International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2015): 78.96 | Impact Factor (2015): 6.391 Volume 6 Issue 4, April 2017 www.ijsr.net Licensed Under Creative Commons Attribution CC BY 3D Block Model of Elements Distribution in Laterite Nickel Deposits Andi Ilham Samanlangi Email: Andhis79[at]yahoo.com Mining Engineering, Engineering Faculty, Universitas Pejuang RI Makassar Abstract: This study aimed to determine the 3-dimensional block model of elements in laterite nickel deposit. The method used in this study included drilling data, then analyzed using X-RF to get value of the element and grade from laterite nickel and ArcGIS program used to model the distribution of nickel elements laterally. The study concluded that in the block model, distribution of Ni colored yellow indicating Ni grade range from 0 to 1.2%, red color from 1.2-1.5, blue color from 1.5 to 1.8 and green color > 1, 8% of Ni grade. In block model of Fe distribution colored blue indicating Fe grade range from 3.15 to 10.25%, yellow color from 10.25 to 25.14%, green color from 25.14 to 35.69%, and brown color > 35,69% of Fe grade. In block model of MgO distribution colored red indicating MgO grade range from 0.25 to 10%, blue color 10-20%, yellow 20-30%, and green color > 30% of MgO grade. In block model of Co distribution colored yellow indicating Co grade range from 0-0.1%, green color 0.1-0.2%, red color 0.2-0.3%, and blue color > 0.3% of Co grade. In block model of SiO 2 distribution indicating SiO 2 grade range from 1-15%, green color 15-30%, yellow color 30-45% ,and blue color > 45% of SiO 2 grade. Elements distribution vertically indicated the degree of variation and mobility difference of the elements. Ni, MgO and SiO 2 tended to be concentrated in the saprolite zone while Fe and Co tended to be concentrated in the limonite zone. Keywords: Nickel, Distribution Elements, 3D Models, ArcGIS, X-RF 1. Introduction Indonesia has very abundant natural resources including mineral resources, so it always becomes a target for investment in mining. As we know that investments in mining require not little cost even very much. Therefore, in the process of exploration require great accuracy and responsibility for reducing the risk of losses that can be obtained. After the exploration stage, modeling and estimation of resource or reserve need to be performed very carefully and responsibly. Deposit modeling aims to provide an overview about geological conditions and geometrical characteristics of deposit, so require analysis of the ore body models to determine the mine method. Estimation of resources or reserves are also performed to determine the quantity of deposit that considered be economical to mine. So in this stage, require a method that can provide approach with the total of existing resources or reserves. 2. Basic Theory Sulawesi Island is located on convergent zone among three lithosfer plates, they are Hindia-Australia plate that moves to the north, Pacific plate moves to the west, and Eurasia plate in the north side of Sulawesi Island moves to the south. (Herman and Hasan Saidi, 2000) According to Hamilton (1979), based on lithology association dan tectonic development, Sulawesi Island and around divided into 5 tectonic provinces, they are: (1) West Sulawesi Tertiary Volcanis Arc, (2) Minahasa- Sangihe Volcanic Arc, (3) Central Sulawesi Cretaceous- Paleogene Metamorphic Belt Associated Pelagic Sediment, (4) East Sulawesi Creataceous Ophiolite Belt, (5) Banggai-Sula Microcontinent Fragment derived from Australia continent. Regional Geology of Study Area In general, study area included East Sulawesi geology province, which was characterized by a set of metamorphic rocks, serpentinite, gabbro, basalt and pelagos Mesozoic sedimentary rocks (Sukamto, 1981). The rocks exposed in the area of inventory activities ranging from Paleozoic to Quaternary, according to Rusmana E., et al. (1993). Geomorphology Regionally, study area included in the geological map of Lasusua - Kendari located in the southeast arm of Sulawesi Island. Morphology of Lasusua - Kendari could be divided into four units, namely the mountains, hills, karst area, and lowland (Rusmana, et al, 1993). Genesis of Laterite Nickel Deposit Nickel laterite is a residual product of the chemical weathering of ultramafic rocks. This process occured for millions of years, started when the ultramafic rocks exposed on the surface of the earth. Weathering on the peridotite caused elements with low mobility to immobile as Ni, Fe and Co were enriched residually and secondarily (Burger, 1996). Based on its formation process, lateritic nickel deposit was divided into several zones with varying thickness and grade. Zones with intensive jointing intensity perhaps would have thicker profile than those less intensive of jointing. Weathering is very closely related to the chemical and physical processes that vertically is a profile description of ultramafic rocks change become laterite deposit. Profile change of ultramafic rocks included paleotopography Paper ID: ART20171430 DOI: 10.21275/ART20171430 1728