Are Exceptionally Violent Volcanic Eruptions More Common Than We Think? Part 2 of 2

Landsat image of Lake Taupo on New Zealand North Island.  Image courtesy NASA Landsat, 2005 via Wiki

Advertisement

Are Exceptionally Violent Volcanic Eruptions More Common Than We Think? Part 1 of 2

Follow-on Hunga-Tonga eruption on Jan 16.  Image courtesy Tonga Geological Services via teleSUR, Jan 17

The Nitrogen Geysers of Triton

Annotated Voyager 2 photo of active nitrogen geysers on Triton. Photo taken on Voyager 2 1989 flyby of Neptune and Triton. Photo courtesy NASA JPL via Nitrogen Gas blog, 2017

Introduction to Volcanic activity on Mercury

Perspective view looking NW over the Caloris Basin. Pantheon Fossae, radial dike swarm in the foreground. The Impact crater just offset to the right of the swarm is 41 km in diameter. Red and white are higher topography; blues are lower. Total vertical difference is 4 km. Image courtesy NASA/Johns Hopkins University Applied Physics Laboratory (JHU / APL) / Carnegie Institution of Washington/Goddard Space Flight Center

Manda-Inakir, Rifting Volcanism in the Afar

Manda – Inakir recent volcanism. The Kammourta volcano is flagged at the red pointer. It is the 1928 – 1929 most recent eruption from this system. Multiple lava flows at center to the south of the main line of lava flows is the Dabbahu Manda Hararo rifting event of 2005 – 2010. The Andabba plain is to the lower right of the image. Google Maps screen capture.

TUFF.. TUFA?.. IGNIMBRITE – Pyroclastic Deposits

Erosional structures at Göreme, central Cappadocia Region. The tuff is thought to have been deposited by the Mount Erciyes eruption ~2.6 ma, covering an area of about 20,000 km². This was the last of the series of great Cappadocian ignimbrites. (© Claude Valette, via Wikimedia)

In many descriptions of volcanoes and their eruption histories we stumble upon the terms Tuff, Tufa or Ignimbrite. Most every self-respecting volcano has one or all of them. Generally it becomes obvious from the context that they refer to widespread deposits of volcanic materials. But what exactly is an ignimbrite?, is it different to tuff?, and where do they all come from?

Tuff and ignimbrite are clastic rocks composed of volcanic

What is an Intraplate Earthquake?

Schematic of location of Nov 30 Anchorage earthquake. Image courtesy Temblor.net

 

Intro:  I wrote this some 12 months ago, a couple months after our M7.1 intraplate earthquake here in Anchorage.  This seems a good time to revisit what happened and why.  As usual, there are more questions afterwards than before.  Cheers –

Volcanoes of Io – Part 2 – The Volcanoes

Galileo 1998 image of Io. This one shows two active plumes. Pillan Patera plume is at the upper limb of the moon. It is 140 km tall. Second active plume is Prometheus Patera center bottom near the terminator between dark and light

Volcanoes of Io – Part 1 – Introduction

Io. Orange is plume deposit around Pele Patera. Multiple patera and plains are visible. Note lack of impact craters meaning the moon is regularly resurfaced. Image courtesy NASA JPL via Sen.com

Lago Ilopango – an El Salvador Caldera (updated and reposted)

Ilopango Caldera

 

Update, Aug. 2019:

In the five years since this was first posted, science continues to grind away, answering a few questions which in turn create a bunch more questions.  The Baillie tree ring / ice core team is increasingly of the opinion that the 535 – 540 AD global cooldown was caused by huge volcanic eruptions, at least two of them bracketing the period.  A team including Robert A Dull published a paper August 16 entitled “Radiocarbon and geologic evidence reveal ilopango volcano as the source of the colossal ‘mystery’ eruption of 539/40 CE” that appears to nicely define the most recent end of that bracket.