Deep-sea rare earth resource potential in the Eastern Pacific Clarion-Clipperton Fracture Zone: Constraint from sediment geochemistry

doi:10.3969/j.issn.1001-909X.2023.04.005

Abstract

Abstract:

Deep-sea sediments have attracted much more attention in recent years because of their potential resources for rare earth elements plus Yttrium (REY). However, the host minerals and enrichment mechanism of REY in deep-sea sediments, and the spatial distribution characteristics and metallogenic regularity of the REY-rich sediments are still unclear. The Clarion-Clipperton Fracture Zone (CCZ) in the East Pacific is the most important polymetallic nodule metallogenic belt, and its potential of REY resources has not been well evaluated. In this study, the whole-rock geochemistry (728 groups of major elements and 625 groups of trace elements) of sediments from 125 stations in the west CCZ over an area of 27 800 km² was analyzed. The results show that the sediments in the study area are significantly rich in MnO, P₂O₅ and REY than those from Australian shales and global subducting sediments. Spatially, ∑REY has a positive correlation with P₂O₅, CaO, and Ce negative anomalies, indicating that calcium apatite is the main host minerals of REY. The average value of ∑REY in the sediments over the study area is 470±202 μg/g, some samples meet the criteria of REY-rich sediments (∑REY>700 μg/g), indicating that the study area has a certain potential of REY resources. Spatial interpolation analysis shows that REY-rich sediments are mainly distributed in the northern area characterized by hilly terrain, while they are poorer in the southern basin with flat terrain. The difference of geomorphology in the study area affects the regional deposition rate and the hydrodynamic sorting of calcium apatite, leading to the north-south zoning of REY resources distribution in the study area.

Key words: deep-sea sediments, rare earth elements and Y (REY), calcium apatite, resource potential, Clarion-Clipperton Fracture Zone (CCZ)

CLC Number:

P736.2

WU Xinran, DONG Yanhui, LI Zhenggang, WANG Hao, ZHANG Weiyan, LI Huaiming, LI Xiaohu, CHU Fengyou. Deep-sea rare earth resource potential in the Eastern Pacific Clarion-Clipperton Fracture Zone: Constraint from sediment geochemistry[J]. Journal of Marine Sciences, 2023, 41(4): 46-56.

Figures/Tables 9

Fig.1 Tectonic location (a) and topography (b) of the study area (Fig.a indicates the regional location of the Clarion—Clipperton Fracture Zone (CCZ) in the East Pacific Ocean, where the black line is the fracture zone, the white lines are the oceanic crust age isochron[14], and the red box represents the geographical location of the study area. The white dash line in fig.b indicates the boundary that separates study area into north and south parts. )

Tab.1

类别	SiO₂	Al₂O₃	CaO	TiO₂	FeO_t	MnO	MgO	Na₂O	K₂O	P₂O₅
最大值	80.01	16.53	6.47	0.88	9.28	6.16	6.29	13.23	3.91	2.62
最小值	52.21	5.30	1.06	0.20	2.54	0.10	2.08	3.56	1.07	0.26
平均值	60.36	14.78	1.92	0.75	7.62	0.91	3.92	6.16	2.99	0.60
标准差	2.55	1.22	0.78	0.09	0.59	0.54	0.39	0.94	0.30	0.51
变异系数	0.04	0.08	0.41	0.12	0.08	0.59	0.10	0.15	0.10	0.86
GLOSS	58.57	11.91	5.95	0.62	5.21	0.32	2.48	2.43	2.04	0.19
PAAS	65.89	15.17	4.19	0.50	4.49	0.07	2.20	3.89	2.80	0.20

Fig.2 Major element distribution pattern of sediments in the study area

Fig.3 REY distribution pattern of sediments in the study area (Data sources: bottom seawater of Southwest Pacific Ocean data are from reference [20], biogenic calcium apatite and calcium zeolite data are from referende [16], CCZ nodules data are from reference [21], Chinese loess data are from reference [22].)

Fig.4 Spatial distribution of major elements of sediments in the study area (The base map is a gray-scale topographic map.)

Fig.5 Spatial distribution of ∑REY and other related geochemical index of sediments in the study area (The base map is a gray-scale topographic map.)

Fig.6 Covariant relationship of ∑REY with P2O5 (a) and MnO (b)

Fig.7 Histogram of ∑REY content distribution in the western CCZ and cumulative frequency of ∑REY content in sediments from different regions of the Pacific Ocean

Fig.8 Comparison of ∑REY distribution patterns between the studied sediments and the Pacific REY-rich sediments

