Geologic Time Worksheet Axia W3D5
Use the following table to compare ways of evaluating geologic time. Your description, similarities, and differences must each be at least 50 words. |Time Evaluation Method |Description |Advantages of this Method |Disadvantages of this Method | |Relative dating |Relative dating is the process |There are a few advantages of |The disadvantage to relative | | |of estimating the order of |relative dating.
One is that |dating is that an exact time | | |events but not necessarily |this is an estimate of the age |cannot be given to a rock | | |determining when the events |of a structure. Meaning that |structure or fossil. This method| | |occurred.
When looking at rocks |there is room for error. This |is only an estimate and because | | |and fossils the deeper the |method is good if weathering or |of that the true time in which a| | |structure or fossil the older it|erosion is prevalent. Because |rock structure or fossil was | | |is.
During this process there is|some of the rock structure is |started or deposited cannot be | | |not exact age or date that is |missing or interrupted exact age|determined. | | |given to a rock or fossil only |would not be able to be found. | | | |an estimate of when it stated or| | | | |was alive. | | |Absolute dating |Absolute dating is a process in |The advantage to absolute dating|The disadvantage of absolute | | |which geologists or other earth |is that an exact age can be |dating is not every rock | | |scientists determine the |determined for a rock structure |structure or fossil’s exact age | | |specific age of a rock |or fossil. This is beneficial to|cannot be determined.
Depending | | |structure, fossil or other |scientists to help determine the|on where a fossil is found or | | |scientific site or structure. |age of the earth and the rock |what mineral make up the rock | | |Absolute dating allows a |structures it contains. |structure will determine if | | |numerical age to be determined | |absolute dating would be | | |for a fossil or strata. |appropriate. | In the following space, explain the role of fossils in developing the Geologic column. Your explanation must be between 200 and 300 words. The geologic column is the putting together all known strata and matching them up in chronological order. Fossils are an important factor when developing the Geologic column. Depending on if there are any fossils present in a sediment layer and if there are determining what the fossil is can help determine which eon all strata stated to form in.
The geologic column is divided to several different time frames. These time frames are referred to as eons, eras, periods and epochs. Most of the Earth’s existence can be separated into three eons. Each eon in earth’s existence lasted at least a hundred million years. The first two eons that earth existed fossils were very rare or hard to find. Those two eons are referred to as the Archean eon and the Proterozoic. The most recent area is referred to as the Phanerozoic eon. The Phanerozoic eon is the most recent eon and is the only eon that contains a lot of fossils.
Significant changes happened to the fossil assembly during the three eras that took place during the Phanerozoic eon. The three eras of the Phanerozic eon are Paleozoic, Mesozoic, and Cenozoic. These eras have been divided by significant extinction events. The era that is very important is the Paleozoic. This is because during this time was the first appearance of hard bodied animals that fossilize much better then soft bodied organisms.
Reference
- Murck, B. W. , Skinner, B. J. , & Mackenzie, D. (2010). Visualizing geology (2nd ed. ). Hoboken, NJ: Wiley.
