MODULE 10 - Different Methods of Determining the Age of Stratified Rocks Flashcards
What do geologists use to figure out if a rock is older or younger than another
rock
Relative dating
What absolute dating technique depends on the traces of radioactive isotopes
found in fossils?
Radiometric
It is the process of breaking down of isotopes.
Radioactive decay
It is known as atoms of the same element that have the same number of protons
but different numbers of neutron?
Absolute dating
What term is used to describe absolute dating?
Exact
What can be used to show the approximate age of rock?
Fossil index
In a canyon, where is youngest rock located
Top
What is a gap in the rock sequence?
Unconformity
What is the time needed for one-half of the parent atoms to turn into daughter
atoms?
Half-life
What technique uses the half-life of atoms to figure out the age of the rock
layers the atoms are in?
Radiometric
What method has helped scientists to determine the exact age of Earth?
Absolute dating
What is a good element to use to date fossils and some rock?
Carbon
What technique explains that the lowest layer is the oldest while the topmost
layer is the youngest layer just like the clothes in the laundry basket?
Stratigraphy
What method evaluates the exact age of the sample?
Absolute dating
What type of dating method can be used on rock layers by applying the law
of superposition?
Relative dating
What indicates the relative age of a rock layer?
The position of the layer compared to other layers
How can the absolute age of a rock be determined?
By measuring the amount of isotope and calculating the half-lives passed
How many half-lives have passed if a rock contains 25% isotopes and 75%
daughter isotopes?
2 half-lives
What describes relative dating?
Arranges fossils in order
The half-life of carbon-14 is known to be 5720 years. It is the the most
popular and widely used types of radioactive isotope. Why do you think it is
a good element to use to date fossils and some rock?
Shorter half-life means more accurate age
What happens when the isotopes decay?
Parent isotopes become half
What is the importance of dating?
It determines the age of fossils
What is the extended version of the stratigraphy?
Biostratigraphy
