Liquefaction potential of Quaternary alluvium in Bolu settlement area,Turkey

Groundwater bearing alluvial units in the seismically active settlement areas may bring out probable damage on the urban and built environment due to liquefaction. Bolu settlement area and surroundings are located in the North Anatolian Fault Zone. Geotechnical boreholes were drilled in order to determine the distribution of the geological units, to obtain representative soil samples and to measure groundwater level. Quaternary aged alluvium is the main geological unit in the South of study area. Stiffness and consistency of the soils were determined by Standart penetration test. P and S wave velocities of soil have been measured along the seismic profiles. The index and physical properties of the samples have also been tested in the laboratory. Liquefaction potential and safety factor of the sandy levels in Quaternary aged alluvium were investigated by different methods based on SPT and V _s. Liquefaction seems to be a significant risk in case of an earthquake with a _max = 0.48 g and M _w = 7.5 at different levels of the boreholes. This situation may bring out environmental problems in the future.     

Assessment of geo-environmental properties depressing urban development with GIS: a case study of Kozlu settlement,Turkey

Kozlu is a mining town only 5 km away from the main city of Zonguldak and initially was not favored for settlement due to its rugged and hilly topography. However, along with hard coal production in large quantities throughout the years came the industrialization at its full speed with plenty job opportunities which then gave rise to intense population in the region where there were only a few sheds and slums just a century ago. Workers migrating to Kozlu in thousands needed dwellings to live in, but the law, so-called the Coal Basin Restrictions Law which came in effect in 1910, hindered the implementation of zoning plans. Planned housing was not possible in the region not until the abolishment of the law in 1986. During these 76 years, the settlement in the area mostly by the mining and industry workers was carried out without proper zoning plans, usually on demand basis. Today because of this unplanned housing and harsh topography, the Kozlu settlement area (KSA) has a history of being attraction point for many natural and man-made disasters which can be summarized as are topography, geological and carstic structure, mining activities and mass movements. In this study, a settlement suitability map is produced for the study area using a geographic information system. The map produced is designated into four settlement suitability zones, namely suitable to settlement, slightly suitable to settlement, suitable to settlement with precautions and unsuitable to settlement. It clearly shows that 24.73% of the study area lies in suitable and slightly suitable to settlement areas while the bulky rest pertains to suitable to settlement with precautions and unsuitable to settlement. The latest studies show that the 37.5% of the buildings and houses in the KSA are situated on the lithologic units identified as hydrogeological permeable and semipermeable, 7.8% on carstic caverns and a hefty rate of 47.6% on the surfaces deformed by mining-induced subsidence. Therefore, it is needless to claim that the administrators of Kozlu should promptly develop a settlement plan for the welfare of the city.     

A GIS model for preliminary hazard assessment of swelling clays,a case study in Harran plain (SE Turkey)

Swelling behavior of clayey soils regarded as a hidden disaster, causes a great deal of damage in light hydraulic structures such as drinking water network, irrigation pipes or open canal linings through which water can easily leak and penetrate into soil during loading and unloading stages. Early identification during site investigation and laboratory testing is extremely important to ensure that the appropriate design strategy is adopted. The clay soils having swelling potential are generally found in arid and semi-arid regions, such as in the Şanlıurfa-Harran plain located in the southeast of Turkey. The problems associated with swelling clays occurred for the lightweight hydraulic structures constructed in Turkey have been met during the construction of irrigation structures in the scope of Southeast Anatolian Project as the Turkey’s greatest water resources project. Therefore, the identification of such soils and the assessment of their swelling potential parameters are necessary for hazard mitigation planning and land-use management. In this scope, extensive geotechnical study is executed for an investigation area. The samples were obtained from the Harran plain where many irrigation canal structures are constructed, and geotechnical study was performed on these samples. Atterberg limit tests often provide the basic field information to substantiate the soil’s swelling nature. The plasticity index (PI) and liquid limit (LL) values are also used extensively for classifying swelling soil and should always be determined during preliminary investigations. Because of this, LL and PI are assessed by using geographical information system (GIS)-based computer software, and LL and PI contour maps are created. Swelling percentages of the soil samples were carried out on both undisturbed and compacted soil samples by using direct methods. As a result of this extensive study, the values of swelling percentages determined for each location are used to obtain the swelling potential hazard map of the area by means of a GIS program. The results of GIS analyses for this area indicate that the analyses based on a lot of data introduce meaningful results for this study. It is expected that these maps will be a useful tool for planners and engineers in their efforts to achieve better land-use planning and to decide necessary remedial measures.     

