PENDEFINISIAN PROSPEK NIKEL LATERIT BERBASIS DATA HIPERSPEKTRAL DAN TOPOGRAFI DIGITAL DI PROSPEK TAPUNOPAKA, KABUPATEN KONAWE UTARA, PROVINSI SULAWESI TENGGARA

• Main Author: Purba Adryanto, Arnazt
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87237
• Institution: Institut Teknologi Bandung

Nickel demand is projected to increase until 2040, while the supply is anticipated to experience no significant increase starting in 2028, resulting in a potential nickel supply deficit. This looming deficit has spurred an increase in nickel exploration activities. However, early stages exploration activities possess a high risk. To address this issue, an economical exploration method is needed. Remote sensing can be applied in the early stages of exploration to identify potential mineral deposits, including nickel laterite. This study aims to determine the criteria for potential nickel laterite areas based on remote sensing using hyperspectral satellite images. Mineral mapping and feature classification were conducted using satellite spectral data. The target feature in this study is goethite, a mineral found in the nickel laterite zone near the surface. PRISMA hyperspectral satellite images acquired by the Italian Space Agency were used. The band ratio and unmixing methods were used to detect the goethite distribution. The band ratio method was used to define the goethite index anomaly. Additionally, the unmixing method was employed to separate goethite from surrounding features within a single pixel, as these fe -meter spatial resolution, so the feature classification in sub-pixels can be obtained. The band ratio based on the three equations used in the study gives a goethite index anomaly value of 1.6, 1.1, and 1.8 based on equations 1, 2, and 3. While the goethite probability criteria based on the unmixing is 0.8 (80%). The goethite mineral index as a band ratio result and goethite probability as an unmixing result evaluated using field data such as goethite content data from XRD results, laterite thickness, and laterite distribution show a good correlation. Correlation of band ratio and unmixing results to XRD goethite content gave R2 values of 0.7 and 0.8. Therefore, remote sensing analysis using the band ratio method and unmixing in this study provides effective results for the identification of goethite minerals as an indicator of laterite nickel deposits in the study area.