Analysis of Laterite Nickel Distribution Using the Ground Penetrating Radar (GPR) Method in Kolaka Regency

Laterite nickel ore is the primary source of nickel in Indonesia, formed through the weathering of ultramafic rocks. The exploration of laterite nickel is essential to support the growing demand of the nickel industry. Ground Penetrating Radar (GPR) is used as a non-destructive and efficient alternative method to identify subsurface conditions of laterite nickel deposits based on variations in dielectric constants and electromagnetic wave reflection patterns. GPR measurements were conducted along nine survey lines in Block xxx, Kolaka Regency, Southeast Sulawesi. Data processing involved several filtering techniques and topographic corrections to produce radargram cross-sections, which were then correlated with borehole data to achieve more accurate and comprehensive interpretations. The correlation results indicate that the GPR method can successfully identify laterite nickel layers, including limonite, saprolite, and bedrock. The thickness of the limonite layer ranges from 3.3 to 12.3 meters, while the saprolite layer varies between 3.1 to 20 meters. Based on estimation calculations within the study area, a significant nickel resource potential of approximately 1,236,385 tons was identified. This study demonstrates that the GPR method is effective for preliminary exploration of laterite nickel deposits, offering advantages in terms of cost and time efficiency compared to other methods.