Quote:Storm blows a 200ft hole in Guatemala City, swallowing a building
By Mail Foreign Service

Last updated at 11:52 AM on 2nd June 2010

The enormous crater appeared in the Central American country's capital, Guatemala City, as it was being ravaged by torrential rain and mudslides during Tropical Storm Agatha.

Agatha, the first named storm of the 2010 Pacific season, slammed into Guatemala and neighbouring El Salvador at the weekend, dumping more than three feet of rain in the region.

The enormous crater appeared while the city was being ravaged with high winds, torrential rain and deadly mudslides. Witnesses claim at least one man was in the three-storey building when it was swallowed up at a downtown intersection, and others remain missing.

Sink hole: This incredible picture shows a 200ft-deep hole in an intersection in downtown Guatemala City. In the top left of the intersection stood a three-storey building

Agatha has killed at least 146 people across Central America, and has sparked fears for the economies of Guatemala and El Salvador - as there has been widespread damage to the coffee crop in both countries.
'I've got no one to help me. I watched the water take everything,' said Carlota Ramos in the town of Amatitlan near the Guatemalan capital, crying into her hands outside her brick house almost completely swamped by mud.
As the sun came out, exhausted rescue workers hauled away stones and tree trunks from crushed houses as they fought to reach wounded people and find dozens still missing.

'We just have shovels and picks. We don't have any machinery to dig,' said firefighter Mario Cruz, who had been working almost nonstop since Friday night.

Lucky escape: Neighbouring buildings are left untouched after torrential rain led to this huge crater forming in the capital. The area has been closed off and evacuated

At least 123 people have died in Guatemala, and 59 others are missing, according to the government. Nine people were killed in El Salvador and 14 in Honduras, including a woman who was electrocuted as she was helped from her flooded home.

Helicopters ferried tents and medical supplies to remote towns on Guatemala's Pacific coast and the first foreign aid began to flow in on Monday.

The U.S. government donated $113,000 to pay for emergency supplies and to charter private helicopters to assist in the relief effort. The Guatemalan government is expected to formally appeal for aid today.

More than 94,000 people have been evacuated from the capital.
Sink holes can appear suddenly but are thousands of years in the making, geologists said.

The gaping holes are usually caused by rainwater gradually eating away at porous rock such as limestone below the surface, weakening it, and creating a honeycomb of caverns and caves which can become packed with mud. Floodwater may have flushed away that mud - leading everything above it to collapse.

Ash threat: Officials blame mudslides and sink holes in the capital on poor drainage, due to ash from the Pacaya volcano blocking drains. The volcano erupted last week, laying a blanket of ash on everything - including the runway at Guatemala City's international airport

The coffee crop in Guatemala and El Salvador is now at risk from a destructive fungus in the wake of the storm, but mudslides and collapsed bridges have made it hard to assess the damage.

Guatemalan officials have warned the flooding from Agatha could be worsened by ash from the Pacaya volcano blocking drains.

Last Thursday's eruption forced the closure of Guatemala City's international airport. Ash again covered the tarmac yesterday, delaying plans to reopen the facility, aviation officials said.

Read more: http://www.dailymail.co.uk/news/worldnews/article-1283066/Guatemala-sink-hole-Tropical-storm-Agatha-blows-200ft-hole-city.html#ixzz0rIWXAn3d

Quote:Giant sinkholes appear across China

Dozens of sinkholes have emerged across in China in recent weeks, triggering fears of earthquakes.

Craters of different sizes have been seen in a vast area of land stretching across eastern and southern China's Jiangxi, Zhejiang, Sichuan, Hunan, Jiangsu and Guangxi province, state media reported.

In Ningxiang county in central Hunan Province, the toilet of a farmer's home collapsed, but nobody was injured, official Xinhua news agency reported.

Days earlier, a giant sinkhole swallowed up the entire playground of a primary school in the county.

Another hole with an 80m diameter opened up in the same county recently and families living nearby were soon evacuated from the dangerous areas.

Cheng Jie, a geological expert from the China University of Geoscience, said: "I think it is very unlikely that the sinkholes were caused by human activities. It is mainly a result of natural causes, like the sharp weather changes from extreme droughts to heavy rainstorms."

