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This article focuses on seabed canyons with riverlike characteristics. The newly discovered canyon system-which the researchers named Cap Timiris Canyon, after a nearby cape on the African coast-looks like a river valley, only it's on the bottom of the sea. Finding the canyon was a surprise because a submarine feature of that size had never previously been reported off the coast of a desert area. Researchers are studying undersea canyons with a variety of tools. Scientific instruments deployed off southern California have recorded the frequency and the violence of turbidity currents and provide hints as to what triggers them. Long-buried canyons can point the way to old deposits of carbon-rich material that may have been transformed into crude oil. Also, because the materials that now fill the old canyons often are more porous than the surrounding, intact rock, they're excellent collectors of any petroleum that has seeped into them from nearby sediments.

Reports the results of a study which examined the causes the tsunami which struck Papua New Guinea on July 17, 1998. Examination of the sea-floor by scientists; Their conclusion that the tsunami was caused by a slump or slide in the seabed; Evidence for such a slide; Publication of the study in the July 27, 1999 `EOS.'

This article discusses the South Pacific Bare Zone, a large area of seafloor which is nearly devoid of sediments. The sediment-poor region is about the size of the Mediterranean Sea says David K. Rea, a marine geologist at the University of Michigan in Ann Arbor. An unusual combination of circumstances has left the region without the mineral and organic sediments that are typical elsewhere in the world's oceans, Rea and his colleagues report in the October 2006 issue of "Geology."

Discusses ocean research expeditions to study ocean floor life. How microbes have been found; Discussion of similar life possibly living in the ocean floors of other planets and moons; Discussion of the subseafloor waters and their characteristics.

The article details an international expedition which rescued a 12-year effort to bore beneath the sea floor and open a window into the Earth's internal workings in 1991. It ranks as one of the most expensive fishing trips of all time, but this international expedition did not hook any deep-sea delicacies. Instead, crew members hauled up broken pieces of drilling equipment. The machinery had been clogging the deepest hole ever cut in the ocean floor and had threatened to end all drilling at this hole, known as 504B and located near the Galapagos Islands. "This is a landmark," says marine geologist Henry Dick of the Woods Hole Oceanographic Institution in Massachusetts, who served as co-chief scientist on the cruise. Ocean crust covers roughly two-thirds of Earth's surface. With scores of other potential drill sites around the world, scientists debated whether to risk spending more time on this valuable but problematic hole. In the past, scientists have used ophiolites--slivers of ancient seafloor that have been pushed up onto the continents--as an accessible analog for studying ocean crust formation. But in the November 14, 1991 "Nature," Don Elthon of the University of Houston suggests that ophiolites differ from most ocean crust.

Describes an actual eruption identified by researchers that may be part of a seafloor spreading episode, the volcanic process that creates the deep ocean floor. Comparisons of two maps from the same area produced at different times; Role of pillow lavas; Implications of findings.

Examines the patterns of magnetic stripes in the ocean floor. Direct measurement of the magnetic properties of rocks lying below the seafloor; Compositions of basalts; Comparison between the magnetization of the dike layer and extrusive layer.