Zusammenfassung der Ressource
Sedimentary
Rock Formation
& Fossils
- Weathering breaks rocks into fragments, which are
transported to the ocean by rivers. The fragments
fall to the bottom of the ocean as sediments.
- The sediment particles become
squashed (compaction) and are
cemented together by mineral.
After a very long time,
sedimentary rock is formed.
- Sedimentary rock changes into
metamorphic rock when it comes
under heat and pressure. This
happens because it gets buried
deep underground and comes
close to hot molten rock.
- The particles in chalk and
limestone are rearranged to form
marble.
- Fossils form in
sedimentary rock
when:
- Organisms fall
into sediment.
- There is not enough oxygen to cause the organism to decay.
- The organism has
hard enough parts to
leave a caste in the
forming rock.
- Water filtering through
the rock deposits
minerals in the caste.
- Chalk is full of
microscopic fossils
because of the sediment
from which it is made
comes from the shells of
microscopic sea
organisms.