This particular null may have occurred because the subducted slab was in contact with relatively cool continental lithosphere, not hotter asthenosphere.
32.
The buoyant fluids then rise into the asthenosphere, where they lower the melting temperature of the mantle and cause partial melting.
33.
The heat expelled by the magma expands the lithosphere and asthenosphere at the ridge, pushing them above the surrounding ocean floor.
34.
However, most scientists working today believe that the asthenosphere does not directly cause motion by the friction of such basal forces.
35.
Oceanic lithosphere is less dense than asthenosphere for a few tens of millions of years but after this becomes increasingly denser than asthenosphere.
36.
Oceanic lithosphere is less dense than asthenosphere for a few tens of millions of years but after this becomes increasingly denser than asthenosphere.
37.
Plumes are postulated to rise through the mantle and begin to partially melt on reaching shallow depths in the asthenosphere by decompression melting.
38.
In plate tectonics, the horizontal movement of tectonic plates over the Earth's soft asthenosphere causes horizontal forces within the crust.
39.
More recent studies by Explorer and Juan de Fuca Plates, the subducted plate asthenosphere may possibly flow upward into the mantle wedge.
40.
The abyssal plain is formed when the lower oceanic crust is melted and forced upwards by the asthenosphere layer of the upper mantle.
