Costa Rica Volcanoes

In Costa Rica there are 112 volcanic formations. They belong to so called Pacific Rim of Fire. Seven of them is considered as active ones. Their activity is connected with fertile soils, which cover the majority of Costa Rica territory. Their suddenly erruptions made in past years huge destructions. The highest Costa Rica`s volcanoe is Irazu, the most active is Arenal and Poas has the second widest crater in the world. (diameter 1,5 kilometres). In 1950`s, the terrains around each Costa Rican volcanoes were decided to be under protection. Many of them are within the national parks. Costa Rica major volcanic peaks are stratovolcanoes. The type of magma that fuels most Costa Rica volcanoes is thick, viscous, and so filled with gases that the erupting magma often blasts violently into the air. The most serious eruption was that of Irazu volcanoe in 1963. It erupted clouds of smoke and ash that kept shovering over San Jose and other parts for two years. People had been walking with handkerchief. From roofs on every day were being scraped layels of polders of even 13 centimetres thickness. Over 100 square kilometers of the surrounding land were devastated. The latest eruption in Costa Rica was of Arenal Volcanoe on August 24th, 2000. One person died and two were severly hurt. 600 residents have been evacuated.

• Volcano Irazu

(3.432 m.a.s.l.). The highest volcano in the country. It`s the only place in America, from which it`s possible to see both oceans at once. On its slopes there are strawberries cultivations. There is a smell of sulphur on its top.

Its main crater is round shaped and is filled with green water with sulphur and measures 1050 metres of wide and 300 metres of depth. The second crater Diego da la Haya (called that way in honour of spanish concvistador Fernandeza Diego de la Haya, who as the first recorded its eruption from XVIII century), has 600 metres of width and 100 metres of depth. The other craters are: Playa Hermosa, El Piroklastico and La Laguna. The name Irazu (Iztaru) derives from the language of Indians which used to live under its slopes. It means “a thunder” or “the place that shakes”.

Irazu had a few catastrophic eruptions. That one from 1723 destroyed completely off that time capital – Cartago. The eruption from 19 June 1963 covered San Jose with thick layer of ash. There was conviction that Irazu blows out on every 30 years. It`s called :”the deadly keg of powder”.

• Volcano Turrialba:
It`s the most easterntip volcanoe of the Cordillera Central (the second volcanoe in the country in respect of metres above sea level-3.339). It has been active since 6.300 BC. In colonial times that was nicknamed by Spaniards as Torre Alba “white tower”, because of its eruptions gave the impression of a huge white tower. It has three craters. To the main of them doesn`t lead any way. The catastrophic eruptions happened also in 1723, 1847, 1853, 1855 and 1861. Now the scientists claim its new eruption might be expected.  In March 2001 around volcanoe was felt some tremours and shakes. Many residents of the nearby area were afraid that it is the new cycle of activity, but the scientists claimed the shakes had nothing to do with that.

• Volcano El Viejo:
(2.122 m.n.p.m.) It`s situated to the north-west off Poas volcanoe. It can be reached through Bajos del Toro or Toro Amarillo in Palmira. It used to be called La Mina (a mine), because of the old private pumice-stone mine, that existed there. Its slopes are covered by cypresses and cedars.It belongs to the Juan Castro Blanco National Park.

• Volcano Platanar:
(2.183 m.a.s.l.). A volcanic peak lied at the northernmost end of Cordillera Central, 7 kilometres south-east of the town of Quesada. It belongs to Juan Castro Blanco National Park.  There is no clear evidences of uruptive activity of that peak, but the thin layers of ashes covering in the eastern slope testified its activity within last few centuries. On its northern slope, flow the thermal springs.

• Volcano Poas:
2706 m.a.s.l It has three craters, only one active. It measures 1500 metres lengh (the second widest crater of the world), and 300 metres of depth. On its bottom there is the most active bubling lake in the world. Its geiser eruptions shooted at 40 metres above. To the north from the main crater, Von Frantzius crater (the oldest one) is situated (it`s named after german doctor who searched it in 1860). The third crater Botos is filled with blue water lake and ringed by thick forests. On the west side of volcano winds the Toro Amarillo river.

