The CTD (Conductivity-Temperature-Depth sensor) is deployed into the ocean. All of the Niskin bottles are held open before deployment and are closed individually to collect water samples at different depths as the CTD carousel rises through the water column. Photo credit: John Wonderly, Clallam Bay School, V14.
The Conductivity, Temperature and Depth (CTD) probe lies within a large carousel of Niskin water bottles. The carousel is lowered to the seafloor while the CTD makes measurements. On the 'ride' up, a person on deck triggers the water bottles to close (one at a time) to collect a water sample at different depths. Photo credit: Mitch Elend, University of Washinton, V14.
Samples of fresh basalt were collected from Axial Seamount's caldera floor. When fresh, the outer surface of the rock is glassy due to the very rapid cooling and crystallization that occurs when the hot lava comes in contact with the 2oC seawater. This glass – known as obsidian – is very sharp and crumbles easily. (Photos by Leslie Sautter)