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
Mariana Trench a survey which mapped the entire trench to resolution. The mapping revealed the existence of four rocky outcrops thought to be former seamounts. The Mariana Trench is a site chosen by researchers at Washington University and the Woods Hole Oceanographic Institution in 2012 for a seismic survey to investigate the subsurface water cycle. Using both ocean-bottom seismometers and hydrophones the scientists are able to map structures as deep as beneath the surface. Four descents have been achieved. The first was the manned descent by Swiss-designed, Italian-built, United States Navy-owned bathyscaphe "Trieste" which reached the bottom at 1:06 pm on 23