Under the ground, the earth consists of large tectonic plates that shift around over time. If two of these plates meet at any point, extreme pressure is created which sometimes forces one or both of the plates upwards over time. It results in the creation of mountains and cliffs. However, the most violent episodes of tectonic activity can result in earthquakes, which can create tears in the earth and form cliffs. Major sedimentary rocks that form a cliff are dolomite, sandstone, and limestone.
Some types of igneous rocks which form cliffs include granite and basalt. Major processes involved in the formation of a cliff are discussed below. At least, one point of weakness is created when waves from the sea hit the land leading to a cut known as a Notch.
This Notch formed erodes further to develop a cave. The cave develops hollows along the land leading to a mass of hard rock. As time goes, more erosion from weathering takes place making the overhanging hard part of the cave to collapse into the sea. Sea water washes away the fallen part leading to the formation of a cliff. A continuous erosion and weathering cause the cliff to enlarge and retreat more into the land while continuous lapping of water against the adjacent rocks leads to the formation of a vertically cut feature.
After several thousands of years, only the very hard rocks are left standing, either vertically or sloping. This process leads to the formation of both huge and small cliffs. In some instances, cliffs are also formed along a river. In this case, as the river water flows with velocity, the water begins cutting the earth.
When the water level gets higher during the rainy season, the speed of water increases. This leads to an expansion of the cliff. Although the process took place a long time ago, it is believed that some cliffs were formed from glaciers. It is also believed that during the ice age, mammoth glaciers covered the earth. Due to global warming, the glacier began moving across the earth. Because of the great weight and velocity of glaciers, it formed some depressions as it flowed across the globe.
Expanse cliffs were therefore created since glaciers have tremendous weight. These types of cliffs are scattered with rock outcroppings as the main feature. In fact, glaciers lead to the formation of triangularly shaped cliffs which are broad hence known as truncated spurs.
The plates shift from time to time. When the two plates come into contact with each other, huge pressure is created forcing one of the plates to move upwards and protrude.
Although the process may take time, mountains and cliffs are created. Escarpments are common types of cliffs that arise out of the movement of a geologic fault or occurrence of a landslide.
Since rocks have varying degrees of hardness, which makes some rocks become incompatible leading to differential erosion of the layers. The erosion leads to the formation of a cliff. Over time, wearing-off occurs through agents such as water or wind leading to one side being more eroded than the other. The coastal cliffs can also be classified as steep escarpments that form when the sea levels rise. A complex volcano in the middle of Taal Lake and is often called an island within a lake, that is an island within a lake that is on an island as well as one of the lowest volcano in the […].
Mayon Volcano is one of the active volcanoes in the Philippines. According to local folklore, the volcano was named after Daragang […]. Together with the atmosphere and the rotation of the earth on its axis. The earth on which weather moves on has its own effect on the weather. The different landforms like mountains, volcanoes, plains, and the […]. Submit Landform Pictures Login. Toggle navigation. Submit Your Own Landforms We want pictures and location of the lanforms around the world and we need your help.
Today's Featured Picture. The Albers projection is a conic, equal area map projection, named after Heinrich C. Landform Blog. Taal Volcano Taal Volcano is the second most active volcano found in the province of Batangas. Mayon Volcano Mayon Volcano is one of the active volcanoes in the Philippines.
Erosion is the process where rocks are broken down by natural forces such as wind or water. There are two main types of erosion: chemical and physical. In physical erosion, the rock breaks down but its chemical composition remains the same, such as during a landslide or bioerosion, when plants take root and crack rocks.
Explore the process of erosion with this collection of resources. Weathering is the process of the weakening and breakdown of rocks, metals, and manmade objects. There are two main types of weathering: chemical and physical. An example of chemical weathering is acid rain.
Caused mostly by the burning of fossil fuels, acid rain is a form of precipitation with high levels of sulfuric acid, which can cause erosion in the materials in which it comes in contact. An example of physical weathering is wind blowing across the desert playas. This process causes rocks to form a specific pyramid-like shape and they are called ventifacts.
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Encyclopedic Entry Vocabulary. A cliff is a mass of rock that rises very high and is almost vertical , or straight up-and-down. Cliffs are very common landscape features. They can form near the ocean sea cliffs , high in mountains, or as the walls of canyon s and valley s. Waterfall s tumble over cliffs. Cliffs are usually formed because of processes called erosion and weathering. Weathering happens when natural events, like wind or rain, break up pieces of rock. In coast al areas, strong winds and powerful waves break off soft or grainy rocks from hardier rocks.
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