A useful index fossil must be
distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time
. Index fossils are the basis for defining boundaries in the geologic time scale
What are the characteristics of an index fossil quizlet?
Characteristics of index fossils:
Easily recognizable, short lived (found only in a few layers of rock worldwide), wide distribution (geographic range)
. A key example of an index fossil; a group of hard-shelled animals whose bodies had three sections, lived in shallow seas, and became extinct about 245mm years ago.
What makes a good index fossil quizlet?
What makes a good index fossil and why is it different from other fossils?
It is distinctive, widespread, abundant and limited in geologic time. They were only alive for a short amount of time.
What is the best index fossil?
The best index fossils are common, easy-to-identify at species level, and have a broad distribution—otherwise the likelihood of finding and recognising one in the two sediments is low.
Ammonites
fit these demands well, and are the best-known fossils that have been widely used for this.
What are the characteristics of a useful index fossil?
A good index fossil is one with four characteristics:
it is distinctive, widespread, abundant, and limited in geologic time
. Because most fossil-bearing rocks formed in the ocean, the major index fossils are marine organisms. That being said, certain land organisms are useful in young rocks and specific regions.
Will humans be a good index fossil?
Some fossils are more useful than others in establishing the age of rocks. These are called index fossils. …
It is possible that humans also will be good index fossils at some time in the distant future
. Humans have distinct hard parts, and we often bury our dead.
What are 3 considerations for choosing a fossil to correlating rocks?
To be considered an index fossil, it must meet 3 criteria:
The fossilized organism must be easily recognizable
. It must be easy to ID and look unique. 2. The fossils have to be geographically widespread, or found over large areas so that we can use them to match layers separated by huge distances.
What 3 main characteristics make a good index fossil?
A useful index fossil must be
distinctive or easily recognizable, abundant
, and have a wide geographic distribution and a short range through time. Index fossils are the basis for defining boundaries in the geologic time scale and for the correlation of strata.
What four characteristics are best for an index fossil to have quizlet?
The four main characteristics that make a fossil a good index fossil are that
the fossil is abundant, widespread, distintive and it has to be limited in geologic time
.
What is an index fossil and how is it used?
Keyed to the relative time scale are examples of index fossils, the forms of life which existed during limited periods of geologic time and thus are used as
guides to the age of the rocks in which they are preserved
.
What are the 5 types of fossils?
Five different types of fossils are
body fossils, molds and casts, petrification fossils, footprints and trackways, and coprolites
.
What is not a characteristic of index fossils?
Why are many fossils not considered index fossils? Because
if it is not widespread or huge time frame than hard to find
. Also organisms found all over the world – bc continent may have been connected. Why did Al Wegener choose the index fossils that he did to develop his ideas on Continental Drift?
How are index fossils beneficial to scientists?
Index fossils
help scientists to determine the approximate age of a rock layer and to match that layer up with other rock layers
. Fossils give clues about the history of life on Earth, environments, climate, geologic history, and other events of geological importance.
What is the most famous fossil?
Lucy, a 3.2 million year old Australopithecus afarensis
named after the Beatles' song “Lucy in the Sky with Diamonds”, is perhaps the most famous fossil in the world.
Which of the following is the best example of an index fossil?
Of the following organisms, the best index fossils would be:
a specific type of trilobite that existed for only a short geologic time in widespread geographic areas
.
Which index fossil is the oldest?
The law of superposition states that each
rock
layer is older than the one above it. So, the relative age of the rock or fossil in the rock or fossil in the rock is older if it is farther down in the rock layers.
