Geological analysis suggest the current-day continents we know and love will drift together, forming a new supercontinent like ones that existed many millions of years ago. What’s not certain is where that supercontinent will be. The authors of a new Nature study suggest that the next supercontinent, dubbed Amasia, will join together up in the Arctic. Antarctica, though, would stay by its lonesome in the south.
What’s the News: In geologists’ traditional view of the middle of the Earth, the solid inner core is gradually growing as more of the liquid core freezes, as the planet continues its billions-of-years-long process of cooling off. But now scientists are suggesting that parts of the solid inner core get so hot that they turn liquid, and that this is all linked to what’s happening in the Earth’s crust—meaning that our the earthquakes, volcanoes, and plate tectonics that we see are connected to the very heart of the planet.
What’s the News: Geologists have known for years that tectonic plates affect climate patterns. Now they say that the opposite is also true, finding that intensifying climate events can move tectonic plates. Using models based on known monsoonal and plate movement patterns, geologists say that the Indian Plate has accelerated by about 20% over the past 10 million years. “The significance of this finding lies in recognising for the first time that long-term climate changes have the potential to act as a force and influence the motion of tectonic plates,” Australian National University researcher Giampiero Iaffaldano told COSMOS.
A huge bounty of amber unearthed in India is giving researchers a peak at the wildlife that inhabited the area 50 million years ago, via the insects that are trapped inside it. The findings, published in the Proceedings of the National Academy of Sciences, suggest that the Indian subcontinent was not as isolated as previously thought.
“We know India was isolated, but … the biological evidence in the amber deposit shows that there was some biotic connection,” says David Grimaldi, curator in the Division of Invertebrate Zoology at the [American Museum of Natural History]. [Press release]
About 150 million years ago, the Indian tectonic plat separated from the African plate and began its 100 million year journey to Asia. During that long journey the subcontinent was isolated from all other continents, giving its wildlife the chance to evolve in distinctly different ways (much like the evolution of marsupials in Australia). Since the amber was deposited in the form of sticky tree resin 50 million years ago, it gives researchers insight into the insects that were adrift on the subcontinent.
“The amber shows, similar to an old photo, what life looked like in India just before the collision with the Asian continent,” says Jes Rust, professor of Invertebrate Paleontology at the Universität Bonn in Germany. “The insects trapped in the fossil resin cast a new light on the history of the sub-continent.” [Press release]
Is there less of the moon to love than there used to be?
Yesterday came the news that our natural satellite might have shrunk 100 meters in diameter in relatively recent geologic time. The Lunar Reconnaissance Orbiter found a plethora of scarps across the lunar surface, far more than we knew about before. These cliff-like features can appear on Earth from tectonic shifts, but there’s no continental drift on the moon. Thus, the most likely explanation is: The moon shrunk. If it did, the surface would buckle under the pressure and create these scarps. Astronomers say that the gradual cooling of the moon’s interior probably caused the shrinkage.
Don’t worry about the tides disappearing, though. “Recent” means a different thing to geologists than to everyone else, and in this case it has taken a billion years for the moon to shrink in diameter just 0.003 percent.
For plenty more on the find, check out Phil Plait’s post at Bad Astronomy.
Bad Astronomy: The Moon Is Shrinking!
80beats: Study: There’s Water on the Lunar Surface, but Inside It’s Bone Dry
80beats: Found on the Moon: A Soviet Laser Reflector That Was Lost for 40 Years