PETROGRAPHY AND HYDROTHERMAL ALTERATION OF ULTRAMAFIC BED-ROCKS OF SOUTH SIPILOU: IMPLICATION IN THE LATERITIC NICKEL MINERALIZATION (DEPARTMENT OF SIPILOU, WESTERN IVORY COAST)

South Sipilou is an area containing lateritic nickel mineralization that developed on ultramafic rocks in the department of Sipilou-Biankouma western Ivory Coast. The objective this study was to characterize petrography and hydrothermal alterations affecting these bed-rocks understand their involvement mineralization. Then compare them already characterized Sipilou-Biankouma. Thus, macroscopic characterization carried out field. Then, microscopic observations were made after preparation thin sections laboratory.The results indicated lithologies consist strongly serpentinized dunites, more or less harzburgitic lherzolites olivine orthopyroxenites. Their petrographic characteristics showed a similarity with nickel-bearing North Biankouma, differences those Samapleu, Yepleu, Also, main are composed silicification, carbonation serpentinization. Only serpentinizationcontributed concentration bed-rock within profile.