Cataclysmic Volcanic Eruption Predicted in 200 Million Years

Earth could be partially destroyed in a cataclysmic volcanic eruption--in 200 million years. A seismologist has recently analyzed seismic waves that bombarded our planet's core and received a glimpse of the earliest roots of this type of explosion.

The new study, set for publication in the journal Earth and Planetary Science Letters, used the highest-resolution method to date in order to make seismic images of the core-mantel boundary of Earth. The scientists used 4,221 seismograms from hundreds of seismometers around the world that detected 51 deep earthquakes originating more than 60 miles beneath the surface. Using this data, Michael Thorne, one of the authors of the study, and his colleagues then looked for secondary earthquake shear waves. After performing 200 days-worth of supercomputer simulations where hundreds of possible shapes and continent-sized piles were examined, the researchers found the best shapes that could explain the seismic wave patterns.

Since the early 1990s, scientists have known of the existence of two massive "thermochemical piles" sitting above Earth's core and beneath most of the planet's volcanic hotspots. With these new images, though, the scientists conducting this study found that the pile under the Pacific is actually the result of an ongoing collision between two or more piles. At the merging point, the scientists saw a spongy blob of partly molten rock the size of Florida. This massive blob is located beneath the volcanically active Samoan hotspot.

So what does this mean exactly? The study's computer simulations showed that when these piles merge together, there may be the possibility of triggering a massive plume explosion. This eruption would be similar to hotspot plume supervolcano eruptions like those during the past two million years at Wyoming's Yellowstone caldera. The resulting effects covered North America with volcanic ash.

The new findings show a rare glimpse of the Earth 1,800 miles beneath its surface. The boundary between the planet's molten outer core and its warm mantel rock has often been compared with a conveyer belt. As the tectonic plates of Earth's crust and uppermost mantel shift, they drift across the warmer, convecting lower mantle.

Although Thorne and his colleagues have detected this blob, the eruption shouldn't be set off any time soon--if ever. The prediction for it occuring is so far in the future, that more than likely some other cataclysmic event will have happened by then.