Not logged in
PANGAEA.
Data Publisher for Earth & Environmental Science

Bollhöfer, A; Frank, Norbert; Rohloff, S; Mangini, Augusto; Scholten, Jan Christoph (1999): Description of, and 238U, 234U, 232Th and 230Th measurements on a nodule from R/V Sonne station SO79_62KD, Central East Pacific Ocean [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.855889, Supplement to: Bollhöfer, A et al. (1999): A record of changing redox conditions in the northern Peru Basin during the Late Quaternary deduced from Mn/Fe and growth rate variations in two diagenetic manganese nodules. Earth and Planetary Science Letters, 170(4), 403-415, https://doi.org/10.1016/S0012-821X(99)00126-0

Always quote citation above when using data! You can download the citation in several formats below.

RIS CitationBibTeX CitationShow MapGoogle Earth

Abstract:
Two diagenetic manganese nodules from the Peru Basin were investigated by thermal ionization mass spectrometry and high resolution alpha spectrometry for uranium and thorium. The TIMS concentrations for nodule 62KD (63KG) vary as follows: 0.12-1.01 ppb (0.06-0.59) 230Th, 0.51-1.98 ppm (0.43-1.40) 232Th, 0.13-0.80 ppb (0.09-0.49) 234U, and 1.95-13.47 ppm (1.66-8.24) 238U. Both nodules have average growth rates of ~110 mm per million years. However, from the variations of excess 230Th with depth we estimate partial accumulation rates which range from 50 to 400 mm per million years. The 234U dating method cannot be applied due to remobilization of U from the sediment and subsequent incorporation into the nodules' crystal lattice, reflected by decay corrected 234U values far above the ocean water value. Sections of fast nodule growth are related to those layers having high Mn/Fe ratios (up to 200) and higher densities. As a possible explanation we develop a scenario that describes similar glacial/interglacial trends in both nodules as a record of regional changes of sediment and/or deep water chemistry.
Source:
Grant, John Bruce; Moore, Carla J; Alameddin, George; Chen, Kuiying; Barton, Mark (1992): The NOAA and MMS Marine Minerals Geochemical Database. National Geophysical Data Center, NOAA, https://doi.org/10.7289/V52Z13FT
Further details:
Warnken, Robin R; Virden, William T; Moore, Carla J (1992): The NOAA and MMS Marine Minerals Bibliography. National Geophysical Data Center, NOAA, https://doi.org/10.7289/V53X84KN
Coverage:
Latitude: -6.718300 * Longitude: -90.568300
Date/Time Start: 1992-05-06T00:00:00 * Date/Time End: 1992-05-06T00:00:00
Event(s):
SO79_62KD * Latitude: -6.718300 * Longitude: -90.568300 * Date/Time: 1992-05-06T00:00:00 * Elevation: -4341.0 m * Location: Peru Basin * Campaign: SO79 (SEDIPERU - TUSCH) * Basis: Sonne * Method/Device: Dredge, box (DRG_B) * Comment: GPS, Mn nodules
Comment:
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.
Size:
3 datasets

Download Data

Download ZIP file containing all datasets as tab-delimited text — use the following character encoding: