NICKEL ELEMENT CONTENT DISTRIBUTION IN LATERITE DEPOSITS BASED ON GEOCHEMISTRY USING THE INVERSE DISTANCE WEIGHTING (IDW) METHOD

Abstract

Administratively, the study area is located in the Sorowako Area, Nuha Sub-district, East Luwu  District,  South  Sulawesi  Province,  Indonesia.  Inverse  Distance  Weighting  is  a method  used  to  determine  the  distribution  of  Ni  element,  which  is  one  of  the geocomputation  methods  that  uses  the  concept  that  the  value  at  a  location  can  be estimated based on how close the location is to existing measured points, with weights given based on the distance. The data used in this study is geochemical data from XRF analysis results on laterite samples in the study area. XRF analysis results show that the Ni content value in the limonite zone tends to be lower than in the saprolite zone, which is caused by the semi-mobile nature of the Ni element, so that the Ni element accumulates in the saprolite zone as a result of the enrichment process. The XRF method was used in the geochemical analysis of the laterite deposit samples, which showed high Ni content in the saprolite zone compared to the limonite zone. Ni distribution in the limonite zone is found in two classes of grade distribution, which are < 1.3% and 1.3% - 1.5%. While in the saprolite zone tends to be more varied, there are six classes of grade distribution, from grade values < 1.3% to > 2.25% distributed in the study area.