ESSE 3020 Lecture Notes - Continental Drift, Isostasy, Seismic Wave
Document Summary
The earth is made up of two parts-the interior structure that lies beneath the crust, and the outer surface that can be seen in the form of oceans and continents. The interior structure of the earth is responsible for many of its geophysical properties. Earth"s interior structure has been determined by observing the travel time of seismic waves when there is an earthquake. Figure 1 shows a schematic diagram of earth"s interior structure. As observable from figure 1, the outermost ring is the earth"s crust, also known as the lithosphere. Directly below that is the upper mantle, followed by the lower mantle, then the liquid outer core and then the solid inner core. The solid inner core is an iron-nickel alloy, and it is responsible for the earth"s magnetic field. Table 1 summarizes the properties of each of the components in the earth"s interior structure.