the Sudetes but also parts of the Sudetic foreland being part of a SW-NE oriented Bohemo-Silesian Belt of volcanic rocks. Mantle xenoliths have been recovered from the lavas of a volcano at Ještěd-Kozákov Ridge in the Czech western Sudetes. These pyroxenite xenoliths arrived to surface from approximate depths of 35, 70 and 73 km and indicate a complex history for the mantle beneath the Sudetes. There are thermal springs in the Sudetes with measured temperatures of 29 to 44 °C. Drilling has revealed the existence of waters at 87 °C at depths of 2000 m. These modern waters are believed to be associated to the Late Cenozoic volcanism in Central Europe. Uplift and landforms The Sudetes forms the NE border of the Bohemian Massif. In detail the Sudetes is made up of a series of massifs that are rectangular and rhomboid in plan view. These mountains corresponds to horsts and domes separated by basins, including grabens. The mountains took their present form after the Late Mesozoic retreat of the seas from the area which left the Sudetes subject to denudation for at least 65 million years. This meant that during the Late Cretaceous and Early Cenozoic 8 to 4 km of rock was eroded from the top of what is now the Sudetes. Concurrently with the Cenozoic denudation the climate cooled due to the northward drift of Europe. The collision between Africa and Europe has resulted in the deformation and uplift of the Sudetes. As such the uplift is related to the contemporary rise of the Alps and Carpathians. Uplift was accomplished by the creation or reactivation of numerous faults leading to a reshaping of the relief by renewed erosion. Various "hanging valleys" attest to this uplift. Block tectonics has uplifted or sunken crustal blocks. While the Late Cenozoic uplift has uplifted the Sudetes as a whole some grabens precede this uplift. Weathering during the Cenozoic led to the formation of an etchplain in parts of Sudetes. While this etchplain has been eroded various landforms and weathering mantles have been suggested to attest its former existence. At present the mountain range shows a remarkable diversity of landforms. Some of the landforms present are escarpments, inselbergs, bornhardts, granitic domes, tors, flared slopes and weathering pits. Various escarpments have originated from faults and may reach heights of up to 500 m. To the northeast the Sudetes is separated from the Sudetic foreland