【摘 要】
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A series of crystallization experiments have been carried out by using natural Emeishan Ti-rich hydrous basalts as starting materials at a pressure of 0.5 GPa and temperatures of 800-1000 °C to constrain the origin of Fe-Ti-V oxide ore deposits. Our exper
【机 构】
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State Key Laboratory of Geological Processes and Mineral Resources,School of Earth Sciences,China Un
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A series of crystallization experiments have been carried out by using natural Emeishan Ti-rich hydrous basalts as starting materials at a pressure of 0.5 GPa and temperatures of 800-1000 °C to constrain the origin of Fe-Ti-V oxide ore deposits. Our experimental results demonstrate that the sandwich-and trellis-type ilmenite lamellae in titanomagnetite of layered intrusions can be formed by the reaction of earlier crystallized ilmenite and the evolved parental magma. During evolution of paren- tal basaltic magma, the Fe-Ti oxide should be composed of titanomagnetite+ilmenite in the earlier stage, but changed to titanomagnetite+titanomagnetite-ilmenite intergrowth±ilmenite at the later stage. Accordingly, the Panzhihua Fe-Ti oxide ores, which are mainly composed of titanomagnetite, should be formed earlier than the adjacent gabbro, in which titanomagnetite-ilmenite intergrowth is the major form of the Fe-Ti oxide.
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