An integration of GIS and remote sensing in groundwater investigations: A case study in Burdur, Turkey

The importance of groundwater is growing based on an increasing need and decreasing spring discharges in the Burdur area. Remote Sensing and the Geographic Information System (GIS) have been used for investigation of springs, which are an important groundwater source. The chemical composition of groundwater is not of drinking water quality in Burdur city and water in the Burdur residential area is being obtained from the Cine plain.The purpose of this study was to investigate new water sources by using remote sensing and GIS methods. Geology, lineament and land use maps of the research area were prepared using the Landsat TM satellite image composed of different analyses on the TM 7–4-1 band. In addition, contours, creeks, roads and springs were digitized using a topographic map of 1/100,000 scale to produce a drainage density map. A groundwater potential map was produced which integrated thematic maps, such as annual rainfall, geology, lineament density, land use, topography, slope and drainage density. According to this investigation, the surrounding villages of Askeriye, Bugduz, Gelincik, Taskap and Kayaalt were determined to be important from the point of view of groundwater potential in the research area.     

基于GIS城镇土地利用防灾适宜性评价方法分析

城镇土地利用规划及城市建设应重视土地的防灾适宜性评价,由于地质灾害对人类的生命和财产造成了严重的危害,所以要从防灾的角度进行城镇土地利用适宜性评价。开发基于GIS城镇建设用地防灾适宜性评价方法,借助IDRISI软件,通过对比分析GIS-OWA与布尔决策和权重线性叠加（WLC）等多准则评价方法在决策策略上的区别,计算了唐山市地质灾害影响下的土地利用适宜度     

Integrative approach of RS and GIS in characterization of land suitability for agriculture: a case study of Darna catchment

Land elements like slope, soil depth, land use/land cover, water holding capacity, soil texture, soil erosion, elevation, potential of hydrogen, etc. determine the suitability for agriculture. Land suitability analysis is a one of the methods of assessment of detecting inherent capacities, potential and suitability levels of the lands for agriculture, and was utilized with the same land elements in this study. A multi-criterion decision making approach using IRS P6 LISS-IV satellite dataset within a GIS environment was used to identify suitable areas for agriculture in the Darna catchment. Experts’ opinions, literature review, and correlation technique were used to decide influencing criteria, assign scores to sub-criteria, and judgment formation in pairwise comparison matrix. All thematic layers of criteria were integrated with each other in GIS using the weighted overlay technique and generated agriculture suitability map into four classes according to FAO. About 23% of the area is under agriculture in the study region. This area can extend up to 69% under agriculture converting fallow land, scrub land, and sparse forest according to soil qualities with suitability levels, i.e., highly suitable (19%), moderately suitable (16%), and marginally suitable (34%). About 31% (19,219 ha) of reviewed area are classified in the class permanently “not suitable” for agriculture. Moderately and marginally suitable land requires the irrigation facility for efficient agriculture. This study emphasizes that about 46% area has potential as agriculture land and it will help improve the financial condition of the farmers.     

Estimation of soil erosion using RUSLE in a GIS framework: a case study in the Buyukcekmece Lake watershed,northwest Turkey

This study was aimed at predicting soil erosion risk in the Buyukcekmece Lake watershed located in the western part of Istanbul, Turkey, by using Revised Universal Soil Loss Equation (RUSLE) model in a GIS framework. The factors used in RUSLE were computed by using different data obtained or produced from meteorological station, soil surveys, topographic maps, and satellite images. The RUSLE factors were represented by raster layers in a GIS environment and then multiplied together to estimate the soil erosion rate in the study area using spatial analyst tool of ArcGIS 9.3. In the study, soil loss rate below 1 t/ha/year was defined as low erosion, while those >10 t/ha/year were defined as severe erosion. The values between low and severe erosion were further classified as slight, moderate, and high erosion areas. The study provided a reliable prediction of soil erosion rates and delineation of erosion-prone areas within the watershed. As the study revealed, soil erosion risk is low in more than half of the study area (54%) with soil loss <1 t/ha/year. Around one-fifth of the study area (19%) has slight erosion risk with values between 1 and 3 t/ha/year. Only 11% of the study area was found to be under high erosion risk with soil loss between 5 and 10 t/ha/year. The severe erosion risk is seen only in 5% of the study area with soil loss more than 10 t/ha/year. As the study revealed, nearly half of the Buyukcekmece Lake watershed requires implementation of effective soil conservation measures to reduce soil erosion risk.     

