EARTHQUAKE (Types of Seismic Waves, Earthquake Terminologies, and 4 Basic Types of Fault)

Summary

This script discusses the science behind earthquakes, explaining the term 'very quick earthquake' as a sudden slip on a fault and the resulting ground shaking. It delves into the types of seismic waves, including body waves (P and S waves) and surface waves (Love and Rayleigh waves), detailing their characteristics and how they cause damage. The script also covers earthquake terminology like hypocenter, epicenter, fault plane, and magnitude, and touches on the different types of faults, such as strike-slip, dip-slip, and oblique faults.

Takeaways

• 🌟 A very quick earthquake refers to a sudden slip on a fault, resulting in ground shaking and seismic energy release.
• 📊 A seismogram is a record made by a seismograph in response to ground motions caused by earthquakes or other sources.
• 🌀 There are different types of seismic waves: body waves (P and S waves) and surface waves (Love and Rayleigh waves), each with distinct characteristics.
• 🏃‍♂️ P-waves, or primary waves, are the fastest and can travel through solid rock and some liquids, causing a pushing and pulling motion.
• 🔄 S-waves, or secondary waves, are slower and can only travel through solids, moving particles up and down or side to side.
• 🌐 Surface waves cause the most damage during an earthquake and have a lower frequency than body waves.
• 🔺 Love waves are the fastest surface waves, moving horizontally side-to-side, confined to the Earth's surface.
• 🌊 Rayleigh waves move the ground in a rolling motion similar to waves on water, causing significant shaking during an earthquake.
• 📍 The hypocenter is the point within the Earth where an earthquake starts, while the epicenter is the point on the surface directly above it.
• ⛓ Faults are fractures where earthquakes occur, with different types including strike-slip, dip-slip, and oblique-slip faults.
• 📈 Earthquake magnitude is a measure of the relative size of an earthquake, indicating the amount of energy released.

Q & A

What is a very quick earthquake?

A very quick earthquake refers to a sudden slip on a fault, resulting ground shaking, and related seismic energy. It can also be a close relative of volcanic or magmatic activity or other sudden stress changes in the ground.

What is a seismogram?

A seismogram is a record written by a seismograph in response to ground motions produced by earthquakes, explosions, or other ground motion sources.

What are the two main types of seismic waves?

The two main types of seismic waves are body waves and surface waves. Body waves travel through the interior of the Earth, while surface waves travel along the Earth's surface.

What are the subcategories of body waves?

Body waves have two subcategories: P-waves (primary waves) and S-waves (secondary waves).

How do P-waves differ from S-waves?

P-waves are the fastest and can move through solid rock and liquids, while S-waves are slower and can only move through solid rock. P-waves push and pull the rock they move through, similar to sound waves in air.

What are surface waves and why are they significant?

Surface waves travel across the Earth's surface and have a lower frequency than body waves. They are significant because they are responsible for most of the damage and destruction caused by an earthquake.

What are the two types of surface waves?

The two types of surface waves are Love waves and Rayleigh waves.

How do Love waves move the ground?

Love waves move the ground in a side-to-side motion, confined to the surface of the Earth.

What is the characteristic movement of Rayleigh waves?

Rayleigh waves move the ground up and down and side-to-side in the same direction that the wave is moving, similar to how wind blows across a lake or ocean.

What is the hypocenter of an earthquake?

The hypocenter is the point within the Earth where an earthquake rupture starts.

What is the difference between an earthquake's hypocenter and epicenter?

The hypocenter is the point within the Earth where the earthquake starts, while the epicenter is the point on the Earth's surface vertically above the hypocenter.

What are the four basic types of faults?

The four basic types of faults are strike-slip faults, dip-slip faults, reverse faults, and oblique-slip faults.

How do strike-slip faults differ from dip-slip faults?

Strike-slip faults involve mostly horizontal movement, whereas dip-slip faults involve vertical movement, with the rock mass above the fault moving up or down.