Earthquakes and Fault Types

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Questions and Answers

What phenomenon causes earthquakes as described in the content?

Movement of the Earth's crust due to wind

The alignment of stars in the solar system

Tsunami waves originating from volcanic activity

Intense shaking of the Earth's surface due to stress and energy release (correct)

Which type of fault results from pulled apart rocks due to tension?

Normal Fault (correct)

Reverse Fault

Strike-slip Fault

Thrust Fault

Which type of seismic wave is described as the fastest and the first to arrive at a seismograph?

S Waves

Rayleigh Waves

Primary (P) Waves (correct)

Surface Waves

What characterizes a reverse fault?

Hanging wall moves up while foot wall moves down Signup and view all the answers

What defines active faults?

Structures that produce shallow earthquakes Signup and view all the answers

What happens to S Waves when they encounter liquid layers of the Earth?

They stop traveling Signup and view all the answers

Which of the following describes a strike-slip fault?

Horizontal movements with one side shifting left or right Signup and view all the answers

What is a fault scarp?

A feature created by change in land elevation across a fault Signup and view all the answers

What is a significant characteristic of comets when they approach the Sun?

They generate a glowing trail from sublimation. Signup and view all the answers

Which of the following planets has a thick atmosphere primarily composed of carbon dioxide?

Venus Signup and view all the answers

What is the primary reason Mars is referred to as the 'Red Planet'?

The iron oxide present on its surface. Signup and view all the answers

Which planet is recognized for its stunning ring system?

Saturn Signup and view all the answers

What distinguishes Neptune among the planets in our solar system?

It has the fastest winds in the solar system. Signup and view all the answers

Which of the following planets is known to support life?

Earth Signup and view all the answers

Which planet has a day that is longer than its year?

Venus Signup and view all the answers

What unique feature does Uranus possess concerning its axis?

It has a significantly tilted axis causing extreme seasons. Signup and view all the answers

What type of wave is characterized by horizontal movement of the ground and is confined to the Earth's crust?

Love Waves Signup and view all the answers

Which scale is used to measure the magnitude of smaller earthquakes?

Richter Scale Signup and view all the answers

What is required for a tropical cyclone to form?

Sea surface temperature of 27°C or higher Signup and view all the answers

Which of the following correctly describes the movement of Rayleigh waves?

Rotates ground horizontally and vertically in the direction of the wave Signup and view all the answers

What characterizes a tropical storm according to wind speed?

Winds of 34 knots or higher Signup and view all the answers

What is a significant effect of a cold front entering a typhoon?

It can change the typhoon's strength or structure Signup and view all the answers

Which component is essential in calculating earthquake moment?

Distance the fault moved Signup and view all the answers

How is a meteor different from a meteorite?

A meteor is the streak of light in the atmosphere; a meteorite is the object itself. Signup and view all the answers

What happens when a tropical cyclone moves over cooler waters?

It undergoes dissipation Signup and view all the answers

What is the main cause of numerous thunderstorms during a monsoon?

Seasonal heavy rains and low pressure Signup and view all the answers

What does a low-pressure area indicate?

Rising warm air and decreased air pressure Signup and view all the answers

What meteorological phenomenon occurs when warm moist air interacts with cool air?

Thunderstorm development Signup and view all the answers

What is a characteristic feature of the 'eye' of a tropical cyclone?

The calm center surrounded by stormy eyewall Signup and view all the answers

What is the significance of the Intertropical Convergence Zone (ITCZ)?

It is where trade winds converge, fostering frequent storms Signup and view all the answers

Study Notes

Earthquakes

Earthquakes are intense ground shaking caused by energy release from movements in Earth's outer layer.
Stress: A push or pull on the Earth's crust, causing gradual changes in the shape and volume of rocks.
Fault: A surface where rocks break or tear apart due to stress, creating a zone of weakness. A fault scarp is an elevation change across the fault; the fault plane is the surface of movement.
Fault Blocks: A faulted rock has two blocks, the hanging wall (above the fault) and the foot wall (below the fault).
Fault Types:
- Normal Faults: Rocks pull apart (tension), hanging wall moves down, foot wall moves up.
- Reverse Faults: Rocks squeeze together (compression), hanging wall moves up, foot wall moves down.
- Thrust Faults: A type of reverse fault with hanging wall sliding over the footwall, often creating mountains.
- Strike-Slip Faults: Horizontal movement of rocks (left or right), one side moves relative to the other.
Active vs. Inactive Faults: Active faults have displacement, producing shallow earthquakes. Inactive faults can rupture again if stress increases.
Seismic Waves: Waves of energy created by rock breaking.
- Body Waves: Travel through Earth's interior.
  - P-waves (Primary): Fastest, first to arrive, particles move in same direction as the wave.
  - S-waves (Secondary): Slower, travel only through solids, stop at liquid layers, particles move perpendicular to wave direction.
- Surface Waves: Travel along Earth's surface.
  - Love Waves: Horizontal ground movement (side-to-side), limited to the crust.
  - Rayleigh Waves: Roll-like ground movement (up and down and side-to-side), cause most surface shaking.
Magnitude: A measure of energy released at the earthquake source.
- It is not affected by distance.
- Measured using the Richter scale (scaled 1-10). Higher numbers indicate more energy released
- Moment Magnitude Scale (MW): Used for a wider range of earthquake sizes, particularly large ones.
- Richter Scale: Used for smaller magnitude earthquakes.
Moment: A product of the fault's movement and the force needed to move it: M = d x f (M = Moment, d = distance, f = force)
Plate Tectonics: Large slabs of Earth's lithosphere move slowly, interacting and deforming rocks. Plate movement explains fault motion.

