Monday, May 31, 2010

Guatemala Sinkhole

Guatemala Sinkhole appears, the said cause for the sinkhole was the overwhelming tropical storm Agatha. Here is a photo that had been posted by the Guatemalan Government showing the “hundimiento” – a spontaneous sinkhole. According to scientists, this occurrence happens from time to time when major storms come. It is due to the unstable geology. This happened just yesterday, May 31,2010. The picture is not edited and sadly it is real. According to the news, more than a hundred people died due to the intense weather. Some sources said that a security guard was kiled by the crater as it was opening widely. The opening of the crater was said to be rare for this kind of a natural depression. The normal process would entail the crater to open slowly and not what had happened where the Guatemala sinkhole suddenly opened. A sinkhole is a natural depression or hole in the surface topography caused by the removal of soil and or bedrock caused by water.



Guatemalan President Alvaro Colom said last Sunday during the Nation Address that there were nearly 112,000 have been evacuatedand 29,000 are living at temporary shelters. The Pacaya Volcano eruption distressed Guatemala greatly and was further extensified by the tropical storm Agatha and later on the Guatemala Sinkhole. Reports say that there were at least 92 deaths, 54 missing and 59 injured.

This is a very devastating moment for the people who live there. We hope and pray that everyone will recover from this tragedy.

Sinkholes are a natural gorge on the outer layer or crust of the earth. These are cause when the soil is removed and/or base by water. They may as well diverge in range as well as depth, from below a meter up to numerous hundred meters. Their construction has also a wide deviation, from soil-lined bowls to bedrock-edged fissures. Sinkholes are discovered in different part of the world that may develop slowly or unexpectedly.

In the case in Guatemala, the hole crack opens abruptly. A sinkhole like the current giant sinkhole in Guatemela as well appeared a couple of years ago near the territory. While the speculation regarding the faulty underground sewage drainage system might prove to be real in the current case, it may not be the solely rationality. It may as well have something to do with the type as well as humidity level of the soil that this place has. In addition, the amount of weight on top of the deep section of the ground may have as well stimulated the formation of this giant sinkhole.



The storm battered Guatemala along with the other cities of Central America a couple of days ago and brought tremendous flood of water. It stopped on Sunday, however, left numerous of destroyed houses and killed more or less than a hundred individuals.

Sinkholes have also appeared in several places like in Florida. Most of the time they are slight holes, nevertheless, this extremely giant sinkhole appears to be exceedingly deep.

A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or cenote, is a natural depression or hole in the surface topography caused by the removal of soil or bedrock, often both, by water. Sinkholes may vary in size from less than a metre to several hundred metres both in diameter and depth, and vary in form from soil-lined bowls to bedrock-edged chasms. They may be formed gradually or suddenly, and are found worldwide. These terms are often used interchangeably though many will distinguish between those features into which a surface stream flows and those which have no such input. Only the former would be described as sinks, swallow holes or swallets. A sinkhole on a glacier is termed a moulin or glacier mill.

Occurrence

Sinkholes may capture surface drainage for running or standing water, but may also form in currently high and dry locations. The state of Florida in the USA is known for having frequent sinkholes, especially in the central part of the state. The Murge area in southern Italy also has numerous sinkholes. Sinkholes can be formed in retention ponds from large amounts of rain.

Sinkholes are usually but not always linked with karst landscapes. In such regions, there may be hundreds or even thousands of sinkholes in a small area so that the surface as seen from the air looks pock-marked, and there are no surface streams because all drainage occurs sub-surface.
Sinkholes have been used for centuries as disposal sites for various forms of waste. A consequence of this is the pollution of groundwater resources, with serious health implications in such areas. In contrast, the Maya civilization sometimes used sinkholes in the Yucatán Peninsula (known as cenotes) as places to deposit precious items and sacrifices.



Sinkholes also form from human activity, such as the rare but still occasional collapse of abandoned mines in places like West Virginia, USA. More commonly, sinkholes occur in urban areas due to water main breaks or sewer collapses when old pipes give way. They can also occur from the overpumping and extraction of groundwater and subsurface fluids.

Many sinkholes are found in Northern Michigan. These are prominent in Alpena County in Northeast Michigan. In Lachine, Michigan there are five sinkholes that are found to be very deep , and within two miles of each other. Alpena's visitor information cites their sinkholes as an attraction for visitors to the area. In August 1998 a 16 year old Alpena boy survived a 200+ ft fall in an open sinkhole 3/4 a mile off of Leer road in Lachine, Michigan (The Alpena News 8-21-1998). A majority of sinkholes in Alpena are also found underwater. Many divers explore these on a regular basis.



When sinkholes are very deep or connected to caves, they may offer challenges for experienced cavers or, when water-filled, divers. Some of the most spectacular are the Zacatón cenote in Mexico (the world's deepest water-filled sinkhole), the Boesmansgat sinkhole in South Africa, Sarisariñama tepuy in Venezuela, and in the town of Mount Gambier, South Australia. Sinkholes that form in coral reefs and islands that collapse to enormous depths are known as Blue Holes, and often become popular diving spots.
In the United States, the most damage from sinkholes tends to occur in Florida, Texas, Alabama, Missouri, Kentucky, Tennessee, and Pennsylvania. Palmyra, Pennsylvania is the sinkhole capital of America.

The overburden sediments that cover buried cavities in the aquifer systems are delicately balanced by groundwater fluid pressure. The water below ground is actually helping to keep the surface soil in place. Groundwater pumping for urban water supply and for irrigation can produce new sinkholes in sinkhole-prone areas. If pumping results in a lowering of groundwater levels, then underground structural failure, and thus, sinkholes, can occur.