“Mount St. Helens seized the world’s attention in 1980 when the largest historical landslide on Earth and a powerful explosive eruption reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape.” Quoted from the USGS Fact Sheet titled…. Mount St. Helens, 1980 to Now—What’s Going On?
Research at the University of Southampton determined that the 2010 eruption of Eyjafjallajökull supplied dissolved iron to a large area of the North Atlantic. This stimulated photoplankton growth but the abundance of iron caused the rapid removal of biological nitrate which applied a throttle on the phytoplankton.
“Seismic activity at Pavlof Volcano increased this morning commensurate with the presence of an intense thermal anomaly at the summit observed in latest satellite imagery. Similar patterns of seismicity and elevated surface temperatures have previously signaled the onset of eruptive activity at Pavlof. Although not yet visually confirmed, a low-level eruption of lava has likely begun from a summit vent.” Quoted from the AlaskaVolcano Observatory.
“Forecasting volcanic eruptions with success is heavily dependent on recognizing well-established patterns of pre-eruption unrest in the monitoring data. But in order to develop better monitoring procedures, it is also crucial to understand volcanic eruptions that deviate from these patterns.” Quoted from the Carnegie Institution for Science press release.
You have probably heard of the Richter Scale for measuring earthquakes, the Saffir-Simpson Scale for hurricanes and the Fujita Scale for tornadoes. The Volcanic Explosivity Index is used to compare the size of explosive volcanic eruptions.
“Studying volcanoes can be hazardous work, both for researchers and aircraft. To penetrate such dangerous airspace, unmanned aerial vehicles, especially those with electric engines that ingest little contaminated air, are an emerging and effective way to gather crucial data about volcanic ash and gases.” Quoted from the NASA press release.
“More than 200 million years ago, a massive extinction decimated 76 percent of marine and terrestrial species, marking the end of the Triassic period and the onset of the Jurassic. The event cleared the way for dinosaurs to dominate Earth.” Quoted from the NSF press release.
Pumice is a light-colored, extremely porous, igneous rock that forms during explosive volcanic eruptions. It is used as aggregate in lightweight concrete, as landscaping aggregate and as an abrasive in a variety of industrial and consumer products.
“Mexico’s Popocatépetl Volcano released a plume in early March 2013. On March 8, Volcano Discovery reported an ash plume reaching roughly 1,500 meters (4,900 feet) above the volcano crater, or about 7 kilometers (4 miles) above sea level.” Quoted from the NASA image release.
“A new study led by the University of Colorado Boulder indicates emissions from moderate volcanoes around the world like the Augustine Volcano in Alaska, shown here, can mask some of the effects of global warming.” Quoted from the University of Colorado at Boulder press release.
“Scientists at MIT have proposed that Mercury may have harbored a large, roiling ocean of magma very early in its history, shortly after its formation about 4.5 billion years ago.” Quoted from the MIT press release.
After maintaining a low simmer for ten months, Italy’s Etna volcano boiled over on February 19–20, 2013, with three outbursts in 36 hours. According to the Italian Istituto Nazionale di Geofisica e Vulcanologia, each outburst (paroxysm) featured “emission of lava flows, pyroclastic flows, lahars, and an ash cloud.” Quoted from NASA Earth Observatory.
“Nearly three months after Tolbachik began erupting, lava continues to flow from the Kamchatkan volcano. Over time, the lava flows change location and shift across the landscape. In this image, infrared data is superimposed on a natural-color image to highlight active flows.” Quoted from the Earth Observatory image release.
The Alaska Division of Oil and Gas plans to lease the geothermal rights to Augustine Volcano and 66,000 acres of surrounding land and seafloor. It should be pretty hot since it last erupted in 2006. Results from the lease at Spurr have not been exciting so far.
“The development of a lava dome in the summit crater indicates that sudden explosions of blocks and ash are possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level.
There is no real-time seismic monitoring network on Mount Cleveland and AVO is unable to track activity in real time.” Quoted from the AlaskaVolcano Observatory Alert.
The Volcano Global Risk Identification and Analysis Project has a searchable database of eruptions that you can search using geographic, date and eruption characteristics parameters. Searches produce a map and a data table of eruptions that meet your criteria.
If you have not seen very many sills, then you should visit the Leadville Geology Facebook page. Vince Matthews has posted dozens of photos showing sills in roadcuts, natural outcrops and cross-sections. There’s also a video about how sills form.