~1x. the highest resolution models resolve about 20 discrete llvas below the usual lvz

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Page 1: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

~1X

Page 2: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 3: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Page 4: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 5: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 6: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 7: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 8: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 9: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Heated from below gives narrow upwellings and broad downwellings. Cooling from the top and internal heating give the opposite.

Fig. 11. Numerical simulation of convection in a fluid with viscoelastic rheology and a yield stress showing temperature (top) and the second invariant of stress rate (bottom). For a suitable range of Rayleigh number and yield stress the surface velocity, vx, breaks up into a number of distinct ‘plates’.

Page 10: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Heated from below gives narrow upwellings and broad downwellings. Cooling from the top and internal heating give the opposite.

Fig. 11. Numerical simulation of convection in a fluid with viscoelastic rheology and a yield stress showing temperature (top) and the second invariant of stress rate (bottom). For a suitable range of Rayleigh number and yield stress the surface velocity, vx, breaks up into a number of distinct ‘plates’.

Hawaii

ridgesuperswell

Page 11: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 12: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Ridge Related Upwellings

Shallow lateral flow (fingers) either away from ridges (ridge centered upwellings) or toward ridges/thin spots (off axis upwellings).

Page 13: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Cooled from above…

Page 14: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 15: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 16: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Low sound speed(?) but dense

Page 17: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 18: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 19: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 20: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 21: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

1, Hawaii; 2,Samoa; 3, Marquesas; 4, Tahiti 5, Pitcairn; and 6, Macdonald.

Page 22: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Hawaii

Galapagos Easter

Page 23: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

fingers

superswell

42

S.Of AlaskaW. Of Calif.

-2%+3%

Page 24: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 25: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

Downwellings?

Page 26: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

cold warm cool cold

Most hotspots, backtracked LIPs & kimberlites fall within the ~ -2% contour surrounding ridges (p=10-8)

Harvard

In spite of being ‘passive’, ridge-related upwellings are not ambient or ‘representative’ shallow mantle

Dziewonski&Ekstrom

Page 27: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ

HawaiiTonga

ridge

800

Page 28: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ
Page 29: ~1X. The highest resolution models resolve about 20 discrete LLVAs below the usual LVZ