Scientists believe diamonds are under Earth’s surface

According to a team of scientists, there may be quadrillion tons of diamonds under the surface of Earth.

According to an international team of scientists, there may be quadrillion tons of diamonds under the surface of the Earth. The deposits are in cratonic roots between 90 and 150 miles below the surface.

“This shows that diamond is not perhaps this exotic mineral, but on the (geological) scale of things it’s relatively common,” said Ulrich Faul, co-author of the study and a research scientist at MIT. They discovered there is much more diamond than they ever thought there could be.

MIT News describes cratons as the oldest and most immovable sections of rock. They are stable chunks of the Earth’s crust and are in the shape of inverted mountains.

The deepest parts are the roots that can reach all the way to the Earth’s mantle. The authors of the study believe the diamonds are in the mantle.

They used seismic data – or recorded sound waves from seismic activity to locate the diamonds. This data helped them measure what the Earth is made of.

Then, the team used 3D modeling to create virtual rocks in a quest to figure out what substances could compose the roots of cratons. Diamonds seemed to foot the bill.

The diamonds matched the velocity of the sound traveling through the roots. They estimated that the roots must be made of 1 to 2 percent diamond.

Using this estimate, and the number of known craton roots, the scientists arrived at their quadrillion-ton estimate. It is 1,000 times more than they first thought.

 

Study reveals new clues about Great Dying, Earth’s largest mass extinction

A new study sheds light on the potential cause of the End-Permian Extinction 250 million years ago.

A new study sheds light on the causes of the largest mass extinction in the Earth’s history, also referred to as the End-Permian Extinction and the Great Dying.

The event took place approximately 250 million years ago when a giant volcanic eruption hit what is now Russia’s province of Siberia. The eruption sent almost 90 percent of life into extinction. In geology, the eruption is referred to as the Siberian Flood Basalts, which ran for nearly one million years.

“The scale of this extinction was so incredible that scientists have often wondered what made the Siberian Flood Basalts so much more deadly than other similar eruptions,” said Michael Broadley of the Centre for Petrographic and Geochemical Research in Vandœuvre-lès-Nancy, France, and lead author of the study.

The research was co-authored by the late Lawrence Taylor, who is the former director of the Planetary Geosciences Institute at the University of Tennessee, Knoxville.

“Taylor was instrumental in supplying samples of mantle xenoliths, rock sections of the lithosphere [a section of the planet located between the crust and the mantle] that get captured by the passing magma and erupted to the surface during the volcanic explosion,” Broadley said. “Taylor also provided advice throughout the study.”

The team analyzed samples to determine the lithosphere composition, which revealed that prior to the Siberian Basalt floods, it was loaded with bromine, iodine, and chlorine, all of which belong to the halogen chemical group. After the volcanic eruption, they disappeared.

“We concluded that the large reservoir of halogens that was stored in the Siberian lithosphere was sent into the earth’s atmosphere during the volcanic explosion, effectively destroying the ozone layer at the time and contributing to the mass extinction,” Broadley said.

The findings were published in Nature Geoscience.

Plate tectonics are not necessary for human life, study says

A new study suggests that plate tectonics might not be needed to support life, which contradicts previous beliefs.

With recent research suggesting that our universe contains more habitable planets than we thought, a new study suggests that plate tectonics are not necessary.

Scientists often used biosignatures of carbon dioxide in the search for habitable planets. Atmospheric carbon dioxide typically increases the Earth’s surface heat via the greenhouse effect, and carbon makes its way from the subsurface to the atmosphere due to natural processes.

“Volcanism releases gases into the atmosphere, and then through weathering, carbon dioxide is pulled from the atmosphere and sequestered into surface rocks and sediment,” said Bradford Foley, co-author of the study. “Balancing those two processes keeps carbon dioxide at a certain level in the atmosphere, which is really important for whether the climate stays temperate and suitable for life.”

And since most of our planet’s volcanoes are located at tectonic plate borders, scientists previously believed that they were needed for life. But using a computer model of planetary lifecycles, the team examined how much heat planets can retain based on the amount of heat and heat-producing elements at the moment of planet formation.

Hundreds of simulations later, and the team found that stagnant lid planets can maintain liquid water conditions for billions of years. At the most, up to 4 billion years, which is the Earth’s current approximate life span.

