Five ferromanganese crusts and 6 ferromanganese nodules samples collected by the Joint Chinese-West Germany Geophysical Investigation Team in May—June, 1987 during the SO49 cruise of the R/V Sonne. They were analyzed for their rare earth element contents by means of X-Ray fluorescent spectrometry. On the basis of study of 15 rare earth elements detected, the relationship among rare earth element concentration, source,, as well as distribution pattern and associated elements was discussed in detail. Results show that 1) The average concentration of rare earth elements in South China Sea ferromanganese crusts and nodules was 1. 625 g/kg and 2. 167 g/kg respectively. This concentration is 1—2 times higher than that in Pacific ferromanganese nodules, 5—6 times higher than that found in North Pacific sediments, and 10—20 times higher than that found in South China Sea sediments. 2) Distribution pattern of rare earth elements in ferromanganese nodules and crusts are basically the same. Ce is positively abnormal and Eu deficit is not obvious. Results of comparative study of associated elements, sediments, and rare earth elements of rocks show that rare earth elements in ferromanganese nodules and crusts were deposited mainly in South China Sea medium-acidic rocks after they had undergone weathering and wetting.
From 1983 until 1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions. At the time it was the most extended data compilation on ferromanganese deposits world wide. Initially published in a proprietary format incompatible with present day standards it was jointly decided by AWI and NOAA to transcribe this legacy data into PANGAEA. This transfer is augmented by a careful checking of the original sources when available and the encoding of ancillary information (sample description, method of analysis...) not present in the NOAA-MMS database.
Supplement to: Bao, G; Li, Q (1993): Geochemistry of rare earth elements of ferromanganese nodules (crusts) from the South China (in Chinese). Oceanologia et Limnologia Sinica, 24(3), 304-313
