Rocks and Landscapes by LeannePresentation Transcript
Rocks and Landscapes!
Rocks can be divided into three types! Igneous Sedimentary Metamorphic
The Rock Cycle
The Rock Cycle 1. Magma cools to form crystals which forms Igneous rock 2. Igneous rock weathers to form Sediment 3. The Sediment is transported and deposited in the sea. 4 . The Sediment becomes compact & compressed under more sediment, therefore the heat & pressure causes metamorphism.
5. Metamorphism changes the Sediment into Metamorphic rock. 6. The Metamorphic rock, carries on being squashed and compressed causing more pressure and heat 7. So the temperatures rises and then the Metamorphic rock begins to melt 8. The molten rock then becomes Magma 9. The cycle starts again
Igneous How is Igneous formed? Igneous rock is formed underground, this happens because the melted rock called magma which is deep within the Earth becomes trapped in small holes. When the magma cools down slowly it turns into Igneous rock producing large crystals However Igneous rock can also be formed above the ground, this is when volcanoes erupt and causes magma to rise above the Earths surface. When it cools down rapidly on the surface it becomes Igneous rock producing small crystals .
Igneous rock Pumice rock is formed when lava cools down quickly above the ground . Pumice rock is very light Which makes the rock float In water. Pumice is a kind of Glass not a mixture of minerals. Pumice is used as decorative Landscape stone. Pumice
An Intrusive rock
Is hard resistant rock that forms upland areas such as Dartmoor.
Granite is formed when large masses of molten material is forced up into the Earth’s crust It then cools slowly under pressure deep underground How is Granite formed? Granite is:
Sedimentary How is Sedimentary formed? Sedimentary rock is little pieces of the Earth. Which is then eroded and worn away because of strong gales such as wind and water. They are washed down stream, and then they sink to the bottom of the oceans. This happens constantly which makes layer after layer of eroded Earth. It is then deposited on top of each other, the layers get compressed down until the bottom layer turns to rock.
Sedimentary Sandstone Sandstone is made from small grains of the minerals quartz and feldspar. Sandstone is often formed in layers. Sandstone is often used as building stone.
Sedimentary Chalk White/grey rock with many fine pore spaces Chalk has bedding planes and joints Chalk is very permeable, little surface drainage Forms hills such as the Chilterns Used in cement making
Sedimentary Carboniferous Limestone A hard grey rock composed of Calcium Carbonate Has prominent bedding planes and many joints Very permeable with little surface drainage Forms upland areas in the Yorkshire Dales
Metamorphic How is Metamorphic formed? Metamorphic rocks are morphed into another kind of rock. The rocks that were morphed to form Metamorphic rock are Sedimentary & Igneous rock. Also Metamorphic rock is formed when Sedimentary rock is altered by pressure or heat in the crust deep below the Earths surface.
Metamorphic Gneiss Gneiss rock could have been Granite which is am Igneous rock but heat and pressure has changed it. The mineral grains in the rock became flattened by heat and pressure resulting in the Gneiss rock to look different Grey/pink in colour
Metamorphic Marble Marble was once Limestone The heat and pressure caused the Limestone to re-crystallize Marble is different colours due to Foreign substances often entering the rock in process Marble is the most elegant stone/rock It is versatile enough for the use throughout the home
Metamorphic Slate Is fine grain rock formed when Sedimentary rock such as shale becomes metamorphosed by pressure Slate is thin, and broad layers The average colour of Slate is grey-blue Slate is used in making roofs
Questions & answers? Revision 1. What do all Igneous rocks have in common? 2. What is the difference between Granite & Lava? All Igneous rock starts out as Magma and forms different size crystals! Granite rock is a solid, whereas Lava is a liquid. You can build things with Granite, but not with Lava. Granite is formed by Igneous rock.
3. Is Granite an Intrusive or Extrusive Igneous rock? It is an Intrusive Rock 4. What size crystals would Granite produce? Small Crystals 5. What is Limestone made of? Calcium Carbonate
Glossary Igneous rock – rock formed when molten rock has cooled and solidified Bed – A layer of sediment or sedimentary rock Intrusive rock – Igneous rock that forms when magma cools below the Earth’s surface Metamorphic rock – Rocks that are changed from Sedimentary, Igneous by intense pressure & heat Bedding Planes – Horizontal limes in the rocks Impermeable – meaning water cannot sink into/through the rock Permeable – the water can flow and sink into the rock – allows water in
Permeable – the water can flow and sink into the rock – allows water in Rock Cycle – shows how rock are created. Destroyed and transformed and has four processes – erosion, weathering, transportation & deposition Weathering – breaking of rocks by water, snow & ice Sedimentary rock – Rock formed from rock types that have weathered and compressed together over time.