Earth Crust Stress

The Earth crust stress is the force that changes the size, shape and location of all the rocks that make up the Earth’s continental and oceanic crust. Although it consists of basalt and granite, the hardest rocks on Earth, the crust is continuously and relentlessly being altered by this powerful force. The stress at the surface of the Earth originates from the layers below the crust, rising from the depth in the upper mantle. Basically, there are three types of Earth crust stress: tension, compression, and shearing.

Tension

It is the geological force that stretches the crust apart. Over a period of millions of years, this action can shape the surface of the Earth into valleys and basins, which are well known geographical features. The Great Basin located between California and Utah is an example of a big depression in the surface of the planet that was formed by tension forces.

Compression

Also known as smashing, it is the force that pushes the crust together, crushing it until it folds or breaks. This compressing action gave shape to the planet’s mountain ranges. The Andes mountains were formed by smashing forces which folded the Earth’s crust, lifting geological materials to high altitudes.

Shearing

It is the force which pulls a large and extended layer of rock into opposite directions. This action causes a break or a change of shape. The shearing effect on the Earth’s crust can create large areas of raised and flat land; this geographical feature is called plateau. The Colorado Plateau is an example, which is a raised area of territory that covers Utah, Colorado, Arizona, and New Mexico.