The study and explanation of coalfield collapse columns, especially of small ones, constitute a key factor in coal mine safe production. However, it is very difficult to explain small coal collapses by seismic data of field reflection and refraction waves in practical production. In this paper, the characteristics of reflection and refraction wave sets and the influence of reflection wave set to refraction wave set are studied for coalfield collapse columns on the basis of ultrasonic simulation tests. The results show that coalfield high-resolution seismic data can reduce the radius of Fresnel zone to 1/5～1/3 for the target buried in the depth of 200～500 m, and interpret accurately collapse columns with diameters longer than 30m. Reliable explanation results can also be obtained for collapse columns with diameters of 15～30m. Therefore, the exploration precision is obviously improved.