<P> Continental crust is the layer of igneous , sedimentary , and metamorphic rocks that forms the continents and the areas of shallow seabed close to their shores , known as continental shelves . This layer is sometimes called sial because its bulk composition is richer in silicates and aluminium minerals and has a lower density compared to the oceanic crust , called sima which is richer in magnesium silicate minerals and is denser . Changes in seismic wave velocities have shown that at a certain depth ( the Conrad discontinuity ) , there is a reasonably sharp contrast between the more felsic upper continental crust and the lower continental crust , which is more mafic in character . </P>
<P> Continental crust is the layer of igneous , sedimentary , and metamorphic rocks that forms the continents and the areas of shallow seabed close to their shores , known as continental shelves . This layer is sometimes called sial because its bulk composition is richer in silicates and aluminium minerals and has a lower density compared to the oceanic crust , called sima which is richer in magnesium silicate minerals and is denser . Changes in seismic wave velocities have shown that at a certain depth ( the Conrad discontinuity ) , there is a reasonably sharp contrast between the more felsic upper continental crust and the lower continental crust , which is more mafic in character . </P>
what is formed on top of continental crust
what is formed on top of continental crust
felsic
felsic