The Triassic Period

The sun beat down on the desert afternoon.  The ground was baked and cracked, and even the scattered clumps of ferns looked dusty in the heat.  In the distance, though, pine trees and cycads reached for the sky.  They surely surrounded a water hole.  A single predatory dinosaur sprinted in that direction.  Lunch would be found there! 

How the Earth Moved 
What the Weather Was 
What Was Growing 
How Do We Know That? 
Mesozoic Timeline

The Triassic period occurred during the first years of the Age of Dinosaurs, the Mesozoic Era.  The Triassic period spanned a period of time 248 million to 206 million years ago.  It was followed by the Jurassic period and the Cretaceous period.

How the Earth Moved  
The massive continent of Pangaea covered one quarter of the Earth’s surface during the early Triassic period.  At this time, Pangaea consisted of two parts:  Laurasia and Gondwana.  Laurasia was the northern part of Pangaea.  It included the land that would become North America, Europe and Asia.  Gondwana was Pangaea’s southern half.  It would eventually break up to form Africa, Australia, South America, and Antarctica. 

There was only one huge ocean during the Triassic period.  This ocean was called Panthalassa.  Panthalassa extended inland only in the narrow inlet of the Tethys Sea. 

Near the end of the Triassic period, the Earth was beginning to experience volcanic activity.  Forceful explosions began to create the valley that would become the Atlantic Ocean.  These eruptions also formed the rift that would begin the massive breakup of Pangaea during the Jurassic period.     
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What the Weather Was  
The world’s climate during the Triassic period was still and arid.  On the huge landmass of Pangaea, the climate was always hot, dry and desert-like everywhere except right along the coast.  There was no real difference in temperature anywhere on Earth, and no ice existed at the poles yet.  Oceanic currents and atmospheric winds were slow moving, leading to a stable, arid climate across the globe.
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What Was Growing  
The most common plants of the Triassic period were cycads (tall, palm-like trees), conifers and ginkgos.  Many different varieties of ferns and horsetails provided low vegetation cover for the ground.  Like most of the early Mesozoic Era, the plants of the Triassic period were all non-flowering plants that reproduced from seeds, cones or spores. 
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How Do We Know That?  
The Triassic period is named after triple-layered samples of rock found in Germany.  The rock samples are made of layers of sandstone, limestone and copper-bearing shale.  These layers are very typical of Triassic age rocks.  Although Triassic rocks have been found all over the world, the thickest sample was found in the Alps.  This particular section of rock measured about 25,000 feet (7,500 meters) thick. 
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Mesozoic Timeline

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