The RTF magma chamber

In the special case where x + y — 1, i.e. when the magma chamber is emptied then 

When Z) = 0, i.e. in the case of a totally incompatible trace element, 

Hagen and Neumann (1990) proposed that RTF processes are continuous rather than a series of cycles as suggested by O Plara and Matthews (1981) and their paper usefully includes the FORTRAN 77 code to implement the two models. 

Other elements are more soluble. For example, Fe, Mn, Pb and sometimes Cr are mobile during diagenesis. Cs, Rb and Ba are fixed during weathering but Sr is leached. Immobile elem as Zr, Hf and Sn may be mechanically distributed 

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