The geomorphology is a speciality of the geology: it study the relief. It doesn't study only the name and the shape. It also try to know how and why that relief was made.
The landscape is the aspect of land relief.
The relief is the set of landforms which can be seen on Earth's surface. Is a changing element, the result of the internal processes, that raise it, and the result of the external processes, that model it.
But many people didn't believe this, and in the XVIII-XIX centuries appeared two theories:
- Catastrophic theory: It was proposed by Cuvier, a French biologist and paleontologist. He thought that all the mountain ranges and other landforms were made because of major disasters, not by the passage of time. An example of major disaster is the universal deluge.
- Gradualism theory: This theory is contrary to the catastrophic theoriy. Proposed by Lyell, an English lawyer and biologist, it said that this process is due to continuous changes. That means it need lots of year to have a big change.
The texture is how materials are disposed, the physical appearance.
The structure is the position of the rocks in the surface, the layers that form them... It also means the position in which you find them.
Factors that control the modelling of the relief:
- Climate: Controls the agents and the vegetation cover. The absence of vegetation cover favour rocks weathering and erosion in the ground. Within the climate, is include the temperature, the rainfall, the pressure and the wind.
- Lithology: To the same agent, to rocks can be modelled in different ways: in the rocks form in layers, the result depends on the disposition.
- Structure: Is how the rocks are located.
- Human being: It's an influential factor. It can change the relief directly (building), or indirectly (removing the vegetation cover).
All that process need an energy source to be able to produce. That energy comes from:
- The gravitational force which we can calculate with the law of the universal gravitation.
- The solar radiation.
- The internal heat of the Earth.
- The forces of attraction that causes the sun and the moon on the Earth.
