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Lassen Peak erupting on May 22, 1915

The geology of the Lassen volcanic area in the U.S. presents a record of sedimentation and volcanic activity in and around Lassen Volcanic National Park in Northern California. Heat from the subduction of tectonic plates has fed scores of volcanoes over at least the past 30 million years, including those in the Lassen volcanic area. Lava flowed over a lahar-based formation to create the lava plateau that the park sits on. About 600,000 years ago, Mount Tehama started to rise in the park's southwest corner. Roughly 27,000 years ago, a lava dome pushed through Tehama's former flank, becoming Lassen Peak. Phreatic (steam-blast) eruptions, lava flows, and cinder cone formations have persisted into modern times, particularly the formation of Cinder Cone and the 1914 to 1921 eruptions of Lassen Peak (eruption pictured). Since the latter eruptions, the only volcanic activity has been from mud pots and fumaroles. Renewed vigorous volcanic activity could threaten life and property in the area. (Full article...)

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Inna Derusova

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In the news

Hassan Sheikh Mohamud

Hassan Sheikh Mohamud (pictured) is elected as President of Somalia.
In the United States, ten people are killed in a mass shooting at a supermarket in Buffalo, New York.
Ukraine, represented by Kalush Orchestra with the song "Stefania", wins the Eurovision Song Contest.
Mohamed bin Zayed Al Nahyan inherits the Emirate of Abu Dhabi and becomes President of the United Arab Emirates after the death of Khalifa bin Zayed Al Nahyan.

On this day

May 22: International Day for Biological Diversity

Trevi Fountain

1762 – The Trevi Fountain (pictured) in Rome was officially inaugurated by Pope Clement XIII.
1897 – The first Blackwall Tunnel under the River Thames was opened to improve commerce and trade in the East End of London.
1905 – Sultan Abdul Hamid II established the Ullah Millet, a separate millet for Aromanians within the Ottoman Empire.
1972 – The Dominion of Ceylon changed its name to Sri Lanka, adopted a new constitution, and officially became a republic within the Commonwealth.
2002 – Police announced that the skeletal remains of Federal Bureau of Prisons intern Chandra Levy, who had been missing for a year, had been found in Rock Creek Park in Washington, D.C.

T. Boone Pickens (b. 1928)
Lady Gregory (d. 1932)
Myrtle Bachelder (d. 1997)

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Today's featured picture

This is a high-resolution topographic map of the surface of Mars, colored according to elevation, based on research led by Maria Zuber and David Smith on data collected by the Mars Orbiter Laser Altimeter, an instrument on board the NASA space probe Mars Global Surveyor. North is at the top of the main map, accompanied by two insets for the northern and southern polar regions. Highlands (red and orange) dominate the southern hemisphere of Mars, while lowlands (blue) predominate in the north – a feature known as the Martian dichotomy. Notable large surface features visible on the map include Olympus Mons (the highest mountain on Mars) and the volcanoes of Tharsis in the west, the Valles Marineris to the east of Tharsis, and the Hellas basin in the southern hemisphere.

Map credit: NASA/JPL/USGS; edited by WolfmanSF

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