Supercontinent that of today by as much as 6–10 degrees and mid-latitudes in the winter were less than −30 degrees Celsius. These seasonal changes within the supercontinent were influenced by the large size of Pangaea. And, just like today, coastal regions experienced much less variation. During the Jurassic, summer temperatures did not rise above zero degrees Celsius along the northern rim of Laurasia, which was the northernmost part of Pangaea (the southernmost portion of Pangaea was Gondwana). Ice-rafted dropstones sourced from Russia are indicators of this northern boundary. The Jurassic is thought to have been approximately 10 degrees Celsius warmer along
Geology of the North Sea zone. The Triassic saw active crustal stretching via the rifting process, lower sea levels and volcanic activity. As the Jurassic (200–145 Ma) started, Pangaea began to break up into two continents, Gondwana and Laurasia. At this time sea levels rose. The burial of algae and bacteria below the mud of the sea floor during this time resulted in the formation of North Sea oil and natural gas, much of it trapped in overlying sandstone by deposits formed as the seas fell to form the swamps and salty lakes and lagoons that were home to dinosaurs. Volcanism and a rift system