Tag: Geology

The Eruption Of Kilauea Could Be So Terrifyingly Deadly

A “short-lived explosion” on May 9, 2018, caused by rocks falling into the lava lake. The lava lake is still above the water table at this point.

Hawaii’s Kilauea volcano has already shocked the world by sending massive walls of lava into houses and eating up cars, and spreading acid rain across the island. But that might just be the beginning.

Experts fear that the complex system underneath the volcano could be about to reach a new stage, which could see a blanket of ash and boulders the size of fridges thrown out of the volcano.

If those things are thrown out, they could easily kill the people below them. As such, people are being advised to stay out of closed areas of the national park that surrounds the volcano, where they should be safe.

If it goes up, it will come down,” said Charles Mandeville. “You don’t want to be underneath anything that weighs 10 tons when it’s coming out at 120 mph (193 kph).

The explosion will be so dramatic because of the structure of the volcano. Recent events have been changing the make-up of the volcano – and bringing about the explosive situation.




The lava lake in the volcano is in a rapid retreat – as shown in pictures released by the USGS this week. If it keeps going down, as it has done quickly, then it could trigger a run of events that would bring about ballistic effects.

In little more than a week, the top of the lava lake has gone from spilling over the crater to almost 970 feet (295 meters) below the surface as of Thursday morning, Mandeville said.

The lava levels in the lake are dropping because lava is spewing out of cracks elsewhere in the mountain, lowering the pressure that filled the lava lake.

The fear is that it will go below the underground water table — another 1,000 feet further down — and that would trigger a chain of events that could lead to a “very violent” steam explosion, Mandeville said.

At the current rate of change, that is about six or seven days away.

Once the lava drops, rocks that had been superheated could fall into the lava tube. And once the lava drops below the water table, water hits rocks that are as hot as almost 1,200-degrees Celsius and flashes into steam.

When the water hits the lava, it also steams. And the dropped rocks hold that steam in until it blows.

A similar 1924 explosion threw pulverized rock, ash and steam as high as 5.4 miles into the sky, for a couple of weeks.

If another blast happens, the danger zone could extend about 3 miles around the summit, land all inside the national park, Mandeville said.

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Rare Blue Diamond Found In South Africa’s Cullinan Mine

The 29.6-carat stone was recovered by Petra Diamonds at its Cullinan mine, about 40km (25 miles) north-east of Pretoria.

This stone is one of the most exceptional stones recovered at Cullinan during Petra’s operation of the mine,” the company said.

Petra unearthed a 25.5 carat blue diamond which sold for $16.9m (£10.3m) in 2013. The latest discovery is also expected to sell for a high price.




The stone is an outstanding vivid blue with extraordinary saturation, tone and clarity, and has the potential to yield a polished stone of great value and importance,” Petra said in a statement on Tuesday.

Cullinan mine has produced hundreds of large stones and is famed for its production of blue diamonds – among the rarest and most highly coveted of all diamonds.

The mine was acquired in 2008 by Petra Diamonds, which also operates in Botswana and Tanzania.

A similar 26.6-carat blue rough diamond discovered by the company in May 2009 was cut into a near perfect stone and fetched just under $10m at a Sotheby’s auction.

The Cullinan mine is famed for the production of blue diamonds

Another deep-blue diamond from Cullinan was auctioned for $10.8m in 2012 and set a world record for the value per carat.

The largest ever rough gem diamond was discovered at the Cullinan mine in 1905 and was presented to the British monarch Edward VII.

The 3,106-carat stone was then cut, with two of the principal diamonds forming part of the British crown jewels – the 530-carat First Star of Africa and the Second Star of Africa at 317 carats.

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Could Underwater Sound Waves Be The Key To Early Tsunami Warnings?

Mathematicians think they have devised a way of calculating the size and force of a tsunami in advance of it hitting land, which can help early detection.

Experts say naturally occurring high-speed acoustic gravity waves are created after “tsunami trigger events”.

Cardiff University scientists hope to make a real-time early warning system.

Alaska was under a tsunami warning earlier this week after a 7.9-magnitude earthquake struck 280km (173 miles) off the coast of the American state.

The deadliest recorded tsunami was the 2004 Boxing Day Indian Ocean tsunami, which killed almost 230,000 people in 11 different countries.




But scientists in Cardiff hope to help give extra warning time for tsunamis by using the fast-moving underwater sound waves.

