Question 1

______ first pointed out that fossil species succeed one another through successive layers of sediment in a predictable order.

Accepted Answer

W.S. Smith, also known as William Smith, is credited with the principle of faunal succession, which states that fossil species succeed one another in a definite and recognizable order through sedimentary layers.

Question 2

When marine geologists collects a core of undeformed ocean-floor sediment,they know that the youngest layer is on the top of the core and the oldest is at the bottom because of the principle of __.

Accepted Answer

The principle of superposition states that in an undeformed sequence of sedimentary rocks, each layer is younger than the one below it and older than the one above it. This principle allows marine geologists to determine the relative ages of different layers of sediment in a core sample by analyzing their position within the core from top to bottom.

Question 3

The principle of ___ states that an original sedimentary layer extends laterally until it tapers or thins at is edges.

Accepted Answer

The principle of lateral continuity states that an original sedimentary layer extends laterally until it tapers or thins at its edges. This means that the layer was originally continuous, but erosion or other factors may have caused it to be discontinuous in certain areas.

Question 4

The _______ Era is the Age of Mammals.

Accepted Answer

The Cenozoic Era began about 65 million years ago and is also known as the Age of Mammals, as this is when mammalian life diversified and flourished. The other eras listed (Archean, Mesozoic, Paleozoic, Precambrian) were much earlier in Earth's history and did not have the widespread presence of mammals.

Question 5

In geology,_____ usually means determining time equivalency of rock units.

Accepted Answer

Correlation is the process of determining time equivalency of rock units. It involves comparing the characteristics of different rock units in different locations to determine if they are equivalent in age. This can be done through various methods such as stratigraphic layering, index fossils, and isotopic dating. Physical continuity and lateral continuity refer to the spatial extent of rock units, while unconformity and superposition refer to the geological processes that affect the formation and arrangement of rock layers.

Question 6

When the ____ came to a close,dinosaurs became extinct.

Accepted Answer

The Mesozoic Era is known as the "Age of Dinosaurs," and it ended with a mass extinction event, which wiped out the dinosaurs. The Holocene Epoch is the current geological epoch, and the Cenozoic Era is the age of mammals that followed the Mesozoic. The Precambrian and Paleozoic Eras are much earlier in Earth's history and are not relevant to the extinction of the dinosaurs.

Question 7

The _____ is the principle says that the same processes and natural laws that operated in the past are those we can actually observe or infer from observation as operating at present.

Accepted Answer

The answer of The _____ is the principle says that...

Question 8

Isotopic dating has shown that the Precambrian took up ______% of all geologic time.

Accepted Answer

Isotopic dating has shown that the Precambrian era, which encompasses the time from the formation of the Earth about 4.6 billion years ago to the start of the Cambrian period about 541 million years ago, took up about 87% of all geologic time. This era represents the vast majority of Earth's history.

Question 9

The Earth's largest mass extinction coincides with _____ in Siberia.

Accepted Answer

The Earth's largest mass extinction is known as the Permian-Triassic extinction event, which occurred around 252 million years ago. This extinction event coincides with massive volcanism in Siberia, known as the Siberian Traps. The volcanic activity released large amounts of greenhouse gases and caused significant climate change, leading to the extinction of up to 96% of marine species and 70% of terrestrial vertebrate species.

Question 10

Our ability to assign an age to geological and archaeological materials is based on our ability to measure the relative abundance of radioactive ___ and their stable decay products.

Accepted Answer

The ability to assign an age to geological and archaeological materials is based on radioactive isotopes and their stable decay products. This is because radioactive isotopes decay over time at a known rate, and by measuring the ratio of the radioactive isotope to its stable decay product we can determine how much time has elapsed since the material was formed.

Question 11

The Earth is approximately _____ years old.

Accepted Answer

The age of the Earth is estimated to be between 4.5 billion and 4.6 billion years old, based on radiometric dating of rocks and meteorites.

Question 12

The half-life of the carbon 14 isotope is 5730 years.If there were 4 billion atoms of C-14 in a particular organism at the time it died,how many atoms of C-14 would there be in the remains of that organism 11,460 years after it died?

Accepted Answer

The answer of The half-life of the carbon 14 isotope...

Question 13

The ___ of a radioactive material is the time it takes for a given amount of radioactive isotope to be reduced by half.

Accepted Answer

The definition given in the sentence matches only with the concept of "half life" which is given in option E.

Question 14

Alvarez and others proposed a hypothesis that dinosaur extinction occurred because __.

Accepted Answer

The Alvarez hypothesis proposes that one or more asteroids impacted Earth, resulting in environmental change such as fires, tsunamis, and a "nuclear winter" effect that caused global cooling and inhibited photosynthesis, ultimately leading to the extinction of dinosaurs.

Question 15

The ___ Era began with the appearance of complex life,as indicated by fossils like trilobites.

Accepted Answer

The Paleozoic Era is known as the "Age of Ancient Life" and began with the appearance of complex life, such as trilobites, around 541 million years ago.

Question 16

The relative-dating principle of __ states that fragments included in a host rock are older than the host rock.

Accepted Answer

The principle of inclusion states that fragments included in a host rock are older than the host rock. This is because the fragments must have existed before the host rock formed in order to be included within it.

Question 17

_____ are subdivisions of eras.

Accepted Answer

Periods are the subdivisions of eras in geologic time. Ages are subdivisions of periods, eons are the longest units of time, intervals typically refer to shorter periods of time, and formations are specific units of rock within a period or era.

Question 18

______ denotes the vast amount of time that precedes the Paleozoic Era.

Accepted Answer

The Precambrian spans from the formation of the Earth, about 4.6 billion years ago, to the start of the Paleozoic Era, about 541 million years ago. Therefore, the Precambrian denotes the vast amount of time that precedes the Paleozoic Era. Mesozoic, Paleozoic, Quaternary, and Cenozoic are all eras that follow the Precambrian.

Question 19

The _____ ended with the greatest mass extinction ever to occur on Earth.

Accepted Answer

The greatest mass extinction ever to occur on Earth occurred at the end of the Paleozoic Era. This extinction event is known as the Permian-Triassic extinction event, and it resulted in the extinction of over 90% of marine species and over 70% of terrestrial species.

Question 20

The ____ is based upon the observation that fossil species succeed one another through layers in a predictable order.

Accepted Answer

The principle of faunal succession says that fossil species succeed one another through layers in a predictable order.

Quiz 8: Time and Geology