Why Devonian could not be considered an index fossils?
How can the occurrence of fossils and their known age ranges be used to date rocks?
Need help by understanding the question.
9 answers
What does your text say about dating rocks, index fossils, and the Devonian period?
Fossil Occurrence and the Age of Rocks:
Groups of fossil organisms occur throughout the geologic record for specific
intervals of time. This time interval is called the fossil’s range. Knowing the
range of the fossils of specific organisms or groups of organisms can be used
to relatively date rocks and sequences of rocks. In this laboratory exercise,
you will use such information to assign a date to a hypothetical unit of rock.
Groups of fossil organisms occur throughout the geologic record for specific
intervals of time. This time interval is called the fossil’s range. Knowing the
range of the fossils of specific organisms or groups of organisms can be used
to relatively date rocks and sequences of rocks. In this laboratory exercise,
you will use such information to assign a date to a hypothetical unit of rock.
The text above^^ is for this question: How can the occurrence of fossils and their known age ranges be used to date rocks?
Fossils died at the same time the rocks were formed.
I still don't understand.
how? why?
Please read about the three different kinds of rocks.
http://www.kidsloverocks.com/html/types_of_rocks.html
http://www.kidsloverocks.com/html/types_of_rocks.html
okay, and how about this question. Why Devonian could not be considered an index fossils?
I'm sorry, but I don't know. Perhaps if you read this site carefully, you'll find the answer.
http://www.britannica.com/science/Devonian-Period
http://www.britannica.com/science/Devonian-Period