Download Chapter 8 Science Test Notes

Chapter 8 Science Test Notes
Studying Earth’s Past
• The method of
dating that relies on
the decay of
radioactive isotopes
is called radiometric
dating.
• Absolute dating is
any method of
measuring the age
of an object in
years.
• “Younger over older”
is a phrase that can
be used to
remember
superposition.
• Radioactive decay
occurs at a constant
rate.
• Paleontology is the
study of the history of
life.
• Fossils cannot provide
evidence about how
Earth looked 4.5 billion
years ago.
• The idea that geological
change happens
suddenly is called
catastrophism.
If I try, I could be the greatest
Scientist in the World. I could be
King/Queen of the World.
• The idea that
geologic processes
gradually occur as
they have in the
past is called
uniformitarianism.
• During radioactive
decay, radioactive
isotopes break down
into stable isotopes of
other elements.
• To determine the
absolute age of a rock,
a scientist needs to
know the rate of decay
for a radioactive
element in the rock.
• Tilting is the slanting of
rock layers.
• Fossils are most often
formed in sedimentary
rock.
• After every half-life, the
amount of radioactive
material in a substance
decreases by one-half.
• To determine the
most accurate and
precise age of
Earth’s oldest rocks,
geologists would use
the uranium-lead
method.
• Erosion is one of the
major causes of the
missing rock layers
known as
unconformities.
• Comparing rock
layers with other
rock layers is called
relative dating.
• Unconformity
represents a missing
part of the geologic
record.
• The law of
crosscutting
relationships states
a fault or body of
rock is younger than
the body of rock it
passes through.
• Sedimentary rock is
formed when
sediment is lithified.
• Molten rock that
squeezes into
existing rock and
cools is called
intrusion.
What did one duck say to other duck
when he saw a meteor falling from
the sky?
• Global climate
change may have
caused the
extinction of the
dinosaurs.
• Atoms with the
same number of
protons but a
different number of
neutrons are called
isotopes.
• A fault is a break in
the Earth’s crust.
• When rock layers
are horizontal,
geologist know that
the rock layers are
undisturbed.
• An asteroid hitting
the Earth could be
an example of a
catastrophe.
• To make a good
pizza, you need lots
of cheese and
pepperoni.
Don’t Feed the Raccoons!