Strombolian EruptionsActivity at Anak Krakatau in November 2007 was characterized by minor, but ash-rich strombolian eruptions ocurring every one to three minutes, and occasionally longer periods with no eruptive activity after which more powerful vulcanian explosions happened (which are covered on other pages). |
 At dusk an ash-rich eruption fills the active vent with ash and incandescent bombs. The summit crater is on the right |  A few moments later bombs roll down the cone's southern slope kicking up a lot of dust. Meanwhile the ash column rises. |  Often lightning occurs within the ash column caused by turbulence and frictional effects between ash particles. |  The ash column rises and creates a lot of turbulence. Bombs only become visible once they come out of the dense ash cloud. |
 Sometimes the ash column reaches high atmospheric layers, where winds take different directions. |  This zoom on the active vent shows details of its interior. Fumaroles are visible in the summit crater (top). |  In the evening of 22nd November, fresh magma is rising within the conduit. The spectacular eruptions reminding us of Etna. |  Sometimes the incandescent bombs are bright enough to cause remarkable reflections in the calm sea. |
 The ash column rises several kilometers into the sky, higher than the cumulus clouds. |  Fishermen observe the "volcanic fireworks" as very fresh magma explodes inside the vent. |  On other evenings, the magma is less hot. Therefore the bombs are of a dull red color. |  Thunderstorms over Sumatra, far to northwest (note lightning on the left). |
Photos by Marco Fulle, taken from Rakata Island from 21 to 24 Nov 2007, about 5 km SSE of Anak Krakatau. Photos taken with 28mm, 50mm, 135mm and 300mm lenses and digicam (to be multiplied by 1.5 to obtain the equivalent focal length on 24x36 film). |