Melt Delivery from the Mantle to the Crust

Selected Reading:

G. Ceuleneer, A. Nicholas, and F. Boudier, Mantle Flow Patterns at an Oceanic Spreading Centre:
The Oman Peridotite Record.  Tectonophysics, 151, 1988.

P. Kelemen, G. Hirth, N. Shimizu, M. Spiegelman, and H. Dick, A Review of Melt Migration
Processes in the Adiabadically Upwelling Mantle benath oceanic spreading ridges.
Phil. Trans. Roy. Soc. London, Ser. A, 1997.

For extra credit and some easier reading:  Chapters 6 and 7 of Adolph Nicholas' Book:  The Mid-Oceanic Ridges.
 

Outline

I.  Introduction
• A Cross-Section Through an Ophiolite
• How much of the ridge system is contained in an ophiolite
 

II. Mantle (matrix) Flow Patterns Observed in Ophiolites

• Structural Mapping of Anisotropic Fabric
• Homogeneous Flow (observed in 70% of the ophiolite)
• Diapiric like flow patterns
• Vertical flow and radial horizontal flow
 

III. Melt Migration Processes in the asthenosphere: ophiolite observastions

• Pervasive Porous Flow
• Dikes and cracks
• Flow in Porous "Dissolution" Channels of dunite
 

IV. Summary of the Observations
• Is there a coupling between matrix flow and melt migration?