Drill ship (1f/3m).
L/B/D:
399.9 × 65.3 × 20 (121.9m × 19.9m × 6.1m). Tons:
6,281 grt. Hull:
steel. Comp.:
70. Mach.:
diesel-electric, 5,100 bhp, 2 screws; 11 kts. Built:
Levingston Shipbuilding Co., Orange, Tex.; 1968.
Named in honor of the oceanographic survey vessel
HMS Challenger (Glomar was an acronym for her owner, Global Marine, Inc.), the distinctive-looking Glomar Challenger resembled a floating oil rig, with a 45-meter-high lattice drill derrick situated amidships. The idea for Glomar Challenger arose out of the need for a way to extract core samples from the ocean floor to study the climatological and geological evolution of Earth. In the words of Cesare Emiliani, a hole bored on the seabed was necessary because
geographical, geochemical, micropaleontological, and mineralogical analysis of the cores will yield information of great importance on the conditions prevailing on the ocean floor in the water column above, at the ocean surface, in the atmosphere, in neighboring continents, and even in outer space and in the sun, during the time of sediment deposition, that is during the past 100 × 106[100 million] years or so.
Emiliani's idea was adopted by the Joint Oceanographic Institutions for Deep Earth Sampling (JOIDES), which comprised the Lamont Geological Observatory, Scripps Institution of Oceanography, Woods Hole Oceanographic Institute, and the University of Miami, which used Glomar Challenger first in the Deep Sea Drilling Project, or DSDP.
The technology used in her work was that of the deep-sea drill. Rather than anchoring—an impossibility over the great depths in which she operated—Glomar Challenger was kept in position by a "dynamic positioning system" using sonar beacons on the ocean floor that relayed data to hydrophones aboard ship, which in turn activated bow and stern thrusters. Her complement comprised three groups: 24 scientists and technicians, a 12-man drilling team, and the ship's crew. The roughnecks operated the drill, which could bore a 1,000-meter hole in the surface of a 4,000-meter seabed. The drill string consisted of lengths of drill pipe of between 9.5 and 28.5 meters in length, with a tungsten carbide tip at the working end. The only major accident occurred when about 4,000 meters of drill pipe were lost while operating in 20-foot seas and 50-knot winds about 150 kilometers south of Cape Horn, in April 1974. To compound the crew's problems, three days later the ship was seized by an Argentine gunboat whose captain suspected Glomar Challenger of being an illegal oil-prospecting ship.
Glomar Challenger's contributions to scientific understanding were of enormous significance. From core samples retrieved on her earliest voyages—which JOIDES called "legs"—geologists were able to establish that Alfred Wegener's theory of continental drift, first advanced in about 1915 and subsequently debunked by U.S. geologists, was in fact correct. Researchers were also able to prove the theory of seafloor spreading and determine the age of the seafloor, which was put at about 38 million years. Later voyages also demonstrated that Earth's magnetic poles have reversed themselves repeatedly over time. During fifteen years of operation, Glomar Challenger operated in all the major seas of the world from the Arctic Ocean to the Ross Sea and the Mediterranean and Black Seas. After her ninety-sixth leg, in the Gulf of Mexico, Glomar Challenger was scrapped at Mobile in 1983.
Hsu, Challenger at Sea.
