Central Madagascar Volcanic Fields

Central Madagascar volcanic field. Note multiple cinder cones in the field. Image courtesy WUSTL, 2016

Dotsero Volcanic Complex, Colorado, USA

Remaining maar of Dotsero volcanic complex.  Image courtesy Our Community Nov, 2019

Dotsero is the most recent of four quaternary volcanic centers in NW Colorado.  The locations and relative ages are: Dotsero (4,150 years ago), Willow Peak (undated), McCoy (0.64 Ma) and Triangle Peak (1.98 – 1.87 Ma).  Triangle Peak was the only one of these not monogenetic as it produced at least 11 lava flows before activity stopped.  Willow Peak is described as a young cinder cone with a narrow lava flow extending 6 – 7 km E.

Volcanoes where we don’t expect them – GARROTXA VOLCANIC FIELD, NE Spain

Castellfollit de la Roca: The confluence of the rivers Fluvià and Toronell created this stunning geological monument between them: a 1 km long and 50 m high basaltic lava crag, consisting of two superimposed lava flows with columnar jointing. (© Nasobema lyricum 2006, via Wikimedia)

View to the north over the northern part of Garrotxa VF, with the town of Olot in the left middleground. In the background the snow covered Pyrenees can be seen. (© turismegarrotxa.com)

Today our fancy takes us to the NE of Spain. Just to the corner where the Pyrenees mountain range meets the Mediterranean Sea, to the province of Girona in Catalonia. For millions of us European tourists the Mediterranean Costa Brava with its golden beaches is a household name. As in so many other touristic spots in the world, one could ask, how many of the sun worshippers would have known that, some 60 km inland, there is a volcanic field to be visited?

Australia 4 – The Volcanoes of Victoria and Tasmania

Schematic of volcanic provinces in Victoria. Older volcanics are depicted in green, Newer in orange, and Macedon – Trentham in blue. Image courtesy Meeuws, et al. https://www.sciencedirect.com/science/article/pii/S0264817216300605

 

This post will cover remaining volcanic activity in southern Australia.  The majority of it is in the southeastern state of Victoria.  The most recent activity has spilled over the border to the west into South Australia.  Finally, we will take a look at volcanic activity in the Bass Strait, the water separating Tasmania from the rest of the continent and a quick look at volcanic activity in Tasmania.

The Ugashik – Peulik Volcanic Center, Alaska

Mount Peulik with the Ukinrek Maars in the foreground. Phot courtesy Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Aerial_view_of_mountain_Peulik_ukinrek_maars.jpg

Recent Volcanic Activity in Nevada, USA – Part 2

Mud Springs volcano, Aurora – Bodie volcanic field. Lava flow is andesitic. Photo courtesy NASA Earth Observatory. https://earthobservatory.nasa.gov/IOTD/view.php?id=50493

Recent Volcanic Activity in Nevada, USA – Part 1

Lunar Crater Volcanic Field from the air.  Lunar Crater itself is a maar.  Photo courtesy Hindred Settling Blog.  https://zsylvester.blogspot.com/2009/12/lunar-crater-volcanic-field-nevada.html

The Michoacán – Guanajuato Volcanic Field, Mexico

Paricutin volcano, lava flow and buried church. http://www.amusingplanet.com/2014/08/paricutin-volcano-that-grew-out-of.html

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.