Study on the effect of dual-freedom coupling between the tilt geophones and the surface

In the process of coalfield seismic data acquisition, there is a situation of repeated geophone layout at the same point. The tilt angle difference of the geophones will leads the change of coupling condition between the geophone and the surface, which affects the quality of seismic data acquisition. In this paper, the tilt angle parameters of geophone were introduced into the coupling system of the geophone and the surface. From the point of view of vibration mechanics, the "vibration system with coupling of the dual degree of freedom" of tilt geophone was deduced. The influences of the tilt angle of geophone, relative damping coefficient between the geophones and the surface, and the surface medium parameters on the coupling system were studied. The influence mechanism of repeated geophone layout at the same detection point on seismic data acquisition was analyzed. The results show that the increase of geophone dip will attenuate the amplitude-frequency response of the coupling system and increase the resonance frequency of the coupling system. The tilt of geophone will affect the coupling effect between the geophone and the surface, and reduce the quality of seismic data acquisition. The results show that the coupling model of the tilt geophones and the surface is reasonable, can be used to guide and standardize the seismic data acquisition.