Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. ...Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. The presence of active faults in different directions explains the high tectonic instability and the high frequency of earthquakes. This study contributes to the effort of understanding the geothermal potential of the Northeast of Morocco. Heat source and permeability are both key factors in the geothermal process. Indeed, lineaments analysis constrains the structures and their directions and indicates severely faulted zones, which are the most promising areas for geothermal exploration. For this purpose, we used Landsat data combined with geological and structural maps available in this region. Different image processing techniques were applied including band ratio (6/2) and directional filters. To validate the results, we conducted a comparative study between linear structures, available geological data, and previous studies. Results of the automatic extraction method of lineaments from Landsat 8 OLI/TIRS indicate three main lineament systems: 1) a NE-SW system ranging from N40 to N70;2) an N-S system ranging from N10 to N45;3) an EW to WNW-ESE systems ranging from N80 to N120. Most of lineaments extracted are localized in Kebdana, Amejjaou, Nador and Melilla regions. Compared to previous studies, the NE-SW system is consistent with an extensive period (Tortonian to Pliocene);the NW-SE system is consistent with the last compressive episode (Pliocene);the N-S system is consistent with the first compressive period (Late/End Tortonian).展开更多
This paper offers a Derivation of Urban Heat Island (UHI) for Landsat-8 TIR on the application of urban climatology in Riyadh city. GIS and remote sensing are provided to determine the possibility of consolidation acr...This paper offers a Derivation of Urban Heat Island (UHI) for Landsat-8 TIR on the application of urban climatology in Riyadh city. GIS and remote sensing are provided to determine the possibility of consolidation across the heat island in Riyadh. The primary aim of this work is deviation in temperature and makes up an urban heat island (UHI). To create the database required for the study, using satellite images in monitoring thermal emission peaks for the surface of the earth (UHI), we used band ten and band eleven that represented the thermal band, which depended to extract the temperature of the surface (TOAr). The first step was Conversion DN to Radiance;the second was Radiance into degrees Kelvin and the third was Convert degrees Kelvin into degrees Celsius. In the final Produced Urban Heat Island (UHI), maps help to find out the thermal peaks clearly that affect urban climatology by elevating the temperature of the (UHI) and (UHI) peaks of the surrounding regions and the extent of its impact on the occupants of nearby countries. The paper concluded by the study area contains 10 Urban Heat Islands (UHI). Its presence has been associated with the types of land-utilization and requires intervention by the municipality of the city to hold the (UHI) and dilute the impact and types of land usage. Most impact is negative including increased energy consumption, elevated emissions of air pollutants and greenhouse gases compromised to human health and impaired water quality.展开更多
鉴于传统调制传递函数(modulation transfer function,MTF)空间域分析结果受实验目标选择影响很大,应用EROS提出的频率域线状地物法对Landsat-8卫星OLI成像仪MTF进行在轨评测,并通过对比实验验证方法。基于目标和传感器特性分析,分别建...鉴于传统调制传递函数(modulation transfer function,MTF)空间域分析结果受实验目标选择影响很大,应用EROS提出的频率域线状地物法对Landsat-8卫星OLI成像仪MTF进行在轨评测,并通过对比实验验证方法。基于目标和传感器特性分析,分别建立目标模型和系统传递函数模型,利用拟合数据求解模型参数,进而计算得到MTF值。并将EROS方法与传统T choi方法测得的MTF值进行对比。实验结果表明,EROS方法能有效应用于Landsat-8卫星OLI成像仪的MTF在轨测量,且明显减少了目标选择对于MTF评测结果的影响。展开更多
Glacial lake mapping provides the most feasible way for investigating the water resources and monitoring the flood outburst hazards in High Mountain Region.However,various types of glacial lakes with different propert...Glacial lake mapping provides the most feasible way for investigating the water resources and monitoring the flood outburst hazards in High Mountain Region.However,various types of glacial lakes with different properties bring a constraint to the rapid and accurate glacial lake mapping over a large scale.Existing spectral features to map glacial lakes are diverse but some are generally limited to the specific glaciated regions or lake types,some have unclear applicability,which hamper their application for the large areas.To this end,this study provides a solution for evaluating the most effective spectral features in glacial lake mapping using Landsat-8 imagery.The 23 frequently-used lake mapping spectral features,including single band reflectance features,Water Index features and image transformation features were selected,then the insignificant features were filtered out based on scoring calculated from two classical feature selection methods-random forest and decision tree algorithm.The result shows that the three most prominent spectral features(SF)with high scores are NDWI1,EWI,and NDWI3(renamed as SF8,SF19 and SF12 respectively).Accuracy assessment of glacial lake mapping results in five different test sites demonstrate that the selected features performed well and robustly in classifying different types of glacial lakes without any influence from the mountain shadows.SF8 and SF19 are superior for the detection of large amount of small glacial lakes,while some lake areas extracted by SF12 are incomplete.Moreover,SF8 achieved better accuracy than the other two features in terms of both Kappa Coefficient(0.8812)and Prediction(0.9025),which further indicates that SF8 has great potential for large scale glacial lake mapping in high mountainous area.展开更多
文摘Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. The presence of active faults in different directions explains the high tectonic instability and the high frequency of earthquakes. This study contributes to the effort of understanding the geothermal potential of the Northeast of Morocco. Heat source and permeability are both key factors in the geothermal process. Indeed, lineaments analysis constrains the structures and their directions and indicates severely faulted zones, which are the most promising areas for geothermal exploration. For this purpose, we used Landsat data combined with geological and structural maps available in this region. Different image processing techniques were applied including band ratio (6/2) and directional filters. To validate the results, we conducted a comparative study between linear structures, available geological data, and previous studies. Results of the automatic extraction method of lineaments from Landsat 8 OLI/TIRS indicate three main lineament systems: 1) a NE-SW system ranging from N40 to N70;2) an N-S system ranging from N10 to N45;3) an EW to WNW-ESE systems ranging from N80 to N120. Most of lineaments extracted are localized in Kebdana, Amejjaou, Nador and Melilla regions. Compared to previous studies, the NE-SW system is consistent with an extensive period (Tortonian to Pliocene);the NW-SE system is consistent with the last compressive episode (Pliocene);the N-S system is consistent with the first compressive period (Late/End Tortonian).
