f Detection of shallow gas accumulations and uncontrolled gas flow by means of velocity and AVO analysis

Two seismic reflection profites (50 and 20 km long) were shot over several hydrocarbon reservoirs in Middle Miocene to Upper Pliocene sequences in south-eastern Hungary. Here the basement which forms an anticline is made up of four clearly distinguishable zones of NW-SE strike. The four units of the anticline consist of mesozoic rocks, metamorphic rocks, mesozoic rocks again, and granite. The anticline is surrounded by two large depressions in which great mass of source rock is known. From these rocks hydrocarbon migration occured.