The Jackup Glomar Adriatic I slips into the water at Marathon LeTourneau's Gulf Marine Division at Brownsville. The rig is a Marathon Class 116-C, cantilever self-elevating, offshore drilling platform. At launching, the platform's derrick and other drilling components, along with the remaining sections of its three legs, had yet to be installed. The Glomar Adriatic I, which is being constructed for Global Marine Drilling Company, will be capable of operating in water depths up to 300 feet.