Shallow gas accumulations and gas seepage may indicate deeper hydrocarbon reservoirs. Sonar and high resolution seismic recordings were carried out to obtain gas migration and accumulation below seabed in Northeast Persian Gulf. Results revealed some structures and reflectivity effects, for example few pockmarks, gas seepage, and other surface structures in sonar and seismic data. Most of the features observed on seismic data were located at depths between 5 and 10 m (sub-sea bed) that include acoustic blanking and turbidity, gas packets, gas chimneys, and enhanced reflection. Most of the gas is accumulated on young and thin parallel layers, but the presence of acoustic effect in Aghajari Formation indicates that the origin of the gas accumulation in shallow strata may be located in a deeper reservoir.

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