By taking measurements of acoustic gravity waves, we basically have everything we need to set off a tsunami alarm,” said Dr Usama Kadri, lead author for the study from Cardiff University’s school of mathematics.

Underwater earthquakes are triggered by the movement of tectonic plates on the ocean floor and are the main cause of tsunamis.

Scientists say sound waves can travel over 10 times faster than tsunamis and spread out in all directions, regardless of the trajectory of the tsunami, making them easy to pick up using standard underwater hydrophones.

They say this is an ideal source of information for early warning systems.

In a new study published in the Journal of Fluid Mechanics, Cardiff University scientists show how the key characteristics of an earthquake – such as its location, duration, dimensions, orientation and speed – can be determined when the gravity waves are detected by a single hydrophone in the ocean.

The sound waves move through the deep ocean at the speed of sound and can travel thousands of meters below the surface.

Tsunamis are currently detected by floating buoys that are able to measure pressure changes in the ocean caused by tsunamis.

However, experts say the technology relies on a tsunami physically reaching the buoys.

The current technology also requires the distribution of a huge number of expensive buoys in oceans all around the world.

Though we can currently measure earthquakes using seismic sensors, these do not tell us if tsunamis are likely to follow,” Dr Kadri continued.

Using sound signals in the water, we can identify the characteristics of the earthquake fault, from which we can then calculate the characteristics of a tsunami. Since our solution is analytical, everything can be calculated in near real-time.

Our aim is to be able to set off a tsunami alarm within a few minutes from recording the sound signals in a hydrophone station.

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Anthropocene: We Might Be About To Move From The Holocene To A New Epoch

After 11,700 years, the Holocene epoch may be coming to an end, with a group of geologists, climate scientists and ecologists meeting in Berlin this week to decide whether humanity’s impact on the planet has been big enough to deserve a new time period: the Anthropocene.

The term, coined in the 1980s by ecologist Eugene F. Stoermer, takes its prefix from the Ancient Greek word for human because its proponents believe the influence of humanity on the Earth’s atmosphere and crust in the last few centuries is so significant as to constitute a new geological epoch.




The Anthropocene Working Group assembles in Berlin on Friday, an interdisciplinary body of scientists and humanists working under the umbrella of the International Commission on Stratigraphy and “tasked with developing a proposal for the formal ratification of the Anthropocene as an official unit amending the Geological Time Scale“.

The 30-strong group, which includes a lawyer, has outlined two key questions which it will address during deliberations at the Haus der Kulturen der Welt:

How does the recent cognition of the immense quantitative shift in the biophysical conditions of the Earth affect both scientific research and a political response to these changes?”

And “Does the Anthropocene also pose a profound qualitative shift, a paradigm shift for the ways in which science, politics, and law advance accordingly?”

Following the Pleistocene, we have for the last 11,700 years lived in the Holocene epoch, which is characterized by the warmer and wetter conditions that came after the end of the last ice age and has seen humans establish new territories and the Earth’s population soar.

Many scientists are happy with the Holocene as a term, but after Nobel Prize-winning atmospheric chemist popularized the “Anthropocene” at the turn of the millennium it refuses to go away and the ICS has deemed it in need of serious debate.

Based around a series of presentations by members of the AWG and statements from invited speakers from the humanities, the social sciences, and political fields, the forum will “discuss both the extraordinary changes to the Earth system as well as its consequences in setting new agendas for governing, researching, and disseminating crucial knowledge.”

The group has given itself until 2016 to come up with a proposal to submit to the ISC, which ultimately determines what time period we live in.

This might seem like a long way away, but when you consider the earliest epoch, the Paleozoic, began approximately 541 to 252 million years ago, it’s just a speck in the Earth’s history.

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Earth Will Be Rocked By A Year Of Devastating Earthquakes

earthquake roation

DEVASTATING earthquakes could be on the rise next year as the rotation of Earth slows down, scientists have warned.

The speed of Earth’s rotation fluctuates extremely mildly – extending or decreasing the length of a day by a millisecond – but this tiny deceleration could have devastating consequences.

Scientists have warned if the rotation slows it could lead to more major earthquakes.

Research from Roger Bilham of the University of Colorado in Boulder and Rebecca Bendick of the University of Montana in Missoula looked at earthquakes with a magnitude higher than seven since 1900.