Magda Hassan Wrote:I nearly posted about the Guatemalan sinkhole when I saw it in the news a couple of weeks ago as it looked so symmetrical and photoshop like. There was also another sinkhole in Guatemala just a few years before. Also very, very deep. I had no idea that this had been happening in China in multiple locations.

Quote:Don't Call The Guatemala Sinkhole a Sinkhole

Analysis by Michael Reilly
Wed Jun 2, 2010 09:34 PM ET

The giant sinkhole that opened beneath downtown Guatemala City over the weekend is all the rage right now. There's just one problem: it isn't a sinkhole.

"Sure, it looks a lot like a sinkhole," geologist Sam Bonis told Discovery News from his home in Guatemala. "And a whale looks a lot like a fish, but calling it one would be very misleading."

Instead, Bonis prefers the term "piping feature" -- a decidedly less sexy label for the 100-foot deep, 66-foot wide circular chasm. But it's an important distinction, he maintains, because "sinkholes" refer to areas where bedrock is solid but has been eaten away by groundwater, forming a geological Swiss cheese whose contours are nearly impossible to predict.

The situation beneath the country's capital is far different, and more dangerous.

The lion's share of the city is built on pumice fill -- ash flows made up of loose, gravel-like particles deposited during ancient volcanic eruptions. In places, the debris is piled over 600 feet thick, filling up what would otherwise be a v-shaped valley of faulted bedrock. For those peering into the deep dark depths wondering what might be at the bottom, it's either more pumice fill or bedrock. Mixed with a healthy dose of wreckage from the swallowed-up clothing factory.


WATCH VIDEO: Hurricanes, volcanic eruptions, flash floods: See how scientists are studying natural disasters. In 2007, a similar hole opened after a sewage pipe broke pipe just a few blocks from this weekend's disaster. Bonis was part of a team of geologists and engineers brought in to investigate and advise officials on what went wrong.

"Our recommendation was that this could happen again," he recalled. "When you have water flowing from storm water runoff, a sewage pipe, or any kind of strong flow, it eats away at the loose material. We don't know how long it has to go on before it collapses. But once it starts collapsing, God help us."

The Guatemala City metro area is home to nearly 3 million people. Not all of them live on the fill -- Bonis estimates around 1-1.5 million, with the rest perched on the valley walls -- but by mislabeling the feature a sinkhole, it distracts from a dangerous situation that could be mitigated, if not neutralized, by better handling of the city's runoff and waste water.

"I'd hate to have to be in the government right now," Bonis, who worked for the Guatemalan government's Instituto Geografico Nacional for sixteen years, said. "There is an excellent potential for this to happen again. It could happen almost anywhere in the city."

Quote:
Mined out kimberlite pipe, Kimberley Big Hole, Kimberley, South Africa.
Note the crater wall which is natural and formed by a “vortex” mechanism of unknown origin.

The Electrical Origin of Kimberlite Pipes
Jan 25, 2010

One of the more perplexing mysteries in geology is the mechanism behind kimberlite eruption at the Earth’s surface, because these eruptions have never been witnessed.

Historically, kimberlite eruptions tend to occur on the tectonically stable parts of the Earth’s landmasses, well away from the tectonically active zones where many active volcanoes are found, and from the stability of diamond-graphite pair we know they erupt catastrophically over a very short time, taking a matter of half a day from the initial melting in the mantle to eruption and solidification at the surface.

Another peculiarity these ancient volcanoes have lies in the close chronological association with global mass extinction events, where the globally largest eruptions of these rocks occurred at the Cretaceous extinction event.

The actual process which formed the kimberlite crater or diatreme remains unknown, because there is clear evidence that these diatremes were machined downwards from the surface by a magmatic vortex effect. The final puzzle lies in the origin of these rather unique rocks—some 220 kilometers under the surface, well away from active tectonic zones.

What could have affected the upper mantle at those depths to allow partial melting and the rapid ascent of the, occasionally diamond bearing, kimberlite magma to the earth’s surface?

The New Concepts in Global Tectonics Newsletter issue No 43 of June 2007, published an important paper by the Russian scientist Konstantin K. Khazanovitch-Wulf who proposed that kimberlites and related rocks are linked to disruptions in the Earth’s electric field caused by the electromagnetic effect of a passing cosmic body or meteorite. Earlier research by Russian scientists also point to earthquakes being caused by subterranean electric discharges, and which could also trigger kimberlite eruptions. In his model it is the actual physical disruption of the earth’s electrical field by the electrically active interloper that initiated the kimberlite eruptions, and presumably also the associated mass species extinctions.

