Ch 3 - Our Fascinating Earth (3.5 - 3.10) Flashcards
Name the three broad categories of rock.
igneous
sedimentary
metamorphic
What are the individual substances that make up rocks?
minerals
What type of rock forms when molten rock solidifies?
igneous rocks
List the differences between extrusive and intrusive igneous rocks and give an example of each.
Extrusive - fine-grained rock formed when magma cools and hardens at the earth’s surface, eg obsidian, pumice, basalt
Intrusive - coarse-grained rock formed when magma cools and hardens while still underground, eg granite
Name the well-known igneous rock that contains quartz, feldspar, and mica.
granite
What do we call rock formed from sediments that have been pressed together?
sedimentary rock
What is a rough, crumbly rock sometimes used to make glass?
sandstone
What rock is formed from mud or clay and is often ground up and used to make bricks?
shale
What kind of rock is made from pebbles cemented together?
conglomerate
What is another name for rock salt?
halite
What soft, white rock is formed from the cemented skeletons of microscopic sea animals?
chalk or limestone
What do we call any trace left in a rock by a plant or animal?
fossil
What is the only stone formed by living animals?
reef limestone
What do we call an igneous or sedimentary rock that has been changed by extreme pressure or heat?
metamorphic rock
What weather-resistant, waterproof rock is formed by metamorphosis of shale?
slate
What is a beautiful rock that withstands weathering well and is commonly used for statues?
marble
What do we call the rarest, most durable and beautiful gems?
precious stones
Which gemstone is the hardest of all known minerals?
diamond
What do we call any rock containing a metal together with impurities?
ore
What do we call metals such as gold, silver, and platinum that are known for their durability, rarity, and beauty?
precious metals
What is the most commonly used metal?
iron/steel
What reddish-orange metal is a good conductor of electricity?
copper
What do we call the hard, shiny, black coal that is expensive to mine?
anthracite
What is the most common type of coal, also known as “soft coal”?
bituminous coal
What is the poorest quality coal, also known as “brown coal”?
lignite
What are two different ways of mining coal?
surface mining
underground mining
What do we call the thick, dark-coloured, flammable liquid that is considered a liquid fossil fuel?
petroleum or crude oil
Why is coal called a fossil fuel?
It is derived from the fossilized remains of plants.
How do oil geologists find buried petroleum?
Oil geologists use a variety of sensitive instruments to allow them to “see” the rock formations that lie deep beneath the surface. Engineers then drill holes into the most promising formations to see if they contain oil.
What do we call any hollow space in the earth’s crust that has formed naturally and is large enough for a person to enter?
a cave
What word means the study of caves?
speleology
In what kind of rock do solution caves usually form?
limestone
What is the basic mineral that makes up limestone?
calcium carbonate
What do we call animals that visit caves regularly but have to return to the surface to find food?
trogloxenes
Are solution caves formed mostly by chemical weathering or by physical weathering?
chemical weathering
Some caves have an abundance of green plants growing at or near the entrance. However, once you pass a certain point as you are entering a cave, green plants disappear. Why?
Green plants need sunlight in order to produce food by the process of photosynthesis. Once you arrive at the point where there is insufficient sunlight, green plants cannot live.
What do we call the area surrounding a magnet in which the force of magnetism affects other objects?
magnetic field
What do we call the places on a magnet (usually at the ends) where its magnetism is the strongest?
magnetic poles
What do we call a magnet that becomes magnetized only when it is hooked to a battery or some other source of electric current?
electromagnetic
What do we call the region of space affected by the earth’s magnetic field?
magnetosphere
What do we call the stream of harmful particles that flow constantly from the surface of the sun?
solar wind
