Partial melting

[HaranHennig]

Hi Paula/Paul,
I have a chemical analysis of Spinel-Hertzburgite Xenolite which i would like to partial-melt at ~9 Kbar and approx. 1200 c  , to see which % melting could be my parental melt for the field assemblage.
the P/T was determined previously using melt inclusions.
The problem:
at those conditions, if i just enter the *.melts file and using the manu "option 3" the program gives a ~3.5% melt which is ultra-low on silica(22%).
I would expect to form at least 40% silica in a 3.5% partial melt liquid or even higher than that, without getting to 20+% partial melting which is unreasonable for me.

file used:
Title:Xenolite smp. BH-16-G Hertzburgite
Initial Composition: SiO2 44.06
Initial Composition: TiO2 0.055
Initial Composition: Al2O3 1.15
Initial Composition: Fe2O3 1.49
Initial Composition: FeO 9.18
Initial Composition: MnO 0.165
Initial Composition: MgO 42.72
Initial Composition: CaO 1.48
Initial Composition: Na2O 0.19
Initial Composition: K2O 0.04
Initial Composition: P2O5 0.03
Initial Temperature: 1200.00
Initial Pressure: 9000.00
Log fO2 Path: none

and the results:
Initial alphaMELTS calculation at: P 9000.000000, T 1200.000000
liquid: 3.410 g 22.07 0.28 0.40 33.31 35.82 0.01 4.19 0.22 3.63 0.01 0.06
Activity of H2O = 0  Melt fraction = 0.0339143
olivine: 70.503555 g, composition (Ca0.00Mg0.90Fe''0.10Mn0.00Co0.00Ni0.00)2SiO4
orthopyroxene: 21.148919 g, composition opx Na0.01Ca0.05Fe''0.17Mg1.68Fe'''0.03Ti0.00Al0.15Si1.91O6
clinopyroxene: 5.241394 g, composition cpx Na0.06Ca0.72Fe''0.10Mg0.93Fe'''0.06Ti0.01Al0.26Si1.86O6
leucite: 0.194745 g, composition K0.94Na0.06AlSi2O6.00(OH)0.00
whitlockite: 0.061 g, composition Ca3(PO4)2


AM i doing it right? or is it another way of approaching this kind of calculation?
thank you,
Haran.