I’ve just run into brief reports about a new “eruption” in Colombia – but not the normal kind of eruption. Now, the one of the articles in English that I have found describes the 25 injuries as a result of people trying to “escape the lava.” However, it is pretty clear in other reports that this was a “mud volcano” rather than a magmatic one. The location of supposed eruption (spanish) is 40 km the town Arboletes in northwest Colombia, which is not a volcanically active area – but some of the reports describe the eruption as a “mud volcano” (spanish) that was preceded by a “large flame”. The pictures associated with the “eruption” (spanish; see below) also indicate that is was a “mud volcano”, so any report that people were outrunning lava is clearly erroneous. This is, in fact, the second time an event like this has happened near Arboletes.
Mud volcanoes are very similar in their dynamics to eruptions of low viscosity lava – you can read a good description of how they work here. Wet sediment can get trapped in the strata, where pressure can build until that “mud” finds a path to the surface. Natural gas is common with other mud volcanoes, so the report of a flame associated with the “eruption” is not too surprising. The most famous recent mud volcano is in Lusi in Indonesia – and was likely triggered by manmade drilling in the area.
UPDATE: I’m just adding this short article because they have the gall to put a picture of the 1991 eruption of Pinatubo to illustrate this mud volcano. Wow.
Top left: Mud from the October 19 “mud volcano” in Arboletes, Colombia.