采空区建筑地基适宜性及沉降变形计算工程实例分析

基于稳定采空区场地并结合某一工程实例进行建筑地基沉降变形计算分析,并对采空区地基适宜性进行综合评判。提出一种适合于采空区地基的荷载影响深度 确定方法,采用概率积分法对采空区场地不同区域剩余变形进行预测,提出考虑活化变形、剩余变形、附加变形的采空区建筑地基沉降变形计算方法,研究结果表明：（1）建筑荷载相同时判别系数越小（0.10 （自重应力）、0.08 、0.07 、0.05 ）,荷载影响深度越大;判别系数相同时建筑荷载越大,荷载影响深度也随之非线性增大。（2）对于一般采空区地基,宜采用 （附加应力）= 0.10 判别标准确定荷载影响深度;对于复杂采空区地基,宜采用 0.05 判别标准确定荷载影响深度。（3）在常规方法上（ 0.20 ）确定的荷载影响深度 ,对于采空区地基经对比分析,1.4 和1.8 荷载影响深度可作为一般采空区地基和复杂采空区地基工程设计参考。（4）在不引起活化变形的最高层数建筑荷载下,地表剩余变形量非常小可忽略不计,采空区建筑地基沉降变形主要是土层附加压缩变形。（5）数值模拟结果表明,采空区内边缘沉降较大、不均匀沉降明显,不宜作为建设场地;采空区中央沉降较小,没有明显不均匀沉降,宜作为建设场地。     

Typhoon disaster in China: prediction,prevention, and mitigation

Typhoon-induced disaster is one of the most important factors influencing the economic development and more than 250 million in China. In view of the existing state of typhoon disaster prediction, prevention, and mitigation, this paper proposes a new probability model, Multivariate Compound Extreme Value Distribution (MCEVD), to predict typhoon-induced extreme disaster events. This model establishes prevention criteria for coastal areas, offshore structures, and estuarine cities, and provides an appropriate mitigation scheme for disaster risk management and decision-making.     

Spatial analysis of morphometric indices: the case of Bolu pull-apart basin,western section of North Anatolian Fault System,Turkey

Advances in quality, acquisition and processing of high-resolution digital topography over the past decade have enabled geomorphologists to interpret topography in terms of tectonic processes in a quantitative and more objective way. This study defines the tectonic impact of the North Anatolian fault system (NAFS) on the evaluation and activity of the Bolu pull-apart basin using morphometric indices based on topographic maps. In this study, three different indices including valley floor width to height ratio (Vf), asymmetry factor (Af), and Stream Length Gradient Index (SL) are applied to the tectonic basin area. To detect the deviation from spatial randomness of applied indices, the weighted correlation coefficient Moran’s I is used, and results are interpreted at 99% confidence interval. According to the results, the tectonic impact of NAFS on the northern and western sides of the basin distinctly differs from one another. Clustered distribution of Vf and Af values on the southern side of the basin margin reveals that this side of the basin margin is tectonically more deformed compared with the northern side. The applied methodology reveals that the spatial analysis of the morphometric indices proved to be the effective tool in analyzing tectonic influence of the fault system on the opposite side of the basin margins.     

Resource allocation for regional earthquake risk mitigation: a case study of Tehran,Iran

This paper presents a new optimization model to help cities in seismically active developing countries decide (1) How much to spend on pre-earthquake mitigation versus waiting until after an event and paying for reconstruction or simply not rebuilding damaged buildings? (2) Which buildings to mitigate and how? and (3) Which buildings to reconstruct and how? It extends previously developed optimization models to consider the particular issues that arise in such countries. First, the model allows for the possibility that some damaged buildings will not be reconstructed immediately and keeps track of any lost building inventory. Second, buildings can be mitigated to, or when damaged, reconstructed to, any appropriate structural type and seismic design level. Finally, the model objectives include minimizing the chance of an extremely high death toll in any one earthquake and minimizing the average annual death toll across earthquakes. The model is illustrated through a case study analysis for Tehran, Iran.     

