Paleontology Study Guide Answers . Please take a sheet of paper and label it “extra info” . #1 How do scientists date material older than 50,000 years? Younger than 50,000? . Older than 50,000 = Uranium lead Method Younger than 50,000 = Carbon-14 Method. - PowerPoint PPT Presentation
Paleontology Study Guide Answers
PaleontologyStudy Guide Answers Please take a sheet of paper and label it extra info
Older than 50,000 = Uranium lead Method
Younger than 50,000 = Carbon-14 Method#1 How do scientists date material older than 50,000 years? Younger than 50,000? Sedimentary#2 What type of rock are most fossils found in? Where dry land was once under water Example: shark tooth in Georgia How the environment has changed #3 What can fossils tell us about an areas history? Younger rocks are on the top.Older rocks are on the bottom.Layers must be undisturbed#4 What does the law of superposition state?
Mineral Replacement Usually happens to wood or bones#5 What is petrification?
PrecambrianPaleozoicMesozoic Cenozoic *Currently we are in the cenozoic#6 List the Geological eras in order from earliest to most recentHint: ThinkAlphabetApproximately 4.6 BILLION Years#7 How old is the Eaths History date back to?
Index fossils are used to determine relative age.
Index fossils are widespread geographically, are limited to a short span of geologic time, and occur in large numbers.
Its an actual FOSSIL
Trace fossils are indirect evidence of prehistoric life.Can tell us about the activity of an animal Examples: Footprints, trails, poop
#8 Whats the difference between index and trace fossils
Sequence Age COMPARED to other rocksOlder or younger NO NUMBERUses:Index fossilsLaw of superpositionLaw of original horizontality
#9 What is relative age and how do you find the relative age?
Most precise Gives an actual agePuts a number to the age. This is why we use it! Uses: Radioactive decayCarbon 14 or uranium lead Half-life #10 What is absolute age?
Geological changes such as dry areas that were once under water Organisms have become more complex and how they have evolved How the environment looked in the past How rock layers in different areas match upHow environment/animals have changed The age of certain layers of rocks
#11 What can scientists learn from studying fossils? Uniformitarianism the idea that the same geologic processes shaping the Earth today have been at work throughout Earths history
#12 What is uniformitarianism? What is original horizontality
The principle of original horizontality means that layers of sediment are generally deposited in a horizontal position.
Eons-eras-periods-epochsBroken up so its more manageable Eras are broken by a huge climate change or mass extinction
#13 How is the geologic time scale broken downDryAnd Freezing
Temperatures#14 What slows down the decaying processClimate changeMaybe:Pange breaking apart Or Asteroid causing a huge dust cloud#15 What do scientists think caused the extinction of dinosaurs?
Most organisms dont become fossils #16 Are fossil records complete or incomplete? Why?Flood, mudslide, volcanic ash, earthquake, etc.
Can lead to the formation of fossils #17 What is a catastrophic event?Mold: cavity where an organism once was (cakepan)
Cast: sediment that fills the cavity (batter)#18 cast vs. mold
Needs to have a rapid burial and have the hard parts of the organism be preserved!!! #19. How are fossils formed?Theyve become more complex
One cell to humans#20. what do fossil records tell us about organisms