Abstract
AbstractRare earth element (REE)-rich phosphorite in the Guizhou region mainly exists in the Doushantuo Formation and Gezhongwu Formation in early Cambrian strata, which are some of the important strata containing phosphorite resources in China. The early Cambrian Zhijin phosphorite in Guizhou Province, China, has high rare earth element and yttrium (REY) contents of up to 2500 ppm, with heavy REY (HREY) contents accounting for ~ 30% of the total REY contents. However, the specific controlling source and environment of phosphorite (especially the REEs in Zhijin phosphorite) are still unsolved. Through field geological investigations; mineralogical, geochemical, Sr–Nd isotope analyses; and tectonic characteristics, the material source, sedimentary environment and seawater dynamics of REEs in phosphorite are studied. It is considered that the REEs enriched in the Zhijin phosphorite are mainly affected by precipitation from hydrothermal fluid. Moreover, from the late Ediacaran to the early Cambrian, the depositional environment from the bottom to the top of the water tended to be hypoxic, and the activity of hot water fluid tended to be strong. The change in redox conditions is closely related to the rise and fall of sea level. Combined with the tectonic background, these results show that the weakly oxidized environment may be an important factor controlling the enrichment of REEs. The enrichment of REEs may be closely related to volcanic hydrothermal activity, later diagenesis and seawater dynamics.
Funder
Zhejiang Provincial Natural Science Foundation of China
Zhejiang Provincial Education Department Foundation of China
Publisher
Springer Science and Business Media LLC
Reference55 articles.
1. Wu, S. X. et al. Recovery of rare earth elements from phosphorite rock by hydrometallurgical processes: A critical review. Chem. Eng. J. 335(1), 774–800 (2018).
2. Goodenough, K. M. The rare earth elements: Demand, global resources, and challenges for resourcing future generations. Nat. Resour. Res. 27(2), 201–216 (2018).
3. Chen, M. Z. et al. A prospective analysis on REE resources of the phosphorite-type REE ore deposits in China. Acta Mineral. Sin. 39(4), 345–358 (2019).
4. Emsbo, P., Mclaughlin, P. I. & Breit, G. N. Rare earth elements in sedimentary phosphorite deposits: Solution to the global REE crisis?. Gondwana Res. 27(2), 776–785 (2015).
5. Xie, H. & Zhu, L. J. Existing state and distribution regularity of rare earth elements from early Cambrian phosphorite in Guizhou. J. Chin. Soc. Rare Earths 30, 620–627 (2012).