This blog provides commentary on interesting geological events occurring around the world in the context of my own work. This work is, broadly, geological fluid dynamics. The events that I highlight here are those that resonate with my professional life and ideas, and my goal is to interpret them in the context of ideas I've developed in my research. The blog does not represent any particular research agenda. It is written on a personal basis and does not seek to represent the University of Illinois, where I am a professor of geology and physics. Enjoy Geology in Motion! I would be glad to be alerted to geologic events of interest to post here! I hope that this blog can provide current event materials that will make geology come alive.

Banner image is by Ludie Cochrane..

Susan Kieffer can be contacted at s1kieffer at gmail.com

Thursday, March 10, 2011

Vog (=volcanic fog) at the new eruption in Hawaii

Vog model from University of Hawaii
Source is here
Vog, the noxious mixture of sulfur dioxide and sulfate aerosols that creates a "volcanic fog"=vog, is being emitted at increased levels from the fissure eruption that has developed in Hawaii.  Vog can cause headaches, breathing problems, vulnerability to respiratory ailments, irritated eyes and throat.  So far, the northeast tradewinds are keeping the gas from populated areas, but if they diminish or change direction the vog could move toward populated areas. The March 10 report from HVO says that potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas.

Scientists at the University of Hawaii developed the concept of a Vog Measurement and Prediction (VMAP). If you click on the picture to the left, it should start a GIF animation. If it doesn't work, go to the site referenced in the caption. In 2008 the Halemaumau vent began emitting elevated sulfur dioxide gases, and the idea arose of trying to do vog forecasting.  Steven Businger and Roy Huff of U.H. developed some preliminary concepts and fortunately, Stimulus Act funding to HVO allowed development of a feasibility study.  Preliminary products are on the WWW site referenced in the figure caption.

The east rift eruption has been called the March 5 Kamoamoa fissure eruption.  The activity diminished through the 9th, and paused at 10:30 p.m.  The sulfur dioxide emission rate was estimated at 5,000 tonnes/day from the east rift sources. At the summit of Kilauea, the lava lake remains deep below the rim of the vent (220 m or 720 feet) in Halemaumau. The sulfur dioxide emission rate from this eruption was 700 tonnes/day on March 9. Detailed information is available on the USGS Hawaiian Volcano Observatory WWW site.

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