Patent ID: 8542556

Claim:
A vibration sensor array system having sub-array vibration sensing assemblies in uninterrupted contact with a solid medium for detecting horizontally polarized seismic shear wave or compressional wave dynamic motions in said solid medium and converting said detected dynamic motions to electrical signals corresponding to said dynamic motions, comprising: two or more said sub-array assemblies in contact with a two-dimensional area of the surface of said solid medium, each of said sub-array assemblies comprising: a rigid subassembly base plate; one or more vibration sensors mounted on said rigid subassembly base plate, said rigid subassembly base plate having mounted on an underside and in contact with said solid medium at least two rigid contact point elements communicating mechanical signals imparted by said dynamic motions in said solid medium to vibrations in said rigid subassembly base plate, said base plate vibrations detected and converted to electrical signals by said one or more vibration sensors, said rigid subassembly base plate having at least two compliant mounting columns attached to an upper side for mounting said rigid subassembly base plate to an underside of a hold-down plate distributing hold-down mass to each said at least two sub-array assemblies for uninterrupted contact with said solid medium; and a means for conditioning and combining said electrical output signals from said at least two sub-array assemblies to form a complete composite electrical output signal of said vibration sensor array system.