The mystery of how an Antarctic underwater volcano chain formed may have finally been solved.
The Marie Byrd Seamounts are a group of eight large volcanoes and many small cones spanning the seafloor offshore of West Antarctica.
To geologists, volcanoes lined up like Russian nesting dolls in the middle of a tectonic plate usually signal a mantle plume, a hot upwelling coming from the bowels of the Earth. As the planet's tectonic plates slowly trundle over the hot spot, magma punches through the crust, creating volcanoes. A classic example of this phenomenon is seen in the Hawaii and Emperor Seamount chain.
But the first comprehensive survey to peel back the secrets of the Marie Byrd Seamounts failed to find any signs of a hotspot — even though the volcanoes contain geochemical tracers that point to a hotspot origin.
Yet researchers at the GEOMAR Helmholtz Centre for Ocean Research Kiel in Germany think they've solved the riddle of what formed the seamounts.
The submerged volcanoes formed when part of the Earth's crust pulled apart some 60 million years ago, ...more