Development of Iron Speciation Reference Materials for Palaeoredox Analysis
Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Standard
Development of Iron Speciation Reference Materials for Palaeoredox Analysis. / Alcott, Lewis J.; Krause, Alexander J.; Hammarlund, Emma U.; Bjerrum, Christian J.; Scholz, Florian; Xiong, Yijun; Hobson, Andrew J.; Neve, Lesley; Mills, Benjamin J. W.; Marz, Christian; Schnetger, Bernhard; Bekker, Andrey; Poulton, Simon W.
I: Geostandards and Geoanalytical Research, Bind 44, Nr. 3, 2020, s. 581-591.Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Development of Iron Speciation Reference Materials for Palaeoredox Analysis
AU - Alcott, Lewis J.
AU - Krause, Alexander J.
AU - Hammarlund, Emma U.
AU - Bjerrum, Christian J.
AU - Scholz, Florian
AU - Xiong, Yijun
AU - Hobson, Andrew J.
AU - Neve, Lesley
AU - Mills, Benjamin J. W.
AU - Marz, Christian
AU - Schnetger, Bernhard
AU - Bekker, Andrey
AU - Poulton, Simon W.
PY - 2020
Y1 - 2020
N2 - The development and application of geochemical techniques to identify redox conditions in modern and ancient aquatic environments has intensified over recent years. Iron (Fe) speciation has emerged as one of the most widely used procedures to distinguish different redox regimes in both the water column and sediments, and is the main technique used to identify oxic, ferruginous (anoxic, Fe(II) containing) and euxinic (anoxic, sulfidic) water column conditions. However, an international sediment reference material has never been developed. This has led to concern over the consistency of results published by the many laboratories that now utilise the technique. Here, we report an interlaboratory comparison of four Fe speciation reference materials for palaeoredox analysis, which span a range of compositions and reflect deposition under different redox conditions. We provide an update of extraction techniques used in Fe speciation and assess the effects of both test portion mass, and the use of different analytical procedures, on the quantification of different Fe fractions in sedimentary rocks. While atomic absorption spectroscopy and inductively coupled plasma-optical emission spectrometry produced comparable Fe measurements for all extraction stages, the use of ferrozine consistently underestimated Fe in the extraction step targeting mixed ferrous-ferric minerals such as magnetite. We therefore suggest that the use of ferrozine is discontinued for this Fe pool. Finally, we report the combined data of four independent Fe speciation laboratories to characterise the Fe speciation composition of the reference materials. These reference materials are available to the community to provide an essential validation of in-house Fe speciation measurements.
AB - The development and application of geochemical techniques to identify redox conditions in modern and ancient aquatic environments has intensified over recent years. Iron (Fe) speciation has emerged as one of the most widely used procedures to distinguish different redox regimes in both the water column and sediments, and is the main technique used to identify oxic, ferruginous (anoxic, Fe(II) containing) and euxinic (anoxic, sulfidic) water column conditions. However, an international sediment reference material has never been developed. This has led to concern over the consistency of results published by the many laboratories that now utilise the technique. Here, we report an interlaboratory comparison of four Fe speciation reference materials for palaeoredox analysis, which span a range of compositions and reflect deposition under different redox conditions. We provide an update of extraction techniques used in Fe speciation and assess the effects of both test portion mass, and the use of different analytical procedures, on the quantification of different Fe fractions in sedimentary rocks. While atomic absorption spectroscopy and inductively coupled plasma-optical emission spectrometry produced comparable Fe measurements for all extraction stages, the use of ferrozine consistently underestimated Fe in the extraction step targeting mixed ferrous-ferric minerals such as magnetite. We therefore suggest that the use of ferrozine is discontinued for this Fe pool. Finally, we report the combined data of four independent Fe speciation laboratories to characterise the Fe speciation composition of the reference materials. These reference materials are available to the community to provide an essential validation of in-house Fe speciation measurements.
KW - iron speciation
KW - sequential extraction
KW - reference materials
KW - water column redox
KW - total iron
KW - ancient sediments
KW - SOUTHERN KAROO BASIN
KW - PALEOREDOX PROXIES
KW - REACTIVE IRON
KW - ANOXIA
KW - INDICATOR
KW - OCEAN
KW - SEDIMENTS
KW - MINERALS
KW - SULFIDE
U2 - 10.1111/ggr.12342
DO - 10.1111/ggr.12342
M3 - Journal article
VL - 44
SP - 581
EP - 591
JO - Geostandards and Geoanalytical Research
JF - Geostandards and Geoanalytical Research
SN - 1639-4488
IS - 3
ER -
ID: 244998563