The Vienna basin is a subsidence zone between the Alps and the Carpathians. The basin filling of Neogene age with thicknesses up to 5,000 m is underlain by tectonic units. These are the nappes of the Limestone Alps and the Flysch. Below these tectonic units are the so-called autochthonous sediments and finally the basement. Thickness of this sediment pile can be much greater than 10,000 m. Oil and gas reservoirs exist in all geologic units.

All the crude oils from the Vienna basin belong to 1 major family. Only a single oil exists in the underground of the Molasse; all the other oils from the Molasse zone and the Flysch zone belong to the major family.

Sediments of Upper Jurassic age from the autochthonous Mesozoic are the source for the major oil family. The main phase of oil generation occurs in depths about 4,000 m to 6,000 m. In greater depths this oil source is also a good gas source. Only a few other horizons are able to generate gas, but only lower amounts. Thus, only 1 main source rock for all hydrocarbons, oil and gas, exists in the Vienna basin. The various burial histories of this sediment around the Vienna basin divide this area into regions of different exploration value.

From the geologic point of view, this major source rock can also be found under the Alps. Therefore, the exploration of deep targets along the northern edge of the Alps and under the Alps gets a more positive aspect.

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