Unit 1 Flashcards
(27 cards)
What are P-waves?
Also called seismic waves or primary waves, they are aftershock waves from an earthquake
What are the four layers of the earth from the centre to the surface?
Inner core, outer core(core), mantle and crust
How old is our Earth?
4.6 billion years old
What are earthquakes?
Tremblings or vibrations of the ground, caused by the sudden release of built up energy in the Earth’s crust
How thick is each?
Crust is the thinnest, mantle the thickest and core is in the middle of thick and thin
What is the focus?
First place that rocks break below the surface in an earthquake
What is each layer made of?
Crust-loose materials like rocks,soil and seabed
Mantle-hard rock, then super-heated molten rock, then rock again
Outer Core-iron and nickel
Inner Core-solid ball of iron and other minerals
What is the epicenter?
Point right above(above or on the surface) the focus
What are the layers of the Earth from the surface to the center?
Crust,mantle,outer core,inner core
What is the Richter Scale?
Scale developed by Charles Richter and it measure the magnitude(degree)of an earthquake
What are S-waves?
Also called, secondary wave or shear wave, they are waves that move through the ground(solids),but unlike seismic waves, they can’t go through liquids
Where are most earthquakes located and why?
On the edge of tectonic plates because they are constantly moving and that creates movement in the Earth’s crust
What is the difference between magma and lava?
Magma is molten rock still inside the volcanoe, while lava is molten rock that is outside the volcanoe
What are volcanoes?
Opening in earth’s crust through which solid and molten rock, ash and gases escape
What is erosion?
Process that moves soil from one place to another
What causes Earthquakes?
Folds and faults in the ground
Tectonic plates moving
What is a bedrock?
Layer of solid rock beneath the loose rock fragments
What is a seismograph?
Device that detects the waves of energy that spread through the earth from the focus if an earthquake
Which arrive first, S-waves or P-waves?
P-waves and they travel faster
What is a seismogram?
The printout of a seismograph
What is weathering?
Process that wears down rocks and other objects by water, glacial ice, wind and waves
Types are mechanical, chemical, biological
What is the difference between weathering and erosion?
Erosion-soil
Weathering-break down
What is deposition?
Eroded materials being added to landforms and landmass
What is sedimentation?
Process of the sediments being deposited onto landforms and land masses
