A new study by American researchers concluded that in the mantle layer that lies between the crust and the core, there are vast reserves of water, probably three times the total volume of water of all oceans on the surface of our planet.
This “reservoir” of water, which seems to be stable over time, lies at a depth of up to 700 kilometers beneath the planet’s surface, in the intermediate zone between the upper and the lower mantle.
The researchers, led by geophysicist Steven Jacobsen of the Northwestern University and seismologist Brandon Schmandt of the University of New Mexico, estimate that water is “locked” (molecularly trapped) in a mineral called ringwoodite.
This is a relatively rare crystalline structure with a rock formed from olivine under very high pressures and temperatures.
The existence of such large quantities of ground water sheds new light on the hydrological cycle of the Earth and the origin of the seas and oceans, since they have more or less maintained their size over millions of years. Some geologists believe that water on Earth came from space or, in particular, from icy comets that fell on our planet. But the new discovery reinforces the alternative possibility that the oceans gradually emerged from the depth of the early Earth, thanks to the continuous recycling of tectonic plates. “The indications show that the Earth’s water came from inside,” said Jacobsen.
The U.S. researchers used more than 2,000 seismographs to study seismic waves that provoked over 500 earthquakes in the USA. By measuring the propagation velocity of underground seismic waves at different depths, the scientists identified the density and therefore the type of rocks that were passed by the waves.
The ‘well hidden’ water was discovered because its presence slowed down the seismic waves in the corresponding layers (a seismic wave takes longer to penetrate a hydrated rock than an anhydrous one).
The seismic observations are supplemented by laboratory experiments, from which the researchers concluded that hydrated ringwoodite at depths of around 700 km acts like a “sponge” that is gradually melting under high pressure and temperature and traps the previously absorbed water in the transition zone. “When a rock with a lot of H2O moves from the transition zone to the lower mantle it needs to get rid of the H2O somehow, so it melts a little bit. This is called dehydration melting,” said Brandon Schmandt.
Although the study concerns only the territory of the U.S., the researchers believe that something similar is happening around the world and are already planning to expand the study to other countries. The study is published in the Journal Science.
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Original study: http://www.sciencemag.org/content/344/6189/1265
Palestinian Writer Kicked Out of His Neighborhood by Israelis for Viral CNN, MSNBC Interviews
A prominent Palestinian writer has been expelled from his home after delivering a powerful message about the actions of Israeli occupation forces on CNN and MSNBC.
As Israel continues to back the theft of homes by illegal Jewish settlers in Jerusalem, it has delivered harsh blows against the civilian population of the Gaza Strip, resulting in about 1,000 injured and a fast-rising civilian death toll of at least 139 Palestinians.
Mohammed El-Kurd, a Palestinian writer and activist who resides in Sheikh Jarrah, has been making appearances this week to discuss his personal experience of the wave of dispossessions and displacements enforced by Israeli authorities in Palestinian neighborhoods. His powerful interviews have gone viral.
As punishment for speaking to the international press about his people’s plight, El-Kurd was removed from his own neighborhood by Israeli military forces.
In the video, a woman can be heard pleading in Arabic for the soldiers to “leave him” while El-Kurd defiantly challenged the soldiers: “Hit me! Hit me!”
The expulsion of El-Kurd from his neighborhood is believed to be a direct result of his outspoken and blunt discussion of what he describes to CNN as “the violent dispossession” of Palestinian families.
He also described the forced eviction of Palestinians from their ancestral land as “forced ethnic displacement,” despite Israeli courts’ legal claims. El-Kurd pointed out that international law does not grant legal jurisdiction to Israeli courts over occupied East Jerusalem or the ability to evict Palestinians from their homes.
In a separate interview with MSNBC, the write blasted the Israelis for resorting to “supremacist, colonial judicial system” that works with civilian organizations to remove Palestinian Arab residents from their homes and replace them with Jewish settlers, many of whom hail from Europe and the United States.
“Today the difference we have is that they no longer use their artillery to steal our homes except when they do come and steal their homes,” he said. “Now they use a supremacist, colonial judicial system that colludes with organizations to take our homes. Just because it’s legal doesn’t mean it’s moral or correct or historically just. What’s happening to us is ethnic cleansing.”
Despite the traumatic experience of being expelled from his home, El-Kurd later tweeted that he was “fine & unintimidated.”
On Friday, the United Nations said that it believes that some 10,000 Palestinians have been forced to abandon their homes amid the escalating offensive by Israeli forces.
