Rotation of a Ferromanganese Nodule in the Penrhyn Basin, South Pacific, Tracked by the Earth's Magnetic Field

Abstract

Marine ferromanganese nodules (nodules, hereafter) are widely found abyssal concretions with concentric layers of manganese-iron-hydroxides, which typically grow at a speed of about few mm/Myr (e.g., Verlaan & Cronan, 2022;von Stackelberg, 2000). These nodules are considered as a future mineral resource of Cu, Ni, Co, and rare earth elements. While such nodules are also found buried in deeper sediments, many of them are still exposed on the sediment surface despite their geologically old age of tens of millions of years (e.g., Verlaan & Cronan, 2022;von Stackelberg, 2000). The nodules are composed of two phases: diagenetic buserite with metal ions in sediment and hydrogenetic vernadite with colloids in seawater (e.g., Skowronek et al., 2021;Usui & Someya, 1997;Usui et al., 1989;Verlaan & Cronan, 2022). Usui and Ito (1994) demonstrated using Ocean Drilling Program cores that buried nodules are usually found in stratigraphic layers corresponding to hiatuses or slow sedimentations. Graham et al. ( 2004) reported using 10 Be chronology that the surface ages of the buried nodules

Morphology‐Dependent Magnetic Properties in Shallow‐Water Ferromanganese Concretions

“…Assuming that these parameters reflect the total ferrimagnetic mineral concentration, the abundance of these minerals in Baltic Sea concretions is similar or slightly greater than in some deep Pacific Ocean hydrogenetic nodules (cf. Jiang et al., 2020, 2022; Oda et al., 2023), but the single‐domain (SD) magnetite content is slightly lower as indicated by lower χARM (Table 2). This discrepancy could result from the slower growth of deep ocean Fe‐Mn precipitates and an increased terrigenous influence on Baltic Sea concretions, which is attributed to their contrasting marine settings.…”

“…Recent discoveries have shown that biogenic magnetite contributes to a biogeochemical remanent magnetization in deep ocean crusts and nodules (Hassan et al., 2020; Jiang et al., 2020; Oda et al., 2018; Yuan et al., 2020), which indicates the impact of abyssal microbial communities on nodule biomineralization. While extensive studies on the magnetic properties and magnetostratigraphic dating of deep ocean concretions have been carried out (e.g., Jiang et al., 2021; Joshima & Usui, 1998; Oda et al., 2023), no such investigations have been undertaken on fast‐growing shallow water concretions in shelf seas such as the Baltic Sea. Furthermore, the specific mechanisms of concretion formation and (bio)mineralization for different Baltic Sea morphotypes remain poorly understood.…”

Identification Morphology and Magnetic Properties Sedimentary Elements Between Fossils and Outcrops Around the Lusi River: A Case Study of Central Java, Indonesia

“…These recordings provide information about the nature of the past. Much can be learned in the field of paleomagnetism one of them is mineralogy [29][30][31].…”