Seismic Downhole Test is to obtain geotechnical elastic constants for analyses of soil behavior under both static and dynamic loads. The method is to install geophone on the borehole, then making artificial trigger on the surface. The impulse or artificial trigger can be rise compression wave and shear wave. The result of preliminary wave and the secondary wave can be used to get the dynamic characteristic of the soil or rocks.

The result of the applied seismic given to engineer for designing the resistance of earthquake on engineering structure. The seismic downhole test outlined here is based on ASTM D7400-08.