Lake Ilopango is a

crater lake Crater Lake ( Klamath: ) is a volcanic crater lake in south-central Oregon in the Western United States. It is the main feature of Crater Lake National Park and is a tourist attraction for its deep blue color and water clarity. T ...

which fills an 8 by 11 km: volcanic

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...

in central

El Salvador El Salvador, officially the Republic of El Salvador, is a country in Central America. It is bordered on the northeast by Honduras, on the northwest by Guatemala, and on the south by the Pacific Ocean. El Salvador's capital and largest city is S ...

, on the borders of the

San Salvador San Salvador () is the Capital city, capital and the largest city of El Salvador and its San Salvador Department, eponymous department. It is the country's largest agglomeration, serving as the country's political, cultural, educational and fin ...

La Paz La Paz, officially Nuestra Señora de La Paz (Aymara language, Aymara: Chuqi Yapu ), is the seat of government of the Bolivia, Plurinational State of Bolivia. With 755,732 residents as of 2024, La Paz is the List of Bolivian cities by populati ...

, and Cuscatlán departments. The caldera, which contains the second largest lake in the country and is immediately east of the capital city,

, has a scalloped to high rim. Any surplus drains via the Jiboa River to the Pacific Ocean. The local military airbase,

Ilopango International Airport Ilopango International Airport is an airport located on the eastern part of the city of San Salvador, El Salvador, once serving the city as its international airport until 1980 when it was replaced by the larger and more modern El Salvador In ...

, has annual airshows where international pilots from all over the world fly over San Salvador City and Ilopango lake.

Eruptive history

Four major

dacitic Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. ...

–

rhyolitic Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals ( phenocrysts) in an otherwise fine-grained groundmass. The miner ...

eruptions occurred during the late

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

and

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

, producing

pyroclastic flow A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of b ...

s and

tephra Tephra is fragmental material produced by a Volcano, volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, ...

that blanketed much of the country. The caldera collapsed most recently sometime between 410 and 535 CE (based on radiocarbon dating of plant life directly related to the eruption),, esp. p.27. which produced widespread

s and devastated Mayan cities; however, a team of scientists concluded that the volcanic eruption might have happened in , based on volcanic shards taken from ice cores in

Greenland Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

, levels of

sulphur Sulfur (American spelling and the preferred IUPAC name) or sulphur (English in the Commonwealth of Nations, Commonwealth spelling) is a chemical element; it has Symbol (chemistry), symbol S and atomic number 16. It is abundance of the chemical ...

recorded in ice cores from

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

, and radiocarbon dating of a charred tree found in volcanic ash deposits. The eruption is estimated to have produced around of

ejecta Ejecta (; ) are particles ejected from an area. In volcanology, in particular, the term refers to particles including pyroclastic rock, pyroclastic materials (tephra) that came out of a explosive eruption, volcanic explosion and magma eruption v ...

(

DRE DRE may refer to: * ''Dre'' (album), 2010 by American rapper Soulja Boy Tell 'Em, 2010 * Dre (given name) **Dr. Dre Andre Romell Young (born February 18, 1965), known professionally as Dr. Dre, is an American rapper, record producer, recor ...

—several times more than the

1980 eruption of Mount St. Helens In March 1980, a series of volcanic explosions and pyroclastic flows began at Mount St. Helens in Skamania County, Washington, United States. A series of Phreatic eruption, phreatic blasts occurred from the summit and escalated until a major ...

), which puts it at a rating of 6 on the

Volcanic Explosivity Index The volcanic explosivity index (VEI) is a scale used to measure the size of explosive volcanic eruptions. It was devised by Christopher G. Newhall of the United States Geological Survey and Stephen Self in 1982. Volume of products, eruption c ...

(VEI) and makes it one of the biggest volcanic events on Earth in the last 7,000 years.Greshko, M
Colossal volcano behind 'mystery' global cooling finally found
National Geographic. 23 August 2019. Fallout from the eruption column blanketed an area of at least with pumice and ash to a depth of at least , and an area of nearly to a depth of at least , which would have stopped all agricultural production in the most-severely affected area for decades. It is also theorized that the eruption and subsequent weather events and agricultural failures directly led to the abandonment of

Teotihuacan Teotihuacan (; Spanish language, Spanish: ''Teotihuacán'', ; ) is an ancient Mesoamerican city located in a sub-valley of the Valley of Mexico, which is located in the State of Mexico, northeast of modern-day Mexico City. Teotihuacan is ...

by the original inhabitants. It was hypothesized that this eruption caused the

extreme weather events of 535–536 The volcanic winter of 536 was among the most severe and protracted episodes of climatic cooling in the Northern Hemisphere in the last 2,000 years. The volcanic winter was caused by at least three simultaneous eruptions of uncertain origin, wit ...

in Europe and Asia, but this is unlikely given the research published in 2020 that dates the eruption to 431 CE. Later eruptions formed several

lava dome In volcanology, a lava dome is a circular, mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions ...

s within the lake and near its shore. The only historical eruption, which occurred from December 31, 1879, up to March 26, 1880, produced a

and had a VEI of 3. The lava dome reached the surface of the lake, forming the

islet An islet ( ) is generally a small island. Definitions vary, and are not precise, but some suggest that an islet is a very small, often unnamed, island with little or no vegetation to support human habitation. It may be made of rock, sand and/ ...

s known as Islas Quemadas.

Events

On July 5, 2004 the illusionist, Francis Fanci was tagged and submerged inside a trunk from which he emerged after thirty seconds. On the other hand, in 2004 Matthew Hatfield Knight, eldest son of the owner of the international consortium of Nike sports shoes, died of a heart attack while diving with his colleagues.

Scuba diving

Ilopango Lake is also known for its exceptional scuba diving opportunities. One of the standout spots is ''Cerros Quemados'', where divers can explore depths reaching up to . This unique location features an underwater 'sand beach'.

References

External links

Global Volcanism Program: Ilopango

Lake Ilopango
at

NASA Earth Observatory NASA Earth Observatory is an online publishing outlet for NASA which was created in 1999. It is the principal source of satellite imagery and other scientific information about the climate and the environment which are being provided by NASA for ...

website {{DEFAULTSORT:Ilopango Lakes of El Salvador Volcanoes of El Salvador Calderas of Central America Volcanic crater lakes VEI-6 volcanoes 1879 natural disasters 1880 natural disasters 1879 in El Salvador 1880 in El Salvador

Eruptive history

Events

Scuba diving

See also

References

External links