A method for evaluating subsurface formations includes deploying at least two intersecting seismic transducer lines above an area of the subsurface to be surveyed. Each line includes spaced apart seismic transmitters on one side of the intersection and spaced apart seismic receivers on the other side. On each line, one of the transmitters is actuated and signals are detected at one of the receivers. The foregoing is repeated for each of the remaining receivers. The foregoing is then repeated for each of the remaining transmitters on each line. The detected signals are processed to enhance both specular and non-specular seismic events in the subsurface. The enhanced events may be stored and/or displayed.