Strontium isotope geochemistry of archaeological human tooth enamel excavated from Jeonju, southwestern Korea

摘要

Strontium isotopes of archaeological skeletal tissues have provided useful information to trace past human migration. This study presents strontium isotope data of human tooth enamel excavated from a group of medieval Joseon tombs in Jeonju, southwestern Korea. The enamel samples are divided into two isotopic populations yielding average Sr-87/Sr-86 of 0.71077 +/- 0.00031 (group I) and 0.71233 +/- 0.00032 (group II). Considering the gender distribution, Sr-87/Sr-86 ratios of group I may better represent the local value of biologically available strontium. Contrasting Sr-87/Sr-86 patterns of acetic acid extracts and residues of enamel fragments from a male of group I and a female of group II suggest their different residential mobility during childhood. The Sr-87/Sr-86 range of group I enamel is considerably lower than that reported from basement granites in the Jeonju area. Strontium in this group may have been conveyed from rainfall, and soluble soil fractions composed mainly of low-Rb/Sr minerals such as plagioclase.