Typhoons

A typhoon is a tropical storm with maximum sustained winds of 34 knots or higher. (A similar storm in other regions is called a hurricane.)
Weather: The state of the atmosphere (e.g., sunny, rainy, windy).
Wind: Movement of air. Measured in KPH.
Pressure: Force of air's weight, crucial for weather patterns and storms.
Rain: Moisture falling from condensed water vapor.
Thunderstorms: Storms with lightning, thunder, and heavy rain.
Storm Surge: Abnormal increase in sea level due to storms, causing coastal flooding
Sky/Cloud Cover: Percentage of sky covered by clouds.
Landfall: Storm crossing onto land.
Monsoon: Seasonal heavy rain, sometimes a developing storm.
Ocean Heat Content (OHC): Total heat energy in the ocean; warmer oceans fuel tropical storms
Intertropical Convergence Zone (ITCZ): Low pressure zone near the equator where trade winds meet, causing frequent storms.
Low-Pressure Area (LPA): Region with lower air pressure than surroundings, usually associated with storms.
Typhoon Track: The path a typhoon takes.
Tropical cyclone: A large storm over warm ocean water, including hurricanes and typhoons
Tropical Disturbance: A cluster of thunderstorms, potentially developing into a tropical cyclone
Tropical Depression: A tropical cyclone with sustained winds less than 38 mph (33 knots).
Tropical Storm: An organized cyclone with winds stronger than a depression.
Conditions for Typhoon Formation
- Sea surface temperature of 27°C or higher.
- A low-pressure system.
- Air converging and rising to form storm clouds.
The "Eye" of a Storm: Calm center created by sinking air in the eye while rising air is in the eyewall
Weakening Typhoons
- Move over cooler water, encounter strong upper-level winds, make landfall, lose ocean energy
Fronts: Boundaries between air masses, influencing typhoons.
- Warm Front: Warm, moist air meets cooler air, causes clouds and rain.
- Cold Front: Cooler, denser air pushes into the storm, changing strength or structure.

Solar System

Meteor: A space object burning up in Earth's atmosphere (appears as a shooting star), not a star. Usually caused by debris.
Meteor Showers: Occur when Earth passes through comet or asteroid debris.
Asteroid: A small, rocky or metallic object orbiting the Sun (often > 1 meter in size).
Comets: Small, icy, dusty objects orbiting the Sun, ice sublimating when near the Sun, creates a glowing trail (mostly far beyond Neptune).
Key Differences: Asteroids are solid, comets leave trails of gas and dust.

Planets of the Solar System

Mercury: Closest to the Sun, extreme temperature variations, no atmosphere.
Venus: "Earth's sister planet" similar size but thick CO2 atmosphere, extreme greenhouse effect, melting temperatures.
Earth: Supports life, breathable atmosphere, liquid water, diverse ecosystems.
Mars: "Red Planet" due to iron oxide, largest volcano and canyon, potential for past life, future exploration.
Jupiter: Largest planet, Great Red Spot (massive storm), strong magnetic field, many moons.
Saturn: Famous rings of ice and rock particles, primarily hydrogen and helium, many moons (Titan is notable).
Uranus: Tilted axis, extreme seasonal changes, blue-green color due to methane, an "ice giant" (water, ammonia, methane ice).
Neptune: Farthest planet, deep blue color due to methane, strong winds, large moon Triton (orbiting opposite to Neptune's rotation).

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Description

Explore the dynamics of earthquakes and the various types of faults that contribute to ground shaking. This quiz covers key concepts such as stress, fault blocks, and different fault types, including normal, reverse, thrust, and strike-slip faults. Test your understanding of how these geological features affect the Earth's crust.