The Gypsum Deposits of the Hanaoka-Mine

Abstract

The Hanaoka-Mine is one of the typical black ore deposits and belongs to the so-called green tuff region of the Miocene, Tertiary.
The ore deposits consist chiefly of five kind of ores, that is, black ore (Sphalerite-galena-barite), yellow ore (Chalcopyrite-Pyrite), sulfide ore (Pyrite) and gypsum ore (Gypsum). There are some large scale gypsum ore deposits in the Haneoka-Mine.
The writer reports the some different occurrences of the three gypsum ore deposits, which are Bandai, Tutumi-zawa and Oishi-zawa gypsum ore deposit, from other metallic ore deposits in Hanaoka-Mine.
Generally speaking, thier occurrences, are follows. The large scale gypum ore deposits in Hanaoka-Mine
(1) have the N-S arrangement west of the Doyasiki deposit
(2) have up-lifted dome shaps
(3) don't accompany the white-coloured-rhyolite lava, as other metallic ore deposits in Hanaoka-Mine, in their lower horizon
(4) don't accompany relatively so amount of metallic ore on their uppermost
(5) have chlorite clay whenever they contain clay in them