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1.
Optical and microwave remote sensing data are used in conjunction with a digital elevation model to map lineaments in the central parts of the Aravalli region, Rajasthan, western India. Lineament maps interpreted from each data-set are subsequently combined to derive a composite lineament map of the area. Rose plots are used to identify the prominent trends of the lineaments and compared with published structural map of the study area. Three major trends are identified, namely, the NE–SW, NNE–SSW and EW, which are interpreted to be, related to the DF1, DF2 and DF4 deformation phases identified by the previous workers through field studies. The lineaments are classified as fold axes or faults, and a total of 10-fold axes and 30 faults mapped in the area.  相似文献   

2.
The present study was aimed to identify and delineate the groundwater potential areas in parts of Western Ghats, Kottayam, covering the upper catchment of Meenachil river. The study area is composed rocks of Archaean age and Charnockite dominated over others. The information on lithology, geomorphology, lineaments, slope and land use/land cover was generated using the Resourcesat (IRS P6 LISS III) data and Survey of India (Sol) toposheets of scale 1:50,000 (surveyed in 1969) and integrated them with raster based Geographical Information System (GIS) to identify the groundwater potential of the study area. Thus, a GIS-based model which takes account of local condition/variations has been developed specifically for mapping groundwater potential. On the basis of hydrogeomorphology, three categories of groundwater potential zones namely good, moderate and poor were identified, and delineated. The high potential zones correspond to the fracture valleys, valley fills, pediments and denudational slope, which coincide with the low slope and high lineaments density areas. The low zone mainly comprise structural hills and escarpments and these act as run-off zones. The derived panchayath-wise groundwater potentiality information could be used for effective identification of suitable locations for extraction of potable water for rural populations.  相似文献   

3.
Gondwana-derived terranes are now separated by major faults or suture zone, which are rarely simple and easily recognizable lineaments. Different association of ore mineral systems such as deposits of sediment-hosted/orogenic gold and granite-related minerals is discovered in collision and subduction zones of the Gondwana-derived terranes. They are associated with large-scale, terrane-bounding fault systems and broad areas of deformation. Mineralization mostly associated with structurally-controlled complex lodes, veins, sheeted veins and veinlets in diverse orientations. Recognizing the structural significance of lineaments and curvilinear is very difficult in tropical, arid and Antarctic regions due to environmental obstacles. Remote sensing data could be used to detect geological structures associated with suture zones between Gondwana-derived terranes especially for large inaccessible regions where fieldwork is limited or nonexistent. In this investigation, the Phased Array type L-band Synthetic Aperture Radar (PALSAR) satellite remote sensing data were used to map major geological structures in the Bentong-Raub Suture Zone of Peninsular Malaysia. It is one of the major structural zones in Sundaland, Southeast Asia, which forms the boundary between the Gondwana-derived the Sibumasu terrane and Sukhothai-Indochina arc. Structural features associated with sediment-hosted/orogenic gold deposits in the Central Gold Belt and tin mineralization in S-type granites in the Main Range were investigated using PALSAR data and comprehensive fieldwork. Results indicate that main faults strike along 340° to 350° that are intersected by many shear or lateral fault zones are high potential zone for gold mineralization in the Central Gold Belt. Hydrothermally alteration mineral zones and cataclastic rocks are also the other indicators of gold mineralized veins in the gold belt. High potential zones for tin mineralization are N–S strike-slip faults, fault zones and shear zones trending E–W, NE–SW and WNW–ESE in dissected crystalline granitic rocks that are associated with hydrothermal alteration zones in the Western Tin Belt. Lineament analysis using PALSAR satellite remote sensing data is a useful tool for mapping major geological structural features and detection of the boundary between the Gondwana-derived terranes and detailed structural analysis of fault systems and deformation with high potential for a variety of mineral resources, especially in tropical, arid and Antarctic regions.  相似文献   

4.
 以图像处理、GIS为平台,对哈萨克斯坦阿克纠宾地区的重、磁、电、遥感及地震资料进行了综合分析。指出,该地区重、磁力资料信息含量较高,对于确定盐下构造分布具有积极意义。使用遥感资料对小断层及裂隙发育状况进行研究,有助于裂隙孔隙型碳酸盐岩油藏开发注水效率的提高。同时可对扎纳若尔、阿里别克莫拉等油田的井网状况进行监控和地面设施进行调查。  相似文献   

5.
The study area is located near the town of Filippoi, north of the city of Kavala in northern Greece, known from ancient times for its rich gold mines, situated inside hydrothermal alteration zones (Fe–Mn oxide minerals). A Very High-Resolution (0.5 m pixel size) image of Worldview-2 satellite was digitally enhanced, yielding target areas of potential ore existence and lineaments. Ground-truth that followed digital image processing, revealed abandoned ancient mines, slags and ore occurrences. Also, a number of lineaments delineated on the satellite image were verified as faults.  相似文献   

