f The comparative test of AVO and AVD methods on gas and oilfields

The AVO (amplitude versus offset) and AVD (attenuation and velocity dispersion) methods are based on seismic effects caused by the presence of hydrocarbons in pores. It means that both methods are used as a direct detection of hydrocarbons. The results of successful applications of AVO on gas fields are widely known. Theoretically the method should work on oil field if there is a gas contact above oil reservoir but it had never been tested in case of a clean oil contact. The results of successful applications of AVD method on oil fields also were published [1-3]. At the same time this method was not tested on purely gas fields.