3-CGC1W1 Rock Types and The Rock Cycle

Examples of Sedimentary rocks

Limestone

Chalk

Sandstone

Describe sandstone

An orangey-coloured rock which looks like lots of sand grains tuck together

Soft, breaks easily

Describe Limestone

A grey/white rock which is mostly made up of crushed sea shells (living organisms)

Contains fossils

Describe chalk

Fine grains

Contains fossils

What are the properties of sedimentary rocks?

Sedimentary rocks have layers showing the deposition of sediment at different time periods

Weak grains together

Fossils trapped within them

Sedimentary consist of layers of lots of small particles that are called..

Porous

Why are sedimentary rocks near the surface younger than sedimentary rocks deeper down?

The sediments deeper down are older because they’ve had more time to grow

The sediments near the surface are younger because they’ve had less time to grow than the ones deeper down

Stages of how sedimentary rocks get formed

Fast flowing water

Slow water

Pressure

Sedimentary rocks can also be formed when..

Minerals which are left behind when water evaporates

Examples of Metamorphic rock

Marble and slate

Properties of metamorphic rocks

Layer of structures of crystals caused by the effect of heat and pressure

Denser and harder than sedimentary rocks

Wavy and zig-zag arrangement because of no space particles, which are squares.

How metamorphic rocks are formed

Pressure from surface rocks together

Heat

Marble

A hard smooth rock made from sedimentary limestone or chalk in conditions of strong heat and low pressure

Slate

A grey rock with fine grains made from sedimentary shale in conditions of low temperature and low pressure

Thin sheets

Examples of igneous rocks

Granite

Pumice

Basalt

Granite

Hard grey rock with random arranged crystals

Pumice

Pale grey rock made up of very small crystals and porous, which is extremely light

Basalt

A dark glassy rock which has very fine crystals and often forms as columns of rock

Properties of igneous rocks

Interlocking crystals

Never contains fossils

How are igneous rocks formed?

Magma/lava cools and solidifies

Above - extrusive

Below - intrusive

Size of crystals

Above - small crystals are formed

Below - large crystals are formed

Rock cycle