DOI: 10.1111/gbi.12183
Scopus记录号: 2-s2.0-85028256374
论文题名: Enhanced procedural blank control for organic geochemical studies of critical sample material
作者: Leider A. ; Schumacher T.C. ; Hallmann C.
刊名: Geobiology
ISSN: 1472-4677
EISSN: 1472-4669
出版年: 2016
卷: 14, 期: 5 起始页码: 469
结束页码: 482
语种: 英语
Scopus关键词: hydrocarbon
; adsorption
; artifact
; biomarker
; bitumen
; black shale
; hydrocarbon
; laboratory method
; lithology
; organic carbon
; plastic
; Precambrian
; sampling
; sediment pollution
; surface area
; chemical analysis
; chemistry
; sediment
; standards
; Chemistry Techniques, Analytical
; Geologic Sediments
; Hydrocarbons
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: Organic contamination of sedimentary rocks can produce artefacts in studies of hydrocarbon composition, and this can have significant negative consequences for interpretations of the geobiological record. False positives - that is cases of non-syngenetic hydrocarbon biomarkers - are common in Precambrian studies, and significant challenges persist despite the intensive effort devoted to these studies. Efforts to standardize the 'burden of proof' for distinguishing between contamination and syngenetic material have to date failed to yield a simple or universal protocol, yet the need remains great, as both bitumen-lean rocks and bitumen-rich samples can be vulnerable to the accumulation of false-positive signals. In an effort to determine the best approach to quality control, we tested the capability of different blank materials to collect ambient contamination by assessing their capacity to adsorb hydrocarbons during storage in plastic bags and found that commonly used Quartz sand does not provide an adequate measure of storage- or laboratory-induced contamination. Brick blanks, having the advantage that they can parallel rock samples even during the sawing process, are characterized by similar poor adsorption properties. Primarily steered by mineralogy, organic carbon content and surface area, model-black shales can adsorb up to 20 times more contaminants than sand blanks and up to 200 times more contaminants than organic-free model-carbonates. This observation provides an explanation for reports and observations of seemingly systematic stratigraphic variation of contaminants, but mostly should raise awareness for the evaluation of procedural blanks, in particular of sample-to-blank ratios, when studying bitumen-lean rock samples of varying lithologies. Additionally, differences between the hydrocarbon profiles in plastic bags and the hydrocarbon signatures transferred to blank materials emphasize difficulties in the unequivocal detection of contamination sources. Artificial black shale pellets can provide enhanced contamination control in biomarker studies - particularly for exceptionally vulnerable samples such as Precambrian rocks, meteorites or extraterrestrial sample-return material. © 2016 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/85094
Appears in Collections: 影响、适应和脆弱性
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作者单位: Max-Planck-Institute for Biogeochemistry, Jena, Germany; Advanced Ceramics Group, Department of Production Engineering, University of Bremen, Bremen, Germany; MARUM, Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Recommended Citation:
Leider A.,Schumacher T.C.,Hallmann C.. Enhanced procedural blank control for organic geochemical studies of critical sample material[J]. Geobiology,2016-01-01,14(5)