釜石鉱山における最近の探査
特に第7鉱体の発見について
1966 年 16 巻 76-77 号 p. 116-123
詳細
1966 年 16 巻 76-77 号 p. 116-123
The Kamaishi mine is well known as one of the typical contact-pyrometasomatic iron and copper deposits in Japan. Recently, No. 7 ore body was found in the Shinyama deposit by tracing the contact zone of limestone lenses and igneous rocks. The ore body shows the following characteristics:
In the upper part, there occurs a large amount of skarn minerals, and the nature of the ore body is almost the same as that of the other iron-copper deposits in the mine, but a copper-rich zone with green skarn occurs along the limestone in the middle part.
In the lower part, a skarnized zone between limestone and igneous rock is very narrow in width, in which high-grade magnetite ore and chalcopyrite ore are deposited with relatively small amounts of skarn minerals.
Formation of the iron-rich zone is controlled by the form of igneous rocks. Copper-rich zone is on the same horizon as No.4 copper ore body, and it sometimes branches out, forming some small ore bodics along dyke rocks.
