Central America Volcanic Arc facts for kids

The Central American Volcanic Arc (often called CAVA) is a long chain of volcanoes. It stretches along the Pacific coast of Central America, all the way from Mexico to Panama. This chain of volcanoes is about 1,100 kilometers (680 miles) long. It formed because of an active subduction zone. This is where the Cocos Plate (a giant piece of Earth's crust) slides underneath the Caribbean Plate. This area has been very active with volcanoes and earthquakes for millions of years. Many volcanoes are found across different Central American countries. Some have been active a lot in the past, and some still are today.

How the Volcanoes Formed

The Cocos Plate is located along the western side of Central America. This plate is constantly moving and sliding under the Caribbean Plate. This process is called subduction, and it's what creates the volcanoes in the Central American Volcanic Arc.

Scientists believe this sliding started between two and three million years ago. However, the area has been geologically active for much longer, possibly up to 12 million years ago. The interaction of several tectonic plates, including the Cocos Plate, Caribbean Plate, North American Plate, and a smaller plate called the Coiba Plate, has helped keep these volcanoes active for millions of years. These plate movements continue to shape the land and cause volcanic activity in the region.

Active Volcanoes Today

The Central American Volcanic Arc has hundreds of different volcanic shapes. These include tall, cone-shaped stratovolcanoes, large bowl-shaped craters, and lava domes. When these volcanoes erupt, they often release ash and pieces of rock called tephra. Scientists use special dating methods to find out how old these deposits are. They believe many of these volcanoes have been erupting on and off for the past 200,000 years.

Some volcanoes in the area have had very big, explosive eruptions recently. For example, the Santa Maria volcano in Guatemala erupted on October 25, 1902. This was a huge Plinian eruption. It shot about twenty cubic kilometers of ash almost thirty kilometers (about 18 miles) into the sky! Most of this ash was very fine, like powder.

Another example is Cerro Negro, a 250-meter-tall volcano in northwest Nicaragua. It erupted in 1971, 1992, and 1995. The eruptions in the 1990s had similar types of magma (molten rock). However, the amount of water and carbon dioxide gas inside the magma was different for each eruption. This caused the 1992 eruption to be much more explosive than the one in 1995.

Other active volcanoes in Central America include:

• In El Salvador: Santa Ana, Izalco, and San Salvador volcanoes.
• In Nicaragua: Masaya volcano.
• In Costa Rica: Miravalles, Irazú, and Poás volcanoes.

Many of these volcanoes are still active today. They will likely continue to erupt in the future as the Earth's plates keep moving and shaping the region.

Images for kids

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  How a subduction zone works, where one plate slides under another.

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  The line of volcanoes in the Sierra Madre de Chiapas mountains.

See also

In Spanish: Arco volcánico centroamericano para niños