1. The results of the experiment indicate that the early crystallization sequence of the liquid is dominated by Fe-Ti oxide and can explain why the largest oxide ore deposits of the Panzhihua intrusion are found in the lowermost layers.
2. The early crystallization of Fe-Ti oxide probably results from high-Ti content of parental magma composition. The assimilation of carbonate wall rock may be not necessary for the formation of ore deposits.
3. The residual glass compositions at low-pressure condition become more silicic, resemble spatially associated peralkaline silicic rocks found in close proximity to the layered gabbro and suggest that the two rock types form a coherent igneous complex. It also suggests that the Panzhihua magma was formed at shallow depth.
4. The liquid-crystal evolution constructed from the experiment show that a parental magma similar to high-Ti Emeishan basalt can produce an early enrichment of oxide minerals and a silicic residual liquid through fractional crystallization, suggest that the formation of ore deposits as well surrounding A-type granite results from fractional crystallization and that silicate immiscibility is not required.
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71 Appendix
EPMA data of atmospheric-pressure experiment sample showing major elements weight percent.
Sample Temperature
72
73
74
75
76
77
78
79
80
81
Pz-002 1102 1 Glass_avg 67.20 0.86 16.11 0.01 2.94 0.08 1.79 4.54 3.14 3.33 100.04
EPMA data of high-pressure experiment sample showing major elements weight percent.
Sample Temperature
82
83
84
85
86