According to some people, its name comes from an indigenous Indian group who lives in the areas around. The other hipothesis says that it comes fromthe word “Poas” meaning “thorny”.  The first person to visit the volcano was Miquel Alforo in 1828. The first mention of Poas volcanic activity dates back to 1834. The first naturalist to visit Poas was the Dane Andres Sandoe Oersted in 1863. Its eruption from 1889 made an earthquake, due to which, a piece of volcanic wall was torn off and a deep hole filled with water was made. (Fraijanes Lake). During the eruption from 1910, the ash cloud was shot 8.000 metres into the air. In 1952-1954 there were similar clouds ashes substituted by deep tremors. Since 1989 the increase of gas emissions has been observed. It`s in charge of acid rains, that destroyed the strawberry plantations on the western side of volcanoe.  On June 2001, after seven years in which the level of the lake in the crater of Botos had remained unchanged, the scientists have noticed that there is ever less and less water. If the trend continues the geyser-like activity that characterized the volcano in the past is likely to return.

• Volcano Porvenir:
(2.267 m.a.s.l.). Large stratowulcano lying within the Chocosuela caldera. Its summit crater contains a small cone. A thin layer of ash suggest that an eruption occured within the past few thousand years. It belongs to Juan Castro Blanco National Park.

• Volcano Arenal:
The most active Costa Rica volcano. It rises at 1633 m.a.s.l. at the edge of San Carlosb Lowland, on the eastern side of the like with the same name, in Alajuela province. It`s quite young volcano, about 3.000 years old. The volcano lovers declared it as the third volcano in the world with the most perfect conical shape. It`s within the new-opened Arenal National Park.

During XX century it was passing a few eruptive phases. The biggest eruption of the latest years took place on 29 July of 1968. The morning explosion destroyed everything within the 15 kilometres. The settlements like Pueblo Nuevo and Tabacon were rubbed from the map. More or less 80 people have lost their lifes.

The following volcano eruptive activity recorded in 1975, when from the main crater the lava started to being appearing and flowing to Rio Tabacon. From June of 1984, Arenal come into new explosion phase. The ahes, muds and steam covered Arenal Lake and Tilaran town. Since that time on every day there are 3 – 20 explosions with lava flowing. It spawns house-sized rocks, sulfur dioxine and chloride gases and red-hot lava. It can be seen from the special view points.

The volcano activity was recorded also in 1993 and 1996. The last one happened on August 24th, 2000. One person have been killed, 2 hurt and 600 evacuated.

On March 2001 Arenal Volcano has displayed a new cycle of high activity, mainly in the shape of ash and gas eruptions. In 2001 the government established a buffer zone around the crater. The decree bans the construction of houses and tourist developments in a 5.5-kilometer

• Volcano Barva:
(2.906 m.a.s.l.). The oldest Costa Rica volcano. It`s within the boundary of Braulio Carillo National Park. Since 1492 is considered to be dormant. Its calderic structure make the eastern wall of Meseta Central. Two main craters are filled by lakes with clear and cold water. (Barva Lake-700 m. of width and Danta Lake-500 m. of width). Its slopes are dotted with coffee seedlings and covered with cypress and pines tree forests. It`s the only place in the world where lives where lives a toad Bufo Holdridge. (It`s inhabited also by Toad Harlequin).

