgolu Fault Zone passes through near the city center. The fault zone has been generated to moderate magnitude earthquakes. The geology of the Aksaray province basin contains Quaternary alluvial deposits formed by gravel, sand, silt, and clay layers in different thickness. The Tuzgolu Fault Zone (TFZ) came into being after the sedimetation of alluvial deposits. Thus, the fault is younger from lithological units and it is active. In addition, the ground water level is very shallow, within approximately 3 m from the surface. In this study, the liquefaction potential of the Aksaray province is investigated by recent procedure suggested by Sonmez and Gokceoglu (2005). For this purpose, the liquefaction susceptibility map of the Aksaray city center for liquefaction is presented. In the analysis, the input parameters such as the depth of the upper and lower boundaries of soil layer, SPT-N values, fine content, clay content and the liquid limit were used for all layers within 20m from the surface. As a result, the category of very high susceptibility liquefaction class was not observed for the earthquake scenario of Ms=5.2, 4.9% of the study area has high liquefaction susceptibility. The percentage of the moderately, low, and very low liquefied areas are 28.2%, 30.2%, and 36.3%, respectively. The rank of non-liquefied susceptibility area is less than 1%. [ABSTRACT FROM AUTHOR]

The Zonguldak province is a coastal settlement area that has been suffering from serious natural and human-induced environmental problems sourced by its geology and geomorphology. Since the province locates at the heart of a coal-producing basin, the geo-environmental problems related to mining activities such as esthetic degradation, disposal of mining wastes and subsidence of the abandoned coal galleries are badly affecting every day life in Zonguldak province. Disposal of municipal wastes is also a big problem since only one municipality out of 32 has a sanitary disposal area. The rest of the municipalities dispose their solid wastes to rivers or to the sea. The province has also some health problems, which are pointed out in the literature, related to coal mining and geologic environment. These are cytogenetic damage in peripheral lymphocytes and pheumoconiosis (most commonly seen at coal workers), goiter and cancer. Landslides are the most important hazards in the area since 13% of the total surface of the Zonguldak is affected by landslides. In this study, considering the hazard potential special attention is given to deep landslides and using the stepwise forward conditional logistic regression technique, the landslide susceptibility map for the Zonguldak province is produced. The results showed that the most important independent variables governing the landslides are slope gradient, volcanic, and sedimentary rocks of Eocene and clastic and carbonate units of Cretaceous. The landslide map is used as a base map for the production of geo-hazard reconnaissance map on which areas subjected to other important geo-hazards (flood, earthquake and subsidence) are also shown to provide guidance for both existing settlement areas to take the necessary preventive measures and for new developing settlement areas to avoid the problematic areas. [ABSTRACT FROM AUTHOR]

Debris flow is one of the most destructive mass movements. Sometimes regional debris flow susceptibility or hazard assessments can be more difficult than the other mass movements. Determination of debris accumulation zones and debris source areas, which is one of the most crucial stages in debris flow investigations, can be too difficult because of morphological restrictions. The main goal of the present study is to extract debris source areas by logistic regression analyses based on the data from the slopes of the Barla, Besparmak and Kapi Mountains in the SW part of the Taurids Mountain belt of Turkey, where formation of debris material are clearly evident and common. In this study, in order to achieve this goal, extensive field observations to identify the areal extent of debris source areas and debris material, air-photo studies to determine the debris source areas and also desk studies including Geographical Information System (GIS) applications and statistical assessments were performed. To justify the training data used in logistic regression analyses as representative, a random sampling procedure was applied. By using the results of the logistic regression analysis, the debris source area probability map of the region is produced. However, according to the field experiences of the authors, the produced map yielded over-predicted results. The main source of the over-prediction is structural relation between the bedding planes and slope aspects on the basis of the field observations, for the generation of debris, the dip of the bedding planes must be taken into consideration regarding the slope face. In order to eliminate this problem, in this study, an approach has been developed using probability distribution of the aspect values. With the application of structural adjustment, the final adjusted debris source area probability map is obtained for the study area. The field observations revealed that the actual debris source areas in the field coincide with the areas having high probability values on this final map. [ABSTRACT FROM AUTHOR]

Various statistical, mathematical and artificial intelligence techniques have been used in the areas of engineering geology, rock engineering and geomorphology for many years. However, among the techniques, artificial neural networks are relatively new approach used in engineering geology in particular. The attractiveness of ANN for the engineering geological problems comes from the information processing characteristics of the system, such as nonlinearity, high parallelism, robustness, fault and failure tolerance, learning, ability to handle imprecise and fuzzy information, and their capability to generalize. For this reason, the purposes of the present study are to perform an application of ANN to a engineering geology problem having a very large database and to introduce a new approach to accelerate convergence. For these purposes, an ANN architecture having 5 neurons in one hidden layer was constructed. During the training stages, total 40 000 training cycles were performed and the minimum RMSE values were obtained at approximately 10 000th cycle. At this cycle, the obtained minimum RMSE value is 0.22 for the second training set, while that of value is calculated as 0.064 again for the second test set. Using the trained ANN model at 10 000th cycle for the second random sampling, the debris source area susceptibility map was produced and adjusted. Finally, a potential debris source susceptibility map for the study area was produced. When considering the field observations and existing inventory map, the produced map has a high prediction capacity and it can be used when assessing debris flow hazard mitigation efforts. [ABSTRACT FROM AUTHOR]

One of the major tasks in earthquake geotechnical engineering is the preparation of liquefaction susceptibility maps. For this purpose, some indices associated with liquefaction susceptibility are used. However, the currently used indices have some limitations. In this study, a liquefaction severity index, which can be used in preparation of susceptibility maps, is suggested. The suggested severity index is applied to two sites selected from Taiwan (Yuanlin) and Turkey (Inegol) to examine performance. The application indicated that the suggested index shows a good performance for the selected sites, and can be considered as a tool for further studies. [ABSTRACT FROM AUTHOR]

Abstract: The uniaxial compressive strength (UCS) of rocks is an important intact rock parameter, and it is commonly used for various engineering applications. This parameter is mainly controlled by the mineralogical and textural characteristics of rocks. In this study, a soft computing method, an adaptive neuro-fuzzy inference system (ANFIS), was employed to estimate UCS from the mineral contents of certain granitic rocks selected from Turkey; nonlinear multiple regression analysis was then employed to validate these estimations. Five nonlinear multiple regressions and ANFIS models were constructed with three inputs: quartz, orthoclase and plagioclase. To determine the optimal model, various performance indices (R, values account for and root mean square error) were determined, and the model obtained from dataset #3 was selected as the optimal model. The coefficients of correlation for the nonlinear multiple regression and ANFIS models were 0.87 and 0.91, respectively. Thus, both models yielded acceptable results, and the ANFIS is a suitable method for estimating the UCS of rocks. [Copyright &y& Elsevier]