Answer:
The feature found at the Wadati-Benioff zones are trenches.
The Wadati-Benioff zone is a sloping plane of seismicity defined by intermediate and deep earthquakes that occurs in subduction zones. It is named after the seismologists Kiyoo Wadati of Japan and Hugo Benioff of the United States, who independently discovered it.
The Wadati-Benioff zone is typically located on the overriding plate of a subduction zone and marks the boundary between the downgoing oceanic plate and the overlying continental or oceanic crust. The intense seismic activity at this zone is due to the friction and pressure created by the subduction process, leading to earthquakes that occur at varying depths.
Adjacent to the Wadati-Benioff zone lies the deep oceanic trench or simply undersea trench, which is typically parallel to continents or chains of islands. Trenches form where tectonic plates converge, with an oceanic plate typically subducting beneath a less dense continental or oceanic plate to create a steep-sided depression on the seafloor.