Abstract: A vibrating hole forming device for seismic exploration in which a vertically elongated mounting pipe with attached rack gear is powered vertically by a hydraulically driven pinion gear which will mechanically push the pipe downwardly into the earth's surface. A vibrating mechanism imparts vibration to the downward force exerted by the pinion gear and rack gear. Vibration is imparted to the pipe automatically when hydraulic pressure required to operate the pinion gear reaches a predetermined pressure such as when the point on the lower end of the pipe encounters a predetermined resistance to further downward movement. This enables a lightweight unit to impart a constant downward force and a vibration force when needed to enable the device to penetrate through sands or extremely dense subsurface terrain thereby eliminating the necessity of providing a heavy weight vehicle such as is required when conventional hole forming devices are used on which the device is mounted.