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46 Cards in this Set

  • Front
  • Back
Scientists assign relative ages by using

potassium-argon dating
the ratios of isotopes
the principle of superposition
radioactive half-lives
The principle of superposition
Rock layers cut by a fault formed

before the fault
after the fault
at the same time as the fault
cannot be determined
before the fault.
If the half-life of an unstable element is 5,000 years, what percentage of the parent material will be left after 10,000 years?
100% 75% 50% 25%
25%
Geologists would use ___ to determine the most accurate and precise age of Earth's oldest rocks.

relative dating uranium-lead method
carbon 14 method index fossils
the carbon-14 method
According to geologists, the Earth is approximately

1,000 years old. 5,000 years old.
2.5 million years old.
4.6 billion years old.
4.6 billion years old.
Geologists would use ___ to determine the most accurate and precise age of Earth's oldest rocks.

relative dating uranium-lead method
carbon 14 method index fossils
the carbon-14 method
The phrase "younger over older" can be used to remember the principle of__.
absolute dating
unconformities
superposition
geologic columns
superposition
The principle of __ states that the same geologic processes shaping the Earth today have been at work throughout Earth's history.
uniformitarianism gradualism
catastrophism none of the above
uniformitarianism
The principle that states that all geologic change occurs suddenly is called

gradualism uniformitarianism
catastrophism none of the above
catastrophism
The principle of __ states that the same geologic processes shaping the Earth today have been at work throughout Earth's history.
uniformitarianism gradualism
catastrophism none of the above
uniformitarianism
Determining whether an object or event is older or younger than other objects or events is called

absolute dating relative dating
radiometric dating none of the above
relative dating
*refer to the picture card
Which of the following would most likely be used to determine the relative age of each rock layer?
the geologic column superposition
faults all of the above
All of the above
Missing rock layers that create gaps in rock-layer sequences are called

intrusions folds
uniformities unconformities
unconformities
Which process might create unconformities in rock layers?
1) nondeposition of sediments
2) deposition of sediments
3) erosion of sediments
4) both 1 and 3
Both nondeposition of sediments and erosion of sediments might create unconformities. (both 1 and 3)
Which of the following is a type of unconformity?

angular unconformity disconformity
nonconformity all of the above
all of the above
A(n) ___ exists between horizontal rock layers and rock layers that are tilted or folded.

angular unconformity disconformity
linear unconformity nonconformity
angular unconformity
Refer to picture **rock layers
To determine the relative age of rock layers 1-3, you could use the principle of
uniformitarianism catastrophism
superposition none of the above
superposition
Refer to picture **rock layers
Rock layers 4-6 have been distrurbed by

faulting intrusion
folding tilting
folding
Refer to picture **rock layers
The boundary labeled A represents a type of unconformity that is often hard to see called a(n) ___.
angular unconformity a disconformity
a nonconformity none of the above
a disconformity.
Refer to picture **rock layers
Which type of unconformity does the boundary labeled B represent?
disconformity angular unconformity
nonconformity all of the above
angular unconformity
Refer to picture **rock layers
What could you conclude if layer 3 contains reptile fossils and layer 5 contains anphibian fossils?
Reptiles existed before amphibians.
Amphibians existed before reptiles.
Amphibians existed before reptiles.
One-fourth of an ivory carving's original carbon-a4 remains unchanged. Carbon 14 has a half-life of 5,730 years. How old is the carving?
1,432.5 years 4,297.5 years
5,730 years ll,460 years
11,460 years
Refer to picture **rock layers
What could you conclude if layer 3 contains reptile fossils and layer 5 contains anphibian fossils?
Reptiles existed before amphibians.
Amphibians existed before reptiles.
Amphibians existed before reptiles.
Which of the following is NOT a medium in which organisms fossilize?

amber a glacier
tar ocean water
ocean water
___ of an organism occurs when its tissues are completely replaced by minerals.
Mummification Permineralization
Petrification Freezing
Permineralization
Insects can be preserved in ___ or hardened tree sap.
amber
ice
tar
coprolite
amber
The remains of organisms that have died in dry places are preserved through a process known as __.
mummification permineralization
petrification freezing
mummification
The ___ is characterized by the first land-dwellers - plants and amphibians.

Cenozoic era Paleozoic era
Mesozoic era Hadean eon
Paleozoic era
The ___ is known a the Age of Reptiles.

Cenozoic era Hadean eon
Paleozoic era Mesozoic era
Paleozoic era
The ___ is know as the Age of Mammals.

Cenozoic era Mesozoic era
Hadean eon Paleozoic era
Cenozoic era
A tribolite was buried by ocean sediment, leaving a cavity, or ___.

cast or mold
mold
Erosion is a major cause of the missing rock layers known as ___.

superposition or unconformities
unconformities
___ occurs when rock layers bend and buckle from Earth's internal forces.

folding or faulting
folding
___ is a principle that states that younger rocks lie above older rocks in undisturbed sequences.

Crosscutting or Superposition
Superposition
The time it takes for one-half of a radioactive sample to decay is called
a(n) ___.
half-life
A ___ is any naturally preserved evidence of life.
fossil
Preserved feces, or dung, from animals are called ___.
coprolite
___ are fossils of organisms that lived during a relatively short, well-defined time span.

Index fossils or Trace fossils
Index fossils
The first reptiles are associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Paleozoic era
The appearance of the first fish is associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Paleozoic
The appearance of the first horses is associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Cenozoic
The appearance of the first humans is associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Cenozoic
The appearance of the oldest life forms is associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Precambrian
The appearance of animals with no backbones is associated with which of the following eras?

Cenozoic Mesozoic
Paleozoic Precambrian
Precambrian era
In which of the following eras did no land animals exist?

Cenozoic Mesozoic
Paleozoic Precambrian
Precambrian
In which era did dinosaurs dominate the Earth?

Cenozoic Mesozoic
Paleozoic Precambrian
Mesozoic Era