This strongly suggests kimberlite eruptions are essentially electrical discharge sites of short duration between the Earth and another cosmic body, where electrical charge differences between the Earth and the interloper caused electrical short circuits between them. The rotary or tunneling mechanism recognized from the shape and structure of the kimberlite diatremes can then be explained as the result of powerful Birkeland currents corkscrewing into the Earth’s surface forming the smooth and steep sides of the kimberlite diatreme.

Geological mysteries disappear when the Plasma Model is used to explain observed facts.

Contributed by Louis Hissink

Louis Hissink, M.Sc., is a consulting geologist in Perth, Western Australia. He is a Member of the Australian Institute of Geoscientists and editor of the A.I.G. News.

Quote:Kimberlite pipes carved by electromagnetic forces

23 Jun 10 - Although kimberlite eruptions at the Earth’s surface have never been witnessed, we know they erupt catastrophically over a very short time, taking half-a-day from the initial melting in the mantle to eruption and solidification at the surface, says this article on thunderbolts.com.


Mined out kimberlite pipe, Kimberley Big Hole, Kimberley,
South Africa. Note the crater wall is natural and formed by
a “vortex” mechanism of unknown origin.

There is clear evidence that these diatremes were machined downward from the surface by a magmatic vortex effect, the article continues, and that these ancient volcanoes lie in close chronological association with mass extinctions. The largest eruptions occurred at the end-Cretaceous (the dinosaur extinction).

"What could have affected the upper mantle at those depths to allow partial melting and the rapid ascent of the, occasionally diamond bearing, kimberlite magma to the earth’s surface?" the article asks.

"Kimberlites are linked to disruptions in the Earth’s electric field caused by the electromagnetic effect of a passing cosmic body or meteorite," the article explains. Earlier research also shows subterranean electric discharges may trigger earthquakes, which could also lead to kimberlite eruptions.

"This strongly suggests kimberlite eruptions are essentially electrical discharge sites of short duration between the Earth and another cosmic body, where electrical charge differences between the Earth and the interloper caused electrical short circuits between them."

"The rotary or tunneling mechanism recognized from the shape and structure of the kimberlite diatremes can then be explained as the result of powerful Birkeland currents corkscrewing into the Earth’s surface forming the smooth and steep sides of the kimberlite diatreme."

I'm willing to keep an open mind here. However, I'm more
inclined to suspect that a magnetic reversal was involved,
and that the electrical discharge came all the way from
another planet. I'd be curious to learn if there was indeed
a magnetic reversal at the time.

See:
http://www.thunderbolts.info/tpod/2010/arch10/100125kimberlite.htm
Thanks to Stephanie Relfe for this link.

Quote:What causes sinkholes?

It's the stuff of nightmares: last week, the ground opened up and swallowed a Florida man as he lay sleeping in his home. But why do these sinkholes occur and how widespread are they?

Jon Henley
The Guardian, Monday 4 March 2013 17.35 GMT
Jump to comments (24)

Link to video: Sinkhole house in Florida demolished

Last week, in a quiet residential suburb east of Tampa, Florida, the Earth opened up and swallowed a man. Jeff Bush, 37, was tucked up in bed late on Thursday evening when his entire bedroom floor simply gave way with a deafening crash that his brother, in the room next door, later described as "like a truck hitting the house".

Jeremy Bush, 35, heard his brother's scream and rushed towards his bedroom. "Everything was gone," he told local television stations. "My brother's bed, my brother's dresser, my brother's TV. My brother was gone. All I could see was the top of his bed, so I jumped in and tried digging him out. I thought I could hear him screaming for me and hollering for me."

As the house's floor threatened to collapse further into a gaping hole more than 9m across and 15m deep, a sheriff's deputy who had arrived on the scene with the emergency services eventually pulled Jeremy to safety. Jeff remained trapped. "I couldn't get him out," Jeremy said. "I tried so hard. I tried everything I could. No one could do anything."

As Jeremy and four others, including a two-year-old child, were led away uninjured, rescue teams lowered a microphone and video camera into the hole, but it was soon apparent that Bush could not have survived. By Saturday, the search for his body had also been abandoned. "We just have not been able to locate Mr Bush, and so for that reason, the rescue effort is being discontinued," a local official, Mike Merrill, said. "At this point, it's really not possible to recover the body."

