# What happens when a fault happens?

## What happens when a fault happens?

Earthquakes occur on faults. A fault is a thin zone of crushed rock separating blocks of the earth’s crust. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other. Faults can extend deep into the earth and may or may not extend up to the earth’s surface.

What is a fault a result of?

Normal faults result from tensional forces when rocks are displaced away from each other. Reverse faults results of compressional forces when rocks are displaced towards each other. Strike-slip or transform faults results from either compressional or extensional forces when rocks slip parallell to each other.

### What do faults do to rock layers?

Sudden motions along faults cause rocks to break and move suddenly, releasing the stored up stress energy to create an earthquake. A slip is the distance rocks move along a fault and can be up or down the fault plane. Slip is relative, because there is usually no way to know whether both sides moved or only one.

What is a fault and what causes it?

The places where movement occurs along the plate boundaries are called faults. Faults are the large cracks between plates, but not just any crack can be a fault, there has to be movement along at least one side of it. Tensional stress is when rock slabs are pulled apart from each other, causing normal faults.

#### What’s the main cause of most earthquakes?

Most faults in the Earth’s crust don’t move for a long time. But in some cases, the rock on either side of a fault slowly deforms over time due to tectonic forces. Earthquakes are usually caused when underground rock suddenly breaks and there is rapid motion along a fault.

What are the three types of fault?

There are three main types of fault which can cause earthquakes: normal, reverse (thrust) and strike-slip. Figure 1 shows the types of faults that can cause earthquakes. Figures 2 and 3 show the location of large earthquakes over the past few decades.

## What are the 3 fault types?

What is happening in normal fault?

Normal Faults: This is the most common type of fault. It forms when rock above an inclined fracture plane moves downward, sliding along the rock on the other side of the fracture. Normal faults are often found along divergent plate boundaries, such as under the ocean where new crust is forming.

### What are the 4 types of faults?

There are four types of faulting — normal, reverse, strike-slip, and oblique. A normal fault is one in which the rocks above the fault plane, or hanging wall, move down relative to the rocks below the fault plane, or footwall. A reverse fault is one in which the hanging wall moves up relative to the footwall.

How is a fault caused?

Faults are fractures in Earth’s crust where movement has occurred. Sometimes faults move when energy is released from a sudden slip of the rocks on either side. It forms when rock above an inclined fracture plane moves downward, sliding along the rock on the other side of the fracture.

#### Which city is most likely to experience a strong earthquake?

The following are the cities which experts believe are the most likely to experience a major earthquake.

• Manila, Philippines.
• Los Angeles, California.