A team of geologists and geophysicists have imaged the path of a Pacific Northwest volcano's molten rock, from the subducting slab to the upper crust. [more inside]
The Vestmannaeyjar Archipelago, off the south coast of Iceland, was first settled in 874 AD. Heimaey, the only populated island, was home to both a center of the Icelandic fishing industry, and a volcano which had never erupted during nearly a millennium of continuous human settlement. Then, in 1973, all hell broke loose. [more inside]
In 1831, the Mediterranean south of Sicily began to boil and bubble, and before long a volcanic island appeared, in full eruption. The English were the first to lay claim to the new island, naming it Graham Island, for James Graham, First Lord of the Admiralty. Then the Kingdom of the Two Sicilies laid claim to the island, removing the Union Jack and naming the island Ferdinandea, after King Ferdinand II. The next nation to claim the island was France, though initial French interest was in the geology of the newly emerged island (Google translation of French text, much from geologist Constant Prévost). France's choice of names was practical, Île Julia, as the island was formed in July. Spain also tried to lay claim to the newly formed island, setting the stage for a grand four-way dispute over its sovereignty, but before a single shot could be fired over its possession, geology rapidly had the last word on the matter. Graham Island/ Ferdinandea/ Île Julia crumbled in on itself and all but disappeared by the end of the year. [more inside]
New electrical conductivity measurements show the subterranean extent of the Yellowstone supervolcano to be a lot larger than previously known.
Oh cool, a thermal video of a Hawaiian volcano. More cool, but non thermal, video of another volcano in Hawaii. Another awesome geographical happening in you know where. Wow, the place is a hotspot for shield volcanoes, even has its own observatory.
How does an ecosystem rebound from catastrophe? Thirty years after the blast, Mount St. Helens is reborn again. Interactive Graphic: Blast Zone. Also see National Geographic's feature article from 1981, chronicling that year's eruption. Previously on MeFi [more inside]
After months of pre-eruptive activity, Alaska's Mount Redoubt has erupted 6 times since Sunday night. Telegraphing its eruption with massive shallow earthquake activity in the range of 26 earthquakes every 10 minutes, the volcano, located around 100 miles southwest of Anchorage, spewed an ash column 10km high, and is expected to continue erupting for weeks or months. The last time this massive volcano erupted in 1989 a commercial airliner was caught in the ash column, causing the engines to seize and the plane to lose two miles of altitude before the engines were restarted. That eruption, which lasted for 5 months, produced this spectacular photo. Follow this amazing event at the Alaska Volcano Observatory. [more inside]
Cool video of an undersea volcano erupting off Tonga. Spectacular clouds began spewing out of the sea on Monday about 10km from the southwest coast off the main island of Tongatapu, where up to 36 undersea volcanoes are clustered. More on these volcanism blogs.
On June 8, 1783, the volcano Laki in south Iceland tore open a 16-mile fissure that erupted over nine cubic miles of lava. Not only would this eruption kill over 50% of Iceland's livestock population, leading to famine which killed approximately 25% of the population; its effects were felt the world over, with flourine, sulfur dioxide, ash, sand and drastically cooled tempertaures from the blotted-out sun reaching as far afield as North America and Africa. The eruption lasted for nearly eight months. And from the day the eruption began, a humble priest named Jón Steingrímsson would make his mark in history. [more inside]
An erupting stratovolcano poses numerous hazards for nearby habitation, but none nearly so terrifying and deadly as the pyroclastic flow. Pyroclastic flows, comprised of tons of superheated sulfuric gases, particulate rock materials and ash, can reach temperatures of 1,830 °F and travel at alarming speeds up to 450mph. Convection of materials within the clouds causes them to become a suspension, fluidizing and thundering noxiously across the surrounding landscape for miles, in some cases even uphill or across open water. Wherever these clouds come in contact with humans the result is catastrophe, as the residents of Herculaneum and St. Pierre, Martinique learned within minutes of the eruptions of Vesuvius in 79AD and Pelee in 1902-- both towns were overwhelmed by pyroclastic clouds, igniting all flammable materials and incinerating and suffocating the inhabitants. None survived Herculaneum, while just two of St. Pierre's 26,000 survived, one of whom was a prisoner condemned to death and awaiting his execution in a dungeon cell. Despite their incredible capacity for violence, pyroclastic flows are also capable of producing mesmerizing, awe-inspiring beauty.
Surtsey was first observed on November 14, 1963, as a pillar of smoke on the water some ways south of Iceland. The very next day lava and tephra broke the surface of the Atlantic and by May, 1964 the formation had grown to 2.4 km². Over the next three years lava eruptions continued, coating the loose debris in a hard shell and protecting it from erosion. An island born. Naturally, Surtsey has been under close scientific observation since its emergence, and courtesy The Surtsey Research Society you can read published reports on the geology and biological colonization of this new earth.
British diplomat William Hamilton (whose 2nd wife Emma is perhaps best known for having a scandalous public affair with Horatio Nelson) loved volcanoes. His 1776 book Campi Flegrei: Observations on the volcanoes of the two Sicilies* used stunning hand-coloured illustrations by Peter Fabris to demonstrate to the scientific world that volcanic processes can be beautifully creative as well as horribly destructive. [via this post at the nonist, which, in case you hadn't noticed, has been really great lately] [more inside]
Mount St. Helens Erupting.
Anybody have any money riding on this?
Anybody have any money riding on this?
Can we predict volcanic eruptions? PBS aired a NOVA program called "Deadly Shadow of Vesuvius" in 1998 which suggests that we can by monitoring small scale earthquakes which "swarm" as an eruption approaches. Why is this important now? Look at this map, which indicates the occurence of over 40 earthquakes under Mount St. Helens just today, with 10 being over 3.0 on the Richter scale. The Pacific Northwest Seismograph Network has issued a series of alerts with more detail. National Geographic is reporting that an eruption is imminent.