Fly-through from the south toward the north along the Mariana Arc (3 times vertically exaggerated). MR1 sidescan sonar data (grayscale) is overlaid on bathymetry data (color). The MR1 sidescan sonar data gives information about the character of the seafloor, rather than just its depth. Black represents areas of high reflectivity and white represents areas of low reflectivity. Data from the HAWAII MR1, owned and operated by the University of Hawaii, provided courtesy of Patty Fryer and Fernando Martinez (Univ of Hawaii), Bob Stern (U of Texas at Dallas), Sherm Bloomer (Oregon State University) and Bob Embley (NOAA Vents / NOAA Ocean Exploration Program).