How to choose geophone in seismic exploration?

1.  What is the difference between horizontal wave geophone and vertical wave geophone?

Horizontal wave geophone is sensitive to horizontal wave while the vertical wave geophone is sensitive to vertical wave. The horizontal wave geophone should be embedded horizontal and  preferably in one direction to avoid the different sensitivity in different position, the work is not easy.

2.  How to choose the frequency of geophone?
             Geophone Frequency/Hz
Vertical wave geophone  3D geophone 4.5 28 40 60 100
Seismic Imaging      
Velocity Test            
Surface Wave          
Shallow reflection