How deep is the unconventional resource play in Jurassic Mikulov marls beneath the Czech part of the Vienna basin?

The oil-gas charge systems of the Vienna basin are mostly associated with the Jurassic source rocks, which lower portion, can be considered as unconventional resource play. For estimations of hydrocarbon generation potential of Jurassic marls from the Mikulov Formation of the Czech part of the Vienna basin the Rock Eval pyrolysis was performed for 7 samples collected from 5 exploratory wells at depth in range from 3173 m to 4551 m. Vitrinite relectance data have been used to differentiate maturity levels and to delineate depth of gaswindow zone, wherein fractured marls of Mikulov Formation may be overpressured because of sedimentary loading and recent tectonic stresses. One of the reasons to consider this option is the fact that this peliticcarbonatic unit at the deep levels is tectonically enlarged by multiple duplications. Such kind of structural thickening related with thrust cleavage duplexes occur in the Marcellus Shale, which is up to now the most successful exploration reservoir for commercial shale gas production.