Al-rich metapelites from the Mashan khondalite series are characterized by the assem- blage Spl+Grt+Sil+Crd+Bt+Pi (An72)+Kfs+Quartz+graphite. Large amounts of spinel+quartz assem- blages occur as inclusions...Al-rich metapelites from the Mashan khondalite series are characterized by the assem- blage Spl+Grt+Sil+Crd+Bt+Pi (An72)+Kfs+Quartz+graphite. Large amounts of spinel+quartz assem- blages occur as inclusions in garnet and prismatic sillimanite in the Ai-rich metapelites of the Mashan complex, NE China. The chemical composition of spinel is characterized by Zn-rich (Xzn=0.33-0.40. Xzn=Zn/Zn+Mg+Fe*) (Fe*=FeZ++Fe3+) and Fe3+ rich (up to 0.31 p.f.u.). The characteristic chemical composition and the mineral association indicated that the formation of spinel and quartz assemblage may be due to the breakdown of Zn-rich staurolite. The geothermobarometers studies show that the peak temperature of the Mashan complex is around 820 ℃ and the peak pressures is 8.0 kbar. The Mashan complex shows a typical orogen style P-T path.展开更多
基金supported by a JSPS Grant-in-Aid for Scientific Research (No. 17340149) to Akira Takasuby the NSFS of China (No. 40739905) to Yongjiang Liu+1 种基金by the 973 project of the Ministry of Science and Technology of China (No. 2013CB429802)by the National Natural Science Foundation for the Youth of China (No. 41302175) to Weimin Liu
文摘Al-rich metapelites from the Mashan khondalite series are characterized by the assem- blage Spl+Grt+Sil+Crd+Bt+Pi (An72)+Kfs+Quartz+graphite. Large amounts of spinel+quartz assem- blages occur as inclusions in garnet and prismatic sillimanite in the Ai-rich metapelites of the Mashan complex, NE China. The chemical composition of spinel is characterized by Zn-rich (Xzn=0.33-0.40. Xzn=Zn/Zn+Mg+Fe*) (Fe*=FeZ++Fe3+) and Fe3+ rich (up to 0.31 p.f.u.). The characteristic chemical composition and the mineral association indicated that the formation of spinel and quartz assemblage may be due to the breakdown of Zn-rich staurolite. The geothermobarometers studies show that the peak temperature of the Mashan complex is around 820 ℃ and the peak pressures is 8.0 kbar. The Mashan complex shows a typical orogen style P-T path.