Geology Test Review #3 - Chapter 9

Finding several species of fossils, rather than just one, in the same rock layer is more useful to geologists because:

It indicates the sediments must have been deposited at the same time when all the species were present.

Who came up with the concept that geologic processes operating at present are the same processes that operated in the past?

James Hutton

Which of the following time periods were dinosaurs the dominant creatures?

Mesozoic

Which principle of relative dating can be used at Siccar Point in Scotland to determine that the rocks below the unconformity were tilted to vertical before erosion occurred?

Original horizontality

In which of the following time periods did coral, clams, fish, plants and insects become abundant?

Palezoic

Which of the following chapters in geologic time occurred before there were abundant animals with hard parts?

Precambrian

Which of the following is the earliest (oldest) chapter of geologic time?

Precambrian

The oldest rocks and minerals on Earth's surface have been found in Canada and Australia and are from the:

Precambrian Era

What is a possible cause of the extinction event called the Great Dying?

a great outpouring of lava at the end of the Paleozoic

What was the Cambrian explosion?

a time when many different types of creatures appeared on Earth

The first organisms on Earth included:

algae

The geologic timescale details and divides geologic time based upon:

fossil data

Groundwater can be dated using:

isotopes

Which of the following is NOT something we can learn by determining isotopic ages?

we can determine all of these

In which of the following time periods were mammals the dominant type of life?

Cenozoic

The oldest known rock found on Earth is dated at:

over 4 billion years old

What is a principle we use to determine the age of a landscape surface?

A surface with a well-developed soil is probably older than a surface with no soil

Which factor would help ensure survival of one species over another?

Adaptable to environmental change

Which of the following is NOT a way in which fossils can be preserved?

All of these are ways a fossil can be preserved

If a rock started with 1,000 atoms of a parent but now contains 250 atoms, how many half lives have passed?

2 half lives

How did an oxygen-rich atmosphere develop from a carbon dioxide-rich atmosphere?

Through photosynthesis by cyanobacteria

For which of the following resources do geologic areas help us explore?

all of these

To what does the term evolution refer?

all of these

What strategies do we use to investigate human origins?

all of these

What types of life developed during the Paleozoic?

all of these

Which of the following forms different layers from season to season and can be used to determine how many years the layers represent?

all of these

Which of the following is a reason why rock units may change from one section to another?

all of these

Which of the following is evidence that Earth's history is not short?

all of these

Which of the following materials can be dated with carbon-14 at archaeology sites?

all of these

Isotopes that decay slowly are used to date:

ancient rock

In geology, determining time equivalency in rocks is called:

correlation

Which principle can be used to determine the relative age of an igneous intrusion called a dike?

cross-cutting relations

Which of the following features look like fossils but are not?

dark minerals that grow in branching patterns

Which is the last step in formation of a typical landscape?

erosion

The term half life represents the time it takes:

for half of the parent atoms to decay into daughter atoms

What were some of the earliest forms of life on Earth?

microscopic creatures that built mound-shaped structures called stromatolites

Which type of unconformity is produced when layers of sandstone and conglomerate bury an eroded surface of an igneous or metamorphic rock?

nonconformity

How does an angular unconformity form?

older rocks are tilted, eroded, and overlain by younger rocks

A hypothesis that explains how new organisms or new characteristics can appear suddenly in the fossil record is called:

punctuated equilibrium

Which fossils provide information as to the mode of formation of an oxygen-rich atmosphere by about 2 billion years ago?

stromatolites

Which principle is used to determine the age of rocks by ordering them from oldest on the bottom to the youngest on the top?

superposition

Early Earth would have been inhospitable to many life forms of today because:

the atmosphere lacked oxygen

Some fossil species are of little value to geologists for correlation because:

they existed for a long period of geologic time

What defines the boundaries between each of the three eras in the geologic timescale?

two great mass extinctions

Missing geologic time caused by erosion is called a (an):

unconfirmity

What factors are the most critical in determining whether a fossil is preserved?

whether the creature had hard parts and how fast it was buried