Title | The iBox-FC: a new containment vessel for Itrax X-ray fluorescence core-scanning of freeze cores |
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Author | Gregory, B R B; Patterson, R T; Reinhardt, E; Galloway, J M |
Source | Quaternary International vol. 514, 2018 p. 79-84, https://doi.org/10.1016/j.quaint.2018.09.008 |
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Year | 2018 |
Alt Series | Natural Resources Canada, Contribution Series 20180085 |
Publisher | Elsevier |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Subjects | Nature and Environment; paleontology; Science and Technology; geochemistry; cores; x-ray fluorescence; paleoclimatology; paleoenvironment; lacustrine environments; anthropogenic deposits; Scientific
equipment |
Illustrations | cross-sections; photographs; location maps; figures; schematic diagrams; graphs; tables; geochemical plots; plots |
Program | Environmental
Geoscience Metal Mining: northern baselines |
Released | 2018 09 11 |
Abstract | A combination of Itrax micro-X-ray fluorescence core scanning (uXRF-CS) and freeze coring can facilitate the development of high-resolution (e.g. sub-decadal) paleoclimate records in lacustrine systems
where low sedimentation rates and poorly consolidated "colloidal soup" at the sediment/water interface prevents retrieval and Itrax-uXRF-CS analysis of undisturbed cores using conventional gravity corers. The iBox-FC containment vessel described and
tested here delays thawing of highly perishable freeze cores for up to two hours, providing adequate time to carry out high-resolution Itrax-uXRF-CS analysis. The iBox-FC is comprised of an open-topped Styrofoam box divided into chambers using
high-density polyethylene (HDPE) that are filled with freeze pack gel. When the vessel is frozen, core slabs up to 13 cm long may be positioned into a central chamber and then scanned following normal Itrax-uXRF-CS methodology. To test the
reliability of uXRF-CS analysis obtained from frozen sediments, a freeze core recovered from Control Lake, Northwest Territories, Canada, was sub-sectioned and analyzed using uXRF-CS and then subsampled for ICP-MS following near-total acid digestion.
Comparison of uXRF-CS and ICP-MS results showed strong correlations (R2 > 0.8) for six of nine elements calibrated, and moderate correlations (R2 > 0.3) for the remaining three. Additive log-ratio transformation of data minimized specimen, matrix and
edge effects associated with the high porewater contents of the freeze cores and slight melting of the sediment during analysis. These analytical effects had more impact on the lower concentration elements (As, Zn, Ni, Cu) than the higher
concentration elements (Ti, K, Mn, Fe, Ca). |
Summary | (Plain Language Summary, not published) This contribution provides a description of new technology for Itrax XRF core-scanning of frozen lake sediments cores. The freeze core containment vessel
described herein delays thawing of highly perishable freeze sediments for up to two hours, adequate time to conduct high resolution Itrax-XRF core scanning of the material. |
GEOSCAN ID | 308305 |
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