Volcanism of the Mount Edziza volcanic complex in British Columbia, Canada, spans more than 7 million years. The first magmatic cycle took place between 7.5 and 6 million years ago and is represented by the Raspberry, Little Iskut and Armadillo geological formations. Volcanism has taken place during five cycles of magmatic activity, each producing less volcanic material than the previous one. During these cycles volcanism has created several types of volcanoes, including cinder cones, stratovolcanoes, subglacial volcanoes, shield volcanoes and lava domes. The roughly 1,000-square-kilometre (400-square-mile) volcanic plateau of the MEVC originated from the successive eruptions of highly mobile lava flows. Several types of volcanic rocks were deposited by multiple eruptions of the MEVC. At least 10 distinct flows of obsidian were produced by volcanism of the MEVC, some of which were exploited by indigenous peoples in prehistoric times to make tools and weapons.
Read more: https://en.wikipedia.org/wiki/Volcanism_of_the_Mount_Edziza_volcanic_complex
_______________________________ Today's selected anniversaries:
1953:
Nine Moscow doctors were accused of a plot to poison members of the Soviet political and military leadership. https://en.wikipedia.org/wiki/Doctors%27_plot
1968:
American singer Johnny Cash recorded his landmark album At Folsom Prison live at Folsom State Prison in California. https://en.wikipedia.org/wiki/At_Folsom_Prison
1972:
Ghanaian military officer Ignatius Kutu Acheampong led a coup to overthrow Prime Minister Kofi Abrefa Busia and President Edward Akufo-Addo. https://en.wikipedia.org/wiki/Ignatius_Kutu_Acheampong
2000:
Steve Ballmer replaced Bill Gates as the chief executive officer of Microsoft. https://en.wikipedia.org/wiki/Steve_Ballmer
_____________________________ Wiktionary's word of the day:
bumper crop: (idiomatic) An excess of something; a large yield. https://en.wiktionary.org/wiki/bumper_crop
___________________________ Wikiquote quote of the day:
And as she lookt about, she did behold, How over that same dore was likewise writ, Be bold, be bold, and every where Be bold, That much she muz'd, yet could not construe it By any ridling skill, or commune wit. At last she spyde at that same roomes upper end, Another yron dore, on which was writ, Be not too bold. --Edmund Spenser https://en.wikiquote.org/wiki/Edmund_Spenser