E.10 Flashcards
how are fossils formed
A plant or animal dies and is buried by deposited sediments and forms a fossil as sedimentary rock forms
can anything be turned into a fossil
No, sediments must quickly bury the organism before scavengers and decomposers break it down.
what is petrified wood
Minerals slowly replace parts of the wood
What can strata tell us about what the Earth used to look like?
Environment - types of rock are formed in different environments (ex. Limestone is formed under the ocean)
Timeline - thicker strata layers shows the environment stayed the same for a while
Events/Change - new layers of strata tell us that something changed in the environment
what is a trace fossil
The imprint of an organism left behind
what is a cast fossil
Rock that filled in an imprint left behind by an organism.
