rocks Flashcards
what are the tree types of rocks
igneous rock
sedimentary rock and
metamorphic rock
give 2 types of sedimentary rock
limestone and chalk
give 2 types of igneous rock
granite and basalt
give 2 types of metamorphic rock
marble and slate
what is formed by molten magma which is pushed up to the surface of the crust?
igneous rock
how are sedimentary rock formed
These little bits of our earth are washed downstream where they settle to the bottom of the rivers, lakes, and oceans. Layer after layer of eroded earth is deposited on top of each. These layers are pressed down more and more through time, until the bottom layers slowly turn into rock
how is metamorphic formed ?
The rocks are under tons and tons of pressure, which fosters heat build up, and this causes them to change. If you exam metamorphic rock samples closely, you’ll discover how flattened some of the grains in the rock are.
how is igneous rock formed?
they are formed when the melted rock, called magma, deep within the earth becomes trapped in small pockets. As these pockets of magma cool slowly underground, the magma becomes igneous rocks.
Igneous rocks are also formed when volcanoes erupt, causing the magma to rise above the earth’s surface. When magma appears above the earth, it is called lava. Igneous rocks are formed as the lava cools above ground.
what is physical weathering
Physical weathering is caused by physical changes such as changes in temperature, freezing and thawing, and the effects of wind, rain and waves.
what is chemical weathering?
Animals and plants can wear away rocks. This is called biological weathering. For example, burrowing animals such as rabbits can burrow into a crack in a rock, making it bigger and splitting the rock.
what is biological weathering?
The weathering of rocks by chemicals is called chemical weathering. Rainwater is naturally slightly acidic because carbon dioxide from the air dissolves in it. Minerals in rocks may react with the rainwater, causing the rock to be weathered.
what is weathering?
braking down rocks
how many years does the rock cycle take
millions of years
what is erosion
wearing down rocks
what is transportation
moving the eroded bittes of rocks round the world by wind and water
