## Why are earthquakes most common around the Pacific Ocean?

Over 80 per cent of large earthquakes occur around the edges of the Pacific Ocean, an area known as the ‘Ring of Fire’; this where the Pacific plate is being subducted beneath the surrounding plates. The Ring of Fire is the most seismically and volcanically active zone in the world.

## Where do most earthquakes occur along?

Most earthquakes occur along the edge of the oceanic and continental plates. The earth’s crust (the outer layer of the planet) is made up of several pieces, called plates. The plates under the oceans are called oceanic plates and the rest are continental plates.

## Do earthquakes occur everywhere along the seafloor?

Earthquakes occur everywhere – so, at least, it seems. Temblors happen on all continents and beneath the deep oceans. They shake the world’s highest mountains, the Himalayas, and the Earth’s deepest valley, the Dead Sea.

## Where do most earthquakes occur near mid ocean ridges?

Many earthquakes occur along the axis of the mid-ocean ridge, where spreading and slip along normal faults downdrop blocks along the narrow rift.

## Are there many earthquakes near mid-ocean ridges?

Mid-ocean ridges and transform margins have shallow earthquakes (usually less than 30 km deep), in narrow bands close to plate margins. Subduction zones have earthquakes at a range of depths, including some more than 700 km deep. Figure 12.16 Earthquakes greater than magnitude 5, from 2000 to 2008.

## What are 2 types of body waves?

Body waves are of two types: Primary waves (also called P-waves, or pressure waves) and Secondary waves (S-waves, or shear waves).

## What are 4 types of waves?

Types of Waves in Physics

• Mechanical waves.
• Electromagnetic waves.
• Matter waves.

## What are P and S waves?

P-waves are compression waves that apply a force in the direction of propagation. On the other hand, S-waves are shear waves, which means that the motion of the medium is perpendicular to the direction of propagation of the wave. The energy is thus less easily transmitted through the medium, and S-waves are slower.

Surface waves

## What waves are detected first?

The first kind of body wave is the P wave or primary wave. This is the fastest kind of seismic wave, and, consequently, the first to ‘arrive’ at a seismic station. The P wave can move through solid rock and fluids, like water or the liquid layers of the earth.

## What are the 7 electromagnetic waves in order?

In order from highest to lowest energy, the sections of the EM spectrum are named: gamma rays, X-rays, ultraviolet radiation, visible light, infrared radiation, and radio waves. Microwaves (like the ones used in microwave ovens) are a subsection of the radio wave segment of the EM spectrum.

## Which earthquake waves are the fastest?

P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.

## What are the 3 types of waves in an earthquake?

There are three major kinds of seismic waves: P, S, and surface waves. P and S waves together are sometimes called body waves because they can travel through the body of the earth, and are not trapped near the surface. A P wave is a sound wave traveling through rock.

mantle

## Which set of waves are the P-waves?

A P wave, or compressional wave, is a seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.

## What does the P wave stand for?

atrial depolarization

## What are the 2 subtypes of P waves?

Body waves are of two types: compressional or primary (P) waves and shear or secondary (S) waves. P- and S- waves are called “body waves” because they can travel through the interior of a body such as the Earth’s inner layers, from the focus of an earthquake to distant points on the surface.

## How do P waves travel?

P waves travel through rock the same way that sound waves do through air. That is, they move as pressure waves. When a pressure wave passes a certain point, the material it is passing through moves forward, then back, along the same path that the wave is traveling. P waves can travel through solids, liquids and gases.

## What happens during the P wave?

The P wave indicates atrial depolarization. The P wave occurs when the sinus node, also known as the sinoatrial node, creates an action potential that depolarizes the atria. The P wave should be upright in lead II if the action potential is originating from the SA node.

## What do P waves feel like?

The waves also travel through the Earth at different speeds. The fastest wave, called the βPβ (primary) wave, arrives first and it usually registers a sharp jolt. βIt feels more abrupt, but it attenuates very quickly, so if you are far away you often won’t feel the P wave.β

## What is the difference between P waves and S waves?

P waves travel at speeds between 1 and 14 km per second, while S waves travel significantly slower, between 1 and 8 km per second. The S waves are the second wave to reach a seismic station measuring a disturbance. The difference in arrival times helps geologists determine the location of the earthquake.

## What does an earthquake feel like from far away?

A large earthquake far away will feel like a gentle bump followed several seconds later by stronger rolling shaking that may feel like sharp shaking for a little while. A small earthquake nearby will feel like a small sharp jolt followed by a few stronger sharp shakes that pass quickly.

## Is a magnitude 12 earthquake possible?

The magnitude scale is open-ended, meaning that scientists have not put a limit on how large an earthquake could be, but there is a limit just from the size of the earth. A magnitude 12 earthquake would require a fault larger than the earth itself.