Jurnal Geografi
Vol 15, No 1 (2023): JURNAL GEOGRAFI

Identification of Fault Zone in Bali Using GGMPlus Gravity and Alos-2 Palsar-2 Data

I Putu Dedy Pratama (Indonesian Agency for Meteorological, Climatological, and Geophysical Agency (BMKG) Masters Program in Environmental Science, Udayana University)
Takahiro Osawa (Yamaguchi University International Collaboarion Office (YUICO), Udayana University Center for Research and Application of Satellite Remote Sensing (YUCARS) Yamaguchi University, Japan)
Abd Rahman As-Syakur (Center for Remote Sensing and Ocean Sciences (CReSOS) Udayana University Center for Environmental Research (PPLH), Udayana University)



Article Info

Publish Date
11 Feb 2023

Abstract

The local active fault in Bali has a small magnitude (M<5) but has destructive potential because it is very close to residential areas. Mapping the fault area on Bali is needed to identify the parameters of faults. This study used gravity data from GGMplus, topographic data from DEMNAS, and lineaments using ALOS-2 PALSAR-2 data. Validation and interpretation using the geological map of Bali and seismicity data. We interpret the subsurface using the gravity derivative method to identify the type of fault movement. Identify fault locations using lineament extraction from SAR data processed by directional filters. The composite image red-green-blue (RGB) for HH, HV, and VV polarization was used for automatic lineament extraction and then corrected manually. The results of the gravity method succeeded in identifying 29 of the 30 faults from the geological map of the Bali sheet and a new spot from PALSAR-2. Bali land has 12 thrust faults, 11 strike-slip faults and six normal faults. The image of PALSAR-2 (L band) has succeeded in making a fault lineament map for the Bali region. The lineament extraction results from PALSAR-2 obtained four new faults (Pesanggaran, Sepang, Tegal Badeng, and Banyuwedang), while four faults were not identified (Tampaksiring Fault, Plaga, Mambal, and Munduk-Rajasa). NE-SW dominates the strike directions, and the dip angles are 45-80 degrees. We propose 30 faults in Bali, including 26 defects from geological maps with changes in length and location shift and four new marks extracted from automatic lineament.Keywords: Remote Sensing, Earthquake, Derivative Gravity, Lineament, SARĀ 

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Journal Info

Abbrev

geo

Publisher

Subject

Earth & Planetary Sciences Education Environmental Science Social Sciences Other

Description

Jurnal Geografi is published as a scientific communication media in the field of Geography Education in particular and Geography in general, as well as other related fields, for faculty members, alumni of Geography Education both from the Faculty of Social Sciences of State University of Medan and ...