My Personal Field Trip to the Maar-Diatreme Volcanoes of the Eifel Volcanic Field (DE)

The now beautiful Holzmaar erupted 25 000 years ago. Sediment drill cores from here are used in comparative studies in both the Greenland Ice Sheet and Ice Core projects. (Photo: geopark-vulkaneifel.de)

A maar is a hole in the ground, of volcanic origin… what else?… caused by interaction with water… That was about all I knew about maars when I prepared for this year’s holiday, in the German Eifel maars area (Vulkaneifel, Rheinland-Pfalz district). I did not expect to find a great lot of evidence for former volcanic activity. Probably all covered by sediments or eroded, mined away or grown over – that’s what I thought. Mind you, it was not the famous Laacher See caldera I visited which had produced a VEI 6 eruption some 13 000 years ago.

Antarctica 1 – Introduction to Antarctica’s Volcanoes

Map of Antarctica with locations named. http://historyoftheearthcalendar.blogspot.com/2014/12/december-13-antarctica-freezes.html

Recent Volcanic Activity in Northern Arizona

Lava Flow next to the Colorado River, Grand Canyon. https://answersingenesis.org/blogs/georgia-purdom/2014/06/07/the-grand-canyon-and-my-comfort-zone/

Geothermal exploration at Mount Spurr 2008 – 2011

Summit of Mount Spurr August 2011. Crater lake created in 2004 is frozen over again. Crater is refilling with snow. Fumarole field remains. https://volcano.si.edu/showreport.cfm?doi=10.5479/si.GVP.BGVN201201-313040

BATHOLITH…, LOPOLITH…, SILL OR DIKE? – INTRUSIONS (2)

INTRUSIONS PART 2: INTRUSIVE ROCK FORMATIONS

Elephant Rock (NE Lower Austria) is an outcrop of the South Bohemian Pluton (central Europe). This batholith is one of the largest intrusions within the Variscan (or Hercynian) orogeny, with a surface of ~6000 km². The rounded “elephant” shape of the granite blocks is caused by spheroidal or woolsack weathering. (© Isiwal, via Wikipedia)

GRANITE…, SYENITE…, DOLERITE… INTRUSIONS (1)

INTRUSIONS PART 1:  INTRUSIVE IGNEOUS ROCKS

Stone Mountain is a part of the Spruce Pine plutonic suite in North Carolina, U.S.. Petrologically, “the marginal phases are fine- to medium-grained muscovite-biotite tonalite to granodiorite, and the interior of the pluton is largely medium- to coarse-grained leucocratic muscovite-biotite quartz monzonite to granite”. Not that complicated, or is it? (© Nathan Lyons)

Magma is intruded somewhere deep down, it stays down there, it cools down there, never to be seen for the next couple of million years – why should anybody care about it? Well, as we’ll see, in many places it DID come up. In fact, a good percentage of Earth’s surface is made up of intrusive rocks.

1999 – 2001 Eruption Sequence in the Gakkel Ridge

Gakkel Ridge across the Arctic Ocean basin https://www.researchgate.net/figure/284359093_fig1_Fig-1-The-study-area-is-the-Gakkel-ridge-Dotted-line-divides-the-Gakkel-Ridge-into

A PRECIOUS VOLCANO – KUDRYAVIY (KURIL ISLANDS)

Medvezhia volcanic complex (© kkv1970, via Wikimapia)

Sometimes I browse satellite images on WorldView to see what “my” volcanoes are up to. The other day I noticed a thermal anomaly on “Medvezhia”, Iturup Island, Kuriles. So I went back to look at every day of May and found that a red spot had shown on eight days in May, sometimes two spots, practically on most days the mountain wasn’t covered in thick clouds. Could that be a glowing hot lava dome, degassing, with an eruption to come, or a small one going on already?

Mount Damavand, Iran – The Original Mount Doom?

Mount Damavand http://outdooruae.com/persian-volcanoes-mount-damavand/

Volcano & Verdelho – PICO – Azores Part 5

Aerial view eastwards and into the crater of Mt. Pico, with the cone Piquinho rising another seventy meters. (© Herbert Terra, via Panoramio)

Pico volcano is the youngest in the Azores islands, a kid of just 6000 years. Although it hasn’t been playing with fire in the last few centuries, in a geological time scale he and his siblings have been constantly active during the Holocene. The Island of Pico in the Central Azores group presents 173 square miles of most diverse volcanic landscape – dotted with crater lakes and marshes, with extensive lava fields and caves. It is the most important natural reserve of the Azores. The coast of Pico is dominated by steep slopes with fantastic viewpoints, lava arches and vineyards. Some of the local wines that should be tasted by any visiting volcanoholic are “Magma”, “Basalto” or “Terras d’ Lava” 😉 .