Mesozoic ENG

Mesozoic spanned over almost 200 million years. It is divided into Triassic, Jurassic, and Cretaceous. 

Triassic

The great continent called Pangea disintegrated, and the area of the Bohemian Massif moved further northward. After the huge extinction at the end of Paleozoic, Triassic fauna was considerably less varied. In the sea, there were a lot of ammonoids and molluscs, while on land the development of vertebrates continued and the first dinosaurs appeared. In our country, Triassic rocks, especially whitish fine-grained sandstones, are found on the northeastern edge of the Krkonoše Piedmont Basin near Červený Kostelec. They are known for rare content of dinosaur footprints. 

Jurassic

Jurassic is a period characteristic with progressive evolution of ammonites, belemnites, sea urchins, etc. The dinosaurs were dominant on the land and often reached gigantic size. The Jurassic period is beginning of first mammals also. However, with their size equalling a rat, they were a minor part of the fauna. At the end of Jurassic, the oldest birds appeared. In our country, Jurassic rocks are rare. 

Cretaceous

Towards the end of Mesozoic, northern continent Laurasia collided with southern Gondwana, resulting in the big Alpine orogeny. The Bohemian Massif was marginally influenced only. As a result of a massive greenhouse effect, the global climate was very warm, and the sea level reached several hundred metres higher above present. The sea repeatedly flooded our country and left thick beds of deposits here, mostly pale, fine-grained sandstones. The shallow sea was home to many kinds of fauna, e.g. mosasaurs, fishes, sharks, giant ammonites, bivalves, oysters, and sponges as well. Land fauna was represented by various kinds of dinosaurs, as well as mammals. Moreover, first Angiosperms (flowering plants) appeared and quickly colonized the land. Cretaceous deposits cover large areas of our country, they are well known for rock towns formed by erosion of the latter.