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Cenozoické vulkanické série v západní části Českého masívu
Ulrych, Jaromír ; Novák, Jiří Karel ; Lloyd, F. E. ; Balogh, K. ; Hegner, E. ; Viereck-Götte, L. G.
The western part of the Ohře/Eger Rift is a geodynamically active area in the Alpine foreland. Associated Cenozoic alkaline volcanism, particularly that of Quaternary age, plays an important role in the seismic active region of the W Bohemia and Saxony and is accompanied by intensive manifestations of mantle degassing (CO2, He, N). Three Tertiary to Quaternary alkaline volcanic rock series were recognised there: 1. Early Oligocene to Early Miocene (31-20 Ma) in the Doupovské hory Mts. and western Ohře Riftu. 2. Middle to Late Miocene (16-8 Ma) associated with the Cheb-Domažlice Graben. 3. Pleistocene (0.43-0.26/0.11 Ma) associated with the Ohře Rift and Cheb-Domažlice Graben junction. On the basis of isotopic and geochemical data of the primitive mafic volcanics of all series the source of magmas is a sublithospheric HIMU mantle source.
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