Mining in Japan

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Japanese archipelago and the seabed Japan Relief Map of Land and Seabed.png
Japanese archipelago and the seabed

Mining in Japan is minimal because Japan does not possess many on-shore mineral resources. [1] Many of the on-shore minerals have already been mined to the point that it has become less expensive to import minerals. There are small deposits of coal, oil, iron and minerals in the Japanese archipelago. [2] Japan is scarce in critical natural resources and has been heavily dependent on imported energy and raw materials. [3] [2] There are major deep sea mineral resources in the seabed of Japan. This is not mined yet due to technological obstacles for deep sea mining. [4]

Contents

In 2019, Japan was the 2nd largest world producer of iodine, [5] 4th largest worldwide producer of bismuth, [6] the world's 9th largest producer of sulfur [7] and the 10th largest producer of gypsum. [8]

History

The Japanese archipelago is in a subduction zone with great tectonic plate movement. The Philippine Sea Plate moves beneath the continental Amurian Plate and Okinawa Plate to the south. The oceanic Pacific Plate moves under the continental Okhotsk Plate to the north. These subduction plates have pulled Japan eastward and opened the Sea of Japan by back-arc spreading around 15 million years ago. [9] It has uplifted the Japanese islands and created three oceanic trenches: the Kuril–Kamchatka Trench, Japan Trench and Izu–Ogasawara Trench. [10] This has produced a wide variety of mineral resources, though not in large quantities on-shore. Most resources are in the seabed.

During the Meiji period, mine development was promoted under the policy of the Fengoku Robe (足尾銅山), and coal mining, Ashio Copper Mine, and Kamaishi Mine (釜石鉱山) with iron ore in Hokkaido and northern Kyushu were developed. The production of high-value gold and silver, even in small quantities, was at the top of the world. An important mine was the Ashio Copper Mine which existed since at least the 1600s. It was owned by the Tokugawa shogunate. At that time it produced about 1,500 tons annually. The mine was closed in 1800. In 1871 it became privately owned and reopened when Japan industrialized following the Meiji Restoration. By 1885 it produced 4,090 tons of copper (39% of Japan's copper production). Due to a lack of regulations it caused substantial pollution. [11] In 1911, the government passed the Factory Law which was Japan's first law to address industrial pollution. [12] It was closed again in 1973.

Until the 1960s, during a period of high economic growth, active mining continued at mines in various regions. However, large-scale mining was difficult, with mixed quality, and cost were high. So foreign resources with low cost and good quality were imported. This resulted in closures of mines in Japan.

Until the 1970s, all over Japan were mines, oil, natural gas (although a small amount) and coal including gold, silver, copper, iron, zinc mining was done on a large scale. After the period of high economic growth, in addition to resource depletion or lower grades, the mining cost rose and price competitiveness was lost so many mines stopped operations.

The Japanese mining industry began to rapidly decline in the 1980s.[ not verified in body ] Coal production shrank from a peak of 55 million tons in 1960 to slightly more than 16 million tons in 1985, while coal imports grew to nearly 91 million tons in 1987. Domestic coal mining companies faced cheap coal imports and high production costs, which caused them chronic deficits in the 1980s. In the late 1980s, Japan's approximately 1 million tons of coal reserves were mostly hard coal used for coking. Most of the coal Japan consumed is used to produce electric power.[ not verified in body ]

In the 21st century, mining has only been carried out in the Kushiro Coal Field (釧路炭田) for technology transfer. Other mines have lost their price competitiveness due to resource depletion, degrading quality, and increased mining costs including labor costs so many mines closed. Only a small number of mines are operational.

Since gold and silver is highly profitable even in small quantities, metal mining corporations continue to conduct systematic exploration and operations such as the discovery of the Hishikari mine. The Hishikari mine has an estimated reserves of 8 million oz of gold. [13] In addition, sulfur, iodine, limestone and quartzite are still sufficiently mined in Japan.

