The Wandering Mind


Earth’s Great Holes

Posted in Miscellany by wandren on 30 June 2009
Diamond Mine in Kimberley, Africa

Diamond Mine in Kimberley, Africa

Kimberley, Africa: From mid-July 1871 to 1914, 50,000 miners dug the hole with picks and shovels, yielding 2,722 kg of diamonds. The Big Hole has a surface of 17 hectares (42 acres) and is 463 metres wide. It was excavated to a depth of 240m, but then partially infilled with debris reducing its depth to about 215 m; since then it has accumulated water to a depth of 40 m leaving 175 m visible. The underground Kimberly Mine was mined to a depth of 1097 metres.  A popular local myth claims that it is the largest hand-dug hole on the world, however Jagersfontein Mine appears to hold that record.[3] There is currently an effort in progress to register the Big Hole as a World Heritage Site.

Monticello Dam Spillway, California

Monticello Dam Spillway, California

“The Glory Hole,” Monticello Dam, California: Monticello Dam is located on Putah Creek where the stream crosses the eastern boundary of Napa County.  It regulates flows along the lower reaches of Putah Creek and stores surplus water.

The dam is a concrete, medium-thick arch structure with a height of 304 feet above the foundation and a crest length of 1,023 feet.  The dam is notable for its classic, uncontrolled spillway with a rate of 48,400 cubic feet per second (1370 m³/s) and a diameter at the lip of 87 feet (22 m).

Kennecott Copper Mine, Utah

Kennecott Copper Mine, Utah

The world famous Bingham Canyon Mine has produced more copper than any other mine in history. It is one of two man made objects seen from space. To give you some idea about the size of this mine, it’s three-quarters of a mile deep and more than 23/4 miles across at the top.

Ambergris Caye, Belize

Ambergris Caye, Belize

The Great Blue Hole is a large underwater sinkhole off the coast of Belize. It lies near the center of Lighthouse Reef, a small atoll 100 kilometres (62 mi) from the mainland and Belize City. The hole is circular in shape, over 300 metres (984 ft) across and 125 metres (410 ft) deep.[1] It was formed as a limestone cave system during the last glacial period when sea levels were much lower. As the ocean began to rise again, the caves flooded, and the roof collapsed.[2] Believed to be the world’s largest feature of its kind, the Great Blue Hole is part of the larger Belize Barrier Reef Reserve System, a World Heritage site of the United Nations Educational, Scientific and Cultural Organization (UNESCO).[1]


Mir Mine, Siberia

Mir Mine, Siberia

Mirny, Eastern Siberia: Winter temperatures in Mirny, a town just below the Arctic Circle, average –40 Celsius.The town was founded in 1955 when geologists came to exploit the area’s substantial mineral wealth. Consequently, Mirny’s defining feature is a 1 1/2 km wide, 500 m deep hole, which is the now-abandoned diamond mine.The town is strictly off limits to outsiders without a special permit and the authorities regard any foreigners with considerable suspicion.

Photo Courtesy of The Diavik Diamond Mine

Photo Courtesy of The Diavik Diamond Mine

The Diavik Diamond Mine has become an important part of the regional economy, employing 700, grossing C$100 million in sales, and producing 8 million carats (1600 kg) of diamonds annually. The area was surveyed in 1992 and construction began in 2001, with production commencing in January 2003. It is connected by an ice road and Diavik Airport with a 5,235-foot (1,596 m) gravel runway regularly accommodating Boeing 737 jet aircraft.

February 24, 2007

February 24, 2007

Giant Sinkhole in Guatamala, 2007:  330-foot-deep sinkhole swallowed a dozen homes, killed 3 people, and forced the evacuation of nearly 1,000 people in a crowded Guatemala City neighborhood.

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