Short Answer 
Earthquakes are classified by depth into shallow (0-70 km) and deep (over 300 km), with shallow earthquakes linked to tectonic plate movements that can lead to mountain formation and surface damage. In contrast, deep earthquakes originate far below the surface, are less common, and do not influence mountain building or surface features, making their understanding key for risk assessment.
Understanding Earthquake Depth
The depth of an earthquake is classified based on where it occurs within the Earth’s layers. Earthquakes can be categorized into shallow (0 to 70 kilometers) and deep (greater than 300 kilometers) based on their depth. The location of the seismic focus, which is where the rupture happens, determines this classification. Understanding these depths helps in assessing the potential impact of the earthquake.
Shallow Earthquakes and Mountain Formation
Shallow earthquakes are closely associated with the movement of mountains, primarily arising from the convergence of tectonic plates. When plates collide, one can be forced under another in a process known as subduction, which can cause melting and uplift that forms mountains. This interaction typically results in shallow earthquakes that can have significant effects on the surface, leading to:
- Damage to human structures.
- Alterations in landscape and topography.
Deep Earthquakes and Their Impact
On the other hand, deep earthquakes occur at depths exceeding 300 kilometers within the descending slab of tectonic plates. These earthquakes are distinct as they originate far beneath the Earth’s surface and do not relate to mountain movement or formation. Consequently, they are less common and generally do not impact surface features or contribute directly to the process of mountain building. Understanding this distinction is crucial for evaluating earthquake risks.