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Belknap is a shield volcano on the crest if the High Cascades of Oregon. This photo shows the central vent and associated lava flows. A kipuka of older lava is near the center of the photo. The volcano began erupting about 3,000 years ago. Most of the main shield formed between 1,775 and 1,496 years ago. Photo courtesy of the Oregon State Highway Tourism Division.
Stand on the Summit of Little Belknap and Look Around!
The view from the summit of Little Belknap, OR (Photosynth by Robert Peckyno)
(click and use the arrows to pan)
Sources of Information:
Taylor, E.M., 1987, Late High Cascade volcanism from the summit of McKenzie Pass, Oregon: Pleistocene composite cones on platforms of shield volcanoes: Holocene eruptive centers and lava fields: in Hill, M.L., ed., Centennial Field Guide Volume 1 Cordilleran Section of the Geological Society of America, p. 311-312.
Wood, C.A., and Kienle, J., 1993, Volcanoes of North America: Cambridge University Press, New York, 354 p.
A temple sits astride the Onioshidashi lava flow on the north flank of Asama volcano.
Photo by Richard Fiske, 1961 (Smithsonian Institution).
Asama, Honshu's most active volcano, overlooks the resort town of Karuizawa, 140 km NW of Tokyo. The volcano is located at the junction of the Izu-Marianas and NE Japan volcanic arcs. Asama is Honshu's most active volcano, and has an historical record dating back more than 1300 years.
Asama is a stratovolcano. Three overlapping bodies make up this volcano. It consists of a young stratovolcano with two craters lying on a shield volcano. The shield volcano rests on an older stratovolcano.
Kurohu-yama is the name of the western crater rim of the older stratovolcano. It stands 7888 ft (2405 m) high. Erosion has enlarged this crater to 1.25 miles (2 km) around. Water rests in the crater and is drained to the southwest. The eastern part of this stratovolcano has been down-faulted and buried under a shield volcano. A younger stratovolcano also lies on top of this shield.
Aoba is a shield volcano with a large shallow crater, called Manaro, which contains one or more lakes.
Manaro contains gas vents that can be heard some distance away, hot springs, and solfataras.
Most of Aoba is made of tephra but a few thin basaltic lava flows have been noted.
In 1995, there was a strong gas discharge event with large amplitude tremor at Aoba.
General map of Ambrym showing the main volcanic features (caldera, cones, maars, and fissures). Ambrym is the most voluminous active volcano in Vanuatu. Marum and Benbow are post-caldera cones. The caldera is similar in size to calderas associated with large Plinian eruptions. From Robin and others (1993).
Ambrym Island is a large shield volcano with a caldera. The caldera formed in about 50 A.D. with an eruption of VEI 6. It is also a very active volcano with 48 eruptions since 1774. Most of these eruptions are at cones inside of a caldera (5.5 by 7.5 miles; 9 by 12 km).The eruptions are explosive and usually from a central vent, There have been a few flank eruptions. Fifteen erupts produced lava flows. Ten eruptions involved a lava lake. There were fatalities in two eruptions at Ambrym. In 1894, six people were killed by volcanic bombs and four people were overtaken by lava flows. In 1913, 21 people were killed during an explosive eruption. Acid rainfall in 1979 burned some of the inhabitants. Local water supplies were contaminated and had a pH of 5.2-5.5.
This is a three-dimensional view of Alcedo volcano, on Isabela Island in the Galapagos Islands. This view (covering 75 by 60 km, or 47 by 37 miles) was made by combining a Space Shuttle radar image (SIR-C) and a topographic map. The picture has been stretched in the vertical direction nearly two times so that the volcano appears twice as high as it really is. This helps scientists see changes in the vol cano's shape. On this image you can see the Pacific Ocean at the bottom, and beyond the coastline are the slopes of Alcedo volcano which lead to its large caldera at the top. The bright features on the left are rough lava flows. In a radar image rough areas show up as bright because they reflect a lot of the radar beam; smooth areas (like the sea) are dark because there aren't many reflectors. Radar images like this tell us different information than we get from space photographs; thus the two types of remote sensing information are very useful when used together.