DIASTROPHISM
Diastrophism is the process which involves movements of the
earth’s crust such that a portion is pushed up, pushed down or forced sideways.
Theories on what causes diastrophism
1. Theory if Isostasy maintains that the continents, mountains, plain and ocean basins are in a balanced state. Any changes in any of the components of the earth’s crust affects the balance and therefore, the other components must also adjust.
2. Contraction Theory states that the earth is slowly shrinking, which is caused either by lowering its temperature or the squeezing of its parts into smaller volume by great pressure.
3. Convection Theory maintains that a powerful convection currents may occur in the earth’s crust causing the flow of, materials from underneath upward and the sinking of heavier materials.
4. Continental Drift Theory states that originally, the earth was composed of only one continent. Due to the movements of material under the earth’s crust, the continent was divided.
EARTHQUAKE
Earthquake is the shaking of
the earth’s surface as a result of the sudden release of stresses built up in
the earth’s crust
Seismology is the branch of
science that deals with earthquakes.