According to the Canadian Trade Commission for Japan: "In 2012, the Government of Japan increased the credit line for the Japan Bank for International Cooperation (JBIC) by 10 trillion yen (approximately C$105 billion) to further enable the Japanese private sector to secure strategic natural resources, and expanded JBIC's mandate to provide financial assistance for certain types of natural resource development projects in developed countries. Although this initiative has ended in June 2016, JBIC will continue this initiative to support the Japanese FDI opportunities in natural resources sector." [1] [ citation needed ]

The country lacks significant domestic reserves of fossil fuel, except coal. Thus Japan imports substantial amounts of crude oil, natural gas, and other energy resources, including uranium. Japan relied on oil imports to meet about 84 percent of its energy needs in 2010. [14] Japan was the first coal importer in 2010, with 187 Mt (20% of total world coal import), and the first natural gas importer with 99 bcm (12.1% of world total gas import). [15]

The seabed of Japan has major mineral resources. [4] In April 2018, it was reported that mud from the seabed off the island Minami-Tori-shima, some 1,150 miles southeast of Tokyo, contains more than 16 million tons of rare-earth oxides. [16] This was reported to be the equivalent to 780 years' worth of yttrium supply, 620 years of europium, 420 years of terbium and 730 years of dysprosium, at current rates of global usage. [16]

Japanese fuels production (19161945)

Coal deposits

In 1925, Japan's Mining Office referred to coal reserves in the empire of 8,000 million tonnes, or 2,933 million tonnes (Kyūshū, Miiki and Mitsui deposits), 2,675 or 3,471 million tonnes (Hokkaidō, ones 1,113,600 million from Yubari mine), 1,362 million tonnes (Karafuto, in Kawakami deposits), 614 million tonnes (Honshū), 385 million tonnes (Formosa, in the Kirun area), 81 million tonnes (Korea). Extraction in Japan during 1912 was 20,000,000 tonnes, in 1932 in 30,000,000 tonnes and grew in 1941 to 55,500,000 tonnes and was divided between the following sources, in tonnes: Korea (5,000,000), Formosa (2,500,000) and Karafuto (2,500,000) and additional imports 4,000,000 tonnes from China and Indochina.[ citation needed ]

Japanese coal is found in the extreme ends of the country, in Hokkaidō and Kyūshū, which have, respectively, 45 and 40 percent of the country's coal deposits. Kyūshū's coal is generally of poor quality and hard to extract, but the proximity of the Kyūshū mines to ports facilitates transportation. In Hokkaido, the seams are wider, can be worked mechanically, and offer a higher-quality coal. Unfortunately, these mines are located well inland, making transportation difficult. In most Japanese coal mines, inclined galleries, which extended in some places to 9.71 kilometers underground, were used instead of pits. This arrangement is costly, despite the installation of moving platforms. The result is that a miner's daily output is far less than in Western Europe and the United States, thus domestic coal costs far more than imported coal.[ citation needed ]

As the coal mining industry declined, so did the general importance of domestic mining to the whole economy. Only 0.2% of the labour force was engaged in mining operations in 1988 and the value added from mining was about 0.3% of the total for all mining and manufacturing. Domestic mining production supplies an important quantity of some nonmetals: silica sand, pyrophyllite clay, dolomite, and limestone. Domestic mines are contributing declining shares of the country's requirements for some metals: zinc, copper, and gold. Almost all of the ores used in the nation's sophisticated processing industries are imported. [17]

Oil sources

In 1925, the local petroleum reserves were estimated at 2,956,000 barrels in the Niigata, Akita and Nutsu deposits and, additionally, at Sakhalin concessions. In 1941, Japanese petroleum production was 2,659,000 barrels — about the daily production in the U.S., and 0.1% of world petroleum production. In Manchukuo, oil wells gave Japan 1,000,000 of additional petroleum tonnes per year. The local oils fields of Akita, Niigata and Nutsu produced 2,659,000 barrels. Additionally, they obtained oil in Formosa (1,000,000), Soviet Sakhalin (1,000,000) and the Manchu oil distillery process.[ citation needed ]

Oil wells have been drilled off the west coast of Honshū and Japan has oil concessions in North Sakhalin. Iron is scarce outside of Hokkaidō and northwest Honshū, and iron pyrite has been discovered in Honshū, Shikoku and Karafuto. A modest quantity of copper and gold is mined around Honshū, Hokkaidō and Karafuto.[ citation needed ]

As of 2016, remaining active oil fields are:

Natural gas

Significant natural gas reserves remain in:

Metal production locations

Production of copper in 1917 was 108,000 tonnes, in 1921 54,000 tonnes, in 1926 63,400 tonnes but this production was augmented to 70,000 tonnes in 19311937.[ citation needed ] Gold production in Korea was 6.2 ton in 1930 rising to 26.1 ton/year at peak. In rivers and mines, other deposits were in Saganoseki (Ōita) Honshū, Kyushu, and North Formosa. Also, Japan imported gold from overseas.

