There may be a second massive ocean deep beneath the surface

Chemically bonded to minerals in the transition zone, Earth’s mantle may be rather wet…

Deep within the Earth, staggering pressures mix with high temperatures to compact regular materials into exotic minerals. Under these extreme conditions, one familiar mineral—a blend of magnesium, iron and sand that geologists call olivine (and most people would know by its gemstone form, peridot)—is transformed into a material called ringwoodite. This material is produced in Earth’s so-called “transition zone,” from around 255 to 416 miles depth, where the outer mantle turns to the inner mantle. While ringwoodite has been found before, in meteorites crashed to Earth, ringwoodite of terrestrial origin is a…

New swarm of earthquakes started at El Hierro, Canary Islands

A new swarm of earthquakes started yesterday at El Hierro, Canary Islands. So far, almost 200 tiny quakes (none above magnitude 3 so far) have occurred in a broad N-S oriented area beneath the NE part of the island at around 18 km depth.

A possible explanation includes a new magmatic intrusion at depth (magma accumulating at the lower crust-mantle boundary), Volcano Discovery reports.

Earthquakes at El Hierro recorded in last 3 days. Image credit: IGN

Shaking, cracks and dangerous rockfalls from strong M 5.4 quake near El Hierro, Canary Islands (December 28, 2013)

“The triangular island of Hierro is the SW-most and least studied of the Canary Islands. The massive Hierro shield volcano is truncated by a large NW-facing escarpment formed as a…