1. Links between melting, rheology and the composition and structure of the upper mantle Greg Hirth, Brown Univeristy Marc Parmentier & Alberto Saal Mark Behn, Jim Gaherty, John Collins, Dan Lizarralde Kiyoshi Baba, Rob Evans, Alan Chave, Don Forsyth Joerg Renner, Karen Viskupic, Brian deMartin & Brian Evans

2. Cagnioncle et al. 2007 Hirth & Kohlstedt, 2003 Zhao et al. 2007

3. Gaherty et al., 1999

4. Mei & Kohlstedt, 2000; Jung & Karato, 2001; Borch & Green, 1989; Chopra & Paterson, 1981; Karato et al., 1986 Hirth & Kohlstedt, 2003 Influence of water of rheology ( Strain Rate  [Viscosity] -1 )

6. Evans et al., 2005 Resistive layer consistent with dry olivine Conductive “asthenosphere” consistent with damp olivine Magnitude of anisotropy consistent with crystallographic dependence of H diffusion in Olivine Anisotropy hard to preserve if conductive layer controlled by presence of melt

7. [100] [010] [001] [100] [010] [001] Basaltic Melt: 10 S/m Fictive Melt: 100 S/m (S/m)

8. Enriched (650 ppm) Depleted (85 ppm) Two Component Mantle with 125 ppm Bulk Water

9. Yang, Weeraratne & Forsyth dehydratation

10. Faul & Jackson, 2005 0 100 200 300 400 Vs

11. Behn et al., 2009

14. Need constraints on permeability (k) and bulk viscosity (  )

16. Olivine + Melt 1200 o C,  P = 10 MPa grain size = 20  m rate   1 rate   2 Renner et al., 2003 Predicts  > 10 22 Pas

17. n = 1 n = 3.5 “shear”  = 1% Compaction Rate   P n  =  P/Compaction Rate  P =  g   g  7000 (SI)  = 300 km gives  P = 2.1 GPa!! NO WAY

18. deMartin, Hirth & Evans

19. S  = Carbonate melt flux S  = Fcarb*Upwelling flux Upwelling flux = volume/area/time Upwelling flux = Slab Flux/Earth surface area Upwelling Flux = 1km/yr Fcarb = 10 -4 to 10 -3

20. F = 0.01% F = 0.1%  -2  -1 Darcy Flux  = 0.01% Ponded Melt Fraction t = (  pond /3)  (  )/S 

21. Dasgupta et al., 2009 “Ponded”   2% Crystallize H 2 0  400 ppm