(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20171206/2009Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	UNASSIGNED
(5) Previous Color Code:	YELLOW
(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:	The last detected explosive activity at Bogoslof occurred on August 30, 2017. Over the past three months there has been no significant activity observed in seismic, infrasound, satellite or lightning data. Thus, we are decreasing the Aviation Color Code and Alert Level to UNASSIGNED. AVO only assigns Aviation Color Codes and Alert Levels to volcanoes that have a local seismic monitoring network. Activity at Bogoslof has been detected using instruments from distant sites, thus we can not say authoritatively that the volcano has returned to its normal background state. However, we are no longer detecting any activity that would be considered to be indicative of unrest. A resumption of eruptive activity is possible. It is likely that we would be able to detect significant explosive activity if it where to occur.
(12) Volcanic cloud height:	None
(13) Other volcanic cloud information:	N/A
(14) Remarks:
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Jeff Freymueller, Coordinating Scientist, UAFGI jfreymueller@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: UNASSIGNED
Previous Volcano Alert Level: ADVISORY

Current Aviation Color Code: UNASSIGNED
Previous Aviation Color Code: YELLOW

Issued: Wednesday, December 6, 2017, 11:09 AM AKST
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: The last detected explosive activity at Bogoslof occurred on August 30, 2017. Over the past three months there has been no significant activity observed in seismic, infrasound, satellite or lightning data. Thus, we are decreasing the Aviation Color Code and Alert Level to UNASSIGNED.

AVO only assigns Aviation Color Codes and Alert Levels to volcanoes that have a local seismic monitoring network. Activity at Bogoslof has been detected using instruments from distant sites, thus we can not say authoritatively that the volcano has returned to its normal background state. However, we are no longer detecting any activity that would be considered to be indicative of unrest.

A resumption of eruptive activity is possible. It is likely that we would be able to detect significant explosive activity if it where to occur.

Recent Observations:
[Volcanic cloud height] None
[Other volcanic cloud information] N/A
[Lava flow/dome] N/A
[Lava flow] N/A

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

Jeff Freymueller, Coordinating Scientist, UAFGI
jfreymueller@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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