Earth and Beyond (Assignment 2) Flashcards
What is the SIZE of the EARTH?
12 756 km
What is the diameter from pole to pole (north pole to south pole)?
12 720 km
Name the layers of the earth
- outer core
- mantle
- inner core
- crust
Which layer is the THICKEST?
Core
Explain the INNER core
Solid
As hot as the surface of the sun
Explain the OUTER core
Liquid
Consists mainly of iron and nickel
Explain the mantle
Mostly rocks
Becomes softer the deeper they go
Consists of NON-METALS - Silicon and oxygen
METAL - Magnesium
Explain the CRUST
Thin shell consists of VOLCANIC rocks
Thickness varies: 8km on the ocean floor
50km on the continents
What does the word LITOSPHERE mean?
Sphere of rocks
What are the layers of the LITOSPHERE?
= Solid rock in the outer most part of the mantle
= thin, rocky crust covers the land and seabed
= soil covers the land and seabed
Name the 3 types of rock in the Earth’s crust
1) Igneous
2) Sedimentary
3) Metamorphic
IGNEOUS rock - how does it form?
Magma cools down and solidifies
Give some examples of IGNEOUS rock
Granite
Basalt
Pumice stone
What is IGNEOUS rock (example: granite/basalt/pumice stone) used for?
Grante - grave headstones & kitchen surfaces
Pumice stone - as sponges in bathrooms
SEDIMENTARY rock - how is it formed?
Layers
of
sand,
silt
and clay
(squeezed together over a
very long time)
Give some examples of SEDIMENTARY rock
Sandstone
Shale
Limestone
What are the uses of SEDIMENTARY rock?
(For example: sandstone; shale; limestone)
Sandstone - construction of building
Limestone - used in cement manufacturing
and smelting
What is silt?
VERY FINE particles, finer than sand but coarser than clay
What is smelting?
Heating an ORE to extract the metal it contains
How is METAMORPHIC ROCK formed?
Igneous OR Sedimentary rock are HEATED DEEP UNDERGROUND for a long time
Give a few examples of METAMORPHIC ROCK type
Marble
Slate
What is METAMORPHIC ROCK (example: Marble ; Slate) used for?
Used for statues; floor and roof tiles
Imagine a church which is buildt with sandstone walls. What TYPE of rock is sandstone?
Sedimentary rock
What is LAVA?
Magma that flows out unto the earth’s surface
What do you call the scientific study of the structure and composition of the earth, especially the rocks?
Geology
What do you call a person who studies rocks?
Geologist
Explain the ROCK CYCLE step by step
- MOLTEN rock from the mantle (magma) pushes up
- Pools of MAGMA cool down slowly in the crust to
form igneous rock (granite) - Some magma escapes to the surface (now called
LAVA) as a volcano - This magma cools down quickly to form igneous
rock (pumice stone) - Rocks on the surface of the earth are
WEATHERED (heat;cold;wind;water) to form
smaller particles - Wind & water transport PARTICLES to plains and
the sea by erosion - Particles are laid down as SEDIMENT
- Sediment is covered by more layers
- Pressure of many layers turns the lower layer into
SEDIMENTARY rock (like sandstone) - Hot magma heats the surrounding rock and
changes its chemical structure to form
METAMORPHIC rock (like slate) - Some stones are pushed below the crust, melts
and becomes magma again
Name the factors responsible for the WEATHERING of rocks
Heat
Cold
Wind
Water