(super 14) C level at Mt. Chiak and Mt. Kyeryong in Korea.

Abstract

We have observed Delta (super 14) C concentrations in the northern hemisphere temperate region in the bomb pulse period, using cross-dated tree ring samples. The tree-ring samples were taken from one 70-year-old and two 50-year-old red pines (Pinus densiflora) on Mt Chiak, Korea and from a 50-year-old red pine (Pinus densiflora) on Mt Kyeryong, Korea. Twenty-two tree-ring samples from four red pines ranging from 1950 to 2000 AD were pretreated to obtain holo-cellulose, combusted to CO (sub 2) by an element analyzer (EA) and converted to graphite for Delta (super 14) C measurement using the accelerator mass spectrometry (AMS) facility at Seoul National University. Our results for Delta (super 14) C showed good agreement with those measured by other researchers at similar latitudes. The observed steady decrease of Delta (super 14) C from 1965 to 2000 AD is described by a single exponential function with a lifetime tau = 15.99+ or -0.43 yr. This lifetime is similar to that of the high-latitude region in Europe.