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New Investigation of a Greenland ice core platinum anomaly near the Bølling-Allerød/Younger Dryas boundary
Oxytropidoceras posted a topic in Fossil NewsGreen, C. E., 2019. Investigating the origin of a Greenland ice core geochemical anomaly near the Bølling-Allerød/Younger Dryas boundary (Doctoral dissertation, Durham University). http://etheses.dur.ac.uk/13490/ http://etheses.dur.ac.uk/13490/1/C_Green_thesis_final_CORRECTIONS.pdf Green (2019) noted: "The source of a platinum peak identified in the Greenland Ice Sheet Project 2 (GISP2) ice core associated with high platinum/iridium (Pt/Ir) and platinum/aluminium (Pt/Al) ratios, and previous research attributed the anomaly to an unusual iron-rich Ir-poor meteorite impact." Green (2019) concluded: I. the Laacher See eruption is not the Pt spike source because: A. the Laacher See tephra has low Pt concentrations, B. the Laacher See tephra’s geochemical ratios are dissimilar to the GISP2 Pt spike and C. conversion of the Pt spike timing to the newest ice core age-depth model shows a chronological offset of ~60 years between the two events. II. The event resulting in the Pt spike occurred ~60 years after GS-1 cooling, and was therefore not the primary trigger. III. and the Pt spike origin is interpreted as either: A. a noncataclysmic impact of an undiscovered iron meteorite B. or an unidentified Pt-rich volcanic eruption contemporaneous with the anomaly, whose aerosol fractionated in the atmosphere or ice. Yours, Paul H.