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Cui Liu, China University of Geosciences & Chinese Academy of Sciences (China)
Jinfu Deng, China University of Geosciences (China)
Desheng Li, Geology Survey Institute of Shanxi Province (China)
Jihua Zhou, Geology Survey Institute of Shanxi Province (China)
Zhenxiang Zhao, Geology Survey Institute of Shanxi Province (China)
Zhanliang Sun, Geology Survey Institute of Shanxi Province (China)
Fengqing Zhao, Institute of Geology and Mineral Resourcesof Tianjin (China)
Shangguo Su, China University of Geosciences (China)
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There is not report about High-Mg Andesite (=boninite) (HMA) in the Neoarchean greenstone belt of Wutai mountain area (e.g. Kusky,2003) recently. We have recognized the HMA of this greenstone belt.
Several definitions for the HMA are suggested, after Crawford (1989) et al. the HMA are w(SiO2)53%, Mg# 0.6. After LeMaitre (1989), the HMA are that w(SiO2)53%, w(MgO)8% and w(TiO2)0.5%. And w(SiO2)52% are suggested by Le Bas(2000). We suggest the HMA are w(SiO2)52%, Mg#≥0.6, w(MgO)≥ 5.7 and the ratio of FeO(total Fe 2+ )/MgO 1.5 based on datas of petrological experiments. (Deng Jinfu et al.,2007a;Deng Jinfu,2007b).
The HMAs in the Neoarchean greenstone belt of Wutai Mountain area, North China are SiO2: 52%~63 wt%, MgO: 6 ~10.5 wt% with highest of 26 wt%, Mg# ≥0.6; and FeO/MgO ratio1.38.
The recognition of the HMA in the Neoarchean greenstone belt of Wutai Mountain area suggest the SSZ-setting for the greenstone belt.
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