Experimental study of ore gabbro liquid immiscibility
In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900-1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.
作 者： SANG Zunan XIA Bin ZHOU Yongsheng JIN Zhenmin 作者单位： SANG Zunan(Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Wuhan University,Wuhan 430072,China)XIA Bin(Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China)
ZHOU Yongsheng(Institute of Geology, China Seismological Bureau, Beijing 100029, China)
JIN Zhenmin(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China)
刊 名： 中国科学D辑（英文版） SCI 英文刊名： SCIENCE IN CHINA SERIES D: EARTH SCIENCES 年，卷(期)： 2005 48(4) 分类号： P3 关键词： partial melting experimental study gabbro liquid immiscibility ore formation mechanism