The main source of geological information :-
Rocks on the surface of the Earth & found the mining, volcanic ejaculatory, seismic waves, high temperature & pressure under the surface of the Earth & meteor ashy are main source of geological information.
- Temperature pressure & density increases towards the inside of the surface of the Earth. Average increase in temperature is 1°c if we go 32 meter to the inner side of the surface of Earth.
- On the basis of Scientific evidence obtained from the above mentioned sources, internal construction of the Earth is divided into three layers.
Crust :-
- The outer most part of the solid Earth is known as the Crust.
- It's average thickness under the oceans is 5 km and it is up to 30 km under the continents.
- The cliffs (rocks) of the continents crust are formed from the granite and the cliffs of oceans crust are formed from basalt.
- The upper layer of the crust is formed from the sedimentary rocks, in which the sufficient of alumjalu and silica is formed more.
Mantle :-
- It is found at the deapth of 2900 km. Under the Crust.
- The upper liquid part of Mantle is called the Asthenosphere, which is the main source of Volcanic ejaculatory.
- The solid part of Mantl & Crust both together are called the Lithosphere.
- The uneven later between the Mantle & the Crust is called the Mohorovicic or the Mohoirrelevance. Their density is 3.4 gram/cm³, Which is more than the density of the Crust, which is 3.4 gram/cm³.
Core :-
- This layer is found below the Mantle up to the depth of 2900-6371 Km.
- It is formed from the heavy matters like nicke & iron.
- So it is also known as the 'NiFe' layer.
- It's density is the highest.
- 98% of the crust is made of eight element like oxygen, silicone, aluminum, iron, calcium, sodium, potassium and mangasese.
Stones or Rocks :-
- A branch of science related to study about rocks is called the Pertology. Formation of rocks occurs with one or more minerals together. There are the types of rocks according to their formation.
- Igneous, rocks :- formed from magma & lava e.g. granite, basalt, gabbros, pegmattite etc.
- Sedimentary Rocks :- formed from the deposition of sediments. Fossile & coal & petroleum are found in the Sedimentary Rocks, e.g. lime stone, sand stones, coal, talc or chalk, Tor, Kanglormet etc.
- Metamorphic rocks :- They found due to change in sedimentary and igenous rocks because of chemical process and change in their temperature, pressure.
Earthquake (Seismic) :-
- It is a contingent internal process which is a result of so many geological processes, which creates the imbalance.
- P- primary, S- secondary and L- long waves are generated during the Earthquake.
- Seismic waves spread across the horizon in all directions.
- The origin point of the Earthquake under the Earth's layer is called the focus point of Earthquake. The point exactly above the focus point of Earthquake, on the Earth''s layer is called the Epicenter of Earthquake.
