沖縄島附近海底發現大規模礦床

Last month the NHK News on-line reported the following:

沖縄沖の海底で大規模鉱床発見

4月10日 22時39分

沖縄本島の北西の沖合にある海底のくぼ地で、亜鉛や金などを大量に含んだ新たな鉱床、鉱物が集中的に集まる場所が発見され、当初想定されていた５００万トンの資源量を上回る可能性もあることから、今後の資源開発につながるとして期待されています。

新たな鉱床が見つかったのは、沖縄本島の北西およそ１００キロの沖合に位置する「伊是名海穴」と呼ばれる直径３キロから６キロの海底のくぼ地です。
独立行政法人の「石油天然ガス・金属鉱物資源機構」によりますと、国が策定した海底の鉱物資源開発計画に基づき、経済産業省の委託を受けて平成２０年度から伊是名海穴の海底調査を行っていて、ことし１月と２月、海底面から３０メートル以下の地底で亜鉛や金などを大量に含む新たな鉱床を発見したということです。
新たな鉱床の厚みや範囲はまだ不明だということですが、海底面付近ですでに確認されている鉱床の資源量がおよそ３４０万トンと見込まれていることから、新たな鉱床を含めると、伊是名海穴には当初想定されていた５００万トンの資源量を上回る大規模な金属鉱物資源が存在する可能性があるということです。
「石油天然ガス・金属鉱物資源機構」では、今後の資源開発につながるとして、新しい鉱床の全体の規模を把握するため、引き続き、海底での調査を続けるということです。

(試譯文)

It was new ore deposit containing zinc, gold etc. in large quantities: a place where minerals were gathering in large amount was discovered at a depressed ground of the seabed in the offing of the northwest of the main Okinawa island; since the resources might exceed 5 million tons that was originally assumed, it was expected that it might lead to future resources related development.

New ore deposit was found at the depressed ground of the seabed with a diameter of 3 to 6 km at the so called the "Izenakaiketsu" located in the offing about 100 km northwest of the main Okinawa island.

According to the "Oil, Gas and Metals National Corporation" which was an independent administrative agency, it was said that based on the mineral-resources  development plan of the seabed which the country had decided, seabed investigation on the Izenakaiketsu was performed staring from the Heisei 20^th year in response to Commission for the Ministry of Economy, Trade and Industry. In January and February this year a new ore deposit which was containing zinc, gold, etc. in large quantities was discovered below the seabed at depth of 30 meters below the sea water.

Although it was said that the thickness and the range of the new ore deposit were still unknown, because the resources of the ore deposit which was near the sea surface had already been checked and estimated at about 3,400,000 tons, when this new ore deposit was included, it was said that there might exist in the Izenakaiketsu a large-scale metallic mineral resources which could exceed the 5 million-ton estimation originally assumed.

In "Oil, Gas and Metals National Corporation" it was said that the investigation on the seabed was carried out continuously in order to grasp the scale of the whole new ore deposit, noting that it would lead to future resources development.

It is good news for Japan, the discovery would help its industrial development.