Fig. 1From: Surface wave attenuation in the shallow subsurface from multichannel–multishot seismic data: a new approach for detecting fractures and lithological discontinuitiesSchematic diagram of method to extract amplitude ratio A c in Eq. 3. a CMP with minimum receiver spacing dr 1 and b CMP with larger receiver spacing dr 2. c Definitions of positive- and negative-offset data. Triangles represent receiver positions. In generating amplitude ratio data, the data with the longer offset (red) are divided by the data with shorter offset (blue)Back to article page