Earthquakes and Plate Boundaries

• Vibrations in the ground resulting from breaks in the Earth's lithosphere are called earthquakes
• Earthquakes occur along plate boundaries

Plate Boundaries

• Divergent plate boundaries move away from each other
• Convergent plate boundaries move towards each other
• Transform plate boundaries slide past each other
• Deep earthquakes occur along convergent plate boundaries
• Subduction occurs when the oceanic plate sinks under a continental plate

Faults

• Faults have three main types: normal, reverse, and strike-slip
• Epicenter is the location on the Earth's surface directly above the focus
• Focus is where seismic waves originate
• Seismic waves are energy that travels as vibrations on and in Earth
• Energy is strongest near the epicenter

Seismic Waves

• Primary waves are also called P-waves
• Secondary waves are also called S-waves
• Particles move in a push-pull motion with primary waves
• Particles move at right angles to the direction of motion with seconday waves
• Surface waves particles move up and down in a rolling motion
• Primary waves are the fastest-moving seismic waves
• Surface waves move the slowest
• Primary waves are the first to be detected/recorded
• Secondary waves and surface waves are detected recorded after primary waves
• Primary waves travel through solids and liquids
• Secondary waves travel through solids only
• Surface waves travel only on Earth's surface closest to the epicenter
• Surface waves cause the most damage
• Seismologists use properties of seismic waves to map the Earth's interior
• A seismometer measures & records ground motion
• A seismograph is an instrument that records seismic waves
• A seismogram is a graphical illustration of seismic waves

Magnitude Scales

• The Richter Magnitude Scale is a measure of the amount of ground motion at a given distance from an earthquake
• The Moment Magnitude Scale measures rock movement along the fault relating to the total energy of the earthquake released
• The Modified Mercalli Scale measures the effects of an earthquake at a given location

The Solar System

• Planets, Dwarf Planets, Asteroids, and Comets orbit the sun, relfecting its light

Planets

• Planets orbit the sun
• Planets are nearly spherical
• Planets have a larger mass than the total mass of nearby objects

The Sun

• The center of the Solar System

Mercury

• The smallest planet, only slightly larger than Earth's Moon
• Very hot in the day but very cold at night
• No moons or rings
• Rotation period is 176 Earth days
• Revolution period is 88 Earth days

Venus

• Venus is nearly as big as Earth
• The hottest planet
• Includes mountains, valleys, and volcanoes
• No moons or rings
• Rotation period is 243 Earth days
• Revolution period is 225 Earth days

Earth

• The largest terrestrial planet
• Only known habitable planet
• Mostly covered in water
• Contains mountains, valleys, and volcanoes
• One moon
• Rotation period is 23.9 hours
• Revolution period is 365.25 Earth days

Mars

• One half the size of Earth
• Similar surface to Earth's dry land; appears red due to iron in rocks
• Thin atmosphere
• Two moons
• Rotation period is 24.6 hours
• Revolution period is 687 Earth days

Jupiter

• The largest planet
• Composed mostly of hydrogen and helium
• 95 moons with a ring system
• Notable Great Red Spot
• Rotation period is 9.9 hours
• Revolution period is 12 Earth years

Saturn

• Nine times wider than Earth is
• Composed mostly of hydrogen and helium
• Least dense planet
• 146 moons with a ring system
• Rotation period is 10.7 hours
• Revolution period is 29.4 Earth years

Uranus

• Four times wider than Earth is
• Mostly icy materials
• 28 moons and 13 rings
• Rotation period is 17 hours
• Revolution period is 84 Earth years

Neptune

• Four times wider than Earth is
• Composed of icy materials, hydrogen, and helium
• 16 moons and five principal rings
• Rotation period is 16 hours
• Revolution period is 165 Earth years

Pluto

• Pluto is no longer a planet because it has not cleared its orbit
• It should orbit the sun
• Have enough mass to draw itself into a round shape
• Have cleared all other celestial bodies, accept its moons, from its orbit