Name__________________________________
Teacher________________________________
Science 8.____
Date_______________
Earth History Mid-Summative Exam 6 Study Guide
1. Vocabulary
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Geological Time: ___________________________________________________________________
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Era - ___________________________________________________________________________
o Precambrian Era - ______________________________________________________________
o Paleozoic Era –______________________________________________________________
o Mesozoic Era –______________________________________________________________
o Cenozoic Era -______________________________________________________________
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Period - __________________________________________________________________________
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Unconformity - _____________________________________________________________________
2. What are three characteristics of a correct geological timeline?
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Geologists have discovered many rock layers in the Grand Canyon and have been able to determine their
approximate ages. The ages are listed below. Use this information and the Geological Time Scale on the
following page to complete the Geological Time Line in Question 3.
Grand Canyon Rocks
Rock Name
Temple Butte Limestone
Age (mya)
370 to 375
Muav Limestone
Bright Angel Shale
Tapeats Sandstone
525 to 530
530 to 540
540 to 545
Geological Time Scale
Era
Cenozoic
Mesozoic
Paleozoic
Period
Quaternary
Tertiary
Cretaceous
Jurassic
Triassic
Permian
Pennsylvanian
Mississippian
Devonian
Silurian
Ordovician
Cambrian
Precambrian
Years Before Present (mya)
Present – 1.6
1.6-66
66-144
144-208
208-245
245-286
286-320
320-360
360-408
408-438
438-505
505-570
570 - 4500
3. Use the line below to construct a time line showing the Grand Canyon rock layers listed on the previous
page. Before you being, think about the scale you should use – it should be even intervals!
350 mya
600 mya
                         
4. During which time period & era did the Temple Butte Limestone form?
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5. During which time period & era did the Tapeats Sandstone form?
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6. What environmental changes do you think happened between the formation of the Muav Limestone and the
Bright Angel Shale?
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7. What do you think happened between the formation of the Temple Butte Limestone and the Muav
Limestone that created a gap in time periods?
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