10 geological discoveries that absolutely changed 2020
This year, scientists have uncovered some of Earth’s best-kept secrets. They found hidden rivers, pieces of lost continents and remnants of ancient rainforests, and they delved into the ancient history of the planet using cutting-edge technology. Who knows what they will find next! Until we find out, here are 10 of the geological discoveries that rocked our world in 2020.
Historic supereruption in Yellowstone
The Yellowstone hotspot hides beneath the geysers and hot springs of the national park, and about 9 million years ago, the volcano exploded in two historic supereruptions, scientists have discovered. After analyzing ancient expanses of volcanic rock and volcanic deposits in the area, the team uncovered evidence of two previously unknown eruptions, which they named the McMullen Creek supereruption and the Grey’s Landing supereruption. The Grey’s Landing eruption broke records as the largest eruption in the Yellowstone hotspot ever detected; About 8.72 million years ago, the eruption covered approximately 8,900 square miles (23,000 square kilometers) of what is now southern Idaho and northern Nevada with volcanic debris.
The monstrous spots near the Earth’s core are bigger than we thought
Continent-sized boulders of rock lie at the edge of Earth’s solid mantle and liquid outer core, and now scientists think they might be bigger than we ever imagined. According to previous estimates, the two largest blobs would be 100 times larger than Mount Everest if they were drawn to the surface of the planet. But after studying decades of seismic data from earthquakes, scientists now believe that the large drop under the Pacific Ocean could actually be far more monstrous. For example, a new structure discovered along the edge of the drop was over 620 miles (1,000 kilometers) in diameter.
Lost North Sea Islands weathered massive tsunami
About 8,000 years ago, a tsunami struck a plain between Britain and the Netherlands, submerging most of the region. But research suggests that some islands may have resisted the tsunami, providing a home for Stone Age humans for thousands of years. Although they remained above the water for some time after the tsunami, rising sea levels eventually submerged the islands some 1,000 years later. Scientists have learned that the Lost Islands only survived the tsunami after collecting sediment from the seabed near the eastern English estuary of the River Ouse.
Earth’s core is a billion years old
The solid inner core of the Earth – a ball of iron 1,500 miles wide (2,442 km) – probably formed around 1 billion to 1.3 billion years ago, say scientists. By recreating the conditions found in the nucleus on a very small scale, the team were able to calculate how long it would take for a drop of molten iron to reach the current size of the nucleus. The time window of about 1 billion years fits perfectly with historical fluctuations in the planet’s magnetic field, which strengthened considerably between 1 billion and 1.5 billion years. The crystallization of the inner core may have provided this surge of magnetism, since the process would have released heat in the liquid outer core; the heat causes a churning movement in the liquid which then feeds the magnetic field.
Related: Earth’s core is a billion years old
Piece of a lost continent found beneath Canada
Around 150 million years ago, a now-lost continent shattered into huge fragments – and a large chunk was recently discovered lurking under Canada. Scientists made the discovery while studying a type of diamond-bearing volcanic rock called kimberlite, which had been collected nearly 400 km below Baffin Island in northern Canada. The kimberlite’s mineral chemistry matched that of the long-lost continent, making the sample location the deepest point where evidence of the continent has ever been found.
Underwater rivers found near Australia
This year, scientists discovered massive rivers of cold salt water flowing from the Australian coast into the deep ocean. Rivers, which researchers discovered using autonomous underwater vehicles, form when shallow waters near the coast lose heat during the winter. Evaporation during the summer months makes this shallow water saltier than deep water. So when it cools, the dense, salty water flows and winds through the ocean like an underwater river. These rivers stretch for thousands of kilometers and carry nutrients, plant and animal matter, and pollutants into the ocean.
Ancient rainforest discovered under Antarctic ice
Antarctica may be the last place you’d expect to find remains of an ancient rainforest, but that’s exactly what scientists found under the western side of the continent. The remains of the forest were discovered in a sediment core drilled into a seabed near the Pine Island Glacier. A layer of sediment inside the core stood out from the rest, as its color differed markedly from those around it; upon closer inspection, scientists found ancient pollen, spores, pieces of flowering plants, and a network of roots in the layer. The sample dated back 90 million years, to the mid-Cretaceous, when the now frozen Antarctica had a much milder climate.
Ancient seabed buried 400 miles beneath China
A seabed that once bordered the bottom of the Pacific Ocean has been found buried hundreds of kilometers under China, where it continues to descend towards the transition zone of the Earth’s mantle. The rock plate once stood at the top of the oceanic lithosphere, the outermost layer of the Earth’s surface, but was pushed down when it collided with a nearby tectonic plate, in which this is called a subduction event. Scientists have never detected a subduction event so deep below the planet’s surface, at depths between 254 and 410 miles (410 to 660 km) underground.
Is the lost tectonic plate resurrected?
Scientists digitally reconstructs a tectonic plate and showed that its movement probably gave rise to an arc of volcanoes in the Pacific Ocean around 60 million years ago. In the past, some geophysicists have argued that the plate, known as the Resurrection, never existed. But if it existed, the plate would have been pushed under the earth’s crust tens of millions of years ago; thus, using computer reconstruction, the scientists reversed this movement, virtually pulling it and other ancient plaques to the surface. They found that the resurrection would fit in like a perfect puzzle piece, just east of two plates called Kula and Farallon, and its edge matches the ancient volcanic belts of Washington state and Alaska.
The imposing coral structure eclipses the Empire State Building
The first detached coral reef discovered in over 100 years is taller than the Empire State Building. Measuring 500 meters high from base to tip, the Coral Tower stands freely near the rest of the Great Barrier Reef off the coast of Australia. The blade-like structure is 1 mile (1.5 km) wide at its base, and its top is approximately 130 feet (40 m) below the sea surface.
Originally posted on Live Science.