Early diagenetic REE migration from Fe-Mn nodules to fish teeth in deep sea sediments

• DOI: 10.1016/j.oregeorev.2023.105581
• Publication Date: 2023-07-22T23:19:49Z
• Authors: Fei Huang; Yu Fu; Dengfeng Li; Jinzhou Peng; Wentao He; Saiyu Li; Xiaoming Sun; Gaowen He
• Keywords: Ferromanganese; Nodule (geology); Rare-earth element

In deep sea sediments, rare earth elements and yttrium (REYs) are predominantly carried by bioapatite Fe-Mn (oxyhydr)oxides. According to recent studies, REYs can migrate into after the dissolution of However, REY migration mechanism from (oxyhydr)oxides still unclear. Here, we integrated in situ trace element Nd isotope analyses elucidate geochemical characteristics fish tooth-bearing nodules Northwest Pacific Ocean. Our nodule samples be classified different morphological types periods early diagenesis: (I) completely overgrown around bioapatite; II) half bioapatite. Type I grow a core, which has high LaN/SmN (0.41–0.50, avg. 0.46) LaN/YbN (0.49–0.90, 0.62). The ΣREY content is non-uniform two (WP-01 & WP-02) nodules, i.e., 475–2150 ppm 272–431 ppm, respectively. results show that mainly adsorbed diagenesis. II were covered both inside at tip tooth. (0.34–0.38, 0.36) (0.26–0.61, 0.37) ratios relatively low. Meanwhile, very uneven (229–3521 ppm). data substituted during strong intercrystalline pores some authigenic apatite may have closed upon recrystallization, causing redistribution fractionation. Y/Ho vs. ΣREE/Th plot shows higher proportion pore water type than ones. widespread distribution Mn gradual decrease rim core reflect transport dissolved diagenesis under suboxic conditions. From mean εNd value increases -6.69 -5.56. comparison εNd(0) values between REY-rich mud indicate derived bottom sediments. findings comprehensively document enrichment mechanisms diagenetic processes bioapatite, argued localized.