Riddles It is greater than God and more evil than the devil. The poor have it, the rich need it and if you eat it you'll die. What is it? What has a head, a tail, is brown, and has no legs?
AFV
Geologic Time Notes Page 3 ©Mark Place, 2009-2010 www.LearnEarthScience.com
Fossils can only be found in rocks. sedimentary
On to the next question...
never lived at the same time Why is this statement false: “The caveman had dinosaur for breakfast.”? man and dinosaurs never lived at the same time
Answers to Questions on Page 3 On to page 4....
Relative Age If a sedimentary rock outcrop has not been overturned, which layer would be the oldest? What is this principle known as?
oldest rock layers are on bottom Principle of Superposition
Using this principle, label the strata below from oldest to youngest.
On to the next question...
Faults are always (older, younger) than the rocks they cut through.
there first (it's older) Which is older: F or S How do you know? F cuts through S S must have been there first (it's older)
On to the next question...
If a geologist finds an igneous sill, how can she determine if the sill is an intrusion or an extrusion?
contact metamorphism on all sides Intrusions contact metamorphism on all sides
no contact metamorphism on top extrusions no contact metamorphism on top
Is “H” an intrusion or extrusion? How can you tell?
H is an intrusion. Contact metamorphism on top
On to the next question...
a buried erosional surface What is an unconformity? a buried erosional surface How does it complicate the relative dating of rock layers? a part of the rock record is missing
weathering and erosion What processes could lead to an unconformity? weathering and erosion
Using the diagram to the left, identify where the unconformity is located by drawing an arrow and writing the word “unconformity” next to it.
On to the next question...
What characteristics must fossils have in order to be good index fossils? lived over a large geographic area (large horizontal distribution) lived for a short period of time (small vertical distribution)
In geology, this is referred to as CORRELATION In the diagram below, a geologist has matched up rock layers based on index fossils.
On to the next question...
Evolution organisms adapt to their environment in order to survive Explain the theory of evolution. organisms adapt to their environment in order to survive
Evolution can see that different organisms have changed over time Explain how the fossil record supports this theory can see that different organisms have changed over time
their half-lives are constant Absolute Age Why are radioactive isotopes useful in determining the absolute age of a rock? their half-lives are constant
NOTHING! it is reliable to calculate age Absolute Age What can be done to change the half-life of a radioactive isotope? Why is this important? NOTHING! it is reliable to calculate age
stable atoms unstable atoms Draw the generic graph for the half-life of a radioactive isotope. stable atoms unstable atoms
carbon-14 What radioactive isotope could be Absolute Age What radioactive isotope could be used to determine the absolute age of material that was recently living? carbon-14
What is the half life of uranium-238? Please answer the two questions on page 7 of your Notes What is the half life of uranium-238? 4.5 x 109 4,500,000,000 4.5 billion years choice (c)
3 half-lives x (5.7 x 103) =1.71 x 104 = 17,100 years Please answer the two questions on page 7 of your Notes If there is a 100g sample of C14, how many grams of C14 would remain after three half-lives? How long would this take? Show all work. 100g 50g 25g 12.5g 3 half-lives x (5.7 x 103) =1.71 x 104 = 17,100 years
Shroud of Turin
AFV