1. Classification of Stony Meteorites
EL (0.8%) opx, no oliv
Enstatite % Feo
(1.6%) EH (0.8%) opx, no oliv
- 25% Feo
H (30%) % Feo
Ordinary
(78%) L (40%) % Feo
Chondrites
(85-87%) LL (7%) % Feo
- chondrules
- oliv, opx, Feo
CV (1%) volatile depleted refractory lithophile enriched
- refractory inclusions
CO (1%) volatile depleted
STONES Carbonaceous matrix < 30%
< 30% Feo (4.8%) CM (2%) slight volatile depletion
(94-97%) matrix > 30%
CI (0.8%) volatile-rich
- hydrated silicates
- no oliv or chondrules
Aubrites enstatite & Fe alloy
Ureilites shock-melted carbonaceous chondrites?
(0.4%) olivine + Fe alloy, diamonds
Achondrites Lunar feldspar breccia
(10-12%)
SNC basaltic to ultramafic composition
(1%) shocked, young (1.4 bys)
- Martian rare-gas isotopic ratios
Eucrites basaltic composition
(2.8%) largely of opx & felds
- assoc: diogenites (opx) & howardites (breccias)
- old (4.5 bys)

2. Allende

4. Chondrite 32% Feo core + 68% mantle

5. 15 – 20 % melting
MgO = 37.8
Al2O3 =
SiO2 =
CaO =
FeO =
Total = 98.8

6. Primitive mantle:
MgO = 37.8
Al2O3 =
SiO2 =
CaO =
FeO =
Total = 98.8
Olivine ~ 55 %
Orthopyroxene ~ 30 %
Clinopyroxene ~ 15 %

8. MgO = 37.8
Al2O3 =
SiO2 =
CaO =
FeO =
Total = 98.8

9. Mg2SiO4
Y / T = 2
MgSiO3
Y / T =1
MgO = 37.8
Al2O3 =
SiO2 =
CaO =
FeO =
Total = 98.8

10. Ocean
Crust
Continental
Crust
Mantle

12. ? (Mg,Fe)3Al2(SiO4)3 Si = 3/8 or 37.50 Al = 2/8 or 25.00 NaAlSi3O8
MORB ?
(Mg,Fe)2SiO4
Si = 1/3 or 33.33
(Mg,Fe)SiO3
Si = 1/2 or 50.00

13. Chemical Probes
MORB
Hot-Spot
convecting upper mantle
Lower mantle ?

14. Source of Modern Hot-Spots ?

18. Exchange between the Mantle and Core ?
2(Mg,Fe)OMw FeOliq alloy MgOMw
2(Mg,Fe)SiO3Pv MgSiO3Pv SiO2 + FeOliq alloy
(Fe1-x,Mgx)SiO3Pv + 3(1-x)Feliq alloy xMgSiO3Pv + (1-x)FeOliq allo+ (1-x)Fe3Siliq alloy
oxidation of the mantle over time?
3Fe2+OMw or Pv Feoliq alloy Fe3+2O3perovskite

19. In the beginning ?

20. Mg#
~ 0.86

21. MORB