by Bristol University, February 19, 2019 in ScienceDaily
A new study on the timescale of plant evolution has concluded that the first plants to colonize the Earth originated around 500 million years ago — 100 million years earlier than previously thought.
For the first four billion years of Earth’s history, our planet’s continents would have been devoid of all life except microbes.
by Georgia Institute of Technology, February 17, 2018 in ScienceDaily
In popular culture, asteroids play the role of apocalyptic threat, get blamed for wiping out the dinosaurs — and offer an extraterrestrial source for mineral mining. But for one researcher, asteroids play an entirely different role: that of time capsules showing what molecules originally existed in our solar system. Having that information gives scientists the starting point they need to reconstruct the complex pathway that got life started on Earth.
by Helmholtz Centre for Ocean Research Kiel (GEOMAR), February 13, 2018 in ScienceDaily
When the seabed loses its stability and starts to move, it often happens in much larger dimensions than landslides ashore — and at slopes with very low gradients. At the same time, discplacement of large amounts of sediment under water scan cause devastating tsunamis. However, why and when submarine landslides develop is hardly understood. Marine scientists have now published possible causes based on observations on submarine landslides off the coast of northwest Africa.
by T. Girona, C. Huber, C. Caudron, January 24, 2018 in Nature
A long-standing question in Earth Science is the extent to which seismic and volcanic activity can be regulated by tidal stresses, a repeatable and predictable external excitation induced by the Moon-Sun gravitational force. Fortnightly tides, a ~14-day amplitude modulation of the daily tidal stresses that is associated to lunar cycles, have been suggested to affect volcano dynamics. However, previous studies found contradictory results and remain mostly inconclusive. Here we study how fortnightly tides have affected Ruapehu volcano (New Zealand) from 2004 to 2016 by analysing the rolling correlation between lunar cycles and seismic amplitude recorded close to the crater. (…)
by University of Chicago, January 9, 2018 in ScienceDaily
Though mass extinctions wiped out staggeringly high numbers of species, they barely touched the overall ‘functional’ diversity — how each species makes a living, be it filtering phytoplankton or eating small crustaceans, burrowing or clamping onto rocks.
by Heidelberg University, November 24, 2017 in ScienceDaily
In recent years, researchers have identified a small group of stalactites that appear to have calcified underwater instead of in a dry cave. The Hells Bells in the El Zapote cave near Puerto Morelos on the Yucatán Peninsula are just such formations. Scientists have recently investigated how these bell-shaped, meter-long formations developed, assisted by bacteria and algae.
by Helmholtz Centre for Ocean Research Kiel (GEOMAR), November 21, 2017 in ScienceDaily
How deep can seawater penetrate through cracks and fissures into the seafloor? By applying a new analysis method, an international team of researchers has now discovered that the water can penetrate to depths of more than 10 kilometers below the seafloor. This result suggests a stronger cooling effect on the hot mantle.
Credit : GEOMAR
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by University of Texas at Austin, November 21, 2017 in ScienceDaily
Earth’s Moon had a rough start in life. Formed from a chunk of Earth that was lopped off during a planetary collision, it spent its early years covered by a roiling global ocean of molten magma before cooling and forming the serene surface we know today.
by National Geography, 2017
The British Isles were once neither British nor isles
Things aren’t always what they seem on the surface. Looking at the area between mainland Europe and the eastern coast of Great Britain, you probably wouldn’t guess it had been anything other than a great expanse of ocean water. But roughly 12,000 years ago, as the last major ice age was reaching its end, the area was very different. Instead of the North Sea, the area was a series of gently sloping hills, marshland, heavily wooded valleys, and swampy lagoons: Doggerland.
by Geological Society of America, October 26, 2017 in ScienceDaily
A new geological record of the Yellowstone supervolcano’s last catastrophic eruption is rewriting the story of what happened 630,000 years ago and how it affected Earth’s climate. This eruption formed the vast Yellowstone caldera observed today, the second largest on Earth.