By ExploreNow Editor, on April 24th, 2012%
Volcano Type: Volcanic field
Volcano Status: Radiocarbon
Last Known Eruption: 400 AD ± 100 years
Summit Elevation: 3930+ m 12,894 feet
Latitude: 19.08°N * 19°5’0″N
Longitude: 99.13°W 99°8’0″W
The massive Chichinautzin volcanic field covers a 90-km-long, E-W-trending area immediately south of Mexico City. The Sierra Chichinautzin, formed primarily of overlapping small cinder cones and shield volcanoes, creates a broad topographic barrier at the southern end of the Basin of Mexico that extends from the eastern flank of Nevado de Toluca to the western flank of Iztaccíhuatl volcano. The volcanic field contains more than 220 Pleistocene-to-Holocene monogenetic vents. The best-known eruption occurred about 1670 radiocarbon years ago from the Xitle scoria cone, NE of the Volcán Ajusco lava-dome complex, which at 3930 m forms the highest peak of the Sierra Chichinautzin. The Xitle eruption produced a massive basaltic tube-fed lava flow that covered agricultural lands as well as pyramids and other structures of Cuicuilco and adjacent prehispanic urban centers. The southern part of Mexico City and the National University of México lie atop the distal end of the 13-km-long lava flow.
 Chichinautzin Click Here For The Rest Of Chichinautzin, México
Originally posted 2010-08-26 04:52:22.
By ExploreNow Editor, on April 20th, 2012%
Volcano Type: Stratovolcanoes
Volcano Status: Holocene
Last Known Eruption: Unknown
Summit Elevation: 1940+ m 6,365 feet
Latitude: 27.470°N 27°28’11″N
Longitude: 112.591°W 112°35’28″W
The Tres Vírgenes volcanic complex contains the only large stratovolcanoes in Baja California. The roughly 1940-m-high complex rises above the Gulf of California in the east-central part of the peninsula. Three volcanoes, El Viejo, El Azufre, and La Vírgen were constructed along a NE-SW line and are progressively younger to the SW.
The youngest volcano, La Vírgen, is an andesitic stratovolcano with numerous dacitic lava domes and lava flows on its flanks. A major plinian explosive eruption from a SW-flank vent was radiocarbon dated at about 6500 years ago, but Helium exposure and Uranium-series dates give a late-Pleistocene age for this event. An ash plume was reported from Tres Vírgenes volcano by a Spanish Jesuit priest while navigating the Gulf of California in 1746. No tephra deposits from such a young eruption have been found, but young undated andesitic lava flows at the summit could potentially be related to this event. A geothermal plant is located at the northern end of the complex near the margin of the Pleistocene El Aguajito caldera.
Originally posted 2010-10-07 06:08:30.
By ExploreNow Editor, on March 21st, 2012%
Volcano Type: Lava domes
Volcano Status: Historical
Last Known Eruption: 1982
Summit Elevation: 1150? m 3,773 feet
Latitude: 17.360°N 17°21’36″N
Longitude: 93.228°W 93°13’40″W
El Chichón is a small, but powerful trachyandesitic tuff cone and lava dome complex that occupies an isolated part of the Chiapas region in SE México far from other Holocene volcanoes. Prior to 1982, this relatively unknown volcano was heavily forested and of no greater height than adjacent nonvolcanic peaks. The largest dome, the former summit of the volcano, was constructed within a 1.6 x 2 km summit crater created about 220,000 years ago. Two other large craters are located on the SW and SE flanks; a lava dome fills the SW crater, and an older dome is located on the NW flank. More than ten large explosive eruptions have occurred since the mid-Holocene. The powerful 1982 explosive eruptions of high-sulfur, anhydrite-bearing magma destroyed the summit lava dome and were accompanied by pyroclastic flows and surges that devastated an area extending about 8 km around the volcano. The eruptions created a new 1-km-wide, 300-m-deep crater that now contains an acidic crater lake.
 El Chichón Click Here For The Rest Of El Chichón, México
Originally posted 2010-08-22 04:15:51.
By ExploreNow Editor, on March 5th, 2012%
Volcano Type: Cinder cones
Volcano Status: Historical
Last Known Eruption: 1952
Summit Elevation: 3860 m 12,664 feet
Latitude: 19.85°N * 19°51’0″N
Longitude: 101.75°W 101°45’0″W
The widespread Michoacán-Guanajuato volcanic field contains over 1400 vents, including the historically active cinder cones of Parícutin and Jorullo, covering a 200 x 250 km wide area of Michoacán and Guanajuato states in west-central México. Cinder cones are the predominant volcanic form, but small shield volcanoes, lava domes, maars and tuff rings (many in the Valle de Santiago area), and coneless lava flows are also present. The shield volcanoes are mostly Pleistocene in age, and have morphologies similar to small Icelandic-type shield volcanoes, although the Michoacán-Guanajuato shields have higher slope angles and smaller basal diameters. Jorullo, which was constructed in the 18th century, and Parícutin, which grew above a former cornfield during 1943-52, are the two best known of the roughly 1000 small volcanic centers scattered throughout the volcanic field.
Click Here For The Rest Of Michoacán-Guanajuato, México
Originally posted 2010-08-09 03:42:49.
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