April 17 , 2016. EN . Cleveland .
April 17 , 2016.
Cleveland , Alaska :
AVO/USGS Volcanic Activity Notice
Current Volcano Alert Level: WATCH
Previous Volcano Alert Level: ADVISORY
Current Aviation Color Code: ORANGE
Previous Aviation Color Code: YELLOW
Issued: Saturday, April 16, 2016, 11:55 AM AKDT (20160416/1955Z)
Source: Alaska Volcano Observatory
Notice Number: 2016/A6
Location: N 52 deg 49 min W 169 deg 56 min
Elevation: 5676 ft (1730 m)
Area: Aleutians Alaska
Volcanic Activity Summary:
AVO detected an explosion at Cleveland Volcano in both infrasound (air pressure) and seismic data this morning at 10:58 AKDT (18:58 UTC). There are no recent satellite views since the detected explosion, but earlier views are obscured by clouds at about 30,000 feet above sea level.
Cleveland volcano forms the western portion of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. The volcano is located about 75 km (45 mi) west of the community of Nikolski, and 1500 km (940 mi) southwest of Anchorage. The most recent significant period of eruption began in February, 2001 and produced 3 explosive events that generated ash clouds as high as 39,000 ft above sea level. The 2001 eruption also produced a lava flow and hot avalanche that reached the sea. Since then, Cleveland has been intermittently active producing small lava flows, often followed by explosions that generate small ash clouds generally below 20,000 ft above sea level. These explosions also launch debris onto the slopes of the cone producing hot pyroclastic avalanches and lahars that sometimes reach the coastline.
16 APRIL 2016. Seismologists are watching the Cleveland volcano along the Aleutian chain after sensors showed an explosion, according to the Alaska Volcano Observatory (AVO). The explosion was recorded just before 11 a.m., AVO said in a statement.
“We detected an explosion using infrasound equipment, which basically senses air pressure and it can detect explosions from really far away, like in remote volcanoes like Cleveland,” said Jessica Larsen, with the University of Alaska Fairbanks Geophysical Institute. “And then it also showed up on the seismic data. So we would classify that as an eruption. Usually these eruptions from Cleveland can be short duration explosions and then some variable amount of time might pass before we see another one.”
Larsen said there was no evidence of increased activity at the volcano in the days leading up to the eruption. AVO was not able to get an immediate look at the volcano, as cloud coverage in the area prevented satellite viewing. So far no ash cloud has been reported and Larsen said no aviation warnings have been issued.
The volcano’s color code status was upgraded to orange while the alert level is at “watch,” currently. The Cleveland volcano is located on the western side of Chuginadak Island, an uninhabited island in the eastern Aleutian islands. The Tana volcano is also on the island, but Larsen said it is less active than Cleveland.
“We typically monitor Cleveland because it’s frequently active,” she said. The last significant activity exhibited by the Cleveland volcano occurred in 2001, according to AVO, when “three explosive events” created an ash cloud that went as high as 39,000 feet, as well as a lava flow and “hot avalanche” that reached the water.
Source : USGS AVO , KTVA.
Photos : AVO , Lyons, John; Schmitt, Joe