Hobbies And Interests
Guatemala City Sinkhole
In 2010, a huge hole opened up in the middle of Guatemala City. Nearly perfectly round with almost vertical sides, the 66-foot wide and 100-foot deep hole is so dramatic some observers say it looks fake. The hole most likely formed because of a combination of aging city architecture eroding the underlying soils, damage from a recent tropical storm, and the unstable volcanic pumice soils underlying the city.
Qattara Depression
The largest sinkhole in the world is the Qattara Depression in Egypt. It runs over 150 miles and at its deepest is almost 450 feet below sea level. It was created when an ancient stream wore away the underlying limestone, creating a huge karstic area, a geological "Swiss cheese" that is prone to collapse in on itself. Karst geology is one of the most common causes of sinkholes around the world, but this one is on a scale that can be seen from space.
Sinkholes in Florida
Many sinkholes that make the news are found in Florida. For example, a sinkhole swallowed part of a block in Winter Park, Florida in 1981. Florida has slightly acidic groundwater that erodes cavities in its limestone bedrock, creating karst formations beneath clay and sand soils. Under stress like a storm that drops a lot of water on the landscape, these formations can collapse. Because these conditions are common across Florida, sinkholes are a frequent occurrence.
The Great Blue Hole
Not all sinkholes are on land. The Great Blue Hole is a sinkhole in the shallow ocean waters off the coast of Belize. This sinkhole formed in the traditional way when a karst limestone formation collapsed, but, at the time, it was above sea level because much of the Earth̵7;s water was tied up in ice age glaciers. The glaciers thawed, sea levels rose, and now the sinkhole is a 1000 foot wide, 412 foot deep jewel nestled in the Belize Barrier Reef.
Boulder Sinkhole
Some sinkholes are entirely manmade. A sinkhole opened up in April 2013 in Boulder, Colorado when a water main broke. The sinkhole was 15 feet wide and 30 feet long and did some damage to the neighborhood. Small urban sinkholes often occur because of the collapse of degraded water and sewer systems. There are many examples of very large and dramatic sinkholes, but small sinkholes are common as well and can be a big pain, especially if they end up in your neighborhood.