References 35

[1]	KATO Y, FUJINAGA K, NAKAMURA K, et al. Deep-sea mud in the Pacific Ocean as a potential resource for rare-earth elements[J]. Nature Geoscience, 2011, 4(8): 535-539. DOI
[2]	YASUKAWA K, KINO S, AZAMI K, et al. Geochemical features of Fe-Mn micronodules in deep-sea sediments of the western North Pacific Ocean: Potential for co-product metal extraction from REY-rich mud[J]. Ore Geology Reviews, 2020, 127: 103805. DOI URL
[3]	YASUKAWA K, LIU H J, FUJINAGA K, et al. Geochemistry and mineralogy of REY-rich mud in the eastern Indian Ocean[J]. Journal of Asian Earth Sciences, 2014, 93: 25-36. DOI URL
[4]	邓义楠, 任江波, 郭庆军, 等. 太平洋西部富稀土深海沉积物的地球化学特征及其指示意义[J]. 岩石学报, 2018, 34(3):733-747.
	DENG Y N, REN J B, GUO Q J, et al. Geochemistry characteristics of REY-rich sediment from deep sea in Western Pacific, and their indicative significance[J]. Acta Petrologica Sinica, 2018, 34(3): 733-747.
[5]	张霄宇, 黄牧, 石学法, 等. 中印度洋洋盆GC11岩心富稀土深海沉积的元素地球化学特征[J]. 海洋学报, 2019, 41(12):51-61.
	ZHANG X Y, HUANG M, SHI X F, et al. The geochemical characteristics of rare earth elements rich deep sea deposit of Core GC11 in central Indian Ocean Basin[J]. Haiyang Xuebao, 2019, 41(12): 51-61.
[6]	张霄宇, 石学法, 黄牧, 等. 深海富稀土沉积研究的若干问题[J]. 中国稀土学报, 2019, 37(5):517-529.
	ZHANG X Y, SHI X F, HUANG M, et al. Some problems in research of deep sea rare earth rich deposit[J]. Journal of the Chinese Society of Rare Earths, 2019, 37(5): 517-529.
[7]	ZHOU T C, SHI X F, HUANG M, et al. The influence of hydrothermal fluids on the REY-rich deep-sea sediments in the Yupanqui Basin, Eastern South Pacific Ocean: Constraints from bulk sediment geochemistry and mineralogical characteristics[J]. Minerals, 2020, 10(12): 1141. DOI URL
[8]	石学法, 符亚洲, 李兵, 等. 我国深海矿产研究:进展与发现(2011—2020)[J]. 矿物岩石地球化学通报,2021, 40(2):305-318.
	SHI X F, FU Y Z, LI B, et al. Research on deep-sea minerals in China:Progress and discovery (2011-2020)[J]. Bulletin of Mineralogy, Petrology and Geochemistry, 2021, 40(2): 305-318.
[9]	ZHANG H A, ZHOU J M, YUAN P, et al. Highly positive Ce anomalies of hydrogenetic ferromanganese micronodules from abyssal basins in the NW and NE Pacific: Implications for REY migration and enrichment in deep-sea sediments[J]. Ore Geology Reviews, 2023, 154: 105324. DOI URL
[10]	HEIN J R, KOSCHINSKY A, KUHN T. Deep-ocean polymetallic nodules as a resource for critical materials[J]. Nature Reviews Earth & Environment, 2020, 1(3): 158-169.
[11]	任江波, 姚会强, 朱克超, 等. 稀土元素及钇在东太平洋CC区深海泥中的富集特征与机制[J]. 地学前缘, 2015, 22(4):200-211. DOI
	REN J B, YAO H Q, ZHU K C, et al. Enrichment mechanism of rare earth elements and Yttrium in deep-sea mud of Clarion-Clipperton Region[J]. Earth Science Frontiers, 2015, 22(4): 200-211.
[12]	PAUL S A L, VOLZ J B, BAU M, et al. Calcium phosphate control of REY patterns of siliceous-ooze-rich deep-sea sediments from the central equatorial Pacific[J]. Geochimica et Cosmochimica Acta, 2019, 251: 56-72. DOI URL
[13]	KIM M G, HYEONG K, YOO C M. Distribution of rare earth elements and Yttrium in sediments from the Clarion-Clipperton fracture zone, Northeastern Pacific Ocean[J]. Geochemistry, Geophysics, Geosystems, 2022, 23(7): e2022GC010454.
[14]	MÜLLER R D, SETON M, ZAHIROVIC S, et al. Ocean basin evolution and global-scale plate reorganization events sincepangea breakup[J]. Annual Review of Earth and Planetary Sciences, 2016, 44: 107-138. DOI URL
[15]	STRAUME E O, GAINA C, MEDVEDEV S, et al. GlobSed: Updated total sediment thickness in the world’s oceans[J]. Geochemistry, Geophysics, Geosystems, 2019, 20(4): 1756-1772. DOI URL
[16]	TAKAYA Y, YASUKAWA K, KAWASAKI T, et al. The tremendous potential of deep-sea mud as a source of rare-earth elements[J]. Scientific Reports, 2018, 8: 5763. DOI PMID
[17]	王汾连, 何高文, 孙晓明, 等. 太平洋富稀土深海沉积物中稀土元素赋存载体研究[J]. 岩石学报, 2016, 32(7):2057-2068.
