Geology of the Pacific Ocean . The Pacific Ocean developed from the Panthalassa, a vast global ocean, following the breakup of the supercontinent Pangaea in the Mesozoic Era, gradually forming Gondwana and Laurasia, which in turn divided. There is no firm date for when the changeover occurred, as the replacement of the sea bed is a continuous process, though reconstruction maps often change the name from Panthalassic to Pacific around the time the Atlantic Ocean began to open. The Panthalassic Ocean first opened around 750 million years ago at the breakup of Rodinia, but the oldest Pacific Ocean floor is only around 180 Ma old.
Gondwana Rainforests of Australia are divided into sections for listing on the Australian National Heritage List, from north to south, as below: Gondwana Rainforests The Gondwana Rainforests of Australia, formerly known as the Central Eastern Rainforest Reserves, are the most extensive area of subtropical rainforest in the world. Collectively, the rainforests are a World Heritage Site with fifty separate reserves totalling from to Brisbane. The Gondwana Rainforests are so-named because the fossil record indicates that when Gondwana existed it was covered by rainforests containing the same kinds of species that are living today. Not all Gondwanan rainforests in Australia are located in