Method for eliminating influence of invasion of air-layer drilling liquid on acoustic logging

According to physical geography knowledge, it is known that the speed of an air saturation ground layer is smaller than the speed of a water saturation ground water, a drilling liquid can permeate into a place around a shaft at a distance being 0.5-3 meters after an air layer is opened, rock around the shaft is changed to water saturation from air saturation, at the moment, an acoustic value measured by physical geography acoustic logging does not represent information containing an air ground layer, while the information of an original air layer is reflected and recorded by earthquake, amplitude phase difference is caused by water saturation ground layer acoustic logging to fabricate, synthesize, record and calibrate the air layer, and malposition of reflection time also can be caused. With the method for eliminating influence of invasion of air-layer drilling liquid on acoustic logging, the average speed of the air layer is calculated according to the reflection time difference between ground earthquake doc