著者

渡辺 寧

出版者

資源地質学会

雑誌

資源地質 (ISSN:09182454)

巻号頁・発行日

vol.66, no.1, pp.27-34, 2016 (Released:2018-08-15)

参考文献数

27

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A future perspective of the supply of mineral resources is discussed on the basis of the example of rare earth elements (REE). Rare earth elements have been produced from monazite, bastnäsite, and ionic clay ores mostly in China during the last two decades. However, Chinese resource nationalism over the production and export has made the supply of REE unstable in terms of price and quantity. A possible alternative REE source is phosphate ores, which contain a few amount of REE as impurities with some toxic and radioactive elements. Despite low in REE concentration in phosphate ores, more than 300,000 tons of REE (as oxides), which correspond to more than two times of present-day REE demand in the world, are included in the ores annually produced from the mines for fertilizer production. The recovery of REE with other impurities from phosphate ores is beneficial not only to produce REE but also to avoid pollution in farming lands. While our society shifts from the plundering one to the sustainable one, in which mineral resources would be completely recycled, it is desired to recover all the by-product elements from the major ores in order to decrease the impacts on the environment and trigger innovations in the manufacturing industry.

著者

渡辺 寧

出版者

資源地質学会

雑誌

資源地質 (ISSN:09182454)

巻号頁・発行日

vol.60, no.2, pp.103-122, 2010 (Released:2013-06-14)

参考文献数

63

著者

鈴木 照洋 藤巻 勇帆 越後 拓也 渡辺 寧

雑誌

一般社団法人日本鉱物科学会2021年年会・総会

巻号頁・発行日

2021-08-11

著者

石澤 ほたか 越後 拓也 渡辺 寧

雑誌

一般社団法人日本鉱物科学会2021年年会・総会

巻号頁・発行日

2021-08-11

著者

実松 健造 星野 美保子 渡辺 寧

出版者

資源地質学会

雑誌

資源地質 (ISSN:09182454)

巻号頁・発行日

vol.62, no.1, pp.17-26, 2012 (Released:2013-08-01)

参考文献数

47

被引用文献数

3

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This study evaluates the potential of scandium resources in lateritic bauxite deposits and lateritic Ni-Co deposits derived from mafic parent rocks. Mafic rocks generally contain more Sc than felsic rocks because Sc replaces iron and manganese in pyroxene and amphibole. Pyroxenite and hornblendite are most enriched in Sc whereas peridotite is poor in Sc. Chemical weathering causes rocks to be enriched in Sc, which behaves as an immobile element, because mobile elements are leached from the rocks. Scandium contents of bauxite depend on those of parent rocks and they are estimated to be ~40 ppm in Indochina Peninsula. Red mud, Fe-rich residue in the process of refinery of bauxite, contains high concentration of Sc. Scandium-bearing lateritic Ni-Co deposits contain higher grades of Sc ores than bauxite and recently have been explored in Australia. As Sc contents of the laterite is controlled by those of parent rocks, pyroxenite-derived laterite may form high-grade Sc deposits (>100 ppm). However, Ni and Co grades tend to decrease in the high-grade deposits in Australia. Large amounts of resources and developed techniques in Sc recovery as a by-product indicate that bauxite deposits and lateritic Ni-Co deposits are prospective Sc resources in the near future.

著者

渡辺 寧

出版者

地学団体研究会

雑誌

地球科学 (ISSN:03666611)

巻号頁・発行日

vol.52, no.1, pp.55-56, 1998-01-25 (Released:2017-07-11)

著者

丸谷 雅治 東原 雅実 渡辺 寧 村上 浩康 小島 元 Boubou DIOUMASSI

出版者

The Society of Resource Geology

雑誌

資源地質 (ISSN:09182454)

巻号頁・発行日

vol.55, no.1, pp.59-70, 2005-05-20 (Released:2009-06-12)

