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7462305 
Journal Article 
THE EFFECT OF TSCHERMAK SUBSTITUTION ON ASSEMBLAGES IN ALUMINOUS DOLOMITES 
Baker, J; Holland, TJB; Powell, R 
1994 
Yes 
Contributions to Mineralogy and Petrology
ISSN: 0010-7999
EISSN: 1432-0967 
SPRINGER VERLAG 
NEW YORK 
118 
1 
48-59 
WOS:A1994PN75600004 
A calculated petrogenetic grid for the system CaO-MgO-Al2O3-SiO2-CO2-H2O (CaMASCH), incorporating Tschermak's substitutions in amphibole, chlorite, talc and clinopyroxene, is used to examine phase relationships in aluminous marbles. A series of diagrams illustrating the effect upon stable mineral assemblages of increasing the aluminium content of a bulk composition is used to show the way aluminous minerals enter mineral assemblages in progressively more aluminous rocks. The effects of changing pressure and the incorporation of Fe into the bulk composition on the stable mineral assemblages are also examined. The calculated equilibria are shown to be in reasonable agreement with natural assemblages, and the incorporation of new experimental data on amphiboles into the existing dataset is shown to improve the agreement between observed and natural amphibole compositions.