来自海地的白垩纪-第三纪边界玻陨石的40Ar/39Ar年龄

40Ar/39Ar Age of Cretaceous-Tertiary Boundary Tektites from Haiti.

作者信息

Izett G A, Dalrymple G B, Snee L W

出版信息

Science. 1991 Jun 14;252(5012):1539-42. doi: 10.1126/science.252.5012.1539.

DOI:10.1126/science.252.5012.1539

Abstract

(40)Ar/(39)Ar dating of tektites discovered recently in Cretaceous-Tertiary (K-T) boundary marine sedimentary rocks on Haiti indicates that the K-T boundary and impact event are coeval at 64.5 +/- 0.1 million years ago. Sanidine from a bentonite that lies directly above the K-T boundary in continental, coal-bearing, sedimentary rocks of Montana was also dated and has a (40)Ar/(39)Ar age of 64.6 +/- 0.2 million years ago, which is indistinguishable statistically from the age of the tektites.

摘要

最近在海地白垩纪-古近纪（K-T）边界海洋沉积岩中发现的玻陨石的氩-氩（Ar/Ar）年代测定表明，K-T边界和撞击事件发生在同一时期，即6450万年前，误差范围为正负0.1百万年。对蒙大拿州含煤大陆沉积岩中位于K-T边界正上方的膨润土中的透长石也进行了年代测定，其氩-氩（Ar/Ar）年龄为6460万年前，误差范围为正负0.2百万年，在统计学上与玻陨石的年龄无法区分。