Diamantina Fracture Zone western side of the Diamantina Fracture Zone at is another, larger pit, named Dordrecht Hole, with a north-south extent of 50 km. Its maximum depth is 7079 m at . "Dordrecht" was the name of a vessel of the Dutch East India Company, which explored the Australian west coast in 1619 and discovered the Houtman Abrolhos. The shallowest point in the area is the 1125-metre point in the Broken Ridge close to Ninety East Ridge. Diamantina Fracture Zone The Diamantina Fracture Zone is an area of the south-eastern Indian Ocean seafloor. It has a range of ridges and trenches. It
Ryukyu Trench km/s, 3.5 km/s, and 4.5–5 km/s. In the area of this transect, the wedge reaches a thickness of 9 km at 50 km from the trench. Beneath the wedge are several seismic layers within the oceanic crust. Separate ocean bottom seismography and multi-channel seismic studies provide insight into the structure of the northern end of the Ryukyu trench region. Features of note include a thick (7–12 km) low velocity (4–5 km/s) zone on the landward side of the trench, the existence of subducting paleo-arc crust near the top of the trench in contrast to simple oceanic crust located at the