Huge 'Ocean' Discovered Inside Earth

Scientists scanning the deep interior of Earth have found evidence of a vast water reservoir beneath eastern Asia that is at least the volume of the Arctic Ocean.


The discovery marks the first time such a large body of water has found in the planet's deep mantle. 


The finding, made by Michael Wysession, a seismologist at Washington University in St. Louis, and his former graduate student Jesse Lawrence, now at the University of California, San Diego, will be detailed in a forthcoming monograph to be published by the American Geophysical Union.


Looking down deep

The pair analyzed more than 600,000 seismograms — records of waves generated by earthquakes traveling through the Earth—collected from instruments scattered around the planet. 

They noticed a region beneath Asia where seismic waves appeared to dampen, or "attenuate," and also slow down slightly. "Water slows the speed of waves a little," Wysession explained. "Lots of damping and a little slowing match the predictions for water very well."

Read on:  http://www.livescience.com/1312-huge-ocean-discovered-earth.html

Life discovered in deepest layer of Earth’s crust

Just when you thought we had discovered signs of life everywhere possible on Earth, a new expedition has revealed a complete ecosystem existing in the deepest layer of the planet’s crust.


A drilling expedition towards the Earth’s centre would mean digging through sediment, a layer of basalt, and then hit the gabbroic layer, which lies directly above the mantle.

A team led by Stephen Giovannoni of Oregon State University in Corvallis drilled down to 1391 metres, where temperatures reach 102 degrees Celsius. Here, they found communities of bacteria that were sparse but widespread, reports New Scientist.

But the type of organisms they came across was very different.

One key difference was that archaea were absent in the gabbroic layer. Also, genetic analysis revealed that unlike their upstairs neighbours, many of the gabbroic bugs had evolved to feed off hydrocarbons like methane and benzene.

This could mean that the bacteria migrated down from shallower regions rather than evolving inside the crust.

"This deep biosphere is a very important discovery," said Rolf Pedersen of the University of Bergen, Norway.

He added that the reactions that produce oil and gas abiotically inside the crust could occur in the mantle, meaning life may be thriving deeper yet.

The find is published in PLoS ONE.