A generic decision model for developing concentrated rural settlement in post-disaster reconstruction: a China study

The increasing impacts of natural disasters on disadvantaged rural areas, especially in developing countries, have led to concerns regarding post-disaster rural settlement reconstruction. Various approaches, including resettlement and in-situ reconstruction, have been adopted, both of which disregard changing the pattern of dispersed settlement in villages. Against a pattern of dispersed settlement, developing a concentrated rural settlement (CRS) within a village is argued to enable the resilience of rural villages and provide a basis for sustainable development after a disaster. Nevertheless, this has received little attention when determining a plan of actions for post-disaster reconstruction. No specific guidelines can be referenced when developing CRS in post-disaster reconstruction due to the lack of a generic decision model. Therefore, this study examines the process of developing CRS in post-disaster reconstruction by mapping four cases selected in Dujiangyan, China, after the 5.12 Sichuan Earthquake in 2008. The examination leads to establishing a generic decision model for developing CRS in post-disaster reconstruction, which incorporates all the proficiencies embodied in the existing practices. This model provides an alternative tool for planning CRS in post-disaster reconstruction. It can also serve as a vehicle for identifying both effective practices and weak areas by comparing varying cases.     

基于RS和GIS的地质灾害易发性定量评价:以湖北省五峰县为例

根据地质灾害的群发性和区域性的特点,运用地质统计学理论,通过分析,选取研究区内致灾因子,采用信息量模型进行地质灾害易发性定量评价。文中采用地质统计学信息量法,以GIS技术和RS技术为基础,从致灾机理上对各致灾因子进行选取和分析,使用GIS空间分析技术,完成了地质灾害易发性分区定量分析。分析结果表明,研究区内:(1)软硬相间碳酸盐岩类、(2)与河谷距离50～350m的斜坡带、(3)软硬相间碎屑岩类、(4)公路两侧1km范围、(5)斜坡在断裂带影响范围以内(1km)、(6)与河谷距离<50m或350～550m等6大影响因子对地质灾害的发生起主导作用。其中,除"公路两侧1km范围"为人类工程活动外,其他因素均为地质动力作用。研究完成的五峰县地质灾害易发分区定量评价,为五峰县的经济发展和城镇规划提供了科学依据,同时为以后在鄂西南地区进行地质灾害遥感解译提供了参考。     

Flood prediction and mitigation in coastal tourism areas,a case study: Hurghada,Egypt

Flood mitigation involves the management and control of floodwater movement, such as redirecting flood runoff through the use of floodwalls and flood gates, rather than trying to prevent floods altogether. The prevention and mitigation of flooding can be studied on three levels: on individual properties, small communities, and whole towns or cities. The current study area is located in Hurghada on the Red Sea, which is considered an important area for coastal tourism. The study area is located at distance 7.50 km from El Gouna city along the Red Sea and east of Hurghada–Al Ismaileya road. The aim of this research is to derive the runoff flow paths across the study area and their flow magnitudes under different rainfall events of 10, 25, 50, and 100 year return periods in order to design the flood mitigation measures to protect such important areas. Field data (e.g., topographic data and rainfall intensities) were collected for the study area. The results indicated that the site is exposed to high flash flood risk and protection work is required. In order to protect the area from flood risks, locations of number of drainage channels and dams were selected and designed based on flood quantity and direction. The proposed mitigation system is capable of protecting this crucial area from flood risks and increases the national income from tourism. This study can be applied in different areas of Egypt and the world.     

