Why do ocean ridges form




















Image courtesy of Haymon et al. The mid-ocean ridge is a continuous range of undersea volcanic mountains that encircles the globe almost entirely underwater. It is a central feature of seafloor terrain that is more varied and more spectacular than almost anything found on dry land, and includes a collection of volcanic ridges, rifts, fault zones, and other geologic features. At nearly 60, kilometers 37, miles long, the mid-ocean is the longest mountain range on Earth. The vast majority of volcanic activity on the planet occurs along the mid-ocean ridge, and it is the place where the crust of the Earth is born.

The material that erupts at spreading centers along the mid-ocean ridge is primarily basalt, the most common rock on Earth. Because this spreading occurs on a sphere, the rate separation along the mid-ocean ridge varies around the globe. In places where spreading is fastest more than 80 millimeters, or 3 inches, per year , the ridge has relatively gentle topography and is roughly dome-shaped in cross-section as a result of the many layers of lava that build up over time.

At slow- and ultra-slow spreading centers, the ridge is much more rugged, and spreading is dominated more by tectonic processes rather than volcanism. Scientists study the physics, chemistry, and biology of mid-ocean ridges gain insight into how Earth works in very fundamental and often surprising ways. At hydrothermal vents there are body-snatchers, intestinal hitchhikers, and chest-bursters, but something about them is still alluring to Lauren Dykman.

In , WHOI scientists made a discovery that revolutionized our understanding of how and where life could exist on Earth and other planetary bodies. An ultrasound for the Earth? January 6 to 27, Join researchers as they study the biology, geology, and chemistry of some of the deepest hydrothermal vents on Earth.

October 7 to November 6, Follow researchers as they explore one of the deepest points in the Caribbean Sea, searching for life in extreme seafloor environments. He uses techniques that span isotope geochemistry, next generation DNA sequencing, and satellite tagging to study the ecology of a wide variety of ocean species. Due to the fast spreading rates, there is no rift valley in the Pacific, just a smooth volcanic summit with a crack along the crest that is much smaller than the Atlantic rift valley.

Despite being such prominent feature on our planet, much of the mid-ocean ridge system remains a mystery. While we have mapped about half of the global mid-ocean ridge in high resolution, less than one percent of the mid-ocean ridge has been explored in detail using submersibles or remotely operated vehicles. New York: Wiley-Interscience, p. Mitchell, A. Geology 79, — Morgan, W. Petroleum Geologists Bull.

Normark, W. Pipkin, B. Freeman and Co. Pitman, W. Sclater, J. Talwani, M. Research, 84, — Vine, F. Phinney, ed. Princeton, N. Wilson, J. Related Stories. However, many In a new study, researchers have uncovered the mechanism for this seeming paradox, and it comes And researchers Coal Creation Mechanism Uncovered Nov.

Rarely do we consider what happens after we flush that toilet or turn off that tap.



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