The fertilization of the Bahamas by Saharan dust: A trigger for carbonate precipitation?

Peter K Swart, A. M. Oehlert, G. J. Mackenzie, Gregor P Eberli, J. J G Reijmer

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

The enigma of the Bahamas is that this highly productive carbonate system has existed for at least 100 m.y., building a vast edifice of carbonates, thousands of meters thick, in an essentially nutrientpoor environment. Based on measurements of the insoluble material, the Fe and Mn in the carbonate fraction, and the δ15N of the sedimentary organic matter, we suggest a paradigm shift in order to explain the formation of the Bahamas and possibly other similar platforms. We propose that the Great Bahama Bank is currently, and may in the past have been, fertilized by atmospheric dust, promoting the fixation of atmospheric N2 by cyanobacteria. These cyanobacteria provided a source of nitrogen to the rest of the community in this nutrient-poor environment. The fixation of N has imparted a characteristic δ15N signal and has been responsible, through the drawdown of CO2, for initiating the precipitation of carbonate in the shallow waters. This phenomenon might be responsible for the formation of vast amounts of sediments in the oceans, not only within recent times, but throughout geological history, particularly in the early history of the Earth prior to the existence of calcium carbonate- secretingorganisms.

Original languageEnglish (US)
Pages (from-to)671-674
Number of pages4
JournalGeology
Volume42
Issue number8
DOIs
StatePublished - 2014

Fingerprint

dust
carbonate
fixation
cyanobacterium
carbonate system
paradigm shift
history
drawdown
calcium carbonate
shallow water
organic matter
nutrient
nitrogen
ocean
sediment
material

ASJC Scopus subject areas

  • Geology

Cite this

The fertilization of the Bahamas by Saharan dust : A trigger for carbonate precipitation? / Swart, Peter K; Oehlert, A. M.; Mackenzie, G. J.; Eberli, Gregor P; Reijmer, J. J G.

In: Geology, Vol. 42, No. 8, 2014, p. 671-674.

Research output: Contribution to journalArticle

Swart, Peter K ; Oehlert, A. M. ; Mackenzie, G. J. ; Eberli, Gregor P ; Reijmer, J. J G. / The fertilization of the Bahamas by Saharan dust : A trigger for carbonate precipitation?. In: Geology. 2014 ; Vol. 42, No. 8. pp. 671-674.
@article{06d81f40d0304d16adb6bd9d6ca02caf,
title = "The fertilization of the Bahamas by Saharan dust: A trigger for carbonate precipitation?",
abstract = "The enigma of the Bahamas is that this highly productive carbonate system has existed for at least 100 m.y., building a vast edifice of carbonates, thousands of meters thick, in an essentially nutrientpoor environment. Based on measurements of the insoluble material, the Fe and Mn in the carbonate fraction, and the δ15N of the sedimentary organic matter, we suggest a paradigm shift in order to explain the formation of the Bahamas and possibly other similar platforms. We propose that the Great Bahama Bank is currently, and may in the past have been, fertilized by atmospheric dust, promoting the fixation of atmospheric N2 by cyanobacteria. These cyanobacteria provided a source of nitrogen to the rest of the community in this nutrient-poor environment. The fixation of N has imparted a characteristic δ15N signal and has been responsible, through the drawdown of CO2, for initiating the precipitation of carbonate in the shallow waters. This phenomenon might be responsible for the formation of vast amounts of sediments in the oceans, not only within recent times, but throughout geological history, particularly in the early history of the Earth prior to the existence of calcium carbonate- secretingorganisms.",
author = "Swart, {Peter K} and Oehlert, {A. M.} and Mackenzie, {G. J.} and Eberli, {Gregor P} and Reijmer, {J. J G}",
year = "2014",
doi = "10.1130/G35744.1",
language = "English (US)",
volume = "42",
pages = "671--674",
journal = "Geology",
issn = "0091-7613",
publisher = "Geological Society of America",
number = "8",

}

TY - JOUR

T1 - The fertilization of the Bahamas by Saharan dust

T2 - A trigger for carbonate precipitation?

AU - Swart, Peter K

AU - Oehlert, A. M.

AU - Mackenzie, G. J.

AU - Eberli, Gregor P

AU - Reijmer, J. J G

PY - 2014

Y1 - 2014

N2 - The enigma of the Bahamas is that this highly productive carbonate system has existed for at least 100 m.y., building a vast edifice of carbonates, thousands of meters thick, in an essentially nutrientpoor environment. Based on measurements of the insoluble material, the Fe and Mn in the carbonate fraction, and the δ15N of the sedimentary organic matter, we suggest a paradigm shift in order to explain the formation of the Bahamas and possibly other similar platforms. We propose that the Great Bahama Bank is currently, and may in the past have been, fertilized by atmospheric dust, promoting the fixation of atmospheric N2 by cyanobacteria. These cyanobacteria provided a source of nitrogen to the rest of the community in this nutrient-poor environment. The fixation of N has imparted a characteristic δ15N signal and has been responsible, through the drawdown of CO2, for initiating the precipitation of carbonate in the shallow waters. This phenomenon might be responsible for the formation of vast amounts of sediments in the oceans, not only within recent times, but throughout geological history, particularly in the early history of the Earth prior to the existence of calcium carbonate- secretingorganisms.

AB - The enigma of the Bahamas is that this highly productive carbonate system has existed for at least 100 m.y., building a vast edifice of carbonates, thousands of meters thick, in an essentially nutrientpoor environment. Based on measurements of the insoluble material, the Fe and Mn in the carbonate fraction, and the δ15N of the sedimentary organic matter, we suggest a paradigm shift in order to explain the formation of the Bahamas and possibly other similar platforms. We propose that the Great Bahama Bank is currently, and may in the past have been, fertilized by atmospheric dust, promoting the fixation of atmospheric N2 by cyanobacteria. These cyanobacteria provided a source of nitrogen to the rest of the community in this nutrient-poor environment. The fixation of N has imparted a characteristic δ15N signal and has been responsible, through the drawdown of CO2, for initiating the precipitation of carbonate in the shallow waters. This phenomenon might be responsible for the formation of vast amounts of sediments in the oceans, not only within recent times, but throughout geological history, particularly in the early history of the Earth prior to the existence of calcium carbonate- secretingorganisms.

UR - http://www.scopus.com/inward/record.url?scp=84905170126&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84905170126&partnerID=8YFLogxK

U2 - 10.1130/G35744.1

DO - 10.1130/G35744.1

M3 - Article

AN - SCOPUS:84905170126

VL - 42

SP - 671

EP - 674

JO - Geology

JF - Geology

SN - 0091-7613

IS - 8

ER -