radioactive decay, radiometric dating, earth's age
As parent atoms decay, they release radiation and break down into a new element called a ___________ atom. This happens at a ________ rate.
As parent atoms decay, they release radiation and break down into a new element called a daughter atom. This happens at a unchanging rate.
How do scientists use parent and daughter atoms in radiometric dating?
By counting the number of atoms in the parent and the number of atoms in the daughter, scientists can figure out how long they have been there.
The isotope used to find the age of organic objects less than 30,000 years old is
Carbon
The time it takes for half of the radioactive atoms in a sample to decay
half life
When half of the parent atoms have turned into daughter atoms, this is called
half life
Radioactive isotopes originate in magma and can be found in this type of rock
igneous
The most commonly used type of radiomettric dating analyzes _____________-40 and argon- 40 levels
potassium
Scientists can use ____________ _______________ to determine the age of the earth.
radiometric dating
Using the rate of decay of unstable isotopes to find the age of rocks and fossils
radiometric dating
why would it be difficult to find rocks older than about 4 billion years old on earth?
rocks are constantly being destroyed and reformed
How old is the oldest dated mineral on earth?
4.4 billion years
Roughly how old is the earth?
4.54 billion years old
Device that analyzes the amounts of specific isotopes in the sample
Mass Spectrometer
Have geologists found pieces of earth (rocks) that have been around since it (earth) was "born"? Explain why/why not
No, rocks are always being destroyed and reformed making it hard
How did scientists figure out that the earth is older than the oldest earth rock?
Scientist dated meteors
For billions of years the earth has been bombarded (hit) by asteroids, comets, and planetesimals (mini-planets). Why don't we see much evidence (proof) of all those impacts?
The earths existense pror to humans was much longer
Why would we expect older surfaces to have more and larger craters than a younger surface?
The impact created by meteorites that have landed on those surfaces. The older it is the more and deeper craters will be found.
Why are moon rocks younger than Earth rocks?
The moon formed after the earth crashed
What is the purpose of dating moon rocks
The moon is believed to have formed when a protoplanet smashed into the earth, meaning the minerals that make up the moon are around the same age as the earth
Why are objects such as meterorites useful for dating the age of the earth.
They originate from material that formed when the solar system formed, so they were formed around the same time as the earth. They also travel around with no atmosphere that could change them.
Element that decays into lead, used to date very old rocks
Uranium
What element does science find most useful for dating rocks?
Uranium
The find the age of rocks using radiometric dating, you must_______ the amount of parent and daughter isotopes
compare
The oldest rock ever "dated" came from...
the moon