The Jolo Group of Volcanoes, more commonly referred to as the Jolo Group, are an active
group of
volcanoes in the
island of
Jolo in Southern
Philippines. The
Global Volcanism Program lists Jolo as one of the active volcanoes in the Philippines
while the
Philippine Institute of Volcanology and Seismology (PHIVOLCS) collectively list the group as
Bud Dajo, one of the
cinder cone
A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions o ...
s on the island.
Location
Jolo is a volcanic island located southwest of the southern tip of the
Zamboanga Peninsula of
Mindanao Island. The island is part of the
Sulu Archipelago, in the
province of
Sulu
Sulu (), officially the Province of Sulu (Tausug language, Tausūg: ''Wilāya sin Lupa' Sūg''; tl, Lalawigan ng Sulu), is a Provinces of the Philippines, province of the Philippines in the Sulu Archipelago and part of the Bangsamoro, Bangsamor ...
, located within the
Autonomous Region in Muslim Mindanao, one of the
Regions of the Philippines
In the Philippines, regions ( fil, rehiyon; ISO 3166-2:PH) are administrative divisions that primarily serve to coordinate planning and organize national government services across multiple local government units (LGUs). Most national governm ...
.
Physical features
The figure-eight shaped island is about at its longest, about at its widest and about at the narrowest section. The volcanic island is dotted with
cinder cone
A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions o ...
s,
tuff cones,
pyroclastic cones
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...
,
maar
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow ...
s and
crater lakes.
The highest point in the island is Mount Tumatangas
with an elevation of
asl
American Sign Language (ASL) is a natural language that serves as the predominant sign language of Deaf communities in the United States of America and most of Anglophone Canada. ASL is a complete and organized visual language that is express ...
.
Bud Dajo has an elevation of asl.
Guimba, Matanding, and Sungal, are some other volcanic cones near Bud Dajo. Four crater lakes are located on the island:
Lake Seit Lake Seit, also spelled Siit or Siet, is a volcanic lake on the island of Jolo
Jolo ( tsg, Sūg) is a volcanic island in the southwest Philippines and the primary island of the province of Sulu, on which the capital of the same name is situated ...
, Lake Panamao and Lake Timpuak and Sani Crater Lake.
Solfataric activity is found at Seit Lake.
Volcanic activity
On January 4, 1641, a volcanic eruption covered much of Mindanao in darkness and sent showers of ash as far as Cebu and Panay. It was reported at the time as being from a small island "opposite the main river of Jolo" and the only possible source of eruption in Jolo is Mount Dakula near Lake Panamao.
Some Philippine Volcanoes
From recent studies, the eruption was finally attributed to Mount Parker in South Cotabato.
A tsunami occurred in 1897, believed to have been caused by a local submarine eruption on September 21, 1897. It is possible this eruption was centered at Lake Seit, a volcanic maar
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow ...
with still active solfatara.
Volcanoes in the Jolo Group are young and considered active on the probable eruptions above.
Geology
Rock types are predominantly basalt and andesite.
Jolo Group is part of the Sulu Volcanic Arc
Sulu (), officially the Province of Sulu ( Tausūg: ''Wilāya sin Lupa' Sūg''; tl, Lalawigan ng Sulu), is a province of the Philippines in the Sulu Archipelago and part of the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM).
Its cap ...
, one of the two northeastern arms of the Sunda Plate
The Sunda Plate is a minor tectonic plate straddling the Equator in the Eastern Hemisphere on which the majority of Southeast Asia is located.
The Sunda Plate was formerly considered a part of the Eurasian Plate, but the GPS measurements have ...
which is in collision with the Philippine Mobile Belt
In the geology of the Philippines, the Philippine Mobile Belt is a complex portion of the tectonic boundary between the Eurasian Plate and the Philippine Sea Plate, comprising most of the country of the Philippines. It includes two subduction z ...
. It is an area of frequent earthquakes and volcanic activity.
Like most volcanos in the former Sultanate of Sulu, the group is little studied scientifically.
All volcanos in the Philippines are part of the Pacific ring of fire.
Political
Because of aggravated political unrest, kidnappings of foreigners in 2009, and fighting between political independence and government forces, visitors are strongly recommended to keep away from the Jolo islands.
See also
* List of active volcanoes in the Philippines
* List of potentially active volcanoes in the Philippines
* List of inactive volcanoes in the Philippines
* Philippine Institute of Volcanology and Seismology
* Volcano
References
External links
Philippine Institute of Volcanology and Seismology (Phivolcs) homepage
{{DEFAULTSORT:Jolo Group
Stratovolcanoes of the Philippines
Subduction volcanoes
Volcanic groups
Volcanoes of Mindanao
Mountains of the Philippines
Active volcanoes of the Philippines
Landforms of Sulu