Processing and interpretation of JERS-1 Synthetic Aperture Radar (SAR) image of Cepu and its surrounding areas, Central Java Province, Indonesia

摘要

[ABSTRACT] Geological as well as lithological interpretations of subsurface condition from Radar image are of great interest. Conventionally, geological features are derived visually from the images. Patterns associated with geological structures/ features are recognized. Attempts to interpret lithological as well as structural geological features deeper than 1 - 10 meters are of course challenging. This research is in the early stage of an attempt to derive lithological and geological features from Radar image conducted in the Department of Geophysical Engineering of Institute of Technology Bandung, Indonesia. In this stage, we tried to derive geological structures and other features visually from JERS-1 SAR data from Cepu area in Central Java Province, Indonesia, in which a huge oil reservoir located. Conventional image processing flows applied on the data could improve data quality that lead to more interpretability of the data. Eleven anticlinal folds and one faulted anticlinal fold were detectable. These folds could be identified based on their characteristics: coarse textures and high brightness values, folded form or horizontally folded and symmetrical or repetitive patterns. Shear fault structures could also be identified based on the appearance of lineaments intersecting folds. A small difference in structure orientation interpretation from image-derived structures and the geological structure map could be resulted from the error in the process for geometric correction, especially for structures located outside ASTER image coverage acting as geometrical correction reference. Even for structures inside the ASTER image coverage, Digital Elevation Modeling (DEM) technique should be incorporated in the processing for better results in the determination of structures orientation.