effects of topography on blast vibration attenuation

[sghvib]

Is there any research/publications that address ground borne vibration attenuation with changes in grade elevation? For example say there is construction blasting on a hill. The hole depth is < 10 ft. there is a ravine next to the hill that goes down 25 ft and then grade rises back up 15 ft. (the opposite side of the ravine is even with the bottom of the boreholes). the distance between the two location is 250-300 ft.

Does the typical scaled distance approach with the -1.6 attenuation coefficient produce a reasonable estimate of PPV at the other side of the ravive? Intuitively I want to say there should be essentially no vibration on the other side because of the discontinuity at grade. Is this correct? Is the phenomena documented somewhere?

thanks for any input.