Archive · collection · 1994
Beryllium, thorium and protactinium isotope ratios in sediments from the Galapagos microplate
Listed in PANGAEA and DataCite — shown once because both records carry DOI 10.1594/pangaea.726083
Biogenic particle fluxes from highly productive surface waters, boundary scavenging, and hydrothermal activity are the main factors influencing the deposition of radionuclides in the area of the Galapagos microplate, eastern Equatorial Pacific.
Description
In order to evaluate the importance of these three processes throughout the last 100 kyr, concentrations of the radionuclides 10Be, 230Th, and 231Pa, and of Mn and Fe were measured at high resolution in sediment samples from two gravity cores KLH 068 and KLH 093.
High biological productivity in the surface waters overlying the investigated area has led to 10Be and 231Pa fluxes exceeding production during at least the last 30 kyr and probably the last 100 kyr. However, during periods of high productivity at the up welling centers off Peru and extension of the equatorial high-productivity zone, a relative loss of 10Be and 231Pa may have occurred in these sediment cores because of boundary scavenging.
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The effects of hydrothermal activity were investigated by comparing the 230Thex concentrations to the Mn/Fe ratios and by comparing the fluxes of 230Th and 10Be which exceed production. The results suggest an enhanced hydrothermal influence during isotope stages 4 and 5 and to a lesser extent during isotope stage 1 in core KLH 093. During isotope stages 2 and 3, the hydrothermal supply of Mn was deposited elsewhere, probably because of changes in current regime or deep water oxygenation.
A strong increase of the Mn/Fe ratio at the beginning of climatic stage 1 which is not accompanied by an increase of the 230Thex concentration is interpreted to be an effect of Mn remobilization and reprecipitation in the sediment.
Links
Where it is published
- Repository landing page doi.pangaea.de/10.1594/PANGAEA.726083 ↗
landing page · from DataCite
- DOI doi.org/10.1594/pangaea.726083 ↗
DOI / persistent id · from PANGAEA
Documentation and papers
- Creative Commons Attribution 3.0 Unported creativecommons.org/licenses/by/3.0/legalcode ↗
license · from DataCite
- IsSupplementTo 10.1029/94pa01132 doi.org/10.1029/94pa01132 ↗
publication · from DataCite
Catalogue records · 3
- OAI-PMH record ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=oai_dc&identifier=o… ↗
metadata API · from PANGAEA
- DataCite API api.datacite.org/dois/10.1594/pangaea.726083 ↗
metadata API · from DataCite
- DataCite Commons commons.datacite.org/doi.org/10.1594/pangaea.726083 ↗
catalogue entry · from DataCite
Topics
- From keywords
- Earth & Environmental Science
- Inferred from text
- Geochemistry 72%
Provenance · 2 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| PANGAEA | oai:pangaea.de:doi:10.1594/PANGAEA.726083 | 14 d ago | JSON v1 |
| DataCite | 10.1594/pangaea.726083 | 14 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · PANGAEA | connector:pangaea@1.0.0 | |
| concepts[field].anzsrc:group:3703 | enrichment · DataCite | taxonomy-embedding@1.1.0 | title+keywords+description (72%) |
| concepts[field].local:field:earth-environmental | mapping · PANGAEA | connector:pangaea@1.0.0 | |
| description | source · PANGAEA | connector:pangaea@1.0.0 | /metadata/dc/description |
| license | source · PANGAEA | connector:pangaea@1.0.0 | /metadata/dc/rights |
| publication_date | source · PANGAEA | connector:pangaea@1.0.0 | |
| spatial | source · PANGAEA | connector:pangaea@1.0.0 | |
| title | source · PANGAEA | connector:pangaea@1.0.0 | /metadata/dc/title |