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44 Cards in this Set

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  • Back
What are stromatalites?
fossil reefs common during the Precambrien that were once made of algae and tiny bacteria
Why are jellyfish not preserved as fossils?
They have such soft bodies that there are no hard parts left to fossilize
What was the early atmosphere like?
It had NO free oxygen.
What became extinct at the end of the Paleozoic era?
* nearly half of all known animal groups became extinct

~ trilobites, eurypterids, seed ferns, scale trees, conifers
Which modern land areas were affected by the Permian Ice Age?
South America, Australia, South Africa, and India
What is the most important difference between Precambrien rocks and Paloezoic rocks?
The Precambrien rocks contain few fossils while the Paleozoic rocks contain abundant fossils
The first birds appeared during which era?
The Mesozoic Era
Ammonites are....
...index fossils of the Mesozoic Era.
The Cenozoic is the Age of ___________.
Laurasia consisted of ......
the future North America and Eurasia.
The two periods of the Cenozoic are.....
the Tertiary and the Quaternary
The two main factors that distinguish hominids from other primates are...
..bipedal movement (walking upright on two legs) and brain size
What is the evidence of a mild Mesozoic climate?
...corals in Europe
The largest dinosaurs were the.....
...sauropod dinosaurs
The Canadian ________ is the exposed part of the North American craton.
The _________ Period is known as the Age of Fishes b/c the number and variety of the fish in the fossil reocrd.
Devonian Period
Mesozioc time is divided into three periods.....
-Triassic, Jurassic, and Cretaceous.
Precambien time is what?
* All geologic time before the start of the Paloezoic Era.

~ includes the time span between the orgin of the Earth and 570 million years ago.
Precambrien rocks contain about half the world's what?
metallic mineral deposits
Identify some locations in North America where Precambrian rocks can be seen.
...the bottom of the Grand Canyon, in the core of the Rocky Mountains, in New York City, and the Piedmont region.
What mountains were formed by the Taconic Orogeny?
the Green Mountains of Vermont and the Tactonic Mountains in New York State
The largely unknown past before the Cambrian Period is referred to as the...
Precambrian Era
Which era is considered the Age of Reptiles?
...the Mesozoic Era
What are the sea scorpions that appeared during the Silurian Period called?
What is the most common Cambrian fossil? (It is crab-like in form.)
__________ are a large group of terrestrial reptiles common during the Mesozoic era.
_______ is the oldest era which began when Earth was first formed, between 4 and 5 billion years ago: the earliest known rocks formed during this era
Archean Era
_________ is the second oldest era which began about 2.5 billion years ago: evidence of simple plants and worms who lived in the ocean have been found in fossils in rocks from this time period
Proterozoic Era
________ is the third oldest era which began about 570 million years ago; contains fossils of both land and ocean plants and animals
Paleozoic Era
________ is the fourth oldest era which began about 250 million years ago; age of the dinosaurs/reptiles
Mesozoic Era
_________ is the youngest era which began about 65 million years ago and is still going on today; new evidence is the Ice Age and the appearance of humans
Cenozoic Era
No land-living animals are known for either the ___________ or the Ordovician.
the Cambrien era
The Cenozoic Era is divided into _______ periods and _______ epochs.
two periods and seven epochs
Cenozoic invertebrates that lived in the ocean....
...were nearly the same as marine invertebrates of today.
What mountain ranges or other features were formed or raised in the Cenozoic Era?
..the Cascades, the Himalayas, the Rockies, the Grand Canyon, the Sierra Nevadas, and the Alps
What does the Law of Superposition say?
“in a sequence of undisturbed (that is, not overturned) sedimentary rocks, the oldest rocks will be at the bottom and the younger rocks will be at the top”
What does the Law of Cross-Cutting Relationships say?
"an igneous rock is younger than the rocks it had intruded, or cut across”
What does the Law of Included Fragments say?
“the pieces of one rock found in another rock must be older than the rock in which they are found”
Absolute time is....
...a method of recording events that identifies the actual date of an event
Relative time is...
...the method of recording events in a time sequence by comparing the event with other events; does not identify actual date of occurrence
The largest dinosaurs lived during the ____________.
...Cretaceous Period.
The dinosaurs dominated Earth for ____________ years.
...160 million years.
What was the Tethys Sea?
A large bay that separated what are now the continents of Africa and Eurasia.
What was Gonwanaland?
It was the remainder of the countinents left over from the formation of Laurasia. It was in the southern part of the world.