Location of the Mariana Trench in the western Pacific OceanGEBCO 2019 bathymetry of the Challenger Deep and Sirena Deep. (a) Mariana Trench multibeam bathymetry data gridded at 75 m acquired on‐board the DSSV Pressure Drop overtop the GEBCO 2019 source grid (as shown in Figure 1) and the complete GEBCO 2019 grid with hillshade. EM 124 black contours at 500 m intervals, GEBCO 2019 grey contours at 1,000 m intervals. The white circle indicates the deepest point and submersible dive location, the white triangle indicates the submersible dive location from Sirena Deep, the red spot was the deepest point derived by van Haren et al., (2017). (b) Challenger Deep. (c) Sirena Deep. Bathymetric cross sections A’–A” and B’–B” over Challenger Deep and Sirena Deep displayed in (d) and (e), respectively.
The Sirena Deep, originally named the HMRG Deep, was discovered in 1997[1][2] by a team of scientists from Hawaii.[2] Its directly measured depth of 10,714 m (35,151 ft) is third only to the Challenger Deep and Horizon Deep, currently the deepest known directly measured places in the ocean.[3][4][5] It lies along the Mariana Trench, 200 kilometers to the east of the Challenger Deep and 145 km south of Guam.[1][2]
^Steve Nicholls (producer/writer), Victoria Coules (writer), Peter Brownlee (editor) (9 August 2009). Drain the Ocean (Documentary). National Geographic. Archived from the original on 13 July 2009.