This image shows a contoured plan-view map of processed gravity data, specifically the residual Bouguer anomaly, with deeper bedrock indicated in the upper middle right of the image in blue hues and shallower bedrock shown to the middle and upper left image, and additionally to the lower right in red and brown tones. Green shades bisect the plot from the lower-left corner to the upper right corner. Image by Dr. Nigel Crook

Residual Bouguer Anomaly contoured map of processed gravity data overlain on a raised-relief map of the survey area. Blue shades, for example in the top right, are interpreted as deeper bedrock zones where alluvium thickness is greatest, and red and brown shades indicate shallower bedrock zones. The green shades are areas of more moderate alluvial depths.