	WANG F L, HE G W, SUN X M, et al. The host of REE+Y elements in deep-sea sediments from the Pacific Ocean[J]. Acta Petrologica Sinica, 2016, 32(7): 2057-2068.
[18]	PLANK T, LANGMUIR C H. The chemical composition of subducting sediment and its consequences for the crust and mantle[J]. Chemical Geology, 1998, 145(3/4): 325-394. DOI URL
[19]	TAYLOR S R, MCLENNAN S M. The continental crust: Its composition and evolution[M]. Oxford: Blackwell Scientific Publica-tions, 1985: 1-312.
[20]	ZHANG J, NOZAKI Y. Rare earth elements and Yttrium in seawater: ICP-MS determinations in the East Caroline, Coral Sea, and South Fiji Basins of the western South Pacific Ocean[J]. Geochimica et Cosmochimica Acta, 1996, 60(23): 4631-4644. DOI URL
[21]	KUHN T, WEGORZEWSKI A, RÜHLEMANN C, et al. Composition, formation, and occurrence of polymetallic nodules[M]// Deep-Sea Mining. Cham: Springer Interna-tional Publishing, 2017: 23-63.
[22]	陈立业, 张珂, 傅建利, 等. 邙山黄土古土壤S₂沉积以来的微量和稀土元素地球化学特征及其物源指示意义[J]. 中山大学学报:自然科学版, 2018, 57(3):14-23.
	CHEN L Y, ZHANG K, FU J L, et al. The trace and rare earth element characteristics of Mangshan Loess since deposit of paleosol S₂ and its implications for provenance[J]. Acta Scientiarum Naturalium Universitatis Sunyatseni, 2018, 57(3): 14-23.
[23]	朱克超, 任江波, 王海峰, 等. 太平洋中部富REY深海粘土的地球化学特征及REY富集机制[J]. 地球科学, 2015, 40(6):1052-1060.
	ZHU K C, REN J B, WANG H F, et al. Enrichment mechanism of REY and geochemical characteristics of REY-rich pelagic clay from the central Pacific[J]. Earth Science, 2015, 40(6): 1052-1060.
[24]	任江波, 何高文, 朱克超, 等. 富稀土磷酸盐及其在深海成矿作用中的贡献[J]. 地质学报, 2017, 91(6):1312-1325.
	REN J B, HE G W, ZHU K C, et al. REY-rich phosphate and its effects on the deep-sea mud mineralization[J]. Acta Geologica Sinica, 2017, 91(6): 1312-1325.
[25]	LYLE M. Neogene carbonate burial in the Pacific Ocean[J]. Paleoceanography, 2003, 18(3): 1059.
[26]	KON Y, HOSHINO M, SANEMATSU K, et al. Geochemical characteristics of apatite in heavy REE-rich deep-sea mud from Minami-Torishima area, Southeastern Japan[J]. Resource Geology, 2014, 64(1): 47-57. DOI URL
[27]	LIAO J L, CHEN J Y, SUN X M, et al. Quantifying the controlling mineral phases of rare-earth elements in deep-sea pelagic sediments[J]. Chemical Geology, 2022, 595: 120792. DOI URL
[28]	LIAO J L, SUN X M, WU Z W, et al. Fe-Mn (oxyhydr)oxides as an indicator of REY enrichment in deep-sea sediments from the central North Pacific[J]. Ore Geology Reviews, 2019, 112: 103044. DOI URL
[29]	BI D J, SHI X F, HUANG M, et al. Geochemical and mineralogical characteristics of deep-sea sediments from the western North Pacific Ocean: Constraints on the enrichment processes of rare earth elements[J]. Ore Geology Reviews, 2021, 138: 104318. DOI URL
[30]	YU M, SHI X F, HUANG M, et al. The transfer of rare earth elements during early diagenesis in REY-rich sediments: An example from the Central Indian Ocean Basin[J]. Ore Geology Reviews, 2021, 136: 104269. DOI URL
[31]	TOYODA K, NAKAMURA Y, MASUDA A. Rare earth elements of Pacific pelagic sediments[J]. Geochimica et Cosmochimica Acta, 1990, 54(4): 1093-1103. DOI URL
[32]	REN J B, JIANG X X, HE G W, et al. Enrichment and sources of REY in phosphate fractions: Constraints from the leaching of REY-rich deep-sea sediments[J]. Geochimica et Cosmochimica Acta, 2022, 335: 155-168. DOI URL
[33]	GLASBY G P. Manganese: predominant role of nodules and crusts[M]//SCHULTZ H D, ZABEL M. Marine geochemistry. Berlin/Heidelberg: Springer-Verlag, 2006: 371-427.
[34]	JUAN C, VAN ROOIJ D, DE BRUYCKER W. An assessment of bottom current controlled sedimentation in Pacific Ocean abyssal environments[J]. Marine Geology, 2018, 403: 20-33. DOI URL
[35]	TANAKA E, NAKAMURA K, YASUKAWA K, et al. Chemostratigraphy of deep-sea sediments in the western North Pacific Ocean: Implications for genesis of mud highly enriched in rare-earth elements and Yttrium[J]. Ore Geology Reviews, 2020, 119: 103392. DOI URL