Iceland: could a volcanic period be ahead?

Lava fields of the Reykjanes Peninsula [image credit: Vincent van Zeijst @ Wikipedia]

24th February: ‘Southwestern Iceland was rocked by a series of earthquakes’, reported DW.com. ‘Experts say shocks from the quake, which registered 5.7 in magnitude, sparked increased volcanic activity, triggering a number of aftershocks registering over 4.0 for hours after the initial quake hit.

“It’s an intense activity zone, we are all well aware of that but I’ve never experienced or felt so many strong earthquakes in such a short period of time. It’s unusual,” as the Icelandic Meteorological Office’s (IMO) earthquake hazards coordinator Kristin Jonsdottir told Icelandic public broadcaster RUV.’

The article below appeared five days ago.
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“If an eruption occurs, it would likely mark the beginning of such a [volcanic] period – lasting a few centuries, I believe,” states Magnús Á. Sigurgeirsson, geologist at ÍSOR Iceland GeoSurvey – a consulting and research institute in the field of geothermal sciences and utilization.

“That’s at least how it has been the past three times, and even dating further back, but we don’t have as exact data available on that,” he tells Iceland Monitor.

He is referring to the uncertainty regarding whether an eruption can be expected soon on the Reykjanes peninsula, Southwest Iceland.

Magnús assembled data on the past three volcanic periods in the area. These were 3,000-3,500 years ago, 1,900-2,400 years ago, and finally between the years 800 and 1240 AD.

His information is based on geological maps of the Reykjanes peninsula and on a comprehensive book on volcanic eruptions in Iceland called Nátt­úru­vá á Íslandi, eld­gos og jarðskjálft­ar.

Research reveals that during the latter part of Holocene – a term used to describe a period that began about 11,700 years ago – the volcanic systems on the Reykjanes peninsula have erupted every 900 to 1100 years.

Less is known about the first part of Holocene.

Each eruption period appears to have lasted about 500 years, and during that time most of the volcanic systems appear to have been active, albeit generally not simultaneously. The volcanic activity is characterized by eruptions that each last a few decades. Lava flows from volcanic fissures that can be as long as 12 km (7.5 mi).

On the Reykjanes peninsula, there are six volcanic systems, lined up side by side, pointing from southwest to northeast. Farthest west is that of Reykjanes, then those of Svartsengi, Fagradalsfjall mountain, Krýsuvík, Brennisteinsfjöll mountains and, finally, Hengill mountain.

The last volcanic period began around the year 800 in Brennisteinsfjöll mountains and in the Krýsuvík system, creating the lava fields of Hvammahraun and Hrútafellshraun.

Full article here.
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Update: Lava eruption from long-dormant Icelandic volcano (MARCH 20, 2021) — close to Fagradalsfjall mountain

Earth’s outer shell ballooned during massive growth spurt 3 billion years ago

So the Earth is, or was, a kind of giant balloon. We know seafloor spreading is still ongoing, and can affect global sea levels on historical timescales.
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Ancient fragments of Earth’s crust acted as ‘seeds’ for new crust to grow from, says LiveScience.

Around 3 billion years ago, Earth’s crust ballooned during a massive growth spurt, geoscientists have found.

At that time, just 1.5 billion years after Earth formed, the mantle — the layer of silicate rock between the crust and the outer core that was more active in the past — heated up, causing magma from that layer to ooze into fragments of older crust above it.

Those fragments acted as “seeds” for the growth of modern-day continents.

Doggerland: How did the Atlantis of the North Sea sink?

Hypothetical map of Doggerland [image credit: ancient-origins.net]

This seems semi-topical on the day Britain signs off on its new deal with the EU countries. Going back into history, but not all that far back, the river Thames flowed into the Rhine. North Sea trawlers still find bones of mammoths and other such fossils in their nets today.
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For a long time, scientists believed that a powerful tsunami destroyed Doggerland 8,200 years ago, says DW.com.

Sediment analysis now suggests that the land once connecting Great Britain with the rest of Europe had a later demise.

Around 10,000 years ago, at the end of the last ice age, the sea level in northern Europe was still about 60 meters (197 feet) below what it is today.

The British Isles and the European mainland formed a continuous landmass.

Relatively large rivers crossed this landmass, but in a different way than we know today.

