Recycling of oceanic crust

In plate tectonics, there are three categories of volcanism: ocean ridge, arc and intraplate. While the origins of ocean ridge and arc volcanism are readily explained by plate tectonics, intraplate volcanism (IPV) is not. The dominant hypothesis for the origins of IPV is by mantle plumes from deep within the interior of the earth.

Early magma ocean

New research by the University of Cambridge has found evidence in ancient rocks from Greenland that the Earth was at a time almost entirely molten. The study yields information on an important period in our planet’s formation when a deap sea of magma stretched across Earth’s surface and extended hundreds of kilometers into the interior.

Mountainless Earth

According to a study published in the journal Science, for nearly a billion years during our planet’s “middle age” (1.8 billion to 0.8 billion years ago), Earth’s mountains stopped growing while erosion wore down existing peaks to stumps. This extreme mountain-forming hiatus resulted from a persistent thinning of Earth’s continental crust. 

Ice free Greenland

Scientists have discovered that the Greenland ice sheet has melted to the ground at least once in the last million years despite CO2 levels far lower than today. This ice sheet holds enough frozen water to swamp coastal cities worldwide.

River of rocks

Geologists have previously thought that tectonic plates move because they are pulled by the weight of their sinking regions and that an underlying, hot, softer layer called the asthenosphere acts as a passive lubricant. Now a team of geologists at the University of Houston has found that layer is flowing swiftly, moving fast enough to …

Laschamp excursion record in tree rings

A team led by Alan Cooper found a detailed record of the Laschamp excursion about 41,000 years ago from the rings of New Zealand swamp kauri trees. The record reveals a substantial increase in the carbon-14 content of the atmosphere during the period of weakening magnetic field strength preceding the polarity switch.