AVO technology has successfully detected hydrocarbon reservoirs for more than two decades. However, AVO is not the master key for unlocking the identity of lithology and pore fluid for every reservoir. There are still problems that the existing AVO technology doesn't handle adequately, thus new AVO technology is often introduced by combining two different techniques. We are proposing such a combination. Thin-bed amplitude spectra and angle-dependent reflection amplitude are related to pore-fluid content by crossplotting frequency slices from spectral decomposition cubes at two different incident angles.