Trace elements incompatible behavior

Major and trace elements incompatible and compatible behavior... 

Fig. 2.1 The trace element behaviors of an incompatible element in the instantaneous fractional melt and extracted fractional melt.

During partial melting trace element behavior is governed by the preference of a particular element for its host (a mineral phase) or the melt phase. Elements which tend to become part of the melt are known as incompatible elements, and those which prefer to remain in the mineral phase are known as compatible elements. In detail this is governed by relationships between the particular element and the structure of the relevant mineral phase. The degree of incompatibility of a specific element in a particular mineral phase is expressed as the mineral-melt partition coefficient. Incompatible elements have mineral-melt partition coefficients <1.0 and highly incompatible elements have partition coefficients compatible elements have partition coefficients of > 1.0. 

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