

In the remote southern Indian Ocean, straddling the Antarctic Polar Front, lies a mostly submarine plateau one-third the size of the contiguous United States. The Kerguelen Plateau is one example of a unique type of Earth feature, a large igneous province (LIP). One of the least understood features in the ocean basins, LIPs are believed to be the surface manifestations of massive pulses of volcanism that originated deep within Earth’s mantle in association with narrow upwelling systems, known as mantle plumes or hotspots. Despite the challenging winds and seas of the Kerguelen "Triangle," where two Vendée Globe round-the-world racing yachts capsized in 1997, the Ocean Drilling Program (ODP) mounted an expedition (ODP LEG 183-December 1998 to February 1999) to study the Kerguelen Plateau and its now separate, conjugate feature, Broken Ridge. Mike Coffin of The University of Texas Institute for Geophysics (UTIG) and Fred Frey of the Massachusetts Institute of Technology led the team of 28 scientists representing eight countries to study the plateau’s eruption history by analyzing samples of sediment and lava collected from deep beneath the sea-floor. Since its formation the plateau has subsided to great water depths (1 to 2.5 km). Surprising evidence recovered on Leg 183 revealed that the Kerguelen Plateau had existed as large landmasses above sea level at three different times during an 80 million year period, before finally becoming submerged about 30 million years ago. Concept Strand
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