Contrasting partition behavior of F and Cl during hydrous mantle melting: implications for Cl/F signature in arc magmas

Progress in Earth and Planetary Science

Table 6 Bulk partition coefficients and data used in fluid induced melting model

	α	D _{o Cl} ^{bulk a}	D _{o F} ^{bulk a}	P _Cl ^bulk	P _F ^bulk	Samples used to calculate D _o ^bulk	For phases:
Spinel lherzolite
Dry melting	0.002	0.002(0.6)	0.056(2)	0.006(0.7)	0.157(4)	CD1 H0	Ol,^bopx, cpx
Low degree of metasomatism	0.026	0.009(0.5)	0.032(0.4)	0.016(0.8)	0.099(1)	CD2H3	Ol, opx, cpx
Intermediate degree of metasomatism	0.049	0.014(0.8)	0.024(2)	0.027(1)	0.072(4)	CD2H3	Ol
Intermediate degree of metasomatism	0.049	0.014(0.8)	0.024(2)	0.027(1)	0.072(4)	CD2H5	Opx, cpx
High to very high degree of metasomatism	0.059	0.023(3)	0.018(9)	0.044(5)	0.061(18)	CD2H3	Ol
						CD2H6	Opx
						CD2H5	Cpx
Amphibole-bearing wehrlite
Intermediate degree of metasomatism	0.043	0.066(23)	0.219(0.2)	0.130(48)	0.398(72)	CD2H3	Ol
						CD2H4	Amp
						CD2H5	Cpx
High to very high degree of metasomatism	0.059	0.201(43)	0.353(0.3)	0.411(87)	0.695(95)	CD2H3	Ol
						CD2H6	Amp
						CD2H5	Cpx

^aFrom Johnson et al. ([1990]).
^bFrom Hauri et al. ([2006]), we used average value of D _F and D _Cl between olivine and basaltic melt.
D _o ^bulk = Σ D _i ^mineral/melt · X_i ^mineral, where X is the proportion of mineral in the anhydrous lherzolite and D _i ^mineral/melt are presented Table 5.
P _i ^bulk = Σ D _i ^{mineral /melt} · p _i ^mineral, where p are the stoichiometric coefficients of melting (see text).
D _i ^bulk = [D _o ^bulk − (P _i ^bulk · χ)]/(1 − χ), where χ is the degree of melting.