Relative Age
The horizontal strata of the Grand Canyon, the bottom layers are _______________ the layers above them.
a. older than
b. younger than
c. the same age as
a. older than
The Appalachian Mountains began forming more than 480 million years ago when thick layers of Earth's crust were folded and changed by heat and pressure.
When did Appalachian Mountains began forming?
a. 65
b. 110
c. 250
d. 480
D. 480
Scientists measure this to determine the exact age of fossils.
What are radioactive elements/half-life?
These are the Three Era's of the Phanerozoic in order from oldest to newest.
What are Paleozoic, Mesozoic, and Cenozoic?
This is how the Dinosaurs became extinct.
What are an asteroid impact and volcanic eruptions?
a feature that cuts across rock strata, such as: Toroweap Fault, is _____________ the rock layers it cuts through.
a. older than
b. younger than
c. the same age as the rock layers it cuts through.
b. younger than
This collision created a mountain range similar to today's ________
a. Atlantic Ocean
b. San Andreas Fault
c. Pangea
d. Himalayan
d. Himalayan
This is the time it takes for half of the mass of an original element to change into a new product.
What is Half-Life?
This is how long ago the Earth was formed.
What is 4.6 Billion Years ago?
Geologists learn about the order of rock layers using the law of
a. original horizontality
b. superposition
c. inclusion
B. Superposition
When this supercontinent broke apart, the Atlantic Ocean formed, and over millions of years, erosion wore down the mountains into the _________ we see today.
a. Atlantic Ocean
b. rolling hills
d. Himalayan Mountain
B. Rolling Hills
These are the first living organisms.
What is bacteria?
The Era that we are living now?
A. Mesozoic
B. Paleozoic
c. Cenozoic
c. Cenozoic
The Paleozoic-Mesozoic boundary is known as the “Great Dying” because it has been linked to the largest mass extinction in Earth's history about 252 million years ago. Scientists have connected the mass extinction event to volcanic rocks that cover Siberian Traps in the northern part of Russia. Large sulfur deposits in rock layers from that time indicate major atmospheric changes sulfur and ash in rock layers suggest that volcanic gases played a role in the mass extinction.
a. trilobites
b. meteorite fragments
d. sulfur and ash in rock layers
C. sulfur and ash in rock layers
These are footprints or burrows left by ancient organisms .
What are trace fossils?
Scientists can determine the approximate date of the volcanic eruptions by analyzing ____________ within volcanic ash layers, which date to about 252 million years ago.
a. iron deposits
b. meteorite fragments
c. zircon crystals
c. zircon crystals
Which is the biggest part of the Earth's History?
a. Cambrian
B. Precambrian
c. K-Pg
A. Precambrian
Describe the amount of time that Humans have been around on Earth in comparison to the amount of time the Earth has been around.
a. short
b. long
c. massive
A
The Paleozoic-Mesozoic boundary is known as the “Great Dying” because it has been linked to the largest mass extinction in Earth's history about 252 million years ago. Scientists have connected the mass extinction event to volcanic rocks that cover Siberian Traps in the northern part of Russia. The extinction of ___________ from the fossil record further supports the timing of the event.
a. trilobites
b. sulfur and ash
c. marine species
c. marine species
This is the other method of determining an age of a fossil that is not exact.
What is relative age?
The geologist shows the Luna family a fossilized canine tooth from a saber-toothed cat (Smilodon californicus), a species that roamed this region between 10,000 and 2.5 million years ago. This fossil was found in the newest layer of rock on their ranch.
_________ was most likely to contain this fossilized canine tooth and other fossils from the same time period.
Choose the correct letter to complete the sentence.
a. Layer A fossilized canine tooth from a saber-toothed cat
B. Layer B fossilized marine animals
C. Layer E Fossilized plants
Layer A