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sinkhole
A 30ft deep sinkhole has opened up on the driveway of a house in High Wycombe, UK, and swallowed a car.
Nobody was inside the VW Lupo when the ground on Main Road in Walter’s Ash gave way.
The 30ft deep sinkhole has opened up on the driveway of a house in High Wycombe
The vehicle is still at the bottom covered in rubble.
Firefighters said the hole was about 15ft diameter but left the scene after discovering no-one was inside.
Wycombe District Council will now have to decide what steps to take next.
Ohio driver Pamela Knox had to be rescued from her vehicle after it plunged into a 10-feet deep sinkhole that suddenly appeared in the road.
Pamela Knox didn’t appear hurt but was shaken up by the freak incident. When emergency services arrived she then had to climb out from the hole using a ladder.
The giant hole opened up in a road in Toledo, north west Ohio.
Toledo police Sgt. Joe Heffernan says a water main break beneath the road may have caused the sinkhole on Wednesday.
Sgt. Joe Heffernan says Pamela Knox saw the vehicle in front of her start to slip into the hole but managed to drive beyond it.
Ohio driver Pamela Knox had to be rescued from her vehicle after it plunged into a 10-feet deep sinkhole that suddenly appeared in the road
However, Pamela Knox couldn’t avoid it being swallowed up by it, he said. Once rescued she was taken to a hospital as a precaution
Officials used a crane to pull the car from the hole. Repairs to the road are expected to take days.
Sink holes are caused by the dissolution of soluble bedrock and the frequency and likelihood of such changes occurring depends on a number of natural factors like the type of rock present and the weather conditions in the area.
They often occur after heavy rain and floods, or following earthquakes, and can open up suddenly without any warning.
One of the largest sinkholes in the U.S. is in rural Louisiana, a vast and growing hole which last year was recorded to be 526-feet wide.
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Sinkholes, or dolines, often take thousands of years to form and vary hugely in size.
The deepest is China’s Xiaozhai Tienkeng at 2172 ft (662 m). The Qattara Depression in Egypt is roughly 50 miles (80 km) by 75 miles (121 km) in surface size.
But often sinkholes can be only a few metres in diameter.
They are usually the result of what are known as Karst processes. They happen when a layer of rock underneath the ground is dissolved by acidic water.
Usually this layer is a soluble carbonate rock, such as limestone or its purer form, chalk. Florida is particularly prone to sinkholes as the entire state has limestone underneath it.
Typically rainfall seeps through the soil, absorbing carbon dioxide and reacting with decaying vegetation. As a result, the water that reaches the soluble rock is acidic.
The acidic water causes the erosion of the soluble rock layers beneath the surface – eventually creating cavernous spaces.
The soil or sand over the limestone collapses into a sinkhole when it is no longer supported because of the cavity below. This final collapse of the surface might take anything from a few minutes to several hours.
There are warning signs in urban areas. These include doors and windows failing to close properly, or cracks appearing in the foundations of houses. In some cases ground movement can be detected.
Heavy rainfall or poor drainage systems can trigger a collapse.
But predictions are not easy.
Sinkholes, or dolines, often take thousands of years to form and vary hugely in size
“It can be very difficult to predict collapse because there is very little surface evidence of the features,” says Dr. Vanessa Banks, an expert in shallow geohazards and risk at the British Geological Survey.
Different rock types behave in different ways, she adds.
The timing of a collapse also depends on the nature of the soil or rock at the surface which forms a “bridge” over the growing cavern below.
“Consolidated deposits such as sandstone will bridge voids until their tensional strength is exceeded, when the rock will fail and collapse into the underlying cavity,” says Vanessa Banks.
Certain types of ground – such as gravel and sand – are not fixed in place and so more prone to being washed away.
The erosion may take many years but the collapse may be sudden as it depends on a tipping point determined by the material at the surface, Vanessa Banks says.
Moreover, acidic water varies in its strength – and therefore the rate of erosion – depending on the soil and rock it filters through.
“Water acidity can typically have a pH level of about 6.5 – still drinkable to all intents and purposes – but also be as low as four,” explains Vanessa Banks.
Iron and sand can increase the acidity. So too can sandstone and shale.
Human development can also affect these natural processes.
When people are building a basement, they may need to drain water, explains Vanessa Banks. This drainage of water can destabilize the soil by washing away smaller particles – like sand – that are necessary to keep larger particles together, increasing the chances of collapse.
In January, a sinkhole that swallowed an entire building complex in Guangzhou, China, may have been triggered by the construction of an underground metro line nearby.
