Abstract：This paper mainly discusses velocity dispersion due to high frequency in ultrasonic core measurement of laboratory.We adopt Gassmann's equation to calculate VP and VS of the brine-saturation core sample,then contrasted them to actual measured ultrasonic velocities of the samples.Therefore the magnitude of velocity dispersion is estimated.Through research of a few examples in 2 areas in South China Sea,we have found the following discoveries: When the properties of reservoir samples are good,the velocity dispersion is small,lab rock physics research results are suggested to be applied in seismic exploration.When the properties of reservoir samples are poor,the velocity dispersion is strong,we should be careful in applying lab core data in seismic exploration.
