tectonics: volcanoes - case studies and pictures

Volcanoes

The Rift Valley

Chain of spatter cones (foreground) from a linear eruption between Erta Ale and Hayli Gubbi. Note fault scarp parallel and behind the alignment.

Ol Doinyo Lengai

The cone of Lengai (crowned by white lava overflows) stands in the middle of Rift Valley (Rift west scarp on the right).

The typical aa front (about 5cm thick) of a lava flow coming out from the lava lake T49E.

Lengai at Night

Meduse's Hairs born from the lava lake? Volcanologists call them «Intestinal Flows»: they are due to magma differentiation.

Nyiragongo

Erta Ale

Pa Hoe Hoe at Erta Ale

Marco has discovered that Pelee is blonde: Her heir is fair, not black (as in Hawaii), on Erta Ale!

Montserrat

Dallol

When a pond dries out strange salt "bushes" rising from the bottom indicate the former water level.

Dallol Lake

Spectacularly green-coloured ponds below some active salt hornitos.

Sublimation from fumaroles causes salt to deposit in some strange shapes like branches in the wind.

Dozens of hornitos are active within a small area, together creating a symphony of whistles and puffing.

An active hornito ejects water with plenty of minerals which form deposits mimicking a head covered by grey hair.

Krakatoa

Yellowstone

Vulcano

Stromboli

Pamukkale

Pelee