Abstract:Theoretic analysis showed that the dominant frequency of seismic wavelet in desert decreases in inverse proportion to square of spreading distance,its coefficients are related to the velocity of desert medium and the nature of source,this non-linearization leads to significant low-frequency of seismic wavelet in desert. The paper gave the formina of apparent dominant frequency of seismic wavelet in desert and pointed out that the funda-mental method for increasing the dominant fre-quency of targets does not lie on unlimitedly in-creasing charge size and using dynamite with low explosive speed and lie on increasing the explosive depth of source(increasing ho)and expanding wave front of shock wave after source explosion(in-creasing ro).