Image Processing Techniques Applied to Satellite Data for Extracting Lineaments Using PCI Geomatica and Their Morphotectonic Interpretation in the Parts of Northwestern Himalayan Frontal Thrust

摘要

Lineament extraction technique is a very considerate method for the study of regional structural geology and tectonics. Lineaments are geomorphological features associated with fractures at a scale ranging from meters to tens of kilometer. In this work, an attempt of automatic extraction of lineaments and their morphotectonic interpretation has been made by satellite image processing in the NW part of HFT. Lineaments are auto-extracted from Landsat-8 OLI using PCI Geomatica software to achieve this objective edge enhancement, and filtering techniques were used. The methodology of this work enumerates the following steps: (1) pansharpening, (2) principal component analysis, (3) directional filtering, (4) lineament extraction, (5) density map generation, and (6) trend analysis. Extracted lineaments were draped over Cartosat DEM-derived ancillary products to understand the morphotectonic condition of the area. The orientation analysis of the extracted lineaments indicates that the major trend of linear features in the study area is NW-SE and parallel to the major structural trend (NNW-SSE). The trend of lineaments is in concordance with the direction of major faults, fractures, and associated geomorphological features. The lineament density value is relatively higher in the high relief area owing to the presence of fractured rocks to the structurally active terrain along the Siwalik range. The overlapping of lineament over geological map, slope aspect map, and drainage map confirms that some of the lineaments identified in the area are morphological features associated with fractures and faults. The study reveals that analysis of extracted lineament with the geological map and DEM gives a good interpretation of active morphotectonics in the parts of northwestern HFT.