Geothermal He and CO(2) variations at Changbaishan intra-plate volcano (NE China) and the nature of the sub-continental lithospheric mantle

Citation:
Hahm, D, Hilton DR, Cho M, Wei H, Kim KR.  2008.  Geothermal He and CO(2) variations at Changbaishan intra-plate volcano (NE China) and the nature of the sub-continental lithospheric mantle. Geophysical Research Letters. 35

Date Published:

Nov

Keywords:

basalts, carbon, fluids, helium, island, isotope, noble-gases, northeast china, volatile fluxes, xenoliths

Abstract:

We report new He and CO(2) data for geothermal fluids from Changbaishan Volcano located on the border of China and North Korea. Helium isotope ratios reach a maximum of 5.4 R(A) (where R(A) = (3)He/(4)He in air) whereas carbon isotope values (delta(13)C) fall between -2 and -7%(vs. PDB). The ratio of CO(2)/(3)He varies between 0.5-7.1 (x 10(9)) for gas samples but is considerably higher (similar to 10(12)) in waters. The combined He-CO(2) systematics reveal the clear imprint of a dominant subducted slab contribution to the total CO(2) inventory. We conclude that these geothermal volatiles originate from the sub-continental lithospheric mantle (SCLM) in NE China and represent ancient fluids captured by prior metasomatic events. Citation: Hahm, D., D. R. Hilton, M. Cho, H. Wei, and K.-R. Kim (2008), Geothermal He and CO2 variations at Changbaishan intra-plate volcano (NE China) and the nature of the sub-continental lithospheric mantle, Geophys. Res. Lett., 35, L22304, doi:10.1029/2008GL035955.

Notes:

n/a

Website

DOI:

10.1029/2008gl035955

Scripps Publication ID:

L22304