Remote Sensing

Using of Remote Sensing and Aeromagnetic Data for Predicting Potential Areas of Hydrothermal Mineral Deposits in the Central Eastern Desert of Egypt

Mohamed Abdelkareem — 2024-02-27

This article explored mineral resources and their relation to structural settings in the Central Eastern Desert (CED) of Egypt. Integration of remote sensing (RS) with aeromagnetic (AMG) data was conducted to generate a min_x005feral predictive map. Several image transformation and enhancement techniques were performed to Landsat Operational Land Imager (OLI) and Shuttle Radar Topography Mission (SRTM) data. Using band ratios and oriented principal component analysis (PCA) on OLI data allowed delineating hydrothermal alteration zones (HAZs) and highlighted structural discontinuity. Moreover, processing of the AMG using Standard Euler deconvolution and residual magnetic anomalies successfully revealed the subsurface structural features. Zones of hydrothermal alteration and surface/subsurface geologic structural density maps were combined through GIS technique. The results showed a mineral predictive map that ranked from very low to very high probability. Field validation allowed verifying the prepared map and revealed several mineralized sites including talc, talc-schist, gold mines and quartz veins associated with hematite. Overall, integration of RS and AMG data are powerful techniques in revealing areas of potential mineralization involved with hydrothermal processes.

Problems and Countermeasures in the geological exploration of deep mineral

Shi-dong Wang — 2024-02-27

In view of the needs of the geological exploration of the deep mineral resources, the necessity, problems and Co Untermeasures of the geological exploration of the deep mineral resources are explored.

The application of photogrammetry and remote Sensing in Engineering surveying

Xue-mei Bai — 2024-02-27

The with the development of the the global economy faster and faster, also affects the industrial science and technology To reform the innovation, and by speeding up its development speed, now modern engineering measurement Stics of wide application and fast development, the engineering measurement a more and more occupies important in The construction, strict standards for the construction of Engineering survey, can improve the quality of engineering. has made innovations in engineering measurement, added photogrammetry and remote sensing technology to improve the A Ccuracy of measurement and has been widely used. This paper firstly describes the content of photogrammetry and remote sensing, and analyzes its application in engineering Survey.

Urban Road Extraction High resolution remotely sensed imagery with Gabor texture and geometrical Features

Hualong Hu — 2024-02-27

Through the feature analysis of the frequency curve , The paper proposed a new method which integrated Gabor texture and geometrical features in the urban road Ction from high resolution remotely sensed imagery. in the experiment, the texture features in different frequencies and Different directions were obtained by a given bank of Gabor filters,andthen K-means clus Tering method is applied for imagery segmentation. The morphological methods were utilized to separate the road objects from Non-^oadobjects,and the geometrical features were applied to take out the non-road. Then the extracted roads were regulated by mathematical morphology. The result showed this proposed method could effectively extract the urban road information from high resolution Remo Tely sensed imagery.

Spectral Unmixing of Hyperspectral Images in the Presence of Small Targets

Sylvain Ravel — 2024-02-27
Generally, the content of the hyperspectral image pixel is a mixture of the reflectance spectra of the different components in the imaged scene. In this paper, we consider a linear mixing model where the pixels are linear combina_x005ftions of those reflectance spectra, called endmembers, and linear coefficients corresponding to their abundances. An important issue in hyperspectral imagery consists in unmixing those pixels to retrieve the endmembers and their corresponding abundances. We consider the unmixing issue in the presence of small targets, that is, their endmembers are only contained in few pixels of the image. We introduce a thresholding method relying on Non-negative Matrix Factorization to detect pixels containing rare endmembers. We propose two resampling methods based on bootstrap for spectral unmixing of hyperspectral images to retrieve both the dominant and rare endmembers. Our experimental results on both simulated and real world data demonstrate the efficiency of the proposed method to estimate correctly all the endmembers present in hyperspectral images, in particular the rare endmembers.

Integrating Optical and Microwave Satellite Observations for High Resolution Soil Moisture Estimate and Applications in CONUS Drought Analyses

Donglian Sun — 2024-02-27
In this study, optical and microwave satellite observations are integrated to estimate soil moisture at the same spatial resolution as the optical sensors (5km here) and applied for drought analysis in the continental United States. A new refined model is proposed to include auxiliary data like soil texture, topography, surface types, accumulated pre_x005fcipitation, in addition to Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) used in the traditional universal triangle method. It is found the new proposed soil moisture model using accumulated precipitation demonstrated close agreements with the U.S. Drought Monitor (USDM) spatial patterns. Currently, the USDM is providing a weekly map. Recently, “flash” drought concept appears. To obtain drought map on daily basis, LST is derived from microwave observations and downscaled to the same resolution as the thermal infrared LST product and used to fill the gaps due to clouds in optical LST data. With the integrated daily LST available under nearly all weather conditions, daily soil moisture can be estimated at relatively higher spatial resolution than those traditionally derived from passive microwave sensors, thus drought maps based on soil moisture anomalies can be obtained on daily basis and made the flash drought analysis and monitoring become possible.