SAR DATA APPLICATION IN GEOLOGICAL STRUCTURE IDENTIFICATION BASED ON LINEAMENTS AND SURFACE MAGNETICS AT A GEOTHERMAL FIELD

• Main Author: Kharisma Army, Edo
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/41930
• Institution: Institut Teknologi Bandung

Synthetic Aperture Radar (SAR) is a remote sensing method to produce high resolution images using microwave for detecting surface objects through dense vegetation environment. Lineaments and geological structures detection on SAR were performed visually in general. Some automatic lineaments detection method had been developed, such as Hough transform, Fuzzy C, Lineament Identification Algorithm (LIA). But there are a lot of things that need to be developed. In addition, magnetic permeability an susceptibility were used as an indicator of surface manifestation related to geological structures detection. This study is aimed to detect lineaments visually and automatically, to analyze the effectiveness of those methods, to create interpretative structure maps, to analyze the effectiveness of lineament detection visually and automatically, to determine the parameters of lineament and magnetism associated with geological structures, and to analyze lineaments and surface magnetics control on geothermal manifestation. SAR data used were PALSAR (Phased Array L-band Synthetic Aperture Radar) dual orbit and polarimetric. Yamaguchi and mSTA methods were used to detect lineaments visually and automatically. The dPSAR (dielectric of Polarimetric Synthetic Aperture Radar) method was used to identify magnetic anomalies caused by hidrothermal fluid related to geological structure. Field observation was done to validate processed data with the actual conditions in the field. The mSTA method detects 2951 lineaments, more than Yamaguchi method that detects 1170 lineaments. Interpretative structure maps produced by these methods has the same Northwest-Southeast dominant strike direction as regional structures. mSTA method had smaller offset angle (2°) than Yamaguchi method (5°) to structures in field observation (EKA-10). The mSTA was more effective and representative to detect lineaments that related to geological structures in study area. The dPSAR result indicates that lineaments associated with geological structures had a higher magnetic surface value. However, Geothermal manifestation within geological structures had low magnetic surface value due to thermal fluid activity.