Host: Abstracts of Annual Meeting of the Geochemical Society of Japan
Name : Abstracts of Annual Meeting of the Geochemical Society of Japan
Number : 71
Date : September 18, 2024 - September 20, 2024
Pages 105-
Recently, our research has focused on six sites of K-Pg boundaries in Colorado and North Dakota in the United States. The primary focus of this study is the North Dakota formation named Pyramid Butte (PB). The K-Pg boundary at this site is a peat layer about 5 cm thick containing spherulite, below which is a peat layer about 1 m thick in total thickness and above which is a silt layer about 1 m thick in total thickness. The silt layer showed significantly higher concentrations of SiO2, Sc, Ce, Nd and Th than the peat layer. No Ir spike (>>1 ppb) was observed in the K-Pg layer, but significantly higher quantitative values of Ni were obtained in the uppermost 5-10 cm portion of the peat layer. For Cr, higher values were obtained in the K-Pg layer and up to the lower 10 cm of the silt layers.
