The image is not really of a wadi, but it is reminiscent of one.
Wadi is the Arabic term for a dry riverbed that runs with water only during heavy rains – also called an arroyo, wash, or draw. Canyons also display water-cut features and are typically located in arid environments. However, canyons can also be submarine features offshore from the mouths of rivers. Turbidites are layers of sediment deposited underwater by rivers dumping their suspended load offshore. (Video of imaging of offshore canyon in Nova Scotia : 33.6 - 56K Dial-Up : Cable/DSL : High-Speed / T1)