Seismic risk assessment of buildings in urban areas: a case study for Denizli,Turkey

This study aims to carry out a seismic risk assessment for a typical mid-size city based on building inventory from a field study. Contributions were made to existing loss estimation methods for buildings. In particular, a procedure was introduced to estimate the seismic quality of buildings using a scoring scheme for the effective parameters in seismic behavior. Denizli, a typical mid-size city in Turkey, was used as a case study. The building inventory was conducted by trained observers in a selected region of Denizli that had the potential to be damaged from expected future earthquakes according to geological and geotechnical studies. Parameters that are known to have some effect on the seismic performance of the buildings during past earthquakes were collected during the inventory studies. The inventory includes data of about 3,466 buildings on 4,226 parcels. The evaluation of inventory data provided information about the distribution of building stock according to structural system, construction year, and vertical and plan irregularities. The inventory data and the proposed procedure were used to assess the building damage, and to determine casualty and shelter needs during the M6.3 and 7.0 scenario earthquakes, representing the most probable and maximum earthquakes in Denizli, respectively. The damage assessment and loss studies showed that significant casualties and economic losses can be expected in future earthquakes. Seismic risk assessment of reinforced concrete buildings also revealed the priorities among building groups. The vulnerability in decreasing order is: (1) buildings with 6 or more stories, (2) pre-1975 constructed buildings, and (3) buildings with 3–5 stories. The future studies for evaluating and reducing seismic risk for buildings should follow this priority order. All data of inventory, damage, and loss estimates were assembled in a Geographical Information System (GIS) database.     

Site selection for hazardous wastes: A case study from the GAP area, Turkey

The increase in the popularity of using environmental design criteria in town and country planning has brought about the need to fully identify the principles to determine the best location of hazardous wastes to be landfilled. This environmental management issue has received considerable attention because of its applications in urban and rural infrastructure planning, industrial development planning as well as health, housing, transportation and agricultural schemes. This paper explains a method to determine how to locate suitable sites for hazardous waste landfilling area by using the site screening study. It demonstrates how the criteria such as geology, topography, land use, climate, earthquake and other related factors can be introduced into the overlayer technique to determine the suitable site selection in a region. The research was undertaken in the Southeastern Anatolia Project (known as GAP in Turkey) region where identifying the land resources is crucial for agricultural and water management purposes. The paper also explains the validity of the method employed on the site selection process for hazardous wastes. The introduced method may enable more accurate design procedure for planning in environmental management in future.     

京津冀地区城市人居环境气候舒适性评价

京津冀地区城市聚集,目前在京津冀协同发展规划下,随着都市圈产业结构调整,各城市面临大量人口流动迁移,人居环境气候舒适性将影响人口重布。以京津冀地区13个主要城市作为研究对象,根据1951-2013年的气候资料,采用温湿指数THI和风效指数K,综合评价各城市气候舒适度,并加以对比分析。结果表明：近63 a来,本区13个城市人居气候环境舒适性较高;区内各城市气候舒适性分布特点表现为由东北向西南,舒适性呈现降低趋势,河北省内秦皇岛、唐山、廊坊、邯郸等多个城市气候舒适性均高于北京天津两大城市。以全年气候舒适程度由高到低排序：秦皇岛>唐山>廊坊、邯郸、北京 > 承德 > 张家口 > 石家庄、邢台、保定、衡水 > 沧州、天津。这将成为引导人口分流的有利因素,驱动人口高度密集区进行有序合理疏散,缓解北京天津的大城市病问题。     

High‐resolution remote sensing and GIS techniques for geobase data supporting archaeological surveys: A case study of ancient Doliche,southeast Turkey

The detection, surveying, and analysis of ancient settlement structures using remote sensing techniques offer a unique opportunity to quickly map the locations of archaeological objects in a relatively short time. High‐resolution images contribute information to the documentation and spatial relation of these objects, especially if Geographic Information Systems (GIS) and Web‐based applications are used. The aim of this study was to assess the potential use of satellite data and aerial imagesacquired by a remote‐controlled balloon to generate geospatial data with a range of resolutions and information depths. The study area was Doliche, in the landscape of ancient Commagene (Turkey), where conventional flight campaigns are impossible or strongly restricted. Recently generated data sets (i.e., topographic maps, ortho‐images, terrain models) were combined with field observations to derive ancient and modern landscape patterns and their possible relation to an assumed “ancient procession road” between the village Doliche (Dülük) and the nearby sanctuary of theRoman divinity Iupiter Dolichenus. © 2010 Wiley Periodicals, Inc.