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Worksheets7th Grade History of Earth -Eons and Eras
Total questions: 46
Worksheet time: 30mins
When was the Earth Formed?
100 Years Ago
4.6 Billion Years Ago
2019 Years Ago
16.7 Million Years Ago
What are the 4 Eons in order?
Hadean, Proterozoic, Archean, Phanerozoic
Hadean, Archean, Proterozoic, Phanerozoic
Archean, Hadean, Proterozoic, Present
Hadean, Archean, Proterozoic, Mealrozoic
The most present eon continues to this day starting back about 540 million years ago. During this eon, organisms evolved and died in mass numbers, but also includes the start of human life. What is the name of this eon?
Hadean
Archean
Phanerozoic
Proterozoic
In this eon multicellular life was created. During this eon the Earth was considered the Snowball Earth and the Oxygen Catastrophe occurred causing loss of oxygen on our Earth. This eon is also the 3rd eon in Earth’s history. Which eon is this?
Archean
Hadean
Proterozoic
Phanerozoic
The moon formed during this eon, this eon occured before life and before the crust had solidified. Lava and magma was everywhere, and lots of comets bombarded the earth, giving the earth the large amounts of water you see today. Which eon is this?
Hadean
Archean
Proterozoic
Phanerozoic
The moon formed during this eon because a Mars sized planet glanced of the earth, sending some of the earth's top layers and some of this planet going into orbit around the earth, as many small asteroids, which eventually formed one mass of rock, the moon we see today. The moon now causes the tides, low tide and high tide. What eon is this?
Hadean
Archean
Proterozoic
Phanerozoic
During which Eon did 96% of marine species as well as a similar amount of land animals perish that could’ve been caused by volcanic eruptions? (Hint: Called "The Great Dying")
Phanerozoic
Archean
Hadean
Proterozoic
What 2 pieces of evidence is most helpful in understanding events that occurred in Earth’s past?
Layers of Rock
Fossils
The Geologic Time Scale
Scientific Tools
What was the effect of Earth’s crust forming?
Plants were able to photosynthesize by getting minerals from the soil
Life could form on Earth
Animals could build habitats to live in
The ocean formed
What was the effect of "The Great Dying"?
If allowed plants to thrive.
Almost all organisms perished, which started the evolution of dinosaurs.
All organisms could now walk on land and swim in water.
Water was now more affordable for organisms in any area.
The Earth’s temperature became more even and cooled down. Water vapor formed oceans and the Earth was cool enough to form the first continent, Vaalbara. Oxygen was released into the atmosphere (Great Oxygenation Event) and the first life formed. What eon is this?
Archean
Hadean
Proterozoic
Phanerozoic
index fossil - a fossil of
widely distributed organisms that lived during extended periods
widely distributed organisms that lived during only one short period
narrowly distributed organisms that lived during extended periods
narrowly distributed organisms that lived during only one short period
The Law of Superposition - In sedimentary rock layers
each layer is older than the one above it
each layer is younger than the one above it
each layer is older than the one below it
each layer is relative age
geologic time scale - a record of the geologic events and life forms in
the fault of a rock
the index of a fossil
the superiority of a position
the history of Earth
The geologic time scale is divided up 4 large units of time called:
Eons
Eras
Periods
Epochs
The oldest eon is called:
Proterozoic
Paleozoic
Hadean
Archean
What were the earliest life forms on Earth?
simple, multicellular organisms
unicellular plants
photosynthesizing bacteria
anaerobic bacteria
Which was the last life form to emerge on Earth?
insects
reptiles
flowers
humans
What is not a possible cause for the mass extinction events that occurred during the Phanerozoic Eon?
asteroid impact
climate change
volcanism
humans
In which of the following eras did humans first appear in the fossil record?
Precambrian
Paleozoic
Mesozoic
Cenozoic
When did the age of mammals begin?
Once the big mean dinosaurs died off. End of Mesozoic
After the Cambrian explosion
After Lunch
The end of the Cenozoic
A fossil of widely-distributed organisms that lived during only one short period
absolute age
index fossil
law of superposition
relative age
Correctly sequence the layers of rocks oldest to youngest
A,D, C, B, E
E, B,C D, A
B,E,C, D, A
what is the Paleozoic era?
Mesozoic Era
the era of jesus Christ
the earliest of three geologic eras of the Phanerozoic Eon. It is the longest of the Phanerozoic eras.
Primitive fish and reptiles, land plants, and insects
What is the Cenozoic era?
The youngest era of the Phanerozoic eon
The oldest of the Phanerozoic eon
the longest lasting era of the Phanerozoic eon
idek I don’t speak this language
1 Paleozoic
2 Cenozoic
3 Precambrian
4 Mesozoic
