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VOLCANOES

Divided over the three mountain ranges (Guanacaste, Tileran and Central) are the 16 volcanoes of Costa Rica. Of these, 5 are active (Arenal, Irazu, Poas, Rincon de la Vieja and the Turrialba) and 2 are dormant (Barva and Orosi).

 

We can classify the volcanoes in different ways:

Breakdown by activity

  • Of the thousands of volcanoes, only a small fraction occasionally erupts. Those are the active volcanoes.
  • Most others have not had an eruption for many thousands, sometimes millions, of years. They are called the dead volcanoes.
  • Then you have the dormant volcanoes of which it is not certain whether they will ever erupt again

Subdivision by shape:

  • Caldera Volcano. When a volcano collapses after an eruption, a new volcano can later form in the crater of the old volcano.
  • Dome volcano When the lava is somewhat thicker in composition, it does not flow that far. Depending on the chemical composition of the lava, a dome volcano is formed.
  • Cone volcano. cone volcanoes can be found all over the world in the volcanic landscape. They are not famous or infamous because their eruptions cause little damage or other misery.
    Cone volcanoes are made up of lava fragments. They originate from the volcano vent or exhaust and accumulate around it after ejection.
  • Shield Volcano. In volcanoes of this type, the magma in the magma center is a thin liquid. Lava flows travel tens of kilometers, especially if the eruption lasts a long time. In this way, material does not always accumulate close to the crater, but spreads far into the surrounding area. Over time and countless eruptions with lava flows, a mountain with gentle slopes is formed. The mountain therefore looks more like a shield than a cone.
  • Stratovolcano. At these volcanoes, the magma is a thick liquid and is therefore difficult to penetrate to the earth's surface. The pressure in the magma hearth must first rise high and that can take a long time. Stratovolcanoes are dangerous when they erupt and the more time has passed since the previous eruption, the more violent the next one will be.

Description of the volcanoes in Costa Rica

Arenal

Species: Active Form: Stratovolcano Eruption Form: Stromboli Altitude: 1643 meters

The Arenal is perhaps the most beautiful and was the most active volcano in the world. With its perfect cone shape, the colossus rises majestically above the grassy plains and forests between La Fortuna de San Carlos and Laguna de Arenal. Because the volcano is very active, one should not get too close to this fire-breathing mountain, however, there are viewpoints around the mountain that, at a safe distance, give spectacular views of the volcano, both in and outside the national park. The last major eruption was on July 29, 1968; the inhabitants of the region did not see the Arenal as a volcano at the time, but as an ordinary mountain. This misunderstanding then came to light very clearly: after 3000 years of rest, the volcano exploded with great violence, without any warning. 78 people and many animals died in this eruption.

Irazu

Species: Active Form: Stratovolcano Eruption Form: Stromboli Altitude: 3432 meters

The still active, almost cone-shaped volcano last erupted in 1963. The volcano spewed ash continuously for two years, forcing people in the area to wear masks over their mouths. Today the volcano is a collection of large and smaller craters, some of which are still smoking. The volcano has been active again since 1993, and the periodic ash rains sometimes reach as far as Cartago, 32 kilometers away. Due to this activity, access to some craters is restricted. The name Irazu means 'thunder and earthquake mountain' in the language of the Indians.

Poas

Species: Active Form: Stratovolcano Eruption Form: Plinian Altitude: 2704 meters

The Poás Volcano became famous in 1910 when it blew a cloud of steam more than 6 km into the sky and could therefore be called the most powerful geyser in the world. At other times, this volcano sent columns of boiling water 1,000 feet (300 m) into the air.
It is suspected that such geyser behavior is a sign that the volcano is in decline. It forms when surface water seeps down and comes into contact with the heat source of very hot, but cooling magma.
The volcano has three craters, two of which have been dormant for a long time. One extinguished crater contains a lake. The other is covered with a miniature forest that is almost constantly clouded. The lowest, active crater, however, still offers a hellish sight, a barren lunar landscape of 1300 m in diameter and 300 m deep. Ashes made smooth by the rain form the bottom, laced with smoke the cinder cones and lava lumps that have been washed from the steaming walls. A hot mud lake steams at the bottom and turns from white to green as sulfur fumes are forced into it from below, turning the water into a sulfuric acid solution. Over the past few years, the Poás has been showing increasing geyser-like activity. The intervals between the eruptions have shortened and the associated sulfur gas and steam caused acid rain. This caused considerable damage to the local coffee plantations.

Rincon de la Vieja

Species: Active Form: Stratovolcano Eruption Form: Plinian Altitude: 1895 meters

The 14,084 hectare Parque Nacional Rincon de la Vieja is located in the province of Guanacaste. This rarely visited, but very interesting national park is located around the still active volcano Rincon de la Vieja. The last major eruption of the volcano took place in 1991. On a clear day you have a fantastic view from the crater rim of the Rincon de la Vieja. To the north lies Lake Nicaragua and to the west the Santa Rosa Park with the Golfo Papagayo beyond. Just south of the crater is the Laguna Jilguero, a lake that changes color every few years. According to some, the cause of this curious phenomenon is that the water collides with other mineral layers over time. No fewer than 30 rivers and streams originate in the Rincon de la Vieja National Park. Protecting this important water resource was the main reason for establishing the park. In the park you will encounter various hot water and sulfur springs.

Turrialba

Species: Active Form: Stratovolcano Eruption Form: Sthmbolic/Volcano Altitude: 3340 meters

The name of this volcano was given by the Spanish conquerors Torre Alba, white mountain. This is because of the white plume of smoke that came out of the crater mouth. The volcano has three craters. Signs of volcanic activity are visible between the craters, such as fumaroles. Constant seismic shocks are also observable. The volcano crater is only accessible by a very bad road.

Barva

Species: Dormant Form: Stratovolcano Eruption Form: Dormant Altitude: 2904 meters

The mountain is covered with dense tropical forest. At the top are three lakes, the Barva, the Copey and the Danta. There is no volcanic activity to be observed.

Orosi

Species: Dormant Form: Stratovolcano Eruption Form: Dormant Altitude: 1487 meters

This asymmetrical pyramid rises above the savannah landscape of Guanacaste. There is no volcanic activity to be observed.

The Dead Volcanoes:

Cocoa: 1659 meters (National Park of Guanacaste),

Cacho Negro: 2150 meters (Braulio Carrillo National Park)

Chato: 1100 meters (Arenal National Zone)

Coco: 634 meters (Isla del Coco National Park)

Miravalles: 2028 meters (Mountain Range of Guanacaste)

Platar: 2183 meters (Juan Castro Blanco National Park)

Povenir: 2267 meters (Juan Castro Blanco National Park)

Santa Maria: 1916 meters (Rincon de la Vieja National Park)

Tenorio: 1916 meters (Tenorio Volcano National Park)

  1. Coco: 634 meter (Nationaal park Isla del Coco)

    Miravalles: 2028 meter (Bergketen van Guanacaste)

    Platar: 2183 meter (Nationaal park Juan Castro Blanco)

    Povenir: 2267 meter (Nationaal park Juan Castro Blanco)

    Santa Maria: 1916 meter (Nationaal park Rincon de la Vieja)

    Tenorio: 1916 meter (Nationaal park vulkaan Tenorio)