Late Paleozoic ENG
Carboniferous and Permian are periods characteristic with the Variscan Orogeny within Europe. Continents Gondwana, Laurasia, and Northern America collided, creating a single one called Pangea. Towards the end of Permian, however, this supercontinent already stared to disintegrate again. The consequence of the collision was high mountain ridge including the Krkonoše Mts. In their foreland, several freshwater basins were formed, where material from the mountains was deposited. Hot climate constituted excellent environment for floras, and faunas as well. Especially for bivalves, gastropods, crinoids, corals, and other invertebrates, as well as fishes, sharks and the first reptiles. Lands were covered with large swamps with many species of wet-like vascular plants (arborescent horsetails, clubmosses, ferns and gymnosperms, which transformed into black coal beds. The Bohemian Massif was mountainous land with numerous active volcanoes, faults, and lakes. Deposits from the period covered large areas of our country. Local one called the Krkonoše Piedmont Basin contains freshwater siltstones, sandstones, and conglomerates, mostly red-brown and often with big amount of fossils. In many places, these rocks have been penetrating with lavas, especially during Permian. These volcanics called melaphyres, are known for their rich content of precious stones.