Newly discovered Greenland hot rock mantle plume drives thermal activities in the Arctic

Topographic map of Greenland

We’re told ‘The North Atlantic region is awash with geothermal activity’. Any day now we should be hearing how a few extra molecules of (human-caused) CO2 make the Earth’s innards hotter than they used to be. Or maybe we won’t.
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A team of researchers understands more about the melting of the Greenland ice sheet, says SciTech Daily.

They discovered a flow of hot rocks, known as a mantle plume, rising from the core-mantle boundary beneath central Greenland that melts the ice from below.

Scientists discover volcanoes on Venus are still active

Venus

The presence of sulphur in the atmosphere hinted at this.
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A new study identified 37 recently active volcanic structures on Venus, reports Phys.org.

The study provides some of the best evidence yet that Venus is still a geologically active planet.

A research paper on the work, which was conducted by researchers at the University of Maryland and the Institute of Geophysics at ETH Zurich, Switzerland, was published in the journal Nature Geoscience on July 20, 2020.

“This is the first time we are able to point to specific structures and say ‘Look, this is not an ancient volcano but one that is active today, dormant perhaps, but not dead,'” said Laurent Montési, a professor of geology at UMD and co-author of the research paper. “This study significantly changes the view of Venus from a mostly inactive planet to one whose interior is still churning and can feed many active volcanoes.”

The tsunami that devastated ancient Britain just over 8,000 years ago: new evidence

Position of the Storegga Slide (west of Norway). The yellow numbers give the height of the tsunami wave as tsunamites recently studied by researchers [credit: Lamiot @ Wikipedia] – Mer du Nord = North Sea

The report states: ‘It is thought the tsunami, the largest to hit Northern Europe since the end of the last ice age, happened following a period of global climate change.’
We can only speculate as to the cause(s) of such climate happenings.
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Scientists have found new evidence of a massive tsunami that devastated ancient Britain in the year 6200 BC on the east coast of England, reports the Daily Mail.

The giant tsunami event, known as the Storegga Slide, was caused when an area of seabed the size of Scotland – around 30,000 square miles – under the Norwegian Sea suddenly shifted.

New geological evidence reveals three successive waves tore across an ancient land bridge connecting Britain with the rest of Europe, known as Doggerland, now submerged beneath the North Sea.

There are two faces of the Earth: study

Pacific ‘ring of fire’

Recent research has also found why changes to Earth’s magnetic field are weaker over the Pacific.
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Earth’s mantle is currently classified into two main domains, African and Pacific.

However, little is known about their formation and history, and they are commonly assumed to be chemically the same, says Tech Explorist.

In a new study by Curtin University, scientists studied chemical and isotopic “make-up” of rocks sourced from thousands of kilometers below the surface.

Mysterious lights seen: Geomagnetic Link to earthquakes?

This twitter video caught my eye last night, it was taken near Miami a few nights ago. It shows mysterious lights, confirmed from many sources and featured on national US TV channels where it’s reported answers are being demanded from the Pentagon.

UFO sighting in Miami last night‼️ 👽 pic.twitter.com/db9ONEY0Bm

— Miami WTF⚠️ (@miami_wtf) June 24, 2020

Then today my physicist friend Mike McCulloch posted a tweet about some similar phenomena which have been observed for many years in Norway.

Hundreds of towering hydrothermal chimneys discovered on seafloor off Washington

Base of “black smoker” chimney, Pacific Ocean [image credit: USGS]

How many more such discoveries could be waiting to be made? The report says ‘Geologic evidence…suggests that hydrothermal activity is part of a cycle that reshapes the seafloor over many thousands of years’.

An autonomous diving robot captured the vents in unprecedented detail, reports Live Science.

In the dark ocean depths off the coast of the Pacific Northwest, a magical fairyland of towering spires and hydrothermal chimneys sprout from the seafloor, a stunning new underwater map reveals.

These towers belch superheated liquid warmed by magma deep inside Earth.

The field of hydrothermal chimneys stretches along the ocean bottom on the Juan de Fuca Ridge to the northwest of coastal Washington state, in an area known as the Endeavor Segment.

