Slow wave in the anisotropic liquid layer modeling a collector

Velocity and attenuation of slow wave propagating in the anisotropic liquid layer sandwiched between two elastic half-spaces are discribed. The liquid layer consist of the alternating liquid layers: water-oil, water-gas, oil-gas. The problem is solved in the low frequencies approximation, when wavelength is more large than the thicknesse of alternating layers and the layer becames as anisotropic liquid.