When the ground begins opening up beneath our feet and plunging unsuspecting mortals into the abyss, some may be tempted to reach for the Bible and start predicting the End of Times (and a quick online search reveals that several of the wackier sort of website have not hesitated to do just that). But biblical as the story sounds, the sinkhole as the phenomenon is called that caused Jeff Bush's death was not an act of God but of geology.
A sinkhole in Guatemala City A sinkhole in the centre of Guatemala City that swallowed a three-storey building in May 2010. Photograph: Luis Echeverria/AP

Natural sinkholes as opposed to manmade tunnel or cave collapses occur when acidic rainwater seeps down through surface soil and sediment, eventually reaching a soluble bedrock such as sandstone, chalk, salt or gypsum, or (most commonly) a carbonate rock such as limestone beneath. In a process that can last hundreds, sometimes thousands of years, the water gradually dissolves small parts of the rock, enlarging its natural fissures and joints and creating cavities beneath.

As the process continues, the loose, unconsolidated soil and sand above is gradually washed into these cracks and voids. Depending on how thick and strong that top layer is (sand will not last long; clay can hold out for millennia), and how close to the surface the void beneath is, the land may be able to sustain its own weight and that of whatever we build on top of it. But as the holes grow, there will come a day when the surface layer will simply give way.

"Once those caves start to collapse, the materials above will simply funnel in," says Dr Anthony Cooper, a principal geologist at the British Geological Survey, which maps the country for rock types susceptible to sinkholes and carries out surveys for developers, builders and individuals worried about the prospects of the land caving in beneath them. "It's just like an eggtimer, really. That's certainly what appears to have happened with this incident in Florida."
Jeremy Bush, Seffner, Florida Jeremy Bush, right, is consoled as he sits outside the home where a sinkhole swallowed his brother Jeffrey Bush. The house has since been demolished. Photograph: Chris O'Meara/AP

In the language of geologists, the process that causes sinkholes is "the creation of a void which migrates towards the surface". In the language of the layman, when there's not enough solid stuff left underneath to support what is left of the loose stuff above, the whole lot collapses. The resulting depressions characterise what is known as a karst landscape, in which hundreds or even thousands of relatively small sinkholes form across an area that, seen from the air, can appear almost pock-marked.

Since around 10% of the world's surface is made up of karst topographies, sinkholes are far from uncommon. The entire state of Florida, as the Bush family unfortunately learned, is classed as karst landscape, and sinkholes are so common that insurers are obliged by law to offer cover to home owners who ask for it (insurance was compulsory until 2007, when many home owners dropped it because of the rising cost). "If you look at a satellite image of the state, or even just a map," says Cooper, "you'll see it's peppered with little circular lakes and lots and lots of sinkholes. A great many of them are visible, but many more are covered in. It's typical karst topography."

Elsewhere in the US, sinkholes are common in Texas, Alabama, Missouri, Kentucky, Tennessee and Pennsylvania. In Britain, the BGS says the carboniferous limestone of the Mendip Hills, the north of the South Wales coalfield, the Peak District, the Yorkshire Dales, the northern Pennines and the edges of the Lake District all host well-developed karst landscapes. Karstic features are also common in the UK on the chalk of south-east England, on salt in the centre and north-east of the country, and particularly on the gypsum that underlies parts of eastern and north-eastern England, especially around Ripon and Darlington, and in the Vale of Eden.

"Gypsum is the most soluble of all," says Cooper. "If you were to place a block of gypsum the size of a transit van in a river, it would dissolve completely within about 18 months." Ripon in North Yorkshire, Cooper says, is very susceptible to sinkholes, the most famous some 20m deep dating back to 1834. In 1997, four garages collapsed into a huge sinkhole that only just missed the front of a neighbouring house.

