Merged SAR and Optical
The map package files (merged.mpk) were prepared and can be opened by Arc Gis 10.8.2 and above versions. The map package data files include the SAR data (RISAT-1 from ISRO-Bhoonidhi) in HH,HV- polarizations, DEM ( USGS ) and IRS LISS III (Bhuvan-NRSC) data with the 30m spatial resolution were downloaded from the respective websites. Geology data in 1:50,000 scale is downloaded from GSI Bhukosh. The resolution merged data of Optical and SAR data has been prepared using Brovey transform in ERDAS 2015 software. The output file have advantages of both optical and microwave features. Extracted the Lineaments(.shp) from the coupled data of merged SAR and improved and verified with the DEM, Optical, SAR and Geology data sets. All these data generation and Statistical calculation done with the help of ArcGIS software. ArcGIS guide will help to create shape files, Attribute table calculations of length, classification. Azumutal trend calculations of each lineaments done using Split lines and other geometric calculations giving the trend of each lineament and finally export the map (All .jpg files). Rose diagrams was prepared based on the trend of lineaments with the help of Rockworks 17 software. The generated Azimuthal trend data in lineament shape file can be import to linears - utilites - Rose diagram. I was prepared Rose diagram of different class of lineaments using frequency calculation method. Lineaments are the linear geological features can extend from few meters to hundreds of kms. Geologically lineaments are either structural or stratigraphical, typically it will comprise fault, fold axis, bedding contacts, dyke intrusions, shear zone or a straight coast line. Mapping lineaments using remote sensing is economical, faster can act as a preliminary study. Generally lineaments have been mapped using the optical remote sensing data such as Landsat, Resourcesat etc. For India, Lineaments were mapped using the LISS III and LISS IV of Resourcesat-1 & 2 at a scale of 1:50k. However in tropical region like India, limited exposure of ground due to vegetation cover, lineaments may go unnoticed in optical remote sensing data. This problem can be overcome by Synthetic Aperture Radar (SAR) data, which can penetrate ground significantly. With the launch of RISAT-1satelite, data availability of SAR data is immense for Indian region. Aim of this study to explore the SAR data and merged SAR and optical data for lineament mapping.
Steps to reproduce
1. Download the RISAT 1 satellite data from the Bhoonidhi - ISRO, LISS III data from NRSC Bhuwan, DEM data from NRSC Bhuwan or USGS website. Geology (1:50k) or Regional geology data can be download from GSI- Bhukosh website. 2. Use Arc GIS 8.0 and above software and its tools to study the data. 3. Resolution merge of SAR and optical data were done using Brovey transform in ERDAS 2015 software. 4. Keep the display of 10% and keep background values (R,G,B) as zero for better visualization. 5. Extract Lineaments using ArcGIS tools and compare with other data sets of Optical, DEM, HH and HV polarizations with the help of ArcGIS software. 6. Lineament shape file attribute table will help to calculate all statistics. Split line and other geometry calculation in ArcGIS will give the trend of the each lineaments. 7. Rose diagram has been prepared from the Azimuthal trend of each lineaments with the help of Rockwork17 software. Import the data in linears tool in utilities of Rockworks17 software. 8. All the data and software are open access and freely available. High resolution data and higher version softwares are paid based and give better results.