Carbonatite Metasomatism in the Southeastern Australian Lithosphere
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چکیده
New mineralogical and geochemical data from a suite of glass ± from the mantle (Deines & Gold, 1973; Nelson et al., 1988). However, controversy remains as to whether such apatite ± amphibole ± phlogopite ± carbonate-bearing spinel magmas represent (1) direct partial melts of carbonatewehrlite, lherzolite and harzburgite xenoliths from the Newer Volbearing mantle peridotite (i.e. primary carbonatites; Wylcanics, southeastern Australia, are consistent with metasomatic lie & Huang, 1975; Wallace & Green, 1988; Sweeney, interactions between harzburgitic or refractory lherzolitic lithosphere, 1994), (2) primary carbonatites modified by interactions and penetrative sodic dolomitic carbonatite melts. Metasomatism with peridotite wall-rock in the upper mantle (Wallace occurred when ascending dolomitic carbonatites crossed the reaction & Green, 1988; Dalton & Wood, 1993; Sweeney et al., enstatite+ dolomite= forsterite+ diopside+CO2 at ~1·5–2·
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