Research reveals possibly active tectonic system on the Moon

Image credit: naturalnavigator.com

We’re told: ‘They refer to what they’ve found as ANTS, for Active Nearside Tectonic System’, which is ‘a mysterious system of tectonic features (ridges and faults) on the lunar nearside, unrelated to both lava-filled basins and other young faults that crisscross the highlands.’ Tectonic activity on one side only sounds a bit unlikely somehow, but what about tidal disturbance from Earth? We know it works the other way round: the Moon causes tides on Earth. Of course the Moon is tidally locked to Earth, hence the term ‘nearside’.
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Researchers have discovered a system of ridges spread across the nearside of the Moon topped with freshly exposed boulders, reports Phys.org.

The ridges could be evidence of active lunar tectonic processes, the researchers say, possibly the echo of a long-ago impact that nearly tore the Moon apart.

“There’s this assumption that the Moon is long dead, but we keep finding that that’s not the case,” said Peter Schultz, a professor in Brown University’s Department of Earth, Environmental and Planetary Sciences and co-author of the research, which is published in the journal Geology.

“From this paper it appears that the Moon may still be creaking and cracking—potentially in the present day—and we can see the evidence on these ridges.”

New geochemical tool reveals origin of Earth’s nitrogen: Novel analysis method may also be useful for monitoring volcanic activity

As the video reminds us: Earth’s atmosphere is mostly (78%) nitrogen. Plus about 21% oxygen at sea level, and a few minor trace gases – one or two of which some people like to fixate on.

Researchers have used a new geochemical tool to shed light on the origin of nitrogen and other volatile elements on Earth, which may also prove useful as a way to monitor the activity of volcanoes, says ScienceDaily.

Their findings were published April 16, 2020, in the journal Nature.

Nitrogen is the most abundant gas in the atmosphere, and is the primary component of the air we breathe. Nitrogen is also found in rocks, including those tucked deep within the planet’s interior.

Until now, it was difficult to distinguish between nitrogen sources coming from air and those coming from inside the Earth’s mantle when measuring gases from volcanoes.

Ear-pleasing new report confirms volcanic source of mysterious global hum

Credit: metro.co.uk

The idea is that “Every time the rock sags into the chamber, it creates a resonance and this produces this strange signal that you see far away.” Is this really ‘The Hum’?

Can you hear it? That elemental thrumming emerging just beneath the engulfing din of everyday city and suburban life? 

Well, chances are you’re not losing your mind or developing some extra-human ability akin to comic book superheroes, says SyfyWire.

Better odds are that it’s Mother Earth’s growing pains in the form of loud volcanic stirrings, as revealed in a new study published in the journal Nature Geoscience.

Forces from Earth’s spin may spark earthquakes and volcanic eruptions at Mount Etna

Mount Etna, Sicily

The article says: ‘Every 6.4 years, the axes line up and the wobble fades for a short time.’ This looks a lot like 5.4 Chandler wobbles (CW), so you would have 6.4 years minus 5.4 CW = 1 cycle, i.e. 32:27 ratio = 5 (32-27) cycles.
Much more analysis of this time period and related matters in this 2013 Talkshop post:
Ian Wilson: Solar System Timings Evolved Lunar Orbital Elements Linked to Earth’s Chandler Wobble.

New research suggests forces pulling on Earth’s surface as the planet spins may trigger earthquakes and eruptions at volcanoes, reports Phys.org.

Seismic activity and bursts of magma near Italy’s Mount Etna increased when Earth’s rotational axis was furthest from its geographic axis, according to a new study comparing changes in Earth’s rotation to activity at the well-known Italian volcano.

Six hot rocky exoplanets orbiting very close to their stars could shed light on the geology of planets in our solar system

A researcher said of one of the new finds: “It is hard to see how the planet got there!”
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Six ‘very hot’ rocky exoplanets orbiting stars in the local region of the Milky Way hold the key to understanding more about how the Earth was formed, astronomers claim.

Researchers from the Open University have been studying planets discovered by the European Space Observatory’s planet-hunting telescope in Chile.

They are orbiting stars between 160 and 440 light years from Earth and all have hot surfaces with temperatures of around 2,012F to 3,272F.

The new findings could shed light on the geology of Earth and other rocky planets in the Solar System including Mercury, Venus and Mars, researchers say.

Full Daily Mail report here.

