(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170608/0025Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	ORANGE
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 53 deg 55 min W 168 deg 2 min
(9) Area:	Aleutians
(10) Summit Elevation:	492 ft (150 m)
(11) Volcanic Activity Summary:	A new lava dome has been observed in satellite data from earlier today. It is located in the northern portion of the vent lagoon, has breached sea level, and is about 110 m across. A robust steam plume is visible in satellite data, and at 2250 UTC (14:50 AKDT) extended for 75 km to the south over the western end of Unalaska Island at an estimated altitude of less than 10,000 ft asl. Some past eruptions of Bogoslof have ended with the emplacement of a lava dome, but in other cases, lava effusion has been followed by additional explosions. If future explosions do occur, the resulting volcanic cloud could be more ash-rich than those that have occurred thus far in the sequence that began in 2016. This level of activity is consistent with the current Aviation Color Code of ORANGE and the Volcano Alert Level of WATCH.
(12) Volcanic cloud height:	Less than 10,000 ft asl
(13) Other volcanic cloud information:	Steam-rich
(14) Remarks:
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Jessica Larsen, Acting Coordinating Scientist, UAF jflarsen@alaska.edu (907) 322-4085
(16) Next Notice:

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AVO/USGS Volcanic Activity Notice

Volcano: Bogoslof (VNUM #311300)

Current Volcano Alert Level: WATCH

Current Aviation Color Code: ORANGE

Issued: Wednesday, June 7, 2017, 4:25 PM AKDT
Source: Alaska Volcano Observatory
Notice Number:
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary: A new lava dome has been observed in satellite data from earlier today. It is located in the northern portion of the vent lagoon, has breached sea level, and is about 110 m across. A robust steam plume is visible in satellite data, and at 2250 UTC (14:50 AKDT) extended for 75 km to the south over the western end of Unalaska Island at an estimated altitude of less than 10,000 ft asl.

Some past eruptions of Bogoslof have ended with the emplacement of a lava dome, but in other cases, lava effusion has been followed by additional explosions. If future explosions do occur, the resulting volcanic cloud could be more ash-rich than those that have occurred thus far in the sequence that began in 2016.

This level of activity is consistent with the current Aviation Color Code of ORANGE and the Volcano Alert Level of WATCH.

Recent Observations:
[Volcanic cloud height] Less than 10,000 ft asl
[Other volcanic cloud information] Steam-rich
[Lava flow/dome] New lava dome observed
[Lava flow] N/A

Contacts: Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

Jessica Larsen, Acting Coordinating Scientist, UAF
jflarsen@alaska.edu (907) 322-4085

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

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