Rocks Flashcards
What is the approximate diameter of the Earth?
12,000 km
What is the name of the outer layer of the Earth?
The crust
What is the approximate depth of the Earth’s outer layer (Crust)?
10 - 70 km
What is being described here:
Below the Earth’s crust is a layer of rock that makes up 80% of the planet’s volume, it flows slowly like liquid.
Mantle
What is the approximate temperature of the partially melted mantle
3000 ‘c
What is the centre of the Earth called?
The core
What is the centre of the Earth made of?
metals
What is the approximate temperature of the Core?
6000’c
Are the minerals that occur naturally in the Earth’s crust elements or compounds?
Both
What do we commonly call the mixtures of these minerals in the Earth’s crust?
Rocks
Name the top 5, most common occuring, elements in the Earth’s crust
Oxygen (47%), Silicon (28%), Aluminium (8%), Iron (5%), Calcium (3.5%)
Fill in the missing words:
The Earth’s ______ is cracked into large pieces called _______ Plates. These float on the _______, moving due to __________ in the mantle. They usually move very _______. only a few ____ each year. When they move more suddenly, they create ________. _________ and _________ often occur where two plates meet.
The Earth’s CRUST is cracked into large pieces called TECTONIC Plates. These float on the MANTLE, moving due to CONVECTION in the mantle. They usually move very SLOWLY. only a few CENTIMETRES each year. When they move more suddenly, they can create EARTHQUAKES. EARTHQUAKES and VOLCANOS often occur where two plates meet.
Weathering breaks all types of rocks into small pieces called?
Sediments
Does weathering occur quickly or over a long period of time?
Long period of time
What are the three types of weathering?
physical, chemical, biological
What is Erosion?
the movement of the broken pieces of rock to a new location.
What is the common name of the type of weathering described below:
Water repeatedly freezes in cracks and spaces inside rocks. When the water freezes it expands, when the water thaws it contracts. The repeated change in forces results in cracks widening and eventually pieces of rock break off.
Freeze Thaw Weathering
Name two types of physical weathering
Freeze Thaw and Onion Skin
Describe Onion Skin weathering.
During the day, the hot sun heats the surface of the rock and it expands. At night the temperature reduces and the surface cools and contracts. The repetition of heating and cooling, expansion and contraction, over long periods of time cause cracks to form in the surface and the outer layer eventually falls off.
Name a source of chemical weathering.
Acid Rain