San Salvador volcano
El Salvador, 13.73°N / -89.29°W
Current status: normal or dormant (1 out of 5)
San Salvador volcano is a massive stratovolcano immediately northwestwest of El Salvador city. Its modern summit cone is also called the Boqueron stratovolcano. It formed within a 6 km wide caldera left by the collapse of the predecessor volcano about 40,000 years ago. Remnants of the caldera rim form the Picacho and Jabalí peaks.
Boqueron volcano is truncated by a steep-walled, 500 m deep and 1500 m wide summit crater, which formed during a large eruption about 800 years ago. Before the last eruption in 1917, the crater of Boqueron contained a 400 m wide lake, which was replaced by a small, 30 m high young cinder cone, called Boqueroncito, built during the eruption along with a major lava flow on the north flank.
Most historical eruptions from San Salvador originated from flank vents.
San Salvador volcano eruptions: 1917, 1806 (?), 1671, 1658, 1572 ± 2, ?1200, 640 AD ± 30 years
Latest nearby earthquakes
| Time | Mag. / Depth | Distance/Location | ||
| Tuesday, May 30, 2023 GMT (1 quake) | ||||
| May 30, 2023 1:59 am (GMT -6) (May 30, 2023 07:59 GMT) | 2.0 75 km | 36 km (22 mi) 21 km southeast of Sonsonate, El Salvador | ||
Background
The San Salvador or Quezaltepeque volcanic center formed in the southern part of the main graben of El Salvador and is dominantly andesitic. 3 fracture zones that extend beyond the base of San Salvador volcano have been the locus for numerous flank eruptions, including 2 that formed maars on the WNW and SE sides.Most of the 4 historical eruptions recorded since the 16th century have originated from flank vents, including two eruptions in the 17th century from the NW-flank cone of El Playón, during which explosions and a lava flow damaged inhabited areas.
A small seismic swarm occurred in August 1999, when volcano-tectonic earthquakes about 5 km from the crater were detected. No other signs of unrest were noted.
The last eruption of San Salvador volcano began on 6 June 1917 following strong and destructive earthquakes lasting for 2 hours. The eruption consisted of an effusive fissure eruption on the NW flank followed by a moderately explosive summit eruption (similar, but smaller in scale, to the Eyafjallajökull eruption in 2010).
The effusive phase produced a large aa lava flow on the NW flank, left a row of cinder cones on the eruptive fissure, and lasted about a week. The second phase started simultaneously with the waning of the waning of the first phase from a fissure vent inside the summit crater. It quickly evaporated a former 400 m wide lake and built the small Boqueroncito cinder cone. ...more
See also: Sentinel hub | Landsat 8 | NASA FIRMS
