Volcanos of  East- Java, Indonesia

  Semeru, Kelud, Kawah-Ijen, Welirang, Sidoarjo

 6/12/2008 - 6/23/2008, by Martin Rietze 



in deutsch

At the end of our last Krakatau tour (see previous report) we got the information from Alain (Azimuth Travel) over a strong activity of the Semeru with pyroclastic flows. Unfortunately our schedule did not permit an extension, so I decided to fly immediately to the next full moon phase again to Java. Because everybody was busy, I flew this time alone. Beside Semeru, I wanted to visit also the already well known volcanos of this area.

On the trip from Surabaya to the South the artificial mud volcano in Sidoarjo is noticeable. A dam is impounding now the constantly growing mud lake. Numerous houses were buried by this unfortunate drill which caused this fatal outbreak, which obstructed also important highway circuit routes. Shortly before Tretes you pass the Candi Jawi temple.

First the excess of the Welirang stood on the plan. This volcano possesses a very active fumarole field with strong sulphur isolation, which are sometimes hot enough for partial self inflammation. This 3000 meter high mounting from Tretes requires normally an overnight accommodation. Thus, I afforded a jeep and a leader for the first part of the way and for the excess.

This was truly one of my most adventurous area trips, which I ever experienced.

Afterwards I knew why one stands in the back on the car loading area and does not sit down. Also the driver was at any time ready for the jump. So we could found a camp before sunset near the summit.

The first tour shows the large summit crater and the west - lateral sulphur field.



Unfortunately the beautiful weather continued not for a long time. Besides the wind stood in the wrong direction, I had to start numerous attempts to reach the most active sulphur vents. Even the gas mask wasn’t useful by a view of 50cm …

And so the backway without success in pouring rain started in the morning. The west trail was over-grown of vegetation up to the hips, and the rain soaked the underground. This offered me plenty of occasions slipping constantly on the roots and the muddy earth. Despite numerous  crashes, we reached the valley without bone fractures.

The next destination was the volcano Kelud. This volcano is famous of its recurring eruptions, whereby the Crater Lake empties itself and causes lahars. I knew this Crater Lake from 2005. At the end of 2007 a lava dome grew with high speed, but it didn’t come to an outbreak. Nevertheless the complete lake was displaced surprisingly.


You can see these phenomena in comparison on the pictures from 2005 and 2008. In order to examine, whether this dome is still  active after its emerge half a year later, I camped at the crater rim. But not the smallest activity was determined, - only after the thunder storm rain in the evening steam clouds from the still warm inside could be observed.

A long distance drive brought us to the Kawah- Ijen. These phenomena I wanted to reach still before the full moon phase, because I didn’t knew whether the lighting apparition was too weak for the moon light. With the last visit 2005 I did not have the chance to become active at night. During this time, I was informed from this lighting apparition through the pictures published in LAVE.



The local custodian reported from a low sea-level at present and much very hot vents. Because the weather was excellent I still ascended at the same night. On the edge of the crater the blue burning gas flames could be seen despite the high standing moon.

Click for GIF

However not these more-meter-high flames had been spectacularly at all,- instead the burning sulfur which was drawing like lava flows gave the most impression. I haven't seen this aesthetic look anywhere else. Even the Lengai lava would appear boring against it. The burning sulfur rivers shows laminar blue flames like carpet fringes, may fit in comparison with the sun chromosphere. The more airy wind let the flames constantly change the direction in constant sweeps and wave formings. Small red places arose again and again, which took place like micro-strombolian-eruptions in a format of centimetres. Photos can express this in no way, you must see it by yourself.



Surprising for me was the brightness. Dspite the full moon the flame carpets did show an intensive blue colour.

Unfortunately the Kawah Ijen is a mining area for sulfur, which predominantly finds the application for bleaching sugar. Because work is rare in this area, more and more worker chose the cumbersome transport of the sulfur from the crater to the road. I could observe, how even bad quality was mined at present. The people nearly works the whole night thru, and artificial water pools including motor pumps for an efficiency increase are established. The burning sulfur rivers were extinguished by the workers by pouring water with barrels over it still by hand. This prevents sulfur loss by burn-up.


Actually the liquid sulfur is too cool, to burn automatically. However the burning gas torches are dripping down and ignites the liquid sulfur again. How lucky I was to be allowed to see such sulfur fire rivers, I appreciated this in the second night.

More serious workers did completely extinguished all fire places to the beginning of the night. No sulfur fire river could be observed from now. Only the always burning flares gave an interesting contrast. See the size in comparison on the picture with the worker above.

Finally we went to the Semeru. Planning to spend several nights at the Gunung Sawur volcanic observatory proved as impracticable. On the one hand you are not welcome there, therefore I had detailed discussions lasting several hours with the army and the police around midnight. On the other hand this point is photographically very unfavorable, because this point is located exactly in the direction of the sun set, or you have the sun exactly in the back. In any case, from here the volcano seems flat and unattractively. Therefore I changed the position by jeep to reach an optimal place exactly at the south base of the Semeru. Here I spent two nights in the tent.


From there you have the best view, and it is saver than the summit crater edge



Unfortunately the activity had decreased to the normal average, - and no pyroclastics flows could be observed anymore. Nevertheless the weather was good and numerous usually small lightnings in the ash clouds could be seen. With such large, but rare lightnings like on the photos above, beautiful visually impression were offered.


The strombolian activity was partly presented very small, or there was nothing to see. Only in the second night half of the last night several intensiv red ejections arose.




This journey was again very impressive and worthwhile. Unfortunately Semeru and Welirang had been weak active, but the night nature miracle Kawah- Ijen offered far more than I had expected.

More photos in  ALPE, images by M.Rietze



Etna    Stromboli    Volcano world    Cinema

From Etna to Stromboli     Planets & Space

©2008 Photos und Text von M.Rietze (mr),last modification 6.8.2008, transl. and web by Boeckel

This private, non-commercial web site do not use cookies !