Burst water mains or sewage systems also cause many urban sinkholes to happen, regardless of the rock type below.
These cause instability in the surrounding area, often giving the impression of a natural sinkhole, says Vanessa Banks.
Urban development also adds more weight to the surface layer, potentially speeding up the collapse of a sinkhole.
It is crucial to undertake extensive site investigations prior to building work, she says.
Vanessa Banks says that concrete urban development on the whole could in fact be “slowing [sinkholes’ natural] formation by restricting this drainage water from seeping through”.
There are more sinkholes in rural environments, she says, primarily because risky areas are typically avoided by urban developers.
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Demolition crews have partially razed Florida home of Jeffrey Bush, who is presumed dead after he was swallowed up by a sinkhole under his bedroom.
Rescuers earlier ended efforts to find the body of Jeffrey Bush, 36, whose bedroom was engulfed by the 6 m (20 ft) hole on as he slept on Thursday night.
Sinkholes are common in parts of Florida, although most are quite small.
Experts are trying to ascertain how far the underground cavity reaches and whether more homes are at risk.
All homes near to the house in Seffner – a suburb of 8,000 people 25 km (15 miles) east of central Tampa – have been evacuated.
Officials have created a 100ft-wide safety zone fearing the top of the sinkhole is growing.
Jeffrey Bush’s house covers most of the hole, and a local official said crews would try to move the building forward to enable surviving family members to retrieve their belongings from it.
“We don’t know, in fact, whether it will collapse or whether it will hold up,” said Hillsborough County Administrator Mike Merrill.
On Sunday, the demolition crews left standing only a few walls of the house.
They were proceeding as carefully as possible to salvage at least some of the home’s contents for five survivors.
Demolition crews have partially razed Florida home of Jeffrey Bush, who is presumed dead after he was swallowed up by a sinkhole under his bedroom
A Bible, family photos and a woman’s purse were among the items saved.
The demolition is expected to be completed on Monday and experts would then examine the hole.
Just before the crews started their work, 35-year-old Jeremy Bush, who had tried to save his brother, was seen praying outside the house.
Five people escaped unharmed, after hearing a loud crash and Jeffrey Bush screaming as the earth crumbled below the house.
Jeremy Bush said he jumped into the chasm to dig his brother out but failed. He was later rescued by police. .
Rescuers then used listening devices and cameras at the scene, but found no signs of life.
“There’s no way of possible survival,” said fire rescue spokeswoman Jessica Damico on Saturday.
Jeremy Bush told reporters that someone had visited the four-bedroom house some weeks ago to check for sinkholes and other issues but found nothing wrong.
“And a couple of months later, my brother dies. In a sinkhole,” he said.
Florida state law requires home insurers to provide coverage against sinkholes.
Experts say much of Florida sits on a system of limestone caverns which are subject to water erosion, causing them to collapse.
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Jeffrey Bush from Florida has disappeared into a 20 ft-deep (6 m) sinkhole that swallowed up a bedroom in his house.
Jeffrey Bush, 36, is presumed dead after rescue crews failed to make contact with him.
Officials in the town near Tampa have postponed further rescue efforts until they determine how much of the ground under the house is compromised.
Sinkholes are common in certain parts of Florida, Hillsborough County’s fire chief said.
“Florida essentially sits on a system of caverns,” Chief Ron Rogers said, saying water erosion in the caverns causes them to collapse and sinkholes to form on the surface.
The sinkhole is currently 30 ft wide and 20 ft deep, but officials have established a 100 ft-wide safety zone, fearing the top of the sinkhole is growing.
“We don’t know how stable the house is,” Chief Ron Rogers said, adding that additional parts of the home began to collapse into the ground while rescuers were inside.
Jeffrey Bush’s brother Jeremy told rescue crews he heard a loud crash near midnight on Thursday, then his brother screaming for help.
He said he jumped into the hole but couldn’t see his brother.
“The floor was still giving in and the dirt was still going down, but I didn’t care. I wanted to save my brother,” he said, choking back tears outside a neighbor’s house.
“I could swear I heard him hollering my name to help him.”
Jeffrey Bush from Florida has disappeared into a 20 ft-deep sinkhole that swallowed up a bedroom in his house
One of the first responders to the house had to pull Jeremy Bush back from digging through the widening hole.
“All they could see was a part of a mattress sticking out of the hole,” Chief Ron Rogers said.
“Essentially the floor of that room had opened up.”
There has been no contact with Jeffrey Bush since then, although officials said they had inserted cameras and listening kit into the hole.
Neighbors on both sides of the home have been evacuated.
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