Colo is a
stratovolcano
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and per ...
in
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
. It forms the small island of
Una-Una at the middle of the
Gulf of Tomini
The Gulf of Tomini ( id, Teluk Tomini), also known as the Bay of Tomini, is the equatorial gulf which separates the Minahassa Peninsula, Minahassa (Northern) and East Peninsula, Sulawesi, East Peninsulas of the island of Sulawesi (Celebes) in In ...
, the northern part of
Sulawesi
Sulawesi (), also known as Celebes (), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Ar ...
. The volcano is broad and has a low profile with only
above the sea level. It contains a wide
caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...
with a small
volcanic cone inside. Only three eruptions have been recorded in the history with two of them causing damage.
1898 eruption
The eruption had a
VEI of 3, qualifying as 'severe'. It involved:
*Central vent eruption
*
Crater lake eruption(?)
*Explosive eruption
*
Lahar
A lahar (, from jv, ꦮ꧀ꦭꦲꦂ) is a violent type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a river valley.
Lahars are extreme ...
s
The island was evacuated, and there was damage to property.
1983 eruption
This eruption was more violent and had a VEI of 4. It involved:
* Central vent eruption
* Explosive eruption
*
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 bu ...
(s)
*
Phreatic explosion
A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, occurs when magma heats ground water or surface water. The extreme temperature of the magma (anywhere from ) causes near-instantaneous evapo ...
The island was evacuated, and there was damage to property, but there were no deaths.
See also
*
List of volcanoes in Indonesia
References
{{reflist
Stratovolcanoes of Indonesia
Colo (volcano)
Mountains of Indonesia
Calderas of Indonesia
20th-century volcanic events
19th-century volcanic events