Plate tectonics determines how the surface of the Earth is shaped over geological time; however, we do not know how this process started. New research by a group of geoscientists demonstrates that diamonds can be used to reveal how a buoyant section of mantle beneath some of the continents became thick enough to provide long term stability.
Continue reading “Mantle keels”Deep mantle fluid
The water content of Earth’s mantle is a key measurement of Earth’s water budget. Global recycling of water on Earth drives important forms of volcanism such as island arcs, controls the flow of upper-mantle fluid and plays a role in the evolution of mantle plumes.
Continue reading “Deep mantle fluid”Deep-earth recycling
Diamonds that formed deep in the Earth’s mantle contain clues of chemical reactions that occurred on the seafloor and can help geoscientists understand how material is exchanged between the planet’s surface and its depths.
Continue reading “Deep-earth recycling”Deep-focus earthquakes
The cause of Earth’s deepest earthquakes has remained a mystery until now. New research by a team of Carnegie scientists provides evidence that fluids play a key role in deep-focus earthquakes which occur between 300 and 700 kilometers below the planet’s surface.
Continue reading “Deep-focus earthquakes”Mass ocean extinction
Our planet’s worst mass extinction took place 252 million years ago when massive volcanic eruptions caused epic climate change. Most animal species went extinct and set the stage for the early days of the age of Dinosaurs.
Continue reading “Mass ocean extinction”Hydrogen in Earth’s core
High-temperature and high-pressure experiments to simulate the core of the young Earth demonstrate for the first time that hydrogen can bond strongly with iron in extreme conditions. This explains the significant presence of hydrogen in the Earth’s core that arrived as water from bombardments billions of years ago.
Continue reading “Hydrogen in Earth’s core”Plate tectonic onset
Scientists led by Michael Ackerson at the Smithsonian’s National Museum of Natural History found new evidence that plate tectonics started roughly 3.6 billion years ago. Plate tectonics is essential to the Earth’s ability to support life.
Continue reading “Plate tectonic onset”Microcontinent deformation
Geoscientists at the University of Toronto and Istanbul Technical University have made a new discovery in plate tectonics which shows that a large amount of damage occurs to areas of Earth’s crust long before it should be geologically altered by known plate-boundary processes.
Continue reading “Microcontinent deformation”Rio Grande rift study
Rocks from the Rio Grande continental rift have revealed new evidence for how continents remain stable over billions of years. A Continental rift is the belt or zone of the continental lithosphere where the extensional deformation (rifting) is occurring. These zones have important consequences and geological features, and can lead to the formation of new ocean basins.
Continue reading “Rio Grande rift study”Cratons fused below
Billions of years of plate tectonics have destroyed much of what was the earliest continents. The parts of the continents that remain have survived because their composition makes them buoyant and strong. These blocks known as cratons were thought to be indefinitely stable are now thought to not only break up but can also be fused back together again.
Continue reading “Cratons fused below”