• Volcano Cacao:
(1659 m.a.s.l.). It`s placed in the Cordillera Guanacaste range. It has an open crater towards the south-west of which there is no recorded activity. On its steep slopes, numerous streams and rivers are born that flow into lake Nicaragua and the Nicoya Gulf as in the case of Tempisgue river. On its slope, at an elevation 1.050 m.a.s.l. there is a Cacao Biological Station. It stands out also with a large number of petroglyphs

• Volcano Tenorio:
(1.916 m.a.s.l.) It`s in Guanacaste province. It`s the easternmost volcan of Cordillera Guanacaste.   It consists of four volcanic peaks and two twin-craters (sometimes called as separate volcan of Montezuma). It`s covered with savannah, rain forest at midelevation and above by clouds forests. From the western slope of Tenorio flows down the Tenorio river and from the southern slope rivers Tenorito and Martirio. From its top spreads the sight for Guatuso and San Carlos lowlands, Lake Nicaragua, Cano Negro National Reserve and Arenal Lake. From its slopes snakes down the Rio Frio. A legend exists of an eruption in 1816, but the volcano was observed to be densely forested in 1864 and is not considered to have erupted in historical time. Since 1989 it has been under a pre-feasibility study to determine its geothermal potential. In 1998 the vicinity of the volcano was hit by the 1 R scale earthquake.

Since 1995 the volcan is within Volcan Tenorio National Park. It`s known among others for the hot springs (with the temperatures up to 94 C) and bumbling holes. At the foot of Tenorio spread the plantations of macadamia.

• Volcano Miravalles:
(2.028 m.a.s.l.). It`s situated 15 kilometres off Bagaces, (the highest in Cordillera Guanacaste). It contains 5 cones along a North-East trending line. The only reported historical eruptive activity was a small steam explosion in 1946. On its slopes a few mud bumbling pots and thermal springs. On the volcanoe foot there is Costa Rica`s Electricity Institute geothermal project. In the middle of XIX century there was a trial of organizing German colonization. On cloudless days, from the top it`s possible to see Nicaragua Lake.

• Volcano Rincon de la Vieja
It was appeared about millions years ago. It means “the corner of old lady” and is attributed to indigenous people of the Guatuso tribe living on the eastern side of the volcano who believed that an old witch lived on top of the mountain and would send columns of smoke into the air whenever she got annoyed.

It has 9 craters (Rincon – 1.806 m.a.s.l., Von Seebach – 1.895 m.a.s.l., Santa Maria – 1.916 m.a.s.l.) and is considered as the third in respesct of activity volcanoe in Costa Rica. (Santa Maria crater is considered to be by some people as the separate volcano). It`s main crater has elipse shape, 500 metres of width and 100 metres of depth. On its bottom there is a hole with bumbling 250 Ceisius lava. In April 2000 the Canadian tourist has fallen to there for three days. To the east of crater there us a lake, waterfalls and bubling holes. In the terrain called Las Hornillas , the fumaroles hiss like kettles spitting up odiferous steam and gases. The last vital eruptions took place in 1966-1970. They were accompanied by clouds of ashes, earthquakes and tremors. The lighter eruptions took part in 1984, 1891 and 1996.

• Volcano Orosi:
(1.487 m.a.s.l.). The legent has it that in the past on the top of volcano climbed the Indian military groupe. There they were spotted by an earthquake. One of them was expected to screamed that it`s a sign for silver presence. From the depths of the volcano came a powerful, echoing voice replying, “Plata, no; oro, si.” (“Silver no, Gold Yes.”). It`s crater is covered by forests. The first study of this volcano was made by Carlos Sapper in 1899.

• Volcano Chato:
Its name means “the flat hill”. Its the volcanic formation with collapsed crater and with the idyllic lake within that (it`s possible to canoe on that). On August 2000 there was the plane crash, where 10 people have been killed. Another plane hit its slope on January 2001. One pilot died.

• Volcano Cacho Negro:
(2.136 m.a.s.l.). Extinct volcano that is situated in the central part of Braulio Carillo National Park. It`s known for its perfect conical shape. Its slopes are covered with cypress and pine forests. Around abound the cattle farms.

• Volcano Congo:
(2.014 m.a.s.l.). The southern one from the remnants of twin volcano. It come into existence around 1,5 million years ago. From its slopes originate two small brooklets that give water for nearby laguna Hule. In 1993 it was added within the Poas Volcano National Park.