Proceedings of the Mineralogical Society of Korea Conference (한국광물학회:학술대회논문집)
- 2000.05a
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- Pages.19-19
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- 2000
A geothermal gradient of the upper mantle beneath Jeju-do, Korea: evidence from mantle xenoliths
- Choi, Seong-Hee (Natural Science Research Institute, Yonsei University) ;
- Jwa, Yong-Joo (Department of Earth & Environmental Science, Gyeongsang National University) ;
- Lee, Han-Yeang (Korea Institute of Geology, Mining and Materials(KIGAM))
- Published : 2000.05.01
Abstract
;Ultramafic xenoliths found in alkali basalts from Jeju-do, Korea are mostly spinel Iherzolites composed of olivine, orthopyroxene, clinopyroxene and spinel. A subordinate amount of spinel harzburgites and pyroxenites are also found. Temperatures for these xenoliths were estimated from the compositions of coexisting pyroxenes (Wood '||'&'||' Banno 1973; Wells 1977; Bertrand '||'&'||' Mercier 1985; Brey '||'&'||' Kohler 1990), the AI-solubility in orthopyroxene coexisting with olivine and spinel (Sachtleben '||'&'||' Seck 1981; Webb '||'&'||' Wood 1986), and from Fe/Mg partitioning between olivine and spinel (Ballhaus et al. 1991). Temperature estimates from the thermometers by Wells (1977) and Brey and Kohler (1990) are compatible. Average equilibrium temperatures by these two methods for spinel peridotites range from 890 to 1030
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