Rocks Flashcards
What is sedimentary rock?
Sedimentary rock is an accumulation of sediment that has joined together to make one individual rock.
What is igneous rock?
Igneous rock is formed when magma cools slowly developing round grains as they have melted and crystals.
What is metamorphic rock?
Metamorphic rock tends to be rock that has layers in that are flattened and foliated.
Sedimentary rock + esctreme heat + extreme pressure + millions of years = metamorphic rock.
What is freeze thaw weathering?
Freeze thaw weathering is when:
- A crack is formed and water or rain becomes trapped in there.
- When the temperature drops below freezing the water will freeze and expand putting pressure on the rock.
- Then as the temperature increase it will melt wearing the rock away and causing irregular fragments and sediment usually ending up being deposited at say the bottom of the slope.
What is onion skin weathering?
During the day sun shines on rocks and causes them to expand. Then when temperatures decrease it contracts and when this process is continually repeated it causes flakes of rock to fall off or erode.
What is chemical, biological and physical weathering?
Biological weathering is the wearing away or weakening of rocks through plants, animals or micro-organisms.
Chemical weathering is the erosion or disintegration or rocks through chemical reactions e.g. acid rain,
Physical weathering is the breaking apart of rocks without changing the chemical composition. E.g.the structure of the earth or movement.
What are seismic waves?
Seismic waves travel through rock yet there are two types or waves, p and S waves.
P waves can travel through liquids and solids whereas S waves can only travel through solids.
What is the structure of the earth like?
The structure of the earth has many layers. I’m the very centre is the inner core (solid) then comes the outta core (solid and liquid)
then the mantle ( solid and liquid) and then the crust ( solid). P waves can travel through the earth but S waves can’t as they are refracted at the boundaries telling us there are layers and liquids in the the earth.
How do fossils form?
Fossils form in sedimentary rock.
The living organism is placed in the ground then sediment becomes layered on top of it. Over time the sort tissue daisys leaving only bones and shells behind then he remains form an imprint. Next minerals fill the exposed gaps and soon the bones are weathered away by erosion Levine a fossil imprint and minerals in its place.
