Question

Suppose we move a piece of dry peridotite from the geotherm at 250 km upward by 75km. Is this rock solid or molten?

What about when we move it uo another 100km

500 Temperature (°C) 1.000 1.500 2,000 Crust solid melt Moho Lithospheric mantle Geotherm 100 200 Asthenosphere Depth km) (O'T X SIPA) pincea $ 300 100 Melting curve (dry peridotite) 400 500 11:03 150

Answer 1

1 - from 250km to 75km upward

- ans - solid

As it not touched the melting curve of dry peridotite yet . If its wet peridotite the there is chances of molten

2 - from 175km depth to 75km depth

Ans - molten

As it already crossed the melting curve of dry peridotite .

NOTE - The solid red line is solid curve means all are in solid state below it , the dotted red line is melting curve

means all the material above it is in molten state . In between these two line only wet materials are in molten state .