Geochemists measure new composition of Earth’s mantle

The grand cliffs of the island of São Jorge, formed by fissural volcanism. [Credit: Azores @ Wikipedia]

New research suggests that ‘the composition of Earth’s entire mantle may differ from current thinking’. More work for theorists beckons.

What is the chemical composition of the Earth’s interior?

Because it is impossible to drill more than about ten kilometres deep into the Earth, volcanic rocks formed by melting Earth’s deep interior often provide such information, says Phys.org.

Geochemists at the Universities of Münster (Germany) and Amsterdam (Netherlands) have investigated the volcanic rocks that build up the Portuguese island group of the Azores.

Their goal: gather new information about the compositional evolution of the Earth’s mantle, which is the layer roughly between 30 and 2,900 kilometres deep inside the Earth.

Origin of massive methane reservoir identified

Natural gas flare {credit: Wikipedia]

As we already knew from elsewhere in the solar system, fossils are not essential for the production of methane aka natural gas. Only two ingredients are needed, one being water, as explained below.

New research from Woods Hole Oceanographic Institution (WHOI) published Aug. 19, 2019, in the Proceedings of the National Academy of Science provides evidence of the formation and abundance of abiotic methane—methane formed by chemical reactions that don’t involve organic matter—on Earth and shows how the gases could have a similar origin on other planets and moons, even those no longer home to liquid water.

Researchers had long noticed methane released from deep-sea vents, says Phys.org. But while the gas is plentiful in the atmosphere where it’s produced by living things, the source of methane at the seafloor was a mystery.

Site of biggest ever meteorite collision in the UK discovered

Hebridean islands of Scotland

So it is believed at least. Researchers say a more detailed underwater survey is needed.

Evidence for the ancient, 1.2 billion years old, meteorite strike, was first discovered in 2008 near Ullapool, NW Scotland by scientists from Oxford and Aberdeen Universities.

The thickness and extent of the debris deposit they found suggested the impact crater—made by a meteorite estimated at 1km wide—was close to the coast, but its precise location remained a mystery.

In a paper published today in Journal of the Geological Society, a team led by Dr. Ken Amor from the Department of Earth Sciences at Oxford University, show how they have identified the crater location 15-20km west of a remote part of the Scottish coastline.

California’s current earthquake hiatus is an unlikely pause

1989 Loma Prieta earthquake damage [image credit: H.G. Wilshire, U.S. Geological Survey]

Smaller quakes seem to have taken over, for the time being at least. The Loma Prieta earthquake of 1989 in Northern California had a magnitude of 6.9 but was not considered to be ‘major’, despite some deaths and billions of dollars worth of damage.

There have been no major ground rupturing earthquakes along California’s three highest slip rate faults in the past 100 years, reports ScienceDaily.

A new study concludes that this current ‘hiatus’ has no precedent in the past 1000 years.

U.S. Geological Survey researchers Glenn Biasi and Kate Scharer analyzed long paleoseismic records from the San Andreas, San Jacinto and Hayward Faults for the past 1000 years, to determine how likely it might be to have a 100-year gap in earthquakes across the three faults.

They found that the gap was very unlikely — along the lines of a 0.3% chance of occurring, given the seismic record of the past 1000 years.

South Korea accepts geothermal plant probably caused destructive quake

National flag of South Korea

Is this the end for ‘enhanced’ geothermal technology? Note this quake was 1,000 times stronger than the next one of similar causes.

The nation’s energy ministry expressed ‘deep regret’, and said it would dismantle the experimental plant, as Nature News reports.

A South Korean government panel has concluded that a magnitude-5.4 earthquake that struck the city of Pohang on 15 November 2017 was probably caused by an experimental geothermal power plant.

The panel was convened under presidential orders and released its findings on 20 March.

What can machine learning reveal about the solid Earth?

The ability to recognize patterns in Earth’s behaviour by sifting through masses of geological data could be programmed into machines.

Scientists seeking to understand Earth’s inner clockwork have deployed armies of sensors listening for signs of slips, rumbles, exhales and other disturbances emanating from the planet’s deepest faults to its tallest volcanoes.

“We measure the motion of the ground continuously, typically collecting 100 samples per second at hundreds to thousands of instruments,” said Stanford geophysicist Gregory Beroza. “It’s just a huge flux of data.”

Yet scientists’ ability to extract meaning from this information has not kept pace, reports Phys.org.