Publication Date:
2008-07-19
Description:
Earth's surface chemical environment has evolved from an early anoxic condition to the oxic state we have today. Transitional between an earlier Proterozoic world with widespread deep-water anoxia and a Phanerozoic world with large oxygen-utilizing animals, the Neoproterozoic Era [1000 to 542 million years ago (Ma)] plays a key role in this history. The details of Neoproterozoic Earth surface oxygenation, however, remain unclear. We report that through much of the later Neoproterozoic (〈742 +/- 6 Ma), anoxia remained widespread beneath the mixed layer of the oceans; deeper water masses were sometimes sulfidic but were mainly Fe2+-enriched. These ferruginous conditions marked a return to ocean chemistry not seen for more than one billion years of Earth history.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Canfield, Donald E -- Poulton, Simon W -- Knoll, Andrew H -- Narbonne, Guy M -- Ross, Gerry -- Goldberg, Tatiana -- Strauss, Harald -- New York, N.Y. -- Science. 2008 Aug 15;321(5891):949-52. doi: 10.1126/science.1154499. Epub 2008 Jul 17.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Nordic Center for Earth Evolution and Institute of Biology, Campusvej 55, University of Southern Denmark, 5230 Odense, Denmark. dec@biology.sdu.dk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18635761" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Atmosphere
;
Geologic Sediments/*chemistry
;
Ice Cover
;
Iron/*analysis
;
Oceans and Seas
;
Oxidation-Reduction
;
Oxygen/*analysis
;
Seawater/*chemistry
;
Sulfates/analysis
;
Sulfides/analysis
;
Time
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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