What are Igneous, Metamorphic, and Sedimentary rocks?
200
These fossils are more useful than normal fossils, because they lived for a shorter period of time and are found all over the world.
What are Index fossils?
200
This is the difference between Limestone and Sandstone.
What is calcium carbonate?
300
The Dinosaurs died in this era.
What is the Mesozoic era?
300
this was discovered 5,000 years ago
What is the first written history
300
These rocks probably won't contain fossils.
What are Igneous and Metamorphic rocks?
300
These rocks go back millions of years and show how the CO cut through the ______ ______.
Why are the Grand Canyon rocks important?
300
This holds minerals together to form layers
What is matrix?
400
This era includes the Tertiary period.
What is the Cenozoic era.
400
These appeared 90,000,000 years ago
What is bees
400
This type of rock forms and changes underground.
How do metamorphic rocks form?
400
The GC is mostly composed of this type of rock.
What is sedimentary?
400
These types of rocks in the grand canyon are important to geologist.
What are index fossils?
500
There are these many eras.
What is the number 4?
500
This organism created oxygen. It was alive about 3.5 billion years ago.
What are Stromatolites?
500
Igneous rocks form here.
What is slowly underground?
500
This is the process is finding relationships between rock layers from different locations. By comparing rock samples from different eras, we can see that the sequence of rock layers is the same as the Grand Canyon and the plateau.