Open AccessComparison of Different Multispectral Images to Map Hydrothermal Alteration Zones in Kokap, Kulon Progo
Author(s) -
Bayu Raharja,
Agung Setianto,
Anastasia Dewi Titisari
Publication year - 2021
Publication title -
journal of applied geology
Language(s) - English
Resource type - Journals
ISSN - 2502-2822
DOI - 10.22146/jag.60699
Subject(s) - multispectral image , advanced spaceborne thermal emission and reflection radiometer , hydrothermal circulation , multispectral pattern recognition , geology , remote sensing , geologic map , principal component analysis , mineralogy , computer science , digital elevation model , artificial intelligence , geomorphology , seismology
Using remote sensing data for hydrothermal alteration mapping beside saving time and reducing cost leads to increased accuracy. In this study, the result of multispectral remote sensing tehcniques has been compare for manifesting hydrothermal alteration in Kokap, Kulon Progo. Three multispectral images, including ASTER, Landsat 8, and Sentinel-2, were compared in order to find the highest overall accuracy using principle component analysis (PCA) and directed component analysis (DPC). Several subsets band combinations were used as PCA and DPC input to targeting the key mineral of alteration. Multispectral classification with the maximum likelihood algorithm was performed to map the alteration types based on training and testing data and followed by accuracy evaluation. Two alteration zones were succeeded to be mapped: argillic zone and propylitic zone. Results of these image classification techniques were compared with known alteration zones from previous study. DPC combination of band ratio images of 5:2 and 6:7 of Landsat 8 imagery yielded a classification accuracy of 56.4%, which was 5.05% and 10.13% higher than those of the ASTER and Sentinel-2 imagery. The used of DEM together with multispectral images was increase the accuracy of hydrothermal alteration mapping in the study area.