One of the more spectacular recent British sinkholes, a 7.5m-deep crater, opened up in 2010 beneath a patio in Grays, Essex. "It was like an earthquake. There was a rumbling and we both ran out to look and there just a couple of steps away there was this monstrous hole," the house owner, Ben Luck, said at the time. "It was there in a second. There wasn't a bit of dust, and there was no sign of the crazy paving it had all disappeared in the hole." Structural engineers said the hole was caused after water penetrated chalk some 25m down, causing tonnes of soil above it to shift.
Sinkhole in house This sinkhole appeared overnight in a house in Guatemala City in 2011. It was 12.2m deep and 80cm in diameter. Photograph: Johan Ordonez/AFP

Around the world, this process that produces sinkholes has created such striking natural features as the hills of Ireland's western coast, the caves of Slovenia and the pillars of Guilin in China. Where the underlying limestone layer is thick and rainfall heavy, vast underground caverns and subterranean rivers have produced sinkholes of dimensions that make what's happened in Florida or Essex look positively insignificant: the Xiaozhai tiankeng ("heavenly pit") in Chongqing, China, is 662m deep; the Dashiwei tiankeng in Guangxi 613m. Croatia has a 530m-deep hole, with vertical walls, called the Red Lake, while Papua New Guinea has the Minyé sinkhole (510m deep) and Mexico the Sótano del Barro (410m) and Sótano de las Golondrinas (372m deep).

What finally triggers a collapse? The most common factor, Cooper says, is changing groundwater levels, or a sudden increase in surface water. During long periods of drought, groundwater levels will fall, meaning cavities that were once supported by the water they were filled with may become weaker (water pumping, for factories or farms, can have a similar effect). Conversely, a sudden heavy downfall can add dramatically to the weight of the surface layer of soil and clay, making it too heavy for the cave beneath to bear.

Link to video: Huge sinkhole in Guangzhou swallows buildings

Sometimes the trigger can be man-made. In chalky West Sussex in 1985, a burst water main caused an alarming rash of small 1m- to 4m-wide sinkholes to appear in Fontwell. "There was also a man who emptied his swimming pool out on to his garden, and was soon confronted with a large sinkhole under his house," Cooper says. "And in Florida, automatic frost sensors have set off sprays fed from boreholes and intended to stop strawberry crops from freezing but the result was more than 100 small sinkholes."

So how can you detect a developing sinkhole and can anything be done about it once you suspect the process may be under way? In Britain, Cooper says, the BGS maps the country to locate rock types that may be affected by sinkholes. It also keeps an up-to-date National Karst Database recording visible sinkholes, springs, soakaways and known building damage. Using all manner of modern technologies, "we cut an awful lot of data, from rock types to slope angles, covering materials and drainage, and basically zone the country into datasets that can be used by property developers, local councils, the construction industry, insurers and the like," he says.

At the most basic level, people in a sinkhole-prone zone are best advised simply to "look around them, at the adjacent land and buildings". Telltale signs may include sagging trees or fence posts, doors or windows that no longer close properly, and rainwater collecting in unlikely places. Some developing sinkholes can be filled in; Anthony Randazzo, a former University of Florida professor who has spent his career studying sinkholes, now runs a profitable company that does just that, injecting grout to fill cracks that develop underground and shore up the foundations of buildings. "It's like a dentist filling a cavity," he says.

But this is not always possible. The key is good drainage; you want to get water away from a vulnerable area. "Covering an opening up with concrete, or filling up a hole completely with solid concrete, may not necessarily help," warns Cooper. Sometimes, too, the hole may simply be too deep: 80m, perhaps, compared with the 12-15m height of a house. "On some occasions, we have had to point out to developers that a hole 20m deep and 30m wide is a lot bigger than a house," Cooper says. "That's a hell of a lot of concrete."

Despite the frequency of sinkholes, linked fatalities are rare. Randazzo says he can recall only two other people besides Bush who have died because of them in the US during the past 40 years. Even then, he says, in both cases the people concerned had been drilling boreholes (and thus interfering with groundwater levels). "Usually, you have some time," Randazzo, who has lectured on sinkholes at Oxford University, told USA Today. "These catastrophic sinkholes give you some warning over the course of hours. This latest incident is very unusual, and very tragic."

In the UK, Cooper says, no deaths attributable solely to naturally formed sinkholes (as opposed, say, to the collapse of disused mine chambers) have been recorded in recent times. But, he points out, since extremes of sinkhole-affecting weather long periods of drought, for example, followed by spells of unusually heavy and persistent rain are widely predicted to become more frequent as the Earth's climate changes, "we would certainly expect there to be more sinkholes in the future". It could be only a matter of time before Britain buries a Jeff Bush.