Integrated Compositions of Perfect Fractional Liquid and Solid Products are Identical, with Respect to Ideal Trace Element Behaviour, to Simple Equilibrium (Batch) Products in Very Special Cases

Abstract

of liquid involved are zero and unity; and that the Partial melting of natural rocks is likely to proceed with bulk crystal–liquid distribution coefficient, d, is assumed the pooling of liquids which have been produced by a constant throughout each of the processes. range of mass fractions of liquid development (O’Hara, Given the first two conditions listed above, the average 1985, 1995; Richter, 1986; Langmuir, 1989; Eggins, mass fraction of liquid, f av, developed in linear planform 1992; Plank & Langmuir, 1992; O’Hara & Fry, 1996). circumstances must be ( f max+ f min)/2, and given the third Partial crystallization of magmas in magma chambers condition this expression must have the value 0·5 (circular may involve the integration of residual liquids from a planform circumstances are mentioned briefly below). range of mass fractions of liquid survival either through The relationship between C L, the concentration of an the crystallization zone or across the crystallizing surface element in the equilibrium (batch) partial melting (EPM ) (Langmuir, 1989; O’Hara & Fry, 1996). The conor equilibrium partial crystallization (EPC) liquid, and centrations of ideally behaved trace elements in an inC S, the concentration of the element in the source tegrated liquid or solid and that in the product of a simple material which began to undergo partial melting or process operating at the same average mass fraction of crystallization, is obtained from liquid in the system are, in general, significantly different (O’Hara, 1995; O’Hara & Fry, 1996). However, under CL CS = 1