By ExploreNow Editor, on May 13th, 2012%
Volcano Type: Shield volcano
Volcano Status: Holocene
Last Known Eruption: Unknown
Summit Elevation: 2024 m 6,640 feet
Latitude: 0.20°N 0°12’0″N
Longitude: 6.58°E 6°35’0″E
Pico de São Tomé is the highest mountain in São Tomé and Príncipe at 2,024 metres. It lies just west of the centre of São Tomé Island in the Obo National Park. The second highest point, Pico Ana Chaves, lies to its south east. The mountain is forested and accessible only on foot.
Sao Tome is a roughly conical island in the Gulf of Guinea that rises to a height of 2024 m from a depth of 3000 m below sea level. The southern and western parts of the island are more dissected, and dramatic phonolitic and trachytic spines rise vertically out of the rain forest. Most of the lavas erupted over the last million years are basaltic in composition. The youngest dated volcanic rock on Sao Tome is 0.1 million years old. However, the Sao Tome shield volcano is dotted with numerous morphologically recent cinder cones, many of which are concentrated on the SE side of the island.
 Pico de São Tomé  Pico de São Tomé  Pico de São Tomé  Location of Pico de São Tomé Originally posted 2010-10-15 08:21:46.
By ExploreNow Editor, on April 29th, 2012%
Volcano Type: Fissure vents
Volcano Status: Radiocarbon
Last Known Eruption: 20 BC ± 75 years
Summit Elevation: 1950 m 6,398 feet
Latitude: 28.00°N 28°0’0″N
Longitude: 15.58°W 15°35’0″W
The largely Miocene-to-Pliocene island of Gran Canaria in the middle of the Canary archipelago has been strongly eroded into steep-walled radial gorges called barrancos. Three major volcanic structures form the circular 60-km-wide island, which has been modified by caldera collapse, gravitational edifice failure, and extensive erosion.
Middle Quaternary scoria cones and lava flows are found in the northern and eastern parts of the massive shield volcano, which is cut by a major NW-SE-trending rift zone that extends across the island and fed flows primarily to the NE. Very young basaltic cones and lava flows of Holocene age are situated within a NW-trending zone from Berrazales to Bandama and at Las Isletas, a peninsula on the NE coast. One cinder cone was radiocarbon dated at about 3000 years before present, and other cones and flows may be less than 1000 years old.
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Originally posted 2010-10-04 15:28:13.
By ExploreNow Editor, on April 25th, 2012%
 Krafla Lake
Volcano Type: Caldera
Volcano Status: Historical
Last Known Eruption: 1984
Summit Elevation: 818 m 2,684 feet
Latitude: 65.73°N 65°44’0″N
Longitude: 16.78°W 16°47’0″W
The Krafla central volcano, located NE of Myvatn lake, is a topographically indistinct 10-km-wide caldera that is cut by a N-S-trending fissure system. Eruption of a rhyolitic welded tuff about 100,000 years ago was associated with formation of the caldera. Krafla has been the source of many rifting and eruptive events during the Holocene, including two in historical time, during 1724-29 and 1975-84. The prominent Hverfjall and Ludent tuff rings east of Myvatn were erupted along the 100-km-long fissure system, which extends as far as the north coast of Iceland. Iceland’s renowned Myvatn lake formed during the eruption of the older Laxarhraun lava flow from the Ketildyngja shield volcano of the Fremrinamur volcanic system about 3800 years before present (BP); its present shape is constrained by the roughly 2000 years BP younger Laxarhraun lava flow from the Krafla volcanic system. The abundant pseudocraters that form a prominent part of the Myvatn landscape were created when the younger Laxarhraun lava flow entered the lake.
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Originally posted 2010-08-24 04:15:21.
By ExploreNow Editor, on April 17th, 2012%
 Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 1961
Summit Elevation: 1516 m 4,974 feet
Latitude: 65.03°N 65°2’0″N
Longitude: 16.75°W 16°45’0″W
Askja is a large basaltic central volcano that forms the Dyngjufjöll massif. It is truncated by three overlapping calderas, the largest of which is 8 km wide and may have been produced primarily from subglacial ring-fracture eruptions rather than by subsidence. A major rhyolitic explosive eruption from Dyngjufjöll about 10,000 years ago was in part associated with the formation of Askja caldera. Many postglacial eruptions also occurred along the ring-fracture. A major explosive eruption on the SE caldera margin in 1875 was one of Iceland’s largest during historical time. It resulted in the formation of a smaller 4.5-km-wide caldera, now filled by Öskjuvatn lake, that truncates the rim of the larger central caldera. The 100-km-long Askja fissure swarm, which includes the Sveinagja graben, is also related to the Askja volcanic system, as are several small shield volcanoes such as Kollatadyngja. Twentieth-century eruptions at Askja have produced lava flows from vents located mostly near Öskjuvatn lake.
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Originally posted 2010-08-24 04:15:19.
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