The duo found five years since the turn of the 20th century where there were significantly more 7.0 earthquakes – all of which were years that earth’s rotation speed had slowed down slightly.

Prof Bilham told the observer: “In these periods, there were between 25 to 30 intense earthquakes a year.“The rest of the time the average figure was around 15 major earthquakes a year.”

And in 2018, the Earth’s rotation speed is set to slow down leading to a jump on the six magnitude seven or higher quakes we have had this year.

Prof Bilham said: “The correlation between Earth’s rotation and earthquake activity is strong and suggests there is going to be an increase in numbers of intense earthquakes next year.”

earthquake

The inference is clear. Next year we should see a significant increase in numbers of severe earthquakes.”

We have had it easy this year. So far we have only had about six severe earthquakes. We could easily have 20 a year starting in 2018.

Exactly why a decrease in rotation speed can lead to more major earthquakes is unclear, but experts believe it could be down to changes in the Earth’s core which ultimately has an effect on the surface.

The team also could not say exactly where the earthquakes will occur, but Bilham suggests that a slower rotation speed will lead to more tremors on and around the equator – such as South America, New Zealand and other places that sit on top of the Ring of Fire.

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Ancient Skull May Be History’s Earliest Known Tsunami Victim

In 1929, an Australian geologist named Paul S. Hossfeld was investigating the northern coast of Papua New Guinea for petroleum.

He found bone fragments embedded in a creek bank about seven miles inland and about 170 feet above sea level.

At first, Dr. Hossfeld believed that the specimen was from the skull of Homo erectus, an extinct relative of modern humans. Later analysis would show it belonged to a modern human who lived about 6,000 years ago.

Now recent research suggests the remains known as the Aitape skull could be something more: the earliest known victim of a tsunami.

The findings, published Wednesday in the journal PLoS One, may offer useful historical context for how ancient humans living along the Pacific Ocean’s coasts faced fierce natural hazards.

Here we start to see human interaction with some nasty earthquakes and tsunamis,” said James Goff, a retired geologist at the University of New South Wales Sydney and author of the study.




Papua New Guinea occupies the eastern half of a large, bountiful island just north of Australia (the western side is part of Indonesia).

In 1998, after decades of relative geological quiet, a devastating tsunami rocked the country, killing more than 2,000 people.

This huge volume of water struck the coast and swept away everything,” said John Terrell, an anthropologist at the Field Museum in Chicago who has completed research in the country and is a co-author on the paper.

The villages I knew and loved were sheared off.

After struggling for almost two decades to get funding for the project, he returned to the island in 2014 to explore the rain forests and crystal clear creek where Dr. Hossfeld had discovered the skull 85 years earlier.

Dr. Hossfeld had left detailed notes about where he had found the skull, which helped guide Dr. Goff and his team as they collected samples from the same sediment layer at a nearby river-cut cliff.

Back at the lab, they performed geochemical analysis to determine whether the sediment level had been deposited by a tsunami 6,000 years ago.

Because they had previously analyzed geochemical signals from sediment on the island following the 1998 tsunami, the team knew which clues to look for, like grain size and composition.

They found that the sediment collected from the skull site contained fossilized deep sea diatoms. These microscopic organisms were a telltale sign that ocean water had drowned the area at some point.

The researchers also found geochemical signals that matched the signatures they collected in 1998, offering additional evidence that a tsunami had struck around 6,000 years ago.

Bang! Right where the diatoms were looking very sexy and you’re getting excited, you have a signal that says, ‘Hi, I’m seawater,’” said Dr. Goff.

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Mountain Forest Growth Has Established The Earth’s Climate For Millions Of Years

The Earth’s atmospheric carbon dioxide has remained remarkably stable over the past 24 million years.

And scientists believe they have now solved part of the mystery as to why this has been the case, despite changing geological conditions.

They believe that ancient tree roots in the mountains may play an important role in controlling long-term global temperatures acting as a type of natural ‘thermostat’.

When CO2 levels became too low for plants to grow properly, forests in mountains appear to have kept the climate in check by slowing down the removal of carbon dioxide from the atmosphere.




This study shows how trees can act as brakes on extreme climate change, and the roots of trees in tropical mountains such as the Andes play a disproportionate role,” Yadvinder Malhi, professor of Ecosystem Science at Oxford University said.

