A mechanism that counters established thinking on how the rate at which tectonic plates separate along midocean ridges
controls processes such as heat transfer in geologic materials, energy circulation, and even biological production has been revealed by a Georgia Institute of Technology, Atlanta, study.
That little-explored midocean ridge
, which is spreading slower than other known seams, runs within 350 km of the North Pole and lies at frigid depths between 4,500 and 5,000 meters.
Although Axial forms part of the global midocean ridge
, most other ridge segments do not form broad, high volcanoes, says Rachel M.
Later, lava erupting from the midocean ridge
pours over some of the fractures, coating portions of the hills with fresh volcanic rock.
At continent-building plate margins, the fronts of plates created at different midocean ridges
exert pressure on one another in opposite directions.
The most-celebrated deep-ocean habitats--seen for the first time about 100 miles off the Galapagos Islands in 1977--are the hydrothermal vents now known to occur along deep, midocean ridges
throughout the world.
Specifically, they reveal a link between seamounts and earthquakes, as seamounts are formerly active volcanoes and therefore generally are located near tectonically active plate boundaries, midocean ridges
, and subducting zones.
are classified into two groups: fast- and slow-spreading.
Hot upwelling of volanic rock from the mantle typically occurs in two environments: midocean ridges
, which are linear chains of volcanic activity along the boundary where two plates move away from one another; and "hotspots," which are point sources of high volcanic output associated with quasistationary and long-lived heat sources in the mantle.
Then, the deep-reaching waves were guided by midocean ridges
, Titov and his colleagues report in an upcoming Science.
Most thin areas are created at midocean ridges
and therefore lie beneath oceans, the researchers say.
The frigid temperatures at the site stand in marked contrast to the hellish conditions of the ecosystems thriving near the hydrothermal vents typically associated with midocean ridges