Ultra-High Resolution Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) measurements of Younger Dryas onset in the Greenland Ice Sheet Project 2 (GISP2) ice core, Greenland

• Main Author: Sneed, Sharon
• Format: Dataset
• Language: English
• Published: Arctic Data Center 2017
• Subjects: EARTH SCIENCE > CRYOSPHERE > SNOW/ICE > SNOW/ICE CHEMISTRY; IN SITU/LABORATORY INSTRUMENTS > SPECTROMETERS/RADIOMETERS > MASS SPECTROMETERS; Greenland; Greenland ice core; Greenland Ice Sheet Project; ice core; Ice Sheet
• Online Access: https://dx.doi.org/10.18739/a2ms3k19n; https://arcticdata.io/catalog/#view/doi:10.18739/A2MS3K19N

This data set contains the results of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) performed on an archive of the GISP2 ice core containing the Younger Dryas onset. There are two sets of files from two sections of core samples, one with measurements of Ca, Na, and Fe concentrations at the same depth, and three files with those same measurements from a different section of the core. The primary objective of the research was to obtain records of platinum, iridium, and osmium concentrations and osmium isotope ratios in the GISP2 Greenland ice core in order to investigate the hypothesis that there was a meteorite or comet impact at the onset of the Younger Dryas abrupt climate event 12,900 years ago. These analyses are combined with high-resolution measurements of climate proxies obtained on the same samples. Osmium isotopes have the potential not only to conclusively confirm or refute the presence of an extraterrestrial impact, but also to provide information about the size and type of the impactor, should one be confirmed. High-resolution analyses of the atmospheric circulation proxies sodium, calcium, and iron represent a leap in ice core analysis resolution from one sample per three years to over 100 samples per year. The research activities contribute towards an understanding of what happened at the Younger Dryas, which will be of broad interest to geologists, geochemists, climatologists, archeologists, astronomers, and the general public. Following recent reports of a large anomaly in platinum concentration in the GISP2 ice core, four investigators performed a series of collaborative analyses at Dartmouth College and the University of Maine on GISP2 ice core samples of Younger Dryas age to: (1) evaluate the platinum spike at the Younger Dryas onset for potential contamination and contributions from volcanic and terrestrial sources, (2) measure osmium concentration and isotope composition to evaluate whether an impact occurred at the Younger Dryas onset and assess the nature of any impactor, and (3) assess the environmental change across this critical climate transition by measuring iron, sodium and calcium at storm-scale resolution using a new laser ablation mass-spectrometry system.