Chirp Sonar

During this cruise, a chirp sub-bottom profiler aboard the AUV Sentry will aid in seafloor surveys of methane seeps at summit of Southern Hydrate Ridge. Gas hydrate forms in specific conditions of low temperatures, high pressure and adequate gas concentrations within the sediments. The zone that solid gas hydrates form in is known as the gas hydrate stability zone. The boundary between the sediment with solid gas hydrate within this zone and sediment with free gas results in a distinctive acoustic reflection known as the bottom-simulating reflector that can be identified in data collected with the chirp system. We will use the chirp sub-bottom profiler during surveys of Southern Hydrate Ridge to help classify the distribution of gas hydrate within the study area.