6.
The present work accentuated the expediency of remote sensing and geographic information system (GIS) applications in groundwater studies, especially in the identification of groundwater potential zones in Ithikkara River Basin (IRB), Kerala, India. The information on geology, geomorphology, lineaments, slope and land use/land cover was gathered from Landsat ETM + data and Survey of India (SOI) toposheets of scale 1:50,000 in addition, GIS platform was used for the integration of various themes. The composite map generated was further classified according to the spatial variation of the groundwater potential. Four categories of groundwater potential zones namely poor, moderate, good and very good were identified and delineated. The hydrogeomorphological units like valley fills and alluvial plain and are potential zones for groundwater exploration and development and valley fills associated with lineaments is highly promising area for groundwater extraction. The spatial variation of the potential indicates that groundwater occurrence is controlled by geology, structures, slope and landforms.  相似文献   

7.
以湖南省郴州市北湖区为研究区,采用GIS技术、景观生态学原理和定量分析方法,研究了湘南丘陵区农村居民点用地总量、规模、空间形态、空间分布等景观格局变化特征,并对2004年和2009年2个时段不同海拔高度农村居民点景观格局动态变化进行了分析。结果表明:农村居民点在地形低缓处集聚;从2004年到2009年,北湖区农村居民点用地增加了168.7hm2;5年来丘陵区农村居民点平均规模增长了5.57%;在空间形态上,斑块分维数和形状指数2009年比2004年分别增加了0.031、0.189,农村居民点越来越破碎;在空间分布上,斑块间邻近距离不断缩短,平均最邻近距离缩短了13.29%,呈现出集中、连片分布的特点。  相似文献   

8.
With the advent of multispectral scanners and the availability of digital data, information extraction through remote sensing has become one of the viable tools for studying natural resources. Normally thick vegetation and soil cover are common obstacles while geologically studying an area remotely. The study area, Goa, is largely covered by settlements, private mines, and dense vegetation. This makes it difficult to decipher lithology, structures and to find their extension by ground surveying. In this paper, an attempt has been made to study a variety of image enhancement and analysis techniques to delineate geological features, lineaments, and several landuse features. The information gathered from land use features and vegetation cover is also utilized in delineating lithology and lineaments. Landsat Multi-Spectral Scanner (MSS) data both in the visual and digital form have been used for the analysis. Various photographic techniques such as Bas-relief, combined printing of positive and negative for different bands, color composites, and digital image processing techniques like ratioing, principal component analysis and ratioing of the first two principal components have been applied for geological information extraction. This paper examines comparative utility of enhancement techniques in studying geological aspects. It is found that the ratio image of PCI and PC2 gives most significant and detailed information with maximum contrast and sharp boundaries. Bas-relief images are excellent for identifying geomorphic features and lineaments.  相似文献   

9.
Generation of fire danger maps play a vital role in forest fire management like forest fire research, locating lookout towers, risk assessment and for various other simulation studies. The present study addresses remote sensing and GIS applications in generating fire danger maps for tropical deciduous forests. Fire danger variables such as fuel type, topography, temperature, and relative humidity have been used in modeling fire danger. Information on local climate patterns and past fire records has been used to derive fire frequency map of the study area. Intermediate indices were derived using multiple regressions, where fire frequency data is taken as dependent variable. Results indicate that forests near human settlements are more vulnerable to forest fires.  相似文献   

10.
汶川地震灾后农田和森林植被恢复遥感监测   总被引:1,自引:1,他引:1  
赵旦  张淼  于名召  曾源  吴炳方 《遥感学报》2014,18(4):958-970
2008年汶川8.0级特大地震对当地的生态系统造成了极大的破坏,为了评估5年来灾区农田和森林植被的恢复情况,利用逐年机载高分辨率遥感影像,结合星载遥感数据和地面调查数据,开展了灾区农林植被恢复状况监测。在农田恢复监测方面,结合2008年地震发生后以及2013年5月中旬的机载高分辨率遥感数据,采用目视解译的方式对汶川地震中受损农田的恢复状况进行监测与评估,同时利用GVG(GPS、Video和GIS)农情采样系统的作物种植成数调查结果,分析了灾后作物种植结构的变化。结果表明,灾区1592 ha受损农田,5年后仅有约17.5%得到了恢复和耕种使用。就耕地利用强度而言,重灾区耕地利用率较高,作物种植结构没有发生重大变化。在森林恢复状况监测方面,对典型区(岷江干旱河谷区和盆周山地区的3个重点区域)采用目视解译方式识别出森林变化,并结合大区域尺度规一化植被指数(NDVI)时间序列变化分析,对整个灾区的森林损毁和恢复情况做出评价。监测结果显示,汶川县、什邡市和绵竹市的森林植被恢复情况总体较好,但是一些坡度较大的损毁区、次生灾害频发区的森林尚未恢复,大区域尺度的统计结果显示,地震重灾区的46381 ha重度损毁森林植被和177025 ha中度损毁森林植被区域,完全恢复的区域占13.52%和25.84%,部分恢复的区域都占到50%。在自然恢复较为困难的区域,如汶川县中部和东北部、都江堰市北部、彭州市北部、什邡市北部、绵竹市北部、安县北部及北川县南部等,需要加强人工干预。遥感监测方法既适用于震后的农田和森林恢复状况动态监测,也适用于其他自然灾害发生时对灾区农田和森林植被破坏状况进行应急监测,具有实际应用价值和良好的发展前景。  相似文献   

