DOI: 10.1111/gbi.12139
Scopus记录号: 2-s2.0-84930762220
论文题名: In situ trace metal analysis of Neoarchaean - Ordovician shallow-marine microbial-carbonate-hosted pyrites
作者: Gallagher M. ; Turner E.C. ; Kamber B.S.
刊名: Geobiology
ISSN: 1472-4677
EISSN: 1472-4669
出版年: 2015
卷: 13, 期: 4 起始页码: 316
结束页码: 339
语种: 英语
Scopus关键词: abundance
; Archean
; carbonate
; concentration (composition)
; hydrothermal system
; in situ measurement
; inventory
; marine sediment
; microbial activity
; morphology
; Ordovician
; paleoceanography
; petrography
; Precambrian-Cambrian boundary
; pyrite
; redox conditions
; sedimentary rock
; shallow water
; trace metal
; carbonic acid derivative
; iron
; metal
; pyrite
; sea water
; sulfide
; archaeon
; astronomy
; bacterium
; chemistry
; fossil
; metabolism
; microbiology
; sediment
; Archaea
; Bacteria
; Carbonates
; Earth (Planet)
; Evolution, Planetary
; Fossils
; Geologic Sediments
; Iron
; Metals
; Seawater
; Sulfides
Scopus学科分类: Earth and Planetary Sciences: General Earth and Planetary Sciences
; Environmental Science: General Environmental Science
; Agricultural and Biological Sciences: Ecology, Evolution, Behavior and Systematic
英文摘要: Pre-Cambrian atmospheric and oceanic redox evolutions are expressed in the inventory of redox-sensitive trace metals in marine sedimentary rocks. Most of the currently available information was derived from deep-water sedimentary rocks (black shale/banded iron formation). Many of the studied trace metals (e.g. Mo, U, Ni and Co) are sensitive to the composition of the exposed land surface and prevailing weathering style, and their oceanic inventory ultimately depends on the terrestrial flux. The validity of claims for increased/decreased terrestrial fluxes has remained untested as far as the shallow-marine environment is concerned. Here, the first systematic study of trace metal inventories of the shallow-marine environment by analysis of microbial carbonate-hosted pyrite, from ca. 2.65-0.52 Ga, is presented. A petrographic survey revealed a first-order difference in preservation of early diagenetic pyrite. Microbial carbonates formed before the 2.4 Ga great oxygenation event (GOE) are much richer in pyrite and contain pyrite grains of greater morphological variability but lesser chemical substitution than samples deposited after the GOE. This disparity in pyrite abundance and morphology is mirrored by the qualitative degree of preservation of organic matter (largely as kerogen). Thus, it seems that in microbial carbonates, pyrite formation and preservation were related to presence and preservation of organic C. Several redox-sensitive trace metals show interpretable temporal trends supporting earlier proposals derived from deep-water sedimentary rocks. Most notably, the shallow-water pyrite confirms a rise in the oceanic Mo inventory across the pre-Cambrian-Cambrian boundary, implying the establishment of efficient deep-ocean ventilation. The carbonate-hosted pyrite also confirms the Neoarchaean and early Palaeoproterozoic ocean had higher Ni concentration, which can now more firmly be attributed to a greater proportion of magnesian volcanic rock on land rather than a stronger hydrothermal flux of Ni. Additionally, systematic trends are reported for Co, As, and Zn, relating to terrestrial flux and oceanic productivity. © 2015 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/85146
Appears in Collections: 影响、适应和脆弱性
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作者单位: Department of Geology, Trinity College Dublin, Dublin, Ireland; Department of Earth Sciences, Laurentian University, Sudbury, ON, Canada
Recommended Citation:
Gallagher M.,Turner E.C.,Kamber B.S.. In situ trace metal analysis of Neoarchaean - Ordovician shallow-marine microbial-carbonate-hosted pyrites[J]. Geobiology,2015-01-01,13(4)