북동태평양 Clarion-Clipperton 해역 표층 퇴적물의 희토류 조성 및 희토류 광상으로서의 잠재성 = Composition of Rare Earth Elements in Northeast Pacific Surface Sediments, and their Potential as Rare Earth Elements Resources

다국어 초록 (Multilingual Abstract)

The surface sediments from the manganese nodule exploration area of Korea in the Clarion-Clipperton fracture zone were investigated to understand the resource potential of and emplacementmechanism for rare earth elements (REEs). The sediments are categorized into three lithological units (UnitI, II and III from top to bottom), but into two groups (Unit I/II and Unit III) based on the distribution pattern of REEs. The distribution pattern of REEs in Unit I/II is similar to that of Post-Archean Australian Shale(PAAS), but shows a negative Ce anomaly and enrichment in heavy REEs (HREEs). In Unit III, the HREE enrichment and Ce anomaly is much more remarkable than Unit I/II when normalized to PAAS, which areinterpreted as resulting from the absorption of REEs from seawater by Fe oxyhydroxides that were transported along the buoyant plume from remotely-located hydrothermal vents. It is supported by thePAAS-normalized REE pattern of Unit III which is similar to those of seawater and East Pacific Rise sediments. Meanwhile, the PAAS-normalized REE pattern of Unit I/II is explained by the 4:1 mixing ofterrestrial eolian sediment and Unit III from each, indicating the much smaller contribution of hydrothermal origin material to Unit I/II. The studied sediments have the potentiality of a low-grade and large tonnage REE resource. However, the mining of REE-bearing sediment needs a large size extra collecting, lifting and treatment system to dress and refine low-grade sediments if the sediment is exploited with manganese nodules. It is economically infeasible to develop low-grade REE sediments at this moment in time because the exploitation of REE-bearing sediments with manganese nodules increase the mining cost.

참고문헌 (Reference)

1 박상준, "한국이 탐사 중인 해저광물자원의 희유금속 함량과 의미" 대한자원환경지질학회 43 (43): 455-466, 2010

2 Mills RA, "dual origin for the hydrothermal component in a metalliferous sediment core from the Mid-Atlantic Ridge" 98 (98): 9671-9681, 1993

3 Ruhlin DE, "The rare earth element geochemistry of hydrothermal sediments from the East Pacific Rise: Examination of a seawater scavenging mechanism" 50 (50): 393-400, 1986

4 Boström K, "The origin of aluminumpoor ferromanganoan sediments in areas of high heat flow on the East Pacific Rise" 7 (7): 427-447, 1969

5 Taylor SR, "The geochemical evolution of the continental crust" 33 (33): 241-265, 1995

6 Lupton JE, "Seafloor Hydrothermal Systems: Physical, Chemical, Biological, and Geological Interactions" American Geophysical Union 317-346, 1995

7 Mills RA, "Seafloor Hydrothermal Systems: Physical, Chemical, Biological, and Geological Interactions" American Geophysical Union 392-407, 1995

8 Humphries M, "Rare earth elements: The global supply chain" Congressional Research Service 2010

9 Elderfield H, "Rare earth element geochemistry of oceanic ferromanganese nodules and associated sediments" 45 (45): 513-528, 1981

10 Dickens GR, "Rare earth element deposition in pelagic sediment at the Cenomanian-Turonian boundary, Exmouth Plateau" 22 (22): 203-206, 1995

11 Wu C, "Rare earth deposits in China. In Jones AP, Wall F, Williams CT (eds) Rare earth minerals: Chemistry, origin and ore deposits" 7 : 281-310, 1996

12 Kawamoto H, "Policies to be adopted on Rare Metal Resources" 27 : 57-76, 2008

13 Hyeong K, "Mineralogical and geochemical compositions of the eolian dust from the northeast equatorial Pacific and their implications on paleolocation of the Intertropical Convergence Zone" 20 : PA1010-, 2005

14 KIGAM, "Mineralization and feasibility study of Fe-REE deposits in Hongcheon area" 257-, 2001

15 "Metal-Pages"

16 Banerjee R, "Manganese nodules as a possible source of precious metals" 87 : 278-279, 2004

17 Castor SB, "Industrial Minerals and Rocks" Society for Mining, Metallurgy and Exploration 769-792, 2006

18 Hein JR, "Handbook of Marine Mineral Deposits" CRC Press 239-279, 2000

19 Hein JR, "Global occurrence of tellurium-rich ferromanganese crusts and a model for the enrichment of tellurium" 67 (67): 1117-1127, 2003

20 Owen RM, "Geochemistry of rare earth elements in pacific hydrothermal sediments" 25 (25): 183-196, 1988

21 German CR, "Elderfield H(1990)Hydrothermal scavenging of rareearth elements in the ocean" 345 (345): 516-518, 1990

22 Kato Y, "Deepsea mud in the Pacific Ocean as a potential resource for rare-earth elements" 4 (4): 535-539, 2011

23 Nikolaev AI, "Choosing the technology of combined processing of titanium-raremetal raw materials" 42 : 675-679, 2008