- he Earth can be divided into one of two ways: mechanically or chemically.
- Mechanically (or rheologically) meaning the study of liquid states – it can be divided into the lithosphere, asthenosphere, mesospheric mantle, outer core, and the inner core.
- But chemically or by composition, which is the more popular of the two, it can be divided into the crust, the mantle (which can be subdivided into the upper and lower mantle), and the core – which can also be subdivided into the outer core, and inner core.
Sources to study the earth’s interior
The sources which provide knowledge about the interior of the earth may be classified into 2 sources-
- Direct sources
- Surface rock
- Volcanos
- Mining Projects
- Drilling Projects
- Deep Ocean Drilling Project
- Integrated Ocean Drilling Project
- Indirect sources
- Temperature and pressure variation
- Seismic activities
- Meteorites
- Gravitation
- Magnetic field
Direct Sources of Earth’s Interior
These materials are available normally at the surface of the earth and are sourced from:
- Earth’s Surface: Surface rock is readily available at the surface of the earth. By observing these rocks, we can know the form of material that can be found up to a certain depth.
- Volcanoes: Volcanic material that gets out after an eruption is readily available to us for observation. Since these materials come up from great depth, therefore, the quality of this material at great depth can be analyzed directly. However, the accurate depth of material can’t be ascertained.
- Material obtained from Mining and Drilling areas: From Mining and Drilling areas, many materials can be sourced for analysis. These materials reveal the nature of material available at a certain depth. From mining, it is easy to deduce that pressure and temperature increase from the surface towards the interior deeper depth. Also, the Density of the material increases from the top surface to the interior bottom.