11.
对郫县安德镇、新胜镇、都江堰市崇义镇2006年和2016年的遥感图像进行解译,分析该区域居民聚落的时空演变情况,动态描述了该区域内农村居民点的延伸和消亡过程,并综合运用GIS的缓冲区分析、叠置分析等手段对社会经济影响下的聚落变迁特征进行探讨。  相似文献   

12.
In recent years satellite remote sensing techniques have greatly aided identification of fractures/joints/faults in connection with groundwater exploration. However, due to some constraints in filtering out the type of fracture i.e. shear fracture, tensional fracture, mineralised fracture etc. as to their “open or closed” nature from groundwater aspects, there is need of adding geophysical survey, particularly resistivity survey to further enhance the accuracy, and hence minimise drilling failures. The area under study is a part of Ranchi plateau and lithologically comprising of granite-gneiss. The present paper lays stress on an integrated approach for localising well sites through satellite data analysis and resistivity profiling along with vertical electrical sounding which is based on fracture patterns. With this combined effort i.e. firstly considering the surfacial features like drainage, geomorpho-logy, lithology and lineaments, and secondly taking into account geophysical survey aspects, i.e. depth and thickness of fracture zone, lateral extent, different layer parameter, etc., fairly accurate results are achieved. In the presnt study this type of an integrated survey has been carried out in Lohardaga and Gumla districts in Bihar, the results of which are highlighted in the paper.  相似文献   

13.
The general tendency of mapping groundwater resource using remote sensing and Geographic Information System (GIS) techniques involve assigning higher weightage to geomorphology. But this cannot be used as a thumb rule everywhere, especially an area where many ductile and brittle zones are prevalent. The influence of texture and structure of sheared rocks might play a control over retaining and permitting groundwater to flow. Attur valley is characterized by the presence of many shear zones and faults and hence the rocks are highly fissile within the shear zones. The present study tries to establish a new ranking and weightage scheme and hence a new spatial model for groundwater resource mapping in shear zone area like Attur Valley. This spatial model can be verified with field data such as water level data, pump test and resistivity data.  相似文献   

14.
This research is aimed at developing a model for assessing land use compatibility in densely built-up urban areas. In this process, a new model was developed through the combination of a suite of existing methods and tools: geographical information system, Delphi methods and spatial decision support tools: namely multi-criteria evaluation analysis, analytical hierarchy process and ordered weighted average method. The developed model has the potential to calculate land use compatibility in both horizontal and vertical directions. Furthermore, the compatibility between the use of each floor in a building and its neighboring land uses can be evaluated. The method was tested in a built-up urban area located in Tehran, the capital city of Iran. The results show that the model is robust in clarifying different levels of physical compatibility between neighboring land uses. This paper describes the various steps and processes of developing the proposed land use compatibility evaluation model (CEM).  相似文献   

15.
ABSTRACT

The cartographic identification and characterization of urban settlements is problematic, particularly in varied areas or in large geographical extensions. This is due to the divergence between morphological area structures and data attribution, which is generally available at the level of administrative units. Most existing experiences focus on small regions or use indirect data, from which only indirect information can be derived. This paper proposes an identification of urban settlements in the European Union space, which combines urban population and shape through geographic information system (GIS) techniques. For that purpose, 1 km2 cells with associated population data are used. A procedure is developed establishing three different types of urban settlements, according to population and population density values: high-density urban clusters, small and medium-sized towns, and very small towns. A validation of this procedure is performed using direct survey from local experts in 10 selected study areas. The final results show that 78,307 urban settlements can be identified: 88.17% of them are classified as “very small towns,” 10.75% as “small and medium-sized towns,” and 1.08% as high-density urban clusters. This exercise generates new information for the European Union and surrounding countries, and yields the basis for further research. All GIS operations are performed using vector layers, which is not usual in large-area regional studies.  相似文献   