WATCH: Video Shows Bullets Fly as Armored Car Crew Narrowly Escapes Brutal Heist
Dramatic dash cam footage from Pretoria, South Africa, shows the moment that the crew of an armored car narrowly escaped an attempt by armed robes to stage a heist.
The shocking video shows a pair of private security officers transporting cash in a bulletproof Toyota truck on April 22 before they suddenly come under attack by armed assailants.
For the first minute of the roughly three-minute-long video, the security guards can be seen routinely driving down a highway.
The vehicle then comes under fire as bullets can be heard slamming into the driver side of the car, with the window by the driver’s side shattering.
The driver, who maintains his calm and composure during the attack, manages to escape amid the traffic. He also seems to slam into one of the two vehicles belonging to the attackers.
“They’re going to shoot. They’re going to f**king shoot,” the driver then says, urging his colleague to pull out the rifle and prepare to defend their lives.
As gunshots continue to ring out, the two drive silently as the tension builds. The driver then shouts to his colleague: “Phone Robbie, phone Josh! Ask them where they are.”
As the video ends, the driver can be seen stopping the vehicle and grabbing his colleague’s rifle. At that point, it becomes clear that the assailants have realized that their attack was futile they had already fled the scene.
“The suspects fired several shots at the [Cash-In-Transit] vehicle in an attempt to stop it during a high-speed chase,” said police spokesperson Brigadier Vishnu Naidoo , reports News24.
“The driver of the CIT vehicle managed to evade the robbers for a while but later stopped in wait for the robbers,” Naidoo added. “The robbers fled without taking any money. No arrests have yet been made.”
Online users have praised the steel nerves of the armored car’s crew in navigating what could have been a deadly attack.
After Strong Backlash, NYPD Kicks Robotic Dog “Spot” to the Curb
The New York City Police Department decided this week to stop leasing a robotic dog from Boston Dynamics following a sustained outcry from residents and lawmakers, who denounced the use of the high-tech, four-legged device in low-income neighborhoods as a misallocation of public resources and violation of civil liberties.
When the NYPD acquired the K-9 machine last August, officials portrayed “Digidog”—the department’s name for the camera-equipped, 70-pound robot—as “a futuristic tool that could go places that were too dangerous to send officers,” the New York Times reported earlier this week.
Inspector Frank Digiacomo of the department’s Technical Assistance Response Unit said in a television interview in December: “This dog is going to save lives. It’s going to protect people. It’s going to protect officers.”
Instead—thanks to strong backlash from critics, including people who live in the Bronx apartment complex and the Manhattan public housing building where the robotic dog was deployed in recent weeks—the department is returning “Spot,” as Boston Dynamics calls the device, months earlier than expected.
According to the Times:
In response to a subpoena from City Councilman Ben Kallos and Council Speaker Corey Johnson requesting records related to the device, police officials said that a contract worth roughly $94,000 to lease the robotic dog from its maker, Boston Dynamics, had been terminated on April 22.
John Miller, the police department’s deputy commissioner for intelligence and counterterrorism, confirmed on Wednesday that the contract had been canceled and that the dog had been returned to Boston Dynamics or would be soon.
Miller told the Times that the police had initially planned to continue testing the K-9 machine’s capabilities until August, when the lease had been scheduled to end.
“Robotic surveillance ground drones are being deployed for testing on low-income communities of color with under-resourced schools,” Rep. Alexandria Ocasio-Cortez (D-N.Y.) tweeted in response. “Please ask yourself: when was the last time you saw next-generation, world class technology for education, healthcare, housing, etc. consistently prioritized for underserved communities like this?”
And earlier this month, as Common Dreams reported, footage of the robotic dog walking through a Manhattan public housing building went viral, sparking additional outrage and prompting a city council investigation.
“Why the hell do we need robot police dogs?” Rep. Jamaal Bowman (D-N.Y.) asked at the time.
While there are “people living in poverty, struggling to put food on the table, keep a roof over their head, take care of their kids, afford child care—all this going on, and now we got damn robot police dogs walking down the street,” Bowman lamented.
Bill Neidhardt, a spokesperson for New York City Mayor Bill de Blasio, who urged the police department to reconsider its use of the robot following objections from residents and lawmakers, said he was “glad the Digidog was put down.”
“It’s creepy, alienating, and sends the wrong message to New Yorkers,” Neidhardt said.
Republished from CommonDreams.org under Creative Commons