This era started off with what big expansion of marine life?
What is: the Cambrian explosion
What caused the Paleogene extinction event that wiped out 75% of plants and animals?
What is: A large meteorite
What law states that younger rock layers lie on top older deposits ?
What is : the Law of superposition
When was the formation of the earth’s crust
What is approximately 4 billion years ago
The worlds continents merged to form what landmass during the Permian period?
What is: Pangea
What is the period where the first birds and mammals began to appear?
What is: The Jurassic
When a fault cuts through a rock layer what can we tell about its age?
What is : younger
Microbial life first appeared during this eon
What is the Hadean Eon
During this era, what type of animal, classified by their hard exoskeletons and segmented bodies, dominated the oceans? Eg. Trilobites
What are: arthropods
During what period did the first flowering plants begin to appear?
What is: The Cretaceous period
what is the word for when rock layers match from one geologic location to another
What is : Correlation
The adirondack mountains are the result of this precambrian event
What is the last precambrian orogenies
This era ended after the Great dying. An event that killed what percent of terrestrial vertebrates?
What is: 70%
What ocean became fully formed during the Cretaceous period?
What is: The Atlantic Ocean
Mesozoic marine organisms with coiled shells that make great index fossils
What are: ammonites
The oldest continental rock
What is the craton
What is the pennsylvanian period also known as, due to its increased variety of insects?
What is: Age of cockroaches
What metal has been found in excess when dating earths layers, proving the theory of an asteroid extinction event at the end of the Mesozoic era?
What is: Iridium
what is the name for a deposit of sedimentary rock compressed into a layer
What is : strata
the oldest fossils found from the precambrian
What are stromatolites