Diasaster Ahead: Earthquakes and Volcanos

Two factors suggest that something is deeply wrong on the surface of the earth’s crust: earthquakes and volcanos. Why? I’ve been studying some of the reports on Volcanic activity around the world, along with the sudden rise in earthquake activity as well in the past year. In the past 48 hours the earth has suddenly produced 5 major earthquakes along with Volcanos that are erupting all over the planet. USGS shows the largest recent earthquake in Ecuador at 7.8. Another report shows 40 volcanoes erupting around the planet at the moment.

According to the Guardian the gravitational pull of the sun and moon, the speed at which the Earth rotates constantly changes, is affecting us more than usual. Accordingly the length of a day actually varies from year to year. The difference is only in the order of milliseconds. But new research suggests that this seemingly small perturbation could bring about significant changes on our planet – or more accurately, within it.

A study published in the journal Terra Nova in February showed that, since the early 19th century, changes in the Earth’s rotation rate tended to be followed by increases in global volcanic activity. It found that, between 1830 and 2013, the longest period for which a reliable record was available, relatively large changes in rotation rate were immediately followed by an increase in the number of large volcanic eruptions. And, more than merely being correlated, the authors believe that the rotation changes might actually have triggered these large eruptions.

Altering the spin of a planet, even by a small amount, requires a huge amount of energy. It has been estimated that changes in the Earth’s rotation rate dissipate around 120,000 petajoules of energy each year – enough to power the United States for the same length of time.

This energy is transferred into the Earth’s atmosphere and subsurface. And it is this second consequence that the Terra Nova authors believe could affect volcanoes.

The vast quantities of energy delivered to the subsurface by rotation changes are likely to perturb its stress field. And, since the magma that feeds volcanic eruptions resides in the Earth’s crust, stress variations there may make it easier for the liquid rock to rise to the surface, and thereby increase the rate of volcanic eruptions.

The Terra Nova study is far from conclusive. Nevertheless, the idea that minute changes to the Earth’s spin could affect volcanic motions deep within the planet is intriguing.

Climate Change Impact

There is also the impact of climate change.

Around 19,000 years ago, glaciation was at a peak. Much of Europe and North America was under ice. Then the climate warmed, and the glaciers began to recede. The effect on the planet was generally quite favourable for humankind. But, since the mid-1970s, a number of studies have suggested that, as the ice vanished, volcanic eruptions became much more frequent. A 2009 study, for example, concluded that between 12,000 and 7,000 years ago, the global level of volcanic activity rose by up to six times. Around the same period the rate of volcanic activity in Iceland soared to at least 30 times today’s level.

There is supporting evidence from continental Europe, North America and Antarctica that volcanic activity also increased after earlier deglaciation cycles. Bizarrely, then, volcanic activity seems – at least sometimes – to rise and fall with ice levels. But why? This strange effect might come down to stress.

The link between climate change and volcanism is still poorly understood. Many volcanoes do not seem to have been affected by it. Nor is it a particularly pressing concern today, even though we face an ice-free future. It can take thousands of years after the glaciers melt for volcanic activity to rise.

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 Ecuador Earthquake

Rescue crews searched desperately through rubble for survivors of a magnitude-7.8 earthquake that struck coastal Ecuador.

The tremor was centered 27 kilometers (16.8 miles) southeast of the coastal town of Muisne, according to the U.S. Geological Survey.

It’s the deadliest earthquake to hit the nation since March 1987 when a  7.2-magnitude temblor killed 1,000 people, according to the USGS.

“It was the worst experience of my life,” survivor Jose Meregildo said Sunday about the tremors that violently shook his house in Guayaquil, 300 miles away from the quake’s epicenter. “Everybody in my neighborhood was screaming saying it was going to be the end of the world.”

The earthquake hit Saturday around 7 p.m. while people were going about their evening. The tremors buckled overpasses trapping drivers. A shopping mall partially collapsed on customers and several buildings have been flattened with their content spilled into the streets.

All six coastal provinces — Guayas, Manabi, Santo Domingo, Los Rios, Esmeraldas and Galapagos — are in state of emergencies.

People left their homes and wandered around, some sleeping in the streets.

“I found my house like this,” said Nely Intriago, standing in front of a pile of rubble. “What am I going to do? Cry, that’s what. Now we are on the street with nothing.”

(from CNN report…)

Pacific Northwest

Could a 8.0 or better earthquake hit the Pacific Northwest?  According to Chris Goldfinger: yes, it could, and sooner than you might think. If, on that occasion, only the southern part of the Cascadia subduction zone gives way—your first two fingers, say—the magnitude of the resulting quake will be somewhere between 8.0 and 8.6. Thats the big one. If the entire zone gives way at once, an event that seismologists call a full-margin rupture, the magnitude will be somewhere between 8.7 and 9.2. That’s the very big one. As the article suggests:

Most people in the United States know just one fault line by name: the San Andreas, which runs nearly the length of California and is perpetually rumored to be on the verge of unleashing “the big one.” That rumor is misleading, no matter what the San Andreas ever does. Every fault line has an upper limit to its potency, determined by its length and width, and by how far it can slip. For the San Andreas, one of the most extensively studied and best understood fault lines in the world, that upper limit is roughly an 8.2—a powerful earthquake, but, because the Richter scale is logarithmic, only six per cent as strong as the 2011 event in Japan.

Just north of the San Andreas, however, lies another fault line. Known as the Cascadia subduction zone, it runs for seven hundred miles off the coast of the Pacific Northwest, beginning near Cape Mendocino, California, continuing along Oregon and Washington, and terminating around Vancouver Island, Canada. The “Cascadia” part of its name comes from the Cascade Range, a chain of volcanic mountains that follow the same course a hundred or so miles inland. The “subduction zone” part refers to a region of the planet where one tectonic plate is sliding underneath (subducting) another. Tectonic plates are those slabs of mantle and crust that, in their epochs-long drift, rearrange the earth’s continents and oceans. Most of the time, their movement is slow, harmless, and all but undetectable.

If one hit in this region all chaos would ensue. In the Pacific Northwest, the area of impact will cover everything west of Interstate 5 covers some hundred and forty thousand square miles, including Seattle, Tacoma, Portland, Eugene, Salem (the capital city of Oregon), Olympia (the capital of Washington), and some seven million people. When the next full-margin rupture happens, that region will suffer the worst natural disaster in the history of North America. Roughly three thousand people died in San Francisco’s 1906 earthquake. Almost two thousand died in Hurricane Katrina. Almost three hundred died in Hurricane Sandy. FEMA projects that nearly thirteen thousand people will die in the Cascadia earthquake and tsunami. Another twenty-seven thousand will be injured, and the agency expects that it will need to provide shelter for a million displaced people, and food and water for another two and a half million. “This is one time that I’m hoping all the science is wrong, and it won’t happen for another thousand years,” Murphy says.

(read more… The Big One)

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