29q-60q Flashcards
What is an uncomformity?
An entire layer is missing cause gaps in geological history.
What 3 thing can cause an uncomformity?
- lack of deposition
- layers form beneath water
- layers exposed to weathering and erosion
What is lithification? Name the steps of lithification.
The process in which sediment becomes sedimentary rock.
- erosion
- deposition
- compaction
- cements
What are agents of change?
gravity, water, wind, ice, people
How are metamorphic rocks formed?
heat and pressure
What is the principle of uniformitarianism?
geological processes that occur today, occurred the same way in the past.
What is a half life?
The time it takes for half a parent to decay into a daughter.
What is evolution?
Process in which organisms change over time.
Who was Charles Darwin?
A scientist who believed that more advantageous organisms would survive and reproduce.
Summarize the theory of natural selection.
- Organisms produce more offspring than can survive
- Variations exist within populations
- Some variations are better than other for survival and reproduction
- individuals with better variations will survive and reproduce
Fossils provide evidence of what?
landscape, climate, and animal changes
What does extinct mean?
no longer in existence
What is a variation?
A mutation in a gene or chromosome
What is an adaption?
something that helps an organism survive
Variations are the result of?
mutations in a gene or chromosome