Mount Malinao is a potentially active

stratovolcano A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with ...

located in the

Bicol Region The Bicol Region, designated as Region V, is an administrative region of the Philippines. It comprises six Provinces of the Philippines, provinces, four on the Bicol Peninsula (the luzon#Southeastern Luzon, southeastern end of Luzon): Albay, Ca ...

of the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

. The

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

displays strong

fumarolic A fumarole (or fumerole) is a vent in the surface of the Earth or another rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...

activity which is harnessed for generating

electricity Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

. Located on its slope is Tiwi Geothermal Power Plant, one of the first

geothermal energy Geothermal energy is thermal energy extracted from the crust (geology), crust. It combines energy from the formation of the planet and from radioactive decay. Geothermal energy has been exploited as a source of heat and/or electric power for m ...

plant commissioned in the country.

Location

Malinao Volcano is situated between the

provinces A province is an administrative division within a country or state. The term derives from the ancient Roman , which was the major territorial and administrative unit of the Roman Empire's territorial possessions outside Italy. The term ''provi ...

Albay Albay (IPA: ), officially the Province of Albay (; ; Baybayin, ᜎᜎᜏᜒᜄᜈ᜔ ᜈᜅ᜔ ᜀᜎ᜔ᜊᜌ᜔), is a Provinces of the Philippines, province in the Bicol Region of the Philippines, mostly on the southeastern part of the isla ...

and

Camarines Sur Camarines Sur (; ), officially the Province of Camarines Sur (Central Bikol language, Bikol: ''Probinsya kan Habagatan na Camarines''; ), is a Provinces of the Philippines, province in the Philippines located in the Bicol Region on Luzon. Its ca ...

in the southeastern region of

Luzon Luzon ( , ) is the largest and most populous List of islands in the Philippines, island in the Philippines. Located in the northern portion of the List of islands of the Philippines, Philippine archipelago, it is the economic and political ce ...

Island; about north-northwest of

Mayon volcano Mayon (; , ), also known as Mount Mayon and Mayon Volcano is an active stratovolcano in the province of Albay in Bicol, Philippines. A popular tourist spot, it is renowned for its "perfect cone" because of its symmetric conical shape, and i ...

, the most active volcano in the Philippines.

Physical features

The mountain is forested with an elevation of

above sea level Height above mean sea level is a measure of a location's vertical distance (height, elevation or altitude) in reference to a vertical datum based on a historic mean sea level. In geodesy, it is formalized as orthometric height. The zero level ...

and a base diameter of . On the summit of the volcano is a large crater with bare inner walls that are breached on the eastern side. On the lower flank this side of the predominantly

andesitic Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...

volcano, is

's largest

solfatara A fumarole (or fumerole) is a vent in the surface of the Earth or another rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...

s and

hot spring A hot spring, hydrothermal spring, or geothermal spring is a Spring (hydrology), spring produced by the emergence of Geothermal activity, geothermally heated groundwater onto the surface of the Earth. The groundwater is heated either by shallow ...

s, some of which deposit

siliceous sinter Geyserite, or siliceous sinter, is a form of opaline silica that is often found as crusts or layers around hot springs and geysers. Botryoidal geyserite is known as fiorite. Geyserite is porous due to the silica enclosing many small cavities. Si ...

. Naglagbong and Jigabo are two thermal wells located on the volcano. Temperatures up to were recorded on the fumaroles of Naglagbong.

Tiwi Geothermal Power Plant

This area was one of the first studied for generating electricity starting with a 250 kW power plant in 1967. In 1979, the first of the three 110 MW geothermal power plant was commissioned that year; the other two, in 1980 and 1982. At its peak, the plant was producing a maximum of 330 MW output. Recently, the 1979 plant was decommissioned due to decrease in steam supply.(2008-02-24)
"Geothermal Energy Resources in the Philippines"
JCMiras.net. Retrieved on 2011-09-24.

Classification

The

Philippine Institute of Volcanology and Seismology The Philippine Institute of Volcanology and Seismology (PHIVOLCS, ; ) is a Philippine national institution dedicated to provide information on the activities of volcanoes, earthquakes, and tsunamis, as well as other specialized information and ...

(PHIVOLCS), the government bureau that deals with volcanism in the country classifies Malinao as a potentially active volcano.

Eruptions & activities

There are no historical eruptions from Malinao which is believed to have been active from about 500,000 years ago until 60,000 years ago.

1970 earthquake swarms

There was an increase in

seismicity Seismicity is a measure encompassing earthquake occurrences, mechanisms, and magnitude at a given geographical location. As such, it summarizes a region's seismic activity. The term was coined by Beno Gutenberg and Charles Francis Richter in 194 ...

in 1970 accompanied by rumbling noises in Malinao prompting an issue of warning that the mountain might be reactivating. The tremors detected were ranging from 1 to 5 in intensity.

Small explosion in 1980

There was a minor phreatic explosion in the Naglagbong pool area in Tiwi on July 29, 1980, ejecting mud and rocks up to , reaching in height and distances up to . One person was injured and two buildings were damaged by the explosion. Prior to the event, as early as July 6, the area was experiencing unusual

microseism In seismology, a microseism is defined as a faint earth tremor caused by natural phenomena. Sometimes referred to as a "hum", it should not be confused with the anomalous acoustic phenomenon of the The Hum, same name. The term is most commonly used ...

s recorded at seismic station of the Commission on Volcanology (COMVOL) - the predecessor of PHIVOLCS - in the area.

Geyser A geyser (, ) is a spring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particular hydrogeological conditions that exist only in a few places on Ea ...

ing was also observed on the pool, two hours before the explosion. One theory about the cause of the explosion was water drawdown during the development of the Tiwi geothermal field.

Mythology

The volcano is believed to be the home of the ancient Bicolano god of beasts, Asuang, who challenged the supreme god of the Bicolano, Gugurang. He is worshiped alongside his friend, Bulan, the boy-god of the moon.

References

External links

Malinao
Philippine Institute of Volcanology and Seismology (PHIVOLCS) site. * {{DEFAULTSORT:Malinao Stratovolcanoes of the Philippines Subduction volcanoes Volcanoes of Luzon Mountains of the Philippines Landforms of Albay Landforms of Camarines Sur Potentially active volcanoes of the Philippines Pleistocene stratovolcanoes