However, these responses take thousands to millions of years and cannot do much to slow the rate of global warming we are experiencing this century.

Researchers from Oxford and Sheffield Universities discovered that temperatures affect the thickness of the leaf litter and organic soil layers, as well as the rate at which the tree roots grow.

In a warmer world, this means that tree roots are more likely to grow into the mineral layer of the soil, breaking down rock which will eventually combine with carbon dioxide.

This process, called weathering, draws carbon dioxide out of the atmosphere and cools the planet.

The theory suggests that mountainous ecosystems have acted like the Earth’s thermostat, addressing the risk of ‘catastrophic‘ overheating or cooling over millions of years.

In their research paper, published online in Geophysical Research Letters, the researchers carried out studies in tropical rain forests in Peru.

They measured growth of the tree roots across different sites of varying altitude – from the warm Amazonian Lowlands to the cooler mountain ranges of the Andes- every three months over several years.

At each of the sites, they also measured the thickness of the organic layer above the soil.

This information was then combined with data of monthly temperature, humidity, rainfall, and soil moisture to calculate the likely breakdown process of the basalt and granite rocks found in the mountain ranges of Peru.

Using this model, scientists were able to scale up their results to calculate the likely contribution of mountain forests worldwide to global weathering rates.

The researchers then calculated the likely amount of carbon to be pulled out of the atmosphere through weathering when the Earth became very hot.

They looked at the volcanic eruptions in India 65 million years ago, known as the Deccan traps.

The model also allowed them to calculate the weathering process and carbon feedback after the Earth’s cooling 45 million years ago, when great mountain ranges like the Andes and the Himalayas were first formed.

The paper suggests that mountainous regions may play a particularly important role in drawing carbon out of the atmosphere because they have abundant volcanic rock which is highly reactive to weathering when it disintegrates.

This is a simple process driven by tree root growth and the decomposition of organic material,” said lead researcher Chris Doughty, from Oxford University.

Yet it may contribute to Earth’s long-term climate stability. It seems to act like a thermostat, drawing more carbon dioxide out of the atmosphere when it is warm and less when it is cooler.

A series of climatic events over the last 65 million years ago have resulted in global temperatures rising and falling.

However, the weathering process that regulates carbon dioxide in the atmosphere may be buffered by forests that grow in mountainous parts of the world.

In the past, this natural process may have prevented the planet from reaching temperatures that are catastrophic for life.

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A New Study Shows That The Moon’s Interior Could Contain Water

moon

The moon might be flowing with much more water than we thought, thanks to ancient volcanic deposits, a new study shows.

Using satellite data, scientists from Brown University studied layers of rock on the moon that likely formed from large volcanic eruptions, called lunar pyroclastic deposits.




The magma created by these eruptions has been carried to the moon’s surface from very deep within its interior, the study showed. But water on the moon isn’t new – in fact, it’s had a pretty bonkers past.

For a long time, scientists thought that the moon was dry, because of how it was formed. According to the “giant impact” theory, the moon was born 4.5 billion years ago when an object rammed into the Earth.

The new moon was an ocean of magma, and researchers thought there was no way a moon that hot could have retained water.

moon

Then the Apollo astronauts brought back samples from the moon, including little glass beads. They did contain trace amounts of water, but for a while it was assumed to be water from Earth that had gotten mixed in by accident.

So scientists got more specimens, and studied them closely. Fast-forward a few decades, and we know there’s a bit of water on the moon.

Previous studies have shown that there are some traces of ice in shadowed regions at the moon’s poles, which may have been the result of hydrogen that comes from solar wind.

moon

What’s interesting about this new study, though, is that it shows the water is far more than just ice hiding in shadowy areas of the moon. In fact, there are likely pools of water in the moon’s mantle, as well.

And it gets weirder. If there’s water in the moon’s mantle, that suggests that the water was delivered to the moon very early in its formation, before it fully solidified, the study’s lead author, Ralph Milliken.

Because the magma originally comes from deep within the lunar interior, Milliken explains, “the deep interior of the moon must also contain water.”

moon

Evidence of lunar water could also make moon missions much more plausible. Water is heavy and expensive to transport from earth to space, so if there’s already water on the moon, it opens up a lot of possibilities for a longer-term human presence.

The scientists, plan to map the pyroclastic deposits in order to better understand how the water concentrations differ on the moon – and might even target those places for future explorations.

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