0 the thin, almost liquid, layer under the hard rock that forms the outer layer of the earth
1 the thin, almost liquid, layer under the hard rock that forms the outer layer of the earth
In continental rift settings, the emplacement of such large volumes of felsic melts requires a huge amount of mafic magma derived from uprising asthenosphere.
Either of these mechanisms can cause the hot asthenosphere to rise close to the metasomatized lithosphere, initiating melting.
In particular, is the source of within-plate basaltic magmas in an extensional setting the lithosphere, convecting asthenosphere or both?
The extension of lithosphere accompanied with the upwelling of asthenosphere may be the key factor for the coeval magmas with different sources.
We therefore favour the model whereby the eclogitic lower crust, together with the underlying lithospheric mantle, was delaminated, accompanied by asthenosphere upwelling.
However, the contribution of asthenosphere to the generation of mafic magmatism would become ever greater along with the increase in extension of the lithosphere.
The second chapter discusses the lithosphere and asthenosphere and the important role water plays in defining the brittle and ductile behaviour of the rocks in these regions.
Temperatures high enough to produce basaltic partial melt in this decaying thermal anomaly would be located near the base of the lithosphere and in the immediately underlying asthenosphere.
