2021年1月2日 · Pelagic sediments are defined as those formed of settled material that has fallen through the water column; their distribution is controlled by three main factors, distance from major landmasses (which affects their dilution by terrigenous, or land-derived, material), water depth (which affects sediment preservation), and ocean fertility (which controls surface water …

2022年4月20日 · The REE-enriched pelagic sediment was suggested to be a significant reservoir for the global REE budget (Chen et al., 2015; Plank and Langmuir, 1998). Since the first report was published indicating that pelagic sediments have the potential to become REE resources in the future, this topic has received global attention ( Kato et al., 2011 ).

2023年10月1日 · In this study, a refined chronostratigraphic framework for a sediment core (core C) collected from the northwestern Pacific Ocean pelagic environment, was established by combining authigenic 10 Be/ 9 Be dating, 230 Th ex dating, and magnetostratigraphy. The obtained results indicate that integration of multi-geochronologic approaches seems ...

2024年12月1日 · Other sediment types considered in the model are typical pelagic sediments, namely clay, calcareous ooze, and siliceous ooze. However, a certain kind of pelagic clay, often categorized as zeolitic clay, is distinguished from ordinary clay based on its REE concentration (i.e., REE-rich mud).

The contribution of chemical species from the different geospheres is considered. The quantitative importance of pelagic clays in the major sedimentary cycle is studied on the basis of the distribution of the weathered igneous rock products between continental and …

2002年7月1日 · Pelagic sediments are the result of various processes including detrital supply from continental areas, pyroclastic deposition, hydrothermal activity, authigenic precipitation, biological activity, and diagenesis (Chester, 1990, and references therein).

2024年7月1日 · As mentioned above, the Sc contents in ferromanganese micronodules of pelagic sediments are ∼2–20 ppm, which is lower than that of pelagic clay. The Sc concentration is also relatively low in polymetallic nodules and ferromanganese crusts (commonly <20 ppm), and only those of the Arctic crusts could have an average value of 46.9 ppm ( Hein ...

2007年2月28日 · The 70 m thick sediment section consists of three units: a 26 m of pelagic red clay unit with prominent zeolites intervals (mostly between ∼ 6 to 10 mbsf, and less abundant but continuous throughout to 26 mbsf) overlying 42 m of clayey nannofossil ooze unit (Fig. 2). There is also a 2 m thick basal unit below 60 mbsf that is composed of ...

2021年11月1日 · The bulk sediment XRD analyses and microscopic observations show that bioapatite fossil is the main Ca-bearing mineral in the pelagic clay sediments where carbonate is absent, whereas carbonate is the main Ca-bearing mineral in …

1990年4月1日 · The chemical compositions of 140 deep-sea sediment samples collected in the Pacific were examined. The characteristic features of the abundances of REEs in the sediment samples, including pelagic red clay, calcareous ooze, and blue mud, are demonstrated especially by a variety of Ce anomalies in the shale-normalized REE pattern.