Electronic Theses and Dissertation

Penelitian ini dilakukan di Desa Culambatu, Kecamatan Wiwirano, Kabupaten Konawe Utara, Sulawesi Tenggara, yang termasuk dalam Kompleks Ofiolit Sulawesi Timur. Penelitian ini bertujuan untuk mengetahui kondisi geologi dan geomorfologi, karakteristik serta zonasi endapan nikel laterit, hubungan kemiringan lereng terhadap ketebalan laterit, serta melakukan pemodelan geologi 3D dan estimasi sumber daya. Metode yang digunakan meliputi pemetaan geologi dan geomorfologi, analisis petrografi, pengolahan data pemboran, domaining zona laterit, analisis hubungan lereng dan ketebalan laterit, pemodelan geologi 3D menggunakan Leapfrog, estimasi kadar dengan Ordinary Kriging, dan pembuatan block model. Hasil penelitian menunjukkan bahwa daerah penelitian tersusun atas Satuan Peridotit, Satuan Batulempung, dan Satuan Batupasir. Satuan Peridotit berperan sebagai batuan induk endapan nikel laterit dan berdasarkan analisis petrografi termasuk harzburgit terserpentinisasi. Profil laterit terbagi menjadi zona limonit, saprolit, dan bedrock. Analisis lereng menunjukkan hubungan negatif terhadap ketebalan laterit, dengan nilai korelasi Pearson -0,384 dan persamaan regresi Y = 40,159 - 0,184X. Hasil estimasi sumber daya menunjukkan tonase limonit sebesar 32.080.312,5 ton dengan kadar Ni rata-rata 0,955%, sedangkan saprolit sebesar 13.471.000 ton dengan kadar Ni rata-rata 0,943%. Total estimasi sumber daya nikel laterit adalah 45.551.312,5 ton dengan kandungan logam Ni sebesar 433.355,25 ton. Hasil ini merupakan estimasi sumber daya pendekatan karena densitas yang digunakan merupakan densitas asumsi.

The study was conducted in Culambatu Village, Wiwirano District, North Konawe Regency, Southeast Sulawesi, Indonesia, which is part of the East Sulawesi Ophiolite Complex. This research aims to determine the geological and geomorphological conditions, characterize and delineate the zonation of nickel laterite deposits, analyze the relationship between slope gradient and laterite thickness, and develop a 3D geological model for resource estimation. The research methods included geological and geomorphological mapping, petrographic analysis, drillhole data processing, laterite domain modeling, slope–laterite thickness relationship analysis, 3D geological modeling using Leapfrog, grade estimation using the Ordinary Kriging method, and block model generation. The results indicate that the study area is composed of Peridotite, Mudstone, and Sandstone Units. The Peridotite Unit serves as the parent rock of the nickel laterite deposit and is identified through petrographic analysis as serpentinized harzburgite. The laterite profile is divided into limonite, saprolite, and bedrock zones. The slope analysis reveals a negative relationship between slope gradient and laterite thickness, with a Pearson correlation coefficient of -0.384 and a regression equation of Y = 40.159 − 0.184X. Resource estimation results indicate a limonite resource of 32,080,312.5 tonnes with an average nickel grade of 0.955% Ni, while the saprolite resource is estimated at 13,471,000 tonnes with an average nickel grade of 0.943% Ni. The total estimated nickel laterite resource is 45,551,312.5 tonnes, containing approximately 433,355.25 tonnes of nickel metal. These results represent a preliminary resource estimate because the density values applied in the estimation were based on assumed densities rather than measured bulk density data.