16.
The aim of this study is to derive environmental factors that are likely to influence malarial distribution from Nigeriasat-1 in a geographical information systems (GIS) environment and relate it to the empirical evidence of reported malarial cases in the hospitals using discriminant analysis (DA) to characterize, identify and map malarial risk zones. It is found that using a stepwise DA, Nigeriasat-1 and GIS it is possible to classify the accurately the low malarial risk zone (100%), medium and high risk zones (83.33%), with an overall accuracy of 88.9% being achieved for the study area. The results obtained were in agreement with the ground validation exercise that was carried out and the cross validation method of ‘‘leaving-one-out’ in DA function. These findings indicate that Nigeriasat-1 and GIS combined with statistical technique of DA can be utilized as a decision support tool for a precise identification of the areas warranting mitigation efforts.  相似文献   

17.
Geospatial modelling for goral habitat evaluation   总被引:1,自引:0,他引:1  
This study attempts to evaluate the habitat suitability of Chilla Sanctuary of Rajaji National Park for goral(Nemorhaedus goral) spread over 25859 sq km area. The IRS-1B false colour imagery, Survey of India topographical maps and ground observations were used to generate the spatial information on the extent of forest cover, waterholes, slope, settlements and the road network in and around the Sanctuary. The geospatial modelling was attempted using Arc/Info geographic information system (GIS). While proximity to waterholes, open forests with intermittent grasslands and steep slopes (30 degree or more) were considered as favourable conditions, the proximity to roads/settlements and flat terrain was taken as unfavourable condition. The results of this study showed that about 14 per cent area of the Sanctuary is highly to moderately suitable for goral. An additional 5 per cent area becomes available to goralif gujjars (tribals living inside sanctuary) are settled outside the sanctuary. Besides highlighting the endangered condition of the habitat for goral, this study demonstrates potential of remote sensing and GIS techniques for wildlife habitat suitability evaluation.  相似文献   

18.
基于高分辨率遥感影像的汶川地震道路损毁评估   总被引:6,自引:0,他引:6  
强烈地震造成道路基础设施的损毁,严重影响应急救灾工作.因此,及时准确地对灾区道路损毁情况进行评估,具有十分重要的现实意义.以汶川特大地震道路损毁评估工作为例,介绍了利用高分辨率卫星遥感影像进行地震灾害道路损毁评估的技术方法.通过对灾区20个县(市、区)国/省道基础设施损毁情况评估,结果表明,汶川、北川等6个县道路重度损毁,3个县(市)中度损毁,11个县(区)轻度损毁.表明该方法能够在应急期间缺乏地面调查的情况下,充分利用高分辨率遥感图像,对道路震害损毁进行快速及较为准确的评估.  相似文献   

19.
在汶川-芦山两次强震作用下,先天脆弱与高风险并存的山区县成为受灾最为严重的地理单元。针对灾区地理信息离散度高、可变参数多、收集难度大等现状,选取雅安芦山"4·20"地震重灾区宝兴县为实证研究区,应用3S技术,基于信息数据库逻辑设计原理,构建了震后统一投影坐标系统的地理信息数据库。在此基础上,结合实例介绍了数据库的应用:叠加分析、专题图可视化。灾区宝兴县震后地理信息的数字化和集成化,通过数据库支撑下的GIS空间分析功能和可视化表达,可为灾区重建规划选址和灾害风险评价提供数据支撑。  相似文献   

20.
One of the main geological evidence for many ore-bearing deposits and mineralized regions is the existence of points in highly fractured zones and the fragmentation intensity resulted from development of hydrothermal alteration along the fractures, the process leading to the occurrence of ore deposits. In this paper, a new algorithm has been proposed including a set of image processing techniques for detection the lineaments in satellite images by means of programming in MATLAB environment. The set of utilized methods includes line segment extraction by EDLine algorithm, merging line segments by Tavares method and linking the resulting line segments based on the collinearity and proximity criterion. The tectonic structures were stabilized by B-Spline curve fitting. The proposed algorithms were implemented on the ASTER image of a structurally multiple fractured region located in the central Iran, and the lineament map of Venarch area has been depicted. The results obtained from the proposed algorithms indicate a high accuracy of the operations detection of 80% for the reference map lineaments and the overall accuracy of the method is effectively reported as 62%. Combination of the above algorithms proposes a new method that precisely resulted in obtaining image processing of geological evidence for increasing the accuracy and decreasing the risk, before any field operations.  相似文献   

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