Introduction to the Earth's Layer's
![Picture](/uploads/2/0/7/2/20721316/1370089563.jpg)
The earth is made of many layers which are defined by compositional and rheological properties.
The composition, based on chemical constituents, are listed with name and depths and correspond to Fig. 1.
Compositional layers
Crust: Average 7km for oceanic and Average 40km for continental. Basalt and silicates.
Mohorovičić discontinuity: seismic discontinuity at the base of the crust
Upper mantle: 40km -410km and consists of the lithospheric mantle and the plastic mantle
Asthenosphere: Made up of 60% Olivine and 40% Mg, Fe, Al and Ca silicates
Transition zone: 410 km-660km Olivine into denser wadyselite and garnet
Lower mantle: 660km No silicates, only Mg, Fe and Al oxides.
Rheological layers
The lithosphere includes the lithospheric mantle and lithospheric crust, both solid layers which will deform in a brittle nature at shallow depths and a ductile nature as the temperature rises and the rock weakens. The asthenosphere consists of 5% melt and will flow away from lithospheric stress making it a plastic material.
Figure 1: Layers of the earth
(Watson, 2009)
The composition, based on chemical constituents, are listed with name and depths and correspond to Fig. 1.
Compositional layers
Crust: Average 7km for oceanic and Average 40km for continental. Basalt and silicates.
Mohorovičić discontinuity: seismic discontinuity at the base of the crust
Upper mantle: 40km -410km and consists of the lithospheric mantle and the plastic mantle
Asthenosphere: Made up of 60% Olivine and 40% Mg, Fe, Al and Ca silicates
Transition zone: 410 km-660km Olivine into denser wadyselite and garnet
Lower mantle: 660km No silicates, only Mg, Fe and Al oxides.
Rheological layers
The lithosphere includes the lithospheric mantle and lithospheric crust, both solid layers which will deform in a brittle nature at shallow depths and a ductile nature as the temperature rises and the rock weakens. The asthenosphere consists of 5% melt and will flow away from lithospheric stress making it a plastic material.
Figure 1: Layers of the earth
(Watson, 2009)