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.
by F. Maccaferri et al., October 23, 2017 in NatureCommunication
The results reveal that a lateral collapse can trigger a significant deflection of deep magma pathways in the crust, favouring the formation of a new eruptive centre within the collapse embayment. Our results have implications for the long-term evolution of intraplate volcanic ocean islands.
by Michael R. Rampino et al., October 2017, in Nature
Anomalous peaks of nickel abundance have been reported in Permian-Triassic boundary sections in China, Israel, Eastern Europe, Spitzbergen, and the Austrian Carnic Alps. New solution ICP-MS results of enhanced nickel from P-T boundary sections in Hungary, Japan, and Spiti, India suggest that the nickel anomalies at the end of the Permian were a worldwide phenomenon.
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by McMaster University, October 2, 2017 in ScinceDaily
Life on Earth began somewhere between 3.7 and 4.5 billion years ago, after meteorites splashed down and leached essential elements into warm little ponds, say scientists. Their calculations suggest that wet and dry cycles bonded basic molecular building blocks in the ponds’ nutrient-rich broth into self-replicating RNA molecules that constituted the first genetic code for life on the planet.
by National Science Foundation, September 26, 2017 in ScienceDaily
Expedition co-chief scientist Rupert Sutherland of Victoria University of Wellington in New Zealand said researchers had believed that Zealandia was submerged when it separated from Australia and Antarctica about 80 million years ago.
Big geographic changes across northern Zealandia, which is about the same size as India, have implications for understanding questions such as how plants and animals dispersed and evolved in the South Pacific.