By ExploreNow Editor, on May 15th, 2012%
Volcano Type: Submarine volcano
Volcano Status: Historical
Last Known Eruption: 1996
Summit Elevation: -3000 m - 9,842 feet
Latitude: 42.67°N 42°40’0″N
Longitude: 126.78°W 126°47’0″W
The northernmost of five segments of the Gorda Ridge lies immediately south of the Blanco Transform Fault that offsets the Gorda and Juan de Fuca oceanic spreading ridges. The 65-km-long North Gorda Ridge segment is located about 200 km west of the southern Oregon coast and has deep 5- 10-km-wide valleys at either ends with a shallower narrow axial valley at the center. This morphology, which in plan view resembles an hourglass, is typical of magmatically active spreading segments. A submarine lava flow was erupted in late February and early March 1996, near the center of the North Gorda Ridge segment. The eruption was initially detected through acoustic T-waves from a seismic swarm and the emission of large thermal plumes. In April submarine cameras revealed new lava flows about 100-200 m wide along a fissure that was at least 3.5 km long. A seismic swarm of uncertain origin also occurred at this location in January 1998.
Click Here For The Rest Of North Gorda Ridge, North Eastern Pacific Ocean
Originally posted 2010-09-01 04:40:38.
By ExploreNow Editor, on April 7th, 2012%
Volcano Type: Stratovolcano
Volcano Status: Radiocarbon
Last Known Eruption: 870 AD ± 100 years
Summit Elevation: 744 m 2,441 feet
Latitude: 17.60°N 17°36’0″N
Longitude: 145.83°E 145°50’0″E
 Volcanic deposits Alamagan is the emergent summit of a large stratovolcano in the central Mariana Islands with a roughly 350-m-deep summit crater east of the center of the island. The exposed cone is largely Holocene in age. A 1.6 x 1 km graben cuts the SW flank. An extensive basaltic-andesite lava flow has extended the northern coast of the island, and a lava platform also occurs on the south flank. Pyroclastic-flow deposits erupted about 1000 years ago have been dated, but reports of historical eruptions were considered invalid (Moore and Trusdell, 1993).
 Alamagan Click Here For The Rest Of Alamagan, Mariana Islands
Originally posted 2010-09-06 12:06:17.
By ExploreNow Editor, on January 29th, 2012%
Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 2008
Summit Elevation: 790 m 2,592 feet
Latitude: 16.35°N 16°21’0″N
Longitude: 145.67°E 145°40’0″E
The elongate, 9-km-long island of Anatahan in the central Mariana Islands consists of a large stratovolcano with a 2.3 x 5 km, E-W-trending compound summit caldera. The larger western portion of the caldera is 2.3 x 3 km wide, and its western rim forms the island’s 790-m high point. Ponded lava flows overlain by pyroclastic deposits fill the floor of the western caldera, whose SW side is cut by a fresh-looking smaller crater. The 2-km-wide eastern portion of the caldera contained a steep-walled inner crater whose floor prior to the 2003 eruption was only 68 m above sea level. A submarine volcano, named NE Anatahan, rises to within 460 m of the sea surface on the NE flank of the volcano, and numerous other submarine vents are found on the NE-to-SE flanks. Sparseness of vegetation on the most recent lava flows on Anatahan had indicated that they were of Holocene age, but the first historical eruption of Anatahan did not occur until May 2003, when a large explosive eruption took place forming a new crater inside the eastern caldera.
Click Here For The Rest Of Anatahan, Mariana Islands,
Originally posted 2010-08-25 03:51:02.
By ExploreNow Editor, on January 4th, 2012%
Volcano Type: Stratovolcanoes
Volcano Status: Historical
Last Known Eruption: 2006
Summit Elevation: 570 m 1,870 feet
Latitude: 18.13°N 18°8’0″N
Longitude: 145.80°E 145°48’0″E
Pagan Island, the largest and one of the most active of the Mariana Islands volcanoes, consists of two stratovolcanoes connected by a narrow isthmus. Both North and South Pagan stratovolcanoes were constructed within calderas, 7 and 4 km in diameter, respectively. The 570-m-high Mount Pagan at the NE end of the island rises above the flat floor of the northern caldera, which may have formed less than 1000 years ago. South Pagan is a 548-m-high stratovolcano with an elongated summit containing four distinct craters. Almost all of the historical eruptions of Pagan, which date back to the 17th century, have originated from North Pagan volcano. The largest eruption of Pagan during historical time took place in 1981 and prompted the evacuation of the sparsely populated island.
 Pagan Volcano eruption in 1994 Click Here For The Rest Of Pagan, Mariana Islands
Originally posted 2010-08-27 03:17:05.
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