Other important iron sources were Muroran (Hokkaidō) and Kenji (Korea). Total reserves were 90 M tonnes of their own, 10 M or 50 M in Korea (Kenjiho) and Formosa. Japan imported iron from Tayeh (China), 500,000 tonnes in 1940, from Malacca, Johore and other points, 1,874,000 tonnes, from Philippines 1,236,000 tonnes, India sent 1,000,000 tonnes and 3,000,000 processed iron in bars and Australia sent a similar quantity.[ citation needed ] The principal silver mines were in Kosaki, Kawaga and Hitachi, and others in Karafuto with Iron Pyrite.

The production of gold was curbed in 1943 by Order for Gold Mine Consolidation to concentrate on the minerals more critical for the munitions production.

Metal sources

Cobalt, Copper, Gold, Iron, Lead, Manganese, Silver, Tin, Tungsten and Zinc are common [ citation needed ] and were extensively mined in Japan.

Barium, Berillium, Bismuth, Cadmium, Chromium, Indium, Lithium, Mercury, Molybdenum, Nickel, Titanium, Uranium and Vanadium are uncommon but still were mined in Japan.

Non-metal elemental sources

Antimony, Arsenic, Boron, Germanium, Graphite and Sulphur were all mined in Japan.

Complex mineral sources

Japan has a history of mining deposits of:

Deep sea mining

Japan has the 8th largest Exclusive Economic Zone of 4,470,000 km2 (1,730,000 sq mi). There are estimated large quantities of mineral resources such as methane clathrate, natural gas, metallic minerals and rare-earth mineral reserves stored in Japan's EEZ. Seabed mineral resources such as manganese nodules, cobalt-rich crust and submarine hydrothermal deposits are located at depths over 1,000 m (3,300 ft). [4] Most of these deep sea resources are unexplored at the seabed. Much of the seabed has a depth of 3,000 m (9,800 ft) to 6,000 m (20,000 ft). Japan's mining law restricts offshore oil and gas production. There are technological hurdles to mine at such extreme depths and to limit the ecological impact. There are no successful commercial ventures that mine the deep sea yet. So currently there are few deep sea mining projects to retrieve minerals or deepwater drilling on the ocean floor.

It is estimated that there are approximately 40 trillion cubic feet of methane clathrate in the eastern Nankai Trough of Japan. [22] As of 2019, the Methane clathrate in the deep sea remains unexploited, because the necessary technology is not established yet. This is why currently Japan has very limited proven reserves like crude oil.

The Kantō region alone is estimated to have over 400 billion cubic meters of natural gas reserves. It forms a Minami Kantō gas field in the area spanning Saitama, Tokyo, Kanagawa, Ibaraki, and Chiba prefectures. However, mining is strictly regulated in many areas because it is directly below Tokyo, and is only slightly mined in the Bōsō Peninsula. In Tokyo and Chiba Prefecture, there have been frequent accidents with natural gas that was released naturally from the Minami Kantō gas field. [23]

In March 2013, the Japan Oil, Gas and Metals National Corporation (JOGMEC) became the first to successfully extract methane hydrate from seabed deposits. [24] [25]

In 2018, 250 km (160 mi) south of Minami-Tori-shima at 5,700 m (18,700 ft) deep, approximately 16 million tons of rare-earth minerals were discovered by JAMSTEC in collaboration with Waseda University and the University of Tokyo. [26]

On December 21, the Government of Japan decided to limit access to offshore rare earth deposits within the EEZ to only approved miners with a license of the Ministry of Economy, Trade and Industry. [27] Japanese law will be updated to include regulations for domestic rare earth mining. [27] JOGMEC will be permitted to invest up to 75% in mining projects and mineral-refining operations. [27]

See also

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