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59 Cards in this Set
- Front
- Back
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How old is the earth? |
approximately 4.5 billion years |
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What are the two radioiostopes that are used to identify the Earth's age? |
uranium-238 potassium-40 |
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Briefly explain how Earth was formed |
rocks collided in space to form hot and bigger mass > formation of sun removed many rocks > less collisions, surface cooled, heat trapped inside |
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what is the purpose of Earth's magnetic field? |
To protect Earth from the sun's harmful cosmic rays |
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State 4 consequences if Earth's magnetic field isn't present |
Power outage Increased risk of cancer Some animals can't migrate Compass won't work |
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name 4 major components that make the structure of the Earth |
crust mantle outer core inner core |
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which structure of Earth is in liquid state? |
outer core |
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which structure of Earth is the cause of Earth's magnetic field? |
outer core |
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State the name of theory that describes the movement of continents |
continental drift |
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explain why the tectonic plates move |
crust which floats on top of mantle move along the flowing mantel |
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name 5 major tectonic plates on Earth |
Pacific Eurasian African North American South American |
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state what happens in terms of landscape if two continental plates meet together |
mountain ranges form |
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state what happens in terms of landscape if a continental plate and an oceanic plate meet together |
oceanic plate subducts under the continental plate |
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state what happens in terms of landscape if 2 tectonic plates move apart from each other |
new land forms |
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what are the 2 major functions provided by Earth's dynamic nature? |
Formation of new land Generation of magnetic field |
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name the gas that regulates global temperature |
carbon dioxide |
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name the organism in ocean, which is the major source of atmospheric CO2 removal |
plankton |
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state what happens to dead planktons |
sink down to the bottom of the ocean |
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state what type of volcano releases CO2 into the atmosphere |
subductive volcanoes |
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explain how subduction volcanoes can release large amounts of CO2 |
the magma it releases is from the tectonic plate with dead plankton that contains CO2 |
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name two types of natural disasters that occurs frequently at the tectonic plate boundaries |
Volcano Earthquake |
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what is a seismic wave |
wave of earthquake |
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what is the graph that measures seismic waves |
seismograph |
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what are the three major types of seismic waves? |
Primary Secondary Surface |
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which type of seismic waves is the fastest? |
primary wave |
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what type of seismic wave is the slowest? |
surface wave |
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what type of seismic wave arrives 2nd? |
secondary wave |
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what type of wave is the weakest? |
primary wave |
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what type of wave is the strongest? |
surface wave |
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name the scale that measures the magnitude of an earthquake |
richter scale |
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what magnitude of earthquake on Richter scale can most people feel? |
4 |
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how many seismic stations are required to locate the epicenter? |
3 |
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explain the difference between an epicentre and a focus |
Focus is the location of the origin of the earthquake Epicentre is the location of crust directly above the focus |
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what natural disaster occurs if an earthquake occurs under the sea? |
tsunami |
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what are molten rocks located under the crust is called? |
magma |
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what are the molten rocks located outside the crust called? |
lava |
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name the three major types of rocks |
Igneous rocks Sedimentary rocks Metamorphic rocks |
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what types of rocks form in and around volcanoes? |
igneous rocks |
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name the two types of igneous rocks |
Extrusive igneous rocks Intrusive igneous rocks |
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explain how extrusive igneous rocks are formed |
lava around volcanoes cool and form extrusive igneous rocks > they have small crystals due to the fast cooling time |
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explain how intrusive igneous rocks are formed? |
magma inside volcano cools and form intrusive igneous rocks > has large crystals due to its long cooling time |
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name two extrusive igneous rocks |
Pumice Basalt |
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name one intrusive igneous rock |
granite |
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state two uses of pumice |
Building material Scrubbing material |
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state one use of basalt |
material for asphalt road |
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state one use of granite |
flooring |
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explain how sedimentary rocks are formed |
rocks weather to form sediments, which is eroded from another place > eroded sediments pile up, layers of sediments compresses and hardens to form sedimentary rocks |
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what is sediment? |
small pieces of rock, stones and sand |
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define weathering |
breaking down of rocks into smaller pieces |
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define erosion |
transfer of sediments to a different location |
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name two sedimentary rocks |
sandstone limestone |
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state one use of limestone |
building material |
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state one general proerty of sedimentary rocks |
softer, less dense than other types of rocks |
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explain how sedimentary rocks are formed if the sediments are dissolved in water |
when water evaporates, the sediments appear and from sedimentary rocks |
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explain how metamorphic rocks are formed |
formed when other types of rocks are under high pressure and heat |
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name two metamorphic rocks |
Marble Stone |
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state one use of marble stones |
Building material Statue |
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state one use of slates |
roof tiles |
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list four requirements for a substance to be a mineral |
Naturally occuring Inorganic solid Definite chemical composition Ordered atomic arrangement |