“You still have volcanism on stagnant lid planets, but it’s much shorter lived than on planets with plate tectonics because there isn’t as much cycling,” Smye said. “Volcanoes result in a succession of lava flows, which are buried like layers of a cake over time. Rocks and sediment heat up more the deeper they are buried.”

The findings were published in Astrobiology.

Scientists discover primary source of Mars dust

A new study suggests the primary cause of the dust storm on Mars.

Scientists believe that they have found the source of the dust storm that put one of NASA’s rovers into hibernation, pointing to the 600-mile-long (1,000-kilometer) Medusae Fossae Formation located near the planet’s equator.

The recent study suggests that the wind-eroded Medusae Fossa is the biggest source of dust on Mars, and has its origins in ancient volcanic activity.

“Mars wouldn’t be nearly this dusty if it wasn’t for this one enormous deposit that is gradually eroding over time and polluting the planet, essentially,” said study co-author Kevin Lewis from Johns Hopkins University.

Although meteor craters are common on Mars, the fragments that stem from impacts are usually bigger than the particles that make up Martian dust.

“How does Mars make so much dust, because none of these processes are active on Mars?” asked lead author Lujendra Ojha, referring to common dust-creating processes. Although there are factors in the current storm that have played played similar roles in the past, the team believes that something else is the primary cause for the dust storms.

By examining the dust’s chemical combination and studying data from the Mars Odyssey spacecraft, the team was able to pinpoint the Medusae Fossa as the location with chlorine and sulfur ratios that match those found in the Mars dust.

“Dust everywhere on the planet is enriched in sulfur and chlorine and it has this very distinct sulfur-to-chlorine ratio,” Ojha said.

Although seasonal dust storms are commonplace on Mars, taking place each year, global dust storms typically occur every 10 years or so.

“It just explains, potentially, one big piece of how Mars got to its current state,” Lewis said.

The findings were published in Nature Communications.

Earth might be harboring a quadrillion tons of diamonds

Researchers believe that there are more than a quadrillion tons of diamonds more than 100 miles underneath the surface of the Earth’s interior.

A new study from MIT researchers in collaboration with other universities suggests that there could be over a quadrillion tons of diamonds underneath the Earth’s interior. However, the minerals are buried over 100 miles underneath the surface, which is deeper than any drilling missions have ever reached.

Researchers estimate that the cratonic roots—the oldest, most immovable portions of rock located beneath the center of most continental tectonic plates—could contain 1 to 2 percent diamond.

“This shows that diamond is not perhaps this exotic mineral, but on the [geological] scale of things, it’s relatively common,” said Ulrich Faul, a research scientist from MIT’s Department of Earth, Atmospheric, and Planetary Sciences. “We can’t get at them, but still, there is much more diamond there than we have ever thought before.”

“Diamond in many ways is special,” he continued. “One of its special properties is, the sound velocity in diamond is more than twice as fast as in the dominant mineral in upper mantle rocks, olivine.”

The data revealed that a rock with a composition of just 1 to 2 percent diamond would be sufficient to create the higher sound velocities measured by scientists. In addition, this minuscule fraction would not alter the overall density of a craton, which is typically less dense than surrounding mantle rock.

“They are like pieces of wood, floating on water,” Faul said. “Cratons are a tiny bit less dense than their surroundings, so they don’t get subducted back into the Earth but stay floating on the surface. This is how they preserve the oldest rocks. So we found that you just need 1 to 2 percent diamond for cratons to be stable and not sink.”

The findings were published in Geochemistry, Geophysics, Geosystems.

Remnant of ‘fireball’ meteor found in Botswana

Researchers discovered a “fireball” meteor that was the fragment of asteroid 2018 LA first spotted on June 2, 2018.

Researchers just discovered a “fireball” meteor in Botswana’s Central Kalahari Game Reserve (CKGR). It has been confirmed as the fragment of asteroid 2018 LA that was observed in space on June 2, 2018 by the University of Arizona’s Catalina Sky Survey.

“The biggest uncertainty we faced was to determine where exactly the meteorites fell,” said Peter Jenniskens, a subject expert of the Search of Extraterrestrial Intelligence (SETI) Institute in California who assisted in the Botswana search.

After crashing through the Earth’s upper atmosphere, it turned into a meteor fireball and exploded a few seconds later—an event that was observed by Botswana and its neighboring countries.

