Electronic Theses and Dissertation

Permintaan global terhadap nikel terus meningkat seiring berkembangnya industri kendaraan listrik dan baja tahan karat. indonesia merupakan negara dengan cadangan nikel terbesar di dunia, salah satunya berada di kabupaten konawe utara, sulawesi tenggara. daerah penelitian berada pada wilayah iup pt antam tbk. dengan luas sekitar ±4 km² dan tersusun oleh kompleks ultramafik ofiolit sulawesi yang telah mengalami proses serpentinisasi dan pelapukan laterit. penelitian ini bertujuan untuk mengetahui kondisi geologi daerah penelitian serta menganalisis pengaruh serpentinisasi terhadap pengayaan nikel (ni) pada zona saprolit. metode yang digunakan meliputi pemetaan geologi, analisis petrografi, analisis geokimia x-ray fluorescence (xrf), analisis korelasi pearson, pemodelan peta isograde berdasarkan data 10 titik bor, serta data x-ray diffraction (xrd) dari penelitian sebelumnya. hasil penelitian menunjukkan bahwa daerah penelitian tersusun oleh satuan kompleks ultramafik dan aluvium, dengan litologi utama berupa peridotit (lherzolite) dan dunit yang telah mengalami serpentinisasi. kadar ni pada zona bedrock berkisar antara 0,22–0,41%, sedangkan pada zona saprolit meningkat menjadi 0,55–1,63%. hasil petrografi menunjukkan bor-9 dengan vein tipe 1 memiliki kadar ni tertinggi sebesar 1,63%, sedangkan bor-5 dengan vein tipe 3 memiliki kadar ni sebesar 1,01%. peta isograde menunjukkan peningkatan kadar ni dari bagian barat ke timur daerah penelitian. berdasarkan hasil penelitian, serpentinisasi berperan sebagai proses pelepasan ni dari mineral primer pada batuan ultramafik yang memperkaya area sekitarnya, pada saat terjadinya proses serpentinisasi saat terakumulasi ulang pada zona retakan, hubungan antara serpentinisasi dan pengayaan ni bersifat non-linear, di mana kondisi serpentinisasi menengah merupakan kondisi yang paling optimum dalam menghasilkan kadar ni tertinggi pada daerah penelitian.

Global demand for nickel continues to increase along with the rapid growth of the electric vehicle and stainless steel industries. Indonesia is recognized as the country with the largest nickel reserves in the world, one of which is located in North Konawe Regency, Southeast Sulawesi. The study area is situated within the Mining Business Permit (IUP) area of PT ANTAM Tbk., covering approximately ±4 km², and is composed of the Sulawesi Ophiolite Ultramafic Complex that has undergone serpentinization and lateritic weathering processes.This study aims to determine the geological conditions of the research area and analyze the influence of serpentinization on nickel (Ni) enrichment within the saprolite zone. The methods applied include geological mapping, petrographic analysis, X-Ray Fluorescence (XRF) geochemical analysis, Pearson correlation analysis, isograde map modeling based on data from 10 drill holes, and X-Ray Diffraction (XRD) data from previous studies.The results indicate that the study area consists of the Ultramafic Complex unit and Alluvium unit, with the main lithologies represented by serpentinized peridotite (lherzolite) and dunite. Nickel content in the bedrock zone ranges from 0.22–0.41%, while in the saprolite zone it increases significantly to 0.55–1.63%. Petrographic analysis shows that BOR-9, characterized by Type 1 veins, contains the highest Ni grade of 1.63%, whereas BOR-5, characterized by Type 3 veins, contains a Ni grade of 1.01%. Isograde mapping demonstrates an increase in Ni concentration from the western to the eastern part of the study area.Based on the results, serpentinization plays a role in releasing Ni from primary minerals within ultramafic rocks, allowing subsequent redistribution and re-accumulation around surrounding areas, particularly within fracture zones. The relationship between serpentinization and Ni enrichment is non-linear, where moderate serpentinization conditions represent the most optimal stage for generating the highest nickel concentration within the study area.