参考文献数

23

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The mining sector in the Islamic Republic of Mauritania was the backbone of the country's economy in the 1960s when Mauritania gained independence from France. However, mineral exploration has been limited due to several factors including the limited availability of geological information, poor legal and fiscal framework and lack of mining sector promotion measures as well as the vast scale of the country, severe climate and lack of infrastructure.In response to the request of the Mauritanian Government, Japan International Cooperation Agency conducted "the Study on the Strategic Plan of Mineral Resource Development". A geological survey was implemented from November 2003 to March 2005 in the areas of mineral potential in Mauritania with the purpose of promoting domestic and foreign private investments in the exploration of mineral resources.Mauritania comprises five geological provinces. These are the Reguibat Shield, Taoudeni Sedimentary Basin, Tindouf Sedimentary Basin, Mauritanides and Atlantic-Coastal Sedimentary Basin. Major metal ore deposits are distributed within both the Reguibat Shield and the Mauritanides.In the central area of the Reguibat Shield, magnetite formations occur in the Archean groups and large-scale highgrade hematite banded-iron formations occur in the lower Proterozoic groups. These deposits are the sources of iron ores that support Mauritania economy. In the southwestern area of the shield, epithermal; and mesothermal gold-bearing quartz network and disseminated deposits (e.g.Tasiast gold deposit) occur in banded iron formations (BIFs) of the Archean greenstone belt. Moreover, gold-bearing quartz vein deposits (e.g.Tijirit Ator gold deposit) occur in the basalt and ophicalcite units.The Mauritanides is most significant in copper and gold mineralization among the five geological provinces. These comprise a carbonate replacement magnetite-bearing copper and gold deposits and prospects (e.g.Guelb Moghrein deposit), copper and gold-bearing quartz veins in mafic schist and carbonate (e.g.Tabrinkout prospect), copper (and gold)-bearing quartz veins in andesitic to basaltic volcanic rocks (e.g.Indice 78 and Oudelemguil prospects) and disseminated copper deposits (e.g.Kadiar). The other important deposit type is orthomagmatic PGE-bearing chromite deposits in serpentinite (e.g.Guidimaka).In the future, it is desirable that exploration and development focus on gold deposits in the Reguibat Shield, and copper and gold deposits and platinum-bearing chromite deposits in the Mauritanides.

著者

保柳 康一 三戸 望 吉岡 正俊 宮坂 省吾 渡辺 寧 松井 愈

出版者

地学団体研究会

雑誌

地球科學 (ISSN:03666611)

巻号頁・発行日

vol.39, no.6, pp.393-405, 1985-11-25

被引用文献数

6

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Thick Miocene sediments are distributed in the Ishikari-Teshio Belt along the western side of the Kitami mountain range in the north and the Hidaka mountain range in the south. In the southern part of this belt, the Miocene sequences are divided into the Furanui, Ukekoi, and Motokanbe Formations, in ascending order. The Furanui Formation (early Middle Miocene) consists mainly of greenish gray sandstones and mudstones The Ukekoi Formation (Middle Miocene) composed mainly of alternating beds of sandstone and mudstone and conglomerates, attains a maximum thickness of about 2,100 meters, which is correlated with the Kawabata Formation in the Ishikari district and the Kotanbetsu Formation in the Haboro district. The Motokanbe Formation (Late Miocene) consists mainly of hard shales and subordinate intercalated conglomerates. The Ukekoi Formation is subdivided lithologically into the U_1, U_2, and U_3 members in ascending order. The U_1 and U_3 are composed mainly of alternating beds of sandstone and mudstone with Bouma sequences, and the U_2 member consists of coarse clastic sediments with grading and imbrication structures developed well in the conglomerates. These facies are of turbidites and their related sediments. In the southern part of the studied area, these three members change laterally into the U4 member composed of alternating beds of sandstone and mudstone. The distribution pattern of these members can be assingned to the submarine fau environmental models of WALKER and MUTTI (1973) or WALKER (1978). The U_2 member is of the upper fan channel-fill deposits in the northern part of this area and of mid-fan deposits in the central part. The U_4 member in the southern part corresponds to the lower fan depoosits. The upper fan main channnel contains numerous smaller channels 10 meters or more deep and some 100 meters wide. These channels are filled with coarse clastic sediments transported from the north. On the basis of the above-mentioned discussion with the examination of the conglomerates, it is concluded that the Middle Miocene Ukekoi Formation is of submarine fan deposits transported far from the northern part of the Hidaka and Kamuikotan Belts, e. g. the Uenshiri Horst, while the Upper Miocene Motokanbe Formathionis of fan delta deposits derived from the eastern adjacent hinterland of the Hidaka Metamorphic Belt.

著者

渡辺 寧 村上 浩康 松枝 大治 吉田 武義 水田 敏夫 石山 大三 清水 正明 木村 純一 渡邊 公一郎 今井 亮 浦辺 徹郎 鹿園 直建 林 謙一郎 実松 健造 星野 美保子

出版者

独立行政法人産業技術総合研究所

雑誌

基盤研究(A)

巻号頁・発行日

2007

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世界各地の重希土類およびインジウム鉱床の調査を実施し,ベトナム,タイ等東南アジア地域で重希土類に富む花崗岩風化殻を発見するとともに,日本,中国,ベトナム,ペルー, ボリビアでのインジウムの資源量の見積もりを行った.これらの結果,中国以外の地域でも重希土類およびインジウムの資源ポテンシャルが存在することが判明し,また鉱床成因のための必要条件が考察された.