作为地震反射法一个变种的陆地声纳法，是一种易掌握、仪器轻便的隧道掌子面前方地质预报的方法，它用锤击震源在隧道掌子面上设排列和测点工作，在预报岩溶、断层及破碎带、岩脉等方面成功地进行了20多个工区的预报，1995年通过了铁道科学院和铁道部鉴定。近年来这种由我国研究人员发明的方法特别在预报溶洞等方面显示了优于其它方法的特长，并已投产了第4代陆地声纳仪LDS-3。

The landsonar is presented in this paper, which is based on the principle of elastic reflection wave and is a method of geological forecasting in tunnel construction. Due to the light instrument and simple operation, the landsonar is widely used. The landsonar has been successfully used to forecast karst caves and faults in more than 20 cases. And the fourthgeneration landsonar LDS3 has been put into production.