Abstract: A spring for a geophone has a plurality of spring arms connecting inner and outer concentric annular portions to resiliently resist relative movement of the annular portions along the concentric axis. Two support arms are connected to each spring arm. Each support arm has one end connected to one of the annular portions and the other end connected to the spring arm at a point spaced from the point of connection of the other spring arm to increase the natural frequency of the spring in a direction lateral to the concentric axis without changing appreciably the natural frequency of the spring along the concentric axis.