“As geologists from BIUST we see it as our mandate and duty to respond quickly to events like this one and to recover the material, both for research purposes and as part of the heritage of Botswana,”  said Alexander Proyer, leader of the joint expedition and a member of the Botswana International University of Science and Technology (BUIST).

“The challenge was to search for a meteorite in 200 square kilometers of uncharted wild in a park teeming with elephants, lions and snakes,” he added.

“Meteorites are protected under Botswana law,” said Mohutsiwa Gabadirwe, also of the Botswana Geoscience Institute. “This meteorite is a priceless piece of rock that the people of Botswana will want to enjoy seeing on display for generations to come.”

The SETI Institute is a non-profit foundation that was founded in 1984 to understand, explore, and explain the nature and origin of life in the universe.

Researchers discover world’s oldest colors under Sahara desert

Scientists just discovered the world’s oldest colors under the Sahara desert in Africa.

A team of researchers from The Australian National University (ANU) and overseas facilities have discovered the oldest colors in the world’s geological record in the form of 1.1 billion-year-old bright pink pigments. The pigments were found in rocks located deep under the Sahara desert in Africa.

“The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished,” said Nur Gueneli from ANU and lead author on the study.

In their concentrated form, the fossils range in color from deep purple to blood red. When diluted, they are bright pink.

After crushing the billion-year-old rocks into powder, the team was able to extract and analyze the molecules of the ancient organisms that they harbored inside.

“The precise analysis of the ancient pigments confirmed that tiny cyanobacteria dominated the base of the food chain in the oceans a billion years ago, which helps to explain why animals did not exist at the time,” Gueneli said.

“Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source,” said Jochen Brocks, senior author on the study, who is also from ANU.

“The cyanobacterial oceans started to vanish about 650 million years ago, when algae began to rapidly spread to provide the burst of energy needed for the evolution of complex ecosystems, where large animals, including humans, could thrive on Earth,” he added.

The findings were published in the Proceedings of the National Academy of Sciences.

Japanese orbiter finds lunar cave that could someday house astronauts

As safest location for astronauts, lava tubes could be ideal sites for constructing Moon bases.

The Japanese space agency’s Kaguya spacecraft, which orbited the Moon for nearly two years between 2007 and 2009, imaged a large open lava tube on the lunar surface that could potentially serve as a future habitat for astronauts.

Lava tubes are conduits formed by lava that flowed beneath a hardened surface that has hardened over time.  That surface forms a “roof” that covers the area beneath it, which becomes hollow once the liquid lava stops flowing and drains out of the tunnels it initially created.

Analysis of radar data returned by the spacecraft, also known as Selene, by scientists at the Japan Aerospace Exploration Agency (JAXA) revealed several possible entrances to a lava tube near the Marius Hills region on the Moon.

Space suits are insufficient for protecting astronauts on the Moon from radiation, extreme temperatures, and meteorite impacts, which is why no Apollo astronauts stayed there for more than three days.

The Moon’s lack of both an atmosphere and a magnetic field makes it vulnerable to impacting meteorites.

If astronauts could take shelter in a lava tube or cave, they would be safe from the environmental hazards on the Moon’s surface. This makes these features ideal locations for construction of a lunar base.

“It’s important to know where and how big lunar lava tubes are if we’re ever going to construct a lunar base,” emphasized JAXA senior researcher Junichi Haruyama.

“But knowing these things is also important for basic science. We might get new types of rock samples, heat flow data, and lunar quake observation data.”

Because Kaguya’s radar system was designed to study the Moon’s geology and origin rather than to find lava tubes, the spacecraft did not fly close enough to the Moon’s surface to obtain accurate data about what is present beneath that surface.

To assist them in finding lava tubes from Kaguya’s data, JAXA scientists consulted with their colleagues from NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission, which studied the Moon’s gravitational field from orbit.

Studying GRAIL data, the researchers specifically looked for areas with lower subsurface masses as a means of pinpointing possible lava tubes.

By combining radar data with GRAIL’s gravity data, they were able to determine the depths and widths of the lava tubes and the fact that they comprise a single, larger system, noted GRAIL co-investigator Jay Melosh, who is also a Distinguished Professor of Earth, Atmospheric, and Planetary Sciences at Purdue University.

A lava tube must be several kilometers long and have a height and width of one kilometer at minimum to be detectable by gravity data.

Based on GRAIL findings, the Marius Hills lava tube has enough space to hold one of the US’s larger cities.

Findings of the study have been published in the journal Geophysical Research Letters.