The role of marine sediment diagenesis in the modern oceanic magnesium cycle

The oceanic magnesium cycle is largely controlled by continental weathering and marine authigenic mineral formation, which are intimately linked to long-term climate. Uncertainties in the magnesium cycle propagate into other chemical budgets, and into interpretations of paleo-oceanographic reconstru...

Full description

Saved in:
Bibliographic Details
Published in:Nature communications Vol. 10; no. 1; pp. 4371 - 10
Main Authors: Berg, Richard D., Solomon, Evan A., Teng, Fang-Zhen
Format: Journal Article
Language:English
Published: London Nature Publishing Group UK 25.09.2019
Nature Publishing Group
Nature Portfolio
Subjects:
704/47/4112
704/829/827
Calcium
Chemical analysis
Diagenesis
Fluctuations
Flux
Fractionation
Humanities and Social Sciences
Isotope fractionation
Isotopes
Low temperature
Magnesium
Marine sediments
multidisciplinary
Ocean floor
Organic chemistry
Science
Science (multidisciplinary)
Seawater
Sediments
Water analysis
ISSN:2041-1723, 2041-1723
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The oceanic magnesium cycle is largely controlled by continental weathering and marine authigenic mineral formation, which are intimately linked to long-term climate. Uncertainties in the magnesium cycle propagate into other chemical budgets, and into interpretations of paleo-oceanographic reconstructions of seawater δ 26 Mg and Mg/Ca ratios. Here, we produce a detailed global map of the flux of dissolved magnesium from the ocean into deeper marine sediments (greater than ∼1 meter below seafloor), and quantify the global flux and associated isotopic fractionation. We find that this flux accounts for 15–20% of the output of magnesium from the ocean, with a flux-weighted fractionation factor of ∼0.9994 acting to increase the magnesium isotopic ratio in the ocean. Our analysis provides the best constraints to date on the sources and sinks that define the oceanic magnesium cycle, including new constraints on the output flux of magnesium and isotopic fractionation during low-temperature ridge flank hydrothermal circulation. The oceanic magnesium cycle is closely linked to Earth’s carbon cycle and long-term climate change, due to processes such as continental weathering and authigenic mineral formation. Here, the authors update the global oceanic magnesium budget by quantifying the flux of magnesium from oceans to marine sediments and the associated isotopic fractionation.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
content type line 23
ISSN:2041-1723
2041-1723
DOI:10.1038/s41467-019-12322-2