Guatemala's Fuego volcano becoming more active: officials

By AFP | AFP – 20 hours ago

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AFP/AFP/File - Ash billowing from the Fuego volcano is seen from the Palin municipality, Escuintla departament, 40 km south of Guatemala City on February 13, 2015

Guatemala's Fuego volcano is becoming more active, belching out increasing amounts of smoke and ash, officials said on Friday.

Fearing a full-blown eruption of the volcano, located just 50 kilometers (30 miles) from the capital of Guatemala City, disaster officials warned that aircraft should exercise caution when flying over Fuego.

Conred, the national disaster coordination agency, said the volcano's eruptions could range in intensity from weak to moderate, and that columns of ash could reach 4,500 meters (15,000 feet) above sea level.

Authorities also warned that wind-borne ash particles could travel as far as 12 kilometers from the volcano, possibly causing respiratory and other health problems for some Guatemalans.

Fuego, which translates to "fire" in Spanish, measures more than 3,700 meters and is located in southwestern Guatemala on the borders of Chimaltenango, Escuintla and Sacatepequez departments.

Officials said for the moment there is no need to prepare for evacuations, but will continue to monitor the volcano since the situation could change quickly.

Fuego reawakened earlier this year, raining soot and ash on adjacent towns and forcing the temporary closure of a nearby airport.

https://uk.news.yahoo.com/guatemalas-fuego-volcano-becoming-more-active-officials-200542970.html#43qeRTW

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Volcano Watch: Restless activity beneath Mauna Loa continues

Time-lapse multi-image movie of Mokuʻāweoweo Caldera from the Northwest Rim on Mauna Loa. May 7-14, 2015. Images courtesy of USGS/HVO--

video available at source link below

(Volcano Watch is a weekly article written by scientists at the U.S. Geological Survey's Hawaiian Volcano Observatory.)

The recent high lava lake levels at Kīlauea Volcano have caught the attention of visitors and kama'aina alike. But we shouldn't forget that unrest at Mauna Loa continues.

Ongoing inflation in the upper Southwest Rift Zone and summit areas of Mauna Loa suggests that magma continues to rise into the volcano. The current rate and pattern of deformation are similar to the most recent episode of rapid inflation on Mauna Loa in 2004-2005. Earthquakes have also been occurring at elevated rates, particularly around the areas of inflation in the upper Southwest Rift Zone and summit.

Throughout its history, the USGS Hawaiian Volcano Observatory (HVO) has taken advantage of advances in technology to better monitor volcanoes and earthquakes. Computers have become faster, methods of transmitting information have improved, and instrumentation has become smaller and more energy efficient. All these advances have been utilized to create an improved geophysical network that better supports HVO's monitoring and science efforts.

In 2009, the American Recovery and Reinvestment Act (ARRA) enabled a major upgrade to HVO's monitoring networks on Mauna Loa and Kīlauea, including a conversion to digital telemetry, additional monitoring sites, and improved instrumentation. These enhanced networks can now detect earlier stages of unrest, and the resulting data enables more sophisticated analyses of volcanic processes than were previously possible.

Since the two most recent eruptions of Mauna Loa in 1975 and 1984, HVO started using GPS, broadband seismometers, and several types of analyses that were not possible with previous geophysical networks and computers. Certainly, these new data streams and analysis techniques have led to an improved understanding of Mauna Loa and its magma storage system.

Scientists often try to compare previous periods of unrest, such as those in 1975 and 1984, to current unrest to gain perspective on and understanding of what might happen next. With our improved ability to detect smaller and smaller earthquakes and deformation, it is important to keep in mind that signals being recorded now might not have been detectable in past years. This leads to some interesting questions that we're trying to answer.

Were the small earthquakes that we can now record present during previous periods of unrest on Mauna Loa? If so, what was their pattern?

With entirely new techniques available, such as GPS and interferometric radar (InSAR), we can measure the deformation of wide areas on the volcano, which allows us to detect a large, inflating magma reservoir beneath Mauna Loa that previously could not have been detected. But, was this same reservoir active before previous eruptions?

Continuously recording GPS receivers measure episodes of hugely varying rates of inflation interspersed with times of no inflation, which might indicate fluctuations in magma supply to Mauna Loa's shallow storage system. Did these fluctuations occur in the past? The comparison of current and past activity is not as trivial as one might think.

And finally, what will be the outcome of Mauna Loa's current unrest? Scientists cannot be sure at this point.

Seismic unrest is currently much less energetic than it was before the 1975 and 1984 eruptions. Several episodes of increased inflation since 1984 slowed and stopped without eruption. Each of these episodes, however, resulted in greater pressurization of the shallow storage system within Mauna Loa. Unfortunately, we do not yet completely understand exactly how much pressure is involved, or how much internal pressure the overlying rock can bear before it breaks and allows magma to move toward the surface.

Our knowledge and characterization of volcanic systems constantly evolves as improved geophysical networks lead to new scientific discoveries. But before scientists can clearly distinguish between episodes of inflation and elevated earthquake activity that accompany only the intrusion of magma (with no eruption) and those that actually lead to an eruption, there is still much work to be done.

So, HVO scientists continue their diligent efforts to fully understand the processes at work beneath Mauna Loa and to monitor the volcano's restless activity. If any significant changes are observed, HVO will issue public notifications through media releases and our website updates (hvo.wr.usgs.gov/activity/mauna…)

http://www.hawaii247.com/2015/05/14/volcano-watch-restless-activity-beneath-mauna-loa-continues/

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