The 187Os/ 188Os ratios of spinel lherzolite xenoliths from Panshishan determined with N-TIMS are lower than that of the primitive mantle, which shows depleted mantle characteristics. Their positive correlation with A...The 187Os/ 188Os ratios of spinel lherzolite xenoliths from Panshishan determined with N-TIMS are lower than that of the primitive mantle, which shows depleted mantle characteristics. Their positive correlation with Al-2O-3/MgO suggests that the geochemical behavior of trace elements Re and Os is similar to that of Al-2O-3 and MgO respectively during the magmatic evolution and Re-Os isotopic system is largely immune to mantle metasomatism. A model age of 2 8-3 4 Ga obtained by 187Os/ 188Os-Al-2O-3/MgO correlation might represent the homogeneous age of the mantle lithosphere beneath the area.展开更多
文摘The 187Os/ 188Os ratios of spinel lherzolite xenoliths from Panshishan determined with N-TIMS are lower than that of the primitive mantle, which shows depleted mantle characteristics. Their positive correlation with Al-2O-3/MgO suggests that the geochemical behavior of trace elements Re and Os is similar to that of Al-2O-3 and MgO respectively during the magmatic evolution and Re-Os isotopic system is largely immune to mantle metasomatism. A model age of 2 8-3 4 Ga obtained by 187Os/ 188Os-Al-2O-3/MgO correlation might represent the homogeneous age of the mantle lithosphere beneath the area.