Unit 4 - Fossils & Age of The Earth Flashcards
What is strata?
layers of sedimentary ricks
Where are the oldest layers on this geologic timeline?
at the bottom of
On most geologic time scales like this, how old are the oldest rocks?
4.6 billion years old
______________________ is the belief that geologic processes happen slowly today, just as they have always happened in the past. _______________________ is the belief that most of the geologic features we see today are the result of large scale catastrophes such as earthquakes and floods.
uniforminism
catasrophisum
What are index fossils?
rocks that are unique to a single layer of rock and is used to tell wwhat time period the other rocks are in
What types of creatures are most commonly found as fossils in the fossil record?
hard shelled cratures
How is a fossil mold formed?
impression made by shell/bone
How is a cast formed?
sediment fills the mold
How does an organism become petrified?
fossil decomposes and slowly spaces are filled by mineral rich water
How does it become permineralized?
organism decays then mineral filled water disolves , mineral seeps into cells
What types of organisms (or parts of organisms) are most often found carbonized?
feathers leaves
What are trace fossils?
fossils leave evidence of life
What is a gastrolith? What is a coprolite?
smoothe stone dino stomach, fossilized poop
In which type of rock – sedimentary, metamorphic or igneous – are fossils formed?
sedimentary
How does igneous rock form?
magma cools and solitifies
How does sedimentary rock form?
layers of rock diposite don top one nother
How does metamorphic rock form?
intense heat / pressure on rock
Which radioactive isotope is often used to determine the age of a once-living thing?
carbon 14
If a radioactive isotope contains 100g of a substance, and the substance’s half-life is 60 seconds, after 60 seconds, how many grams of the isotope will remain?After 60 more seconds pass, how many grams of the isotope will remain?
How much will remain 60 seconds after that (3 half-lives)?
50, 25,12.5
Original preservation of an ancient organism is very rare. Describe two different ways it can happen.
- frozen 2.dried 3. no oxygen
Review the different views that Christians have about the age of the Earth.
- day age theory- day isnt 24 hours . in the hebrew bible it says time periods , never says each was a day .
- this would make sense why some scientists have different opinions cause God could have taken as much time as he wanted, or made it look like it happend
- i do not agree with the intermintent day theory, because what do we think happened in the gaps?
Why is humility so important in Scientific study?
we all make mistakes
