Occurrence and chemical composition of chlorite in Toyoha hydrothermal system, southwest Hokkaido

Abstract

Chlorite associated with the ore mineralization at Toyoha epithermal ore deposit is well-known to be rich in Fe and Mn. However, the genesis is poorly understood. In this study we work on the hydrothermal alteration near the deposit using drill cores TH-2~7, which were drilled by NEDO. We paid special attension to the occurrence and chemical composition of chlorite and carbonate minerals and based on the result we will talk about the genesis of chlorite mineralization and its relationship to the ore mineralization.