28 questions
When is it speculated that Earth first formed?
~3.6 billion years ago
~4.6 million years ago
~4.6 billion years ago
Last Saturday
What type of unconformity is shown between D and C in the figure?
nonconformity
disconformity
angular unconformity
uniformatarianism
A sample of a radioactive element has a mass of 80 g. How much parent and daughter materials are in the sample after two half-lives?
parent = 20 g; daughter = 60 g
parent = 80 g; daughter = 80 g
parent = 2; daughter = 1/2
parent = 60 g; daughter = 20 g
The discovery of fossilized coral reefs on land is evidence that
salt water changes coral into fossils.
the sea level has changed over time.
the reefs formed in a freshwater lake.
coral reefs can form on dry land.
Which of the following is NOT an uncomformity
deposition stops after a supply of sediment is cut off
erosion moves layers
a break in geologic record
gravity causes sediment to form layers