Absolute Dating, Law of Superposition

Layers of rock can tell us a lot about the history of an area. The most accurate way to date rock is using the law of superposition.

• True
• False

Absolute Dating is a more accurate way to date fossils and rock layers because it uses radioactive elements to tell the exact age of dead organisms in those layers. What is the name of the popular radioactive element that scientists use to measure this.

• Uranium
• Potassium
• Carbon 13
• Carbon 14

Use the diagram and relative dating to determine what is the oldest layer. 

• The bottom layer will contain the oldest fossils
• The top layer will contain the oldest fossils
• It is impossible to tell which layer contains the oldest fossils with out absolute dating
• Layer A and C contain fossils from the same period

Use the diagram and the law of superposition to make a statement about the image. 

• The bottom two layers are generally the same age range
• The bottom layer is most likely the oldest and the top layer is most likely the youngest
• The top two layers cannot be determined because of weathering and erosion that may still be occuring

The attached image shows the Grand Canyon. The Unkar Group shows an areas where there may have been some folding and faulting. Choose the best answer to explain what impact this may have on dating the fossils in this layer.

• This may cause items dated in this layer to be incorrectly dated if the scientist only uses relative dating.
• Scientists must take into consideration the folding and faulting that is happening in this image when dating the layers.
• The most accurate way to date this layer of rock would be to use absolute dating.
• The most accurate way to date the fossils would be to use the Law of Superposition

Ms. Felder decides to climb a mountain for fun.  When she gets to the very top she looks down and sees a group of shells and notices the fossil of what looks like a fish.  How does she explain this?

• She takes the fossils to a fellow scientist for absolute dating
• She knows that some marine fossils are found on top of mountains because of plate that have converged 
• She knows that some marine fossils are found on top of mountains because of plate boundaries that are divergent
• She uses relative dating to try to determine how old the fossils are. 

Sometimes sea shells can be found in strange places.  Like deserts and on mountains. Other than plate boundaries moving what is another reason for this?

• The earth's tilt on its axis has changed over the years and the equator use to be farther south
• Sea levels use to be much lower 
• Plate boundary movement is the only correct explanation for marine fossils in strange places
• The sea levels use to be much higher and covered most of the land on earth. So marine fossils are found in places far from water

Which rock cycle process follows weathering and erosion?

• Sedimentary Rock Formation
• Compaction and Cementation
• Deposition
• Heat and Pressure

Which type of rock leads to melting, weathering and erosion, and heat and pressure.

• Sedimentary
• Igneous
• Metamorphic
• Biological

Which type of rock is always formed after the process of compaction and cementation?

• Metamorphic
• Sedimentary
• Igneous
• Obsidian