文摘This paper offers a Derivation of Urban Heat Island (UHI) for Landsat-8 TIR on the application of urban climatology in Riyadh city. GIS and remote sensing are provided to determine the possibility of consolidation across the heat island in Riyadh. The primary aim of this work is deviation in temperature and makes up an urban heat island (UHI). To create the database required for the study, using satellite images in monitoring thermal emission peaks for the surface of the earth (UHI), we used band ten and band eleven that represented the thermal band, which depended to extract the temperature of the surface (TOAr). The first step was Conversion DN to Radiance;the second was Radiance into degrees Kelvin and the third was Convert degrees Kelvin into degrees Celsius. In the final Produced Urban Heat Island (UHI), maps help to find out the thermal peaks clearly that affect urban climatology by elevating the temperature of the (UHI) and (UHI) peaks of the surrounding regions and the extent of its impact on the occupants of nearby countries. The paper concluded by the study area contains 10 Urban Heat Islands (UHI). Its presence has been associated with the types of land-utilization and requires intervention by the municipality of the city to hold the (UHI) and dilute the impact and types of land usage. Most impact is negative including increased energy consumption, elevated emissions of air pollutants and greenhouse gases compromised to human health and impaired water quality.
文摘鉴于传统调制传递函数(modulation transfer function,MTF)空间域分析结果受实验目标选择影响很大,应用EROS提出的频率域线状地物法对Landsat-8卫星OLI成像仪MTF进行在轨评测,并通过对比实验验证方法。基于目标和传感器特性分析,分别建立目标模型和系统传递函数模型,利用拟合数据求解模型参数,进而计算得到MTF值。并将EROS方法与传统T choi方法测得的MTF值进行对比。实验结果表明,EROS方法能有效应用于Landsat-8卫星OLI成像仪的MTF在轨测量,且明显减少了目标选择对于MTF评测结果的影响。
基金funded by the National Key R&D Program of China(Grant No.2017YFE0100800)the International Partnership Program of the Chinese Academy of Sciences(Grant No.131551KYSB20160002/131211KYSB20170046)the National Natural Science Foundation of China(41701481)。
文摘Glacial lake mapping provides the most feasible way for investigating the water resources and monitoring the flood outburst hazards in High Mountain Region.However,various types of glacial lakes with different properties bring a constraint to the rapid and accurate glacial lake mapping over a large scale.Existing spectral features to map glacial lakes are diverse but some are generally limited to the specific glaciated regions or lake types,some have unclear applicability,which hamper their application for the large areas.To this end,this study provides a solution for evaluating the most effective spectral features in glacial lake mapping using Landsat-8 imagery.The 23 frequently-used lake mapping spectral features,including single band reflectance features,Water Index features and image transformation features were selected,then the insignificant features were filtered out based on scoring calculated from two classical feature selection methods-random forest and decision tree algorithm.The result shows that the three most prominent spectral features(SF)with high scores are NDWI1,EWI,and NDWI3(renamed as SF8,SF19 and SF12 respectively).Accuracy assessment of glacial lake mapping results in five different test sites demonstrate that the selected features performed well and robustly in classifying different types of glacial lakes without any influence from the mountain shadows.SF8 and SF19 are superior for the detection of large amount of small glacial lakes,while some lake areas extracted by SF12 are incomplete.Moreover,SF8 achieved better accuracy than the other two features in terms of both Kappa Coefficient(0.8812)and Prediction(0.9025),which further indicates that SF8 has great potential for large scale glacial lake mapping in high mountainous area.
