Oldoinyo Lengai expedition II

27. June - 7. Juli 2004

in deutsch


Organisation by Fred Belton, report of Th. Boeckel, Martin Rietze

Cinema    Cinema


Day 1:
Arusha – Lake Natron – Lengai

A d
usty affair. As a pre taste for the Ol
doinyo Lengai camp we could feel the pure fine dust which was creeping through every little chink.


Protective wall: Each settlement is surrounded with a solid wood barricade which should keep away wild quadruped, tourist etc..... Like Martin needs to say: The human beeing in this region of the world does not belong to the end of the food chain. In this landscape it is amazing under which hard conditions the Masai people can survive.

Day 2:
Lake Natron


 The  Lengai with the typical wild life and morning impressions on the 'Mountain of god'


The Lake Natron with its magnificent bird world

Day 3: The Ascent


To evade the hot temperatures the ascent of the expedition was started around 1 o'clock at night. Beside our luggage, 35 porters transported in stages 250 litres water, meals for twelve persons for eight days up to the 2835 m level of the north crater. The summit height of this volcano is about 2955 m. While concentrating to balance the cameras and the other optics over the steep and rocky slopes the Masais were ascending like gazelles. Additionally an extreme cold and strong storm was treating us badly. Inside the crater plateau pieces of loosen lava were taken up from the storm and facial collisions has been very painful. Together with the cement-like dust in the crater camp it was nearly impossible to film or taking photos. Nice to imagine if that weather disaster would have continued the next eight days. Nothing as dust before the camera... plus small scratches on the films.The pictures shows the Masai porter after our arrival at the summit. The dark atmosphere resulted from the strong sandstorm. Here we met also the Chris Weber group which observed the volcanic activities already five days before.


The always changing landscape of the northern crater plateau. The lava flows expanded during one week over the south and north east part.

The map is based on the GPS measurements of
Chris Weber. The link to the site (V.E.I.) is at the end of this page


The T58 Cones from the afternoon into the night

Lengai and astronomy


The southern Milky Way and the Zodiacal light * (Wide angle, 20 mm )

Night photos of the cones. This fantastic scenery acquires the digital exposure technology. In case of the long exposure times, the red incandescence walls of the main cone did become effective on the chip. For the human eye the reflection at the white cone walls of the weak shining lava lake was hard to discover.

* Zodiacal light. Illuminated space dust which is concentrated in the ecliptic layer of our solar system. Every body or planet belonging to our system leaves a little track of material (dirt) while orbiting around the sun. In equatorial areas this light pyramid is standing nearly vertical. Straight on waking up from my midday nap the first activity already announced itself. The T58 C cone broke laterally and up to 10 meter high ejections were catapulted out from the hole. For the first time I saw this strange lava mass silvery shining in the sun.


This highly liquid lava which changes immediately into the AA lava consists mainly of Natriumcarbonate (Soda).During the observation I saw one detail that this lava at the south cone had pearl-like components and already with the exit a minimum roll effect was resulting from this partial viscosity. This strange behaviour of currency which differs also acoustically from the silicate lava was moving very rapidly, and you must react very fast to evade larger lava quantities during an eruption.

The temperature measurement of the Chris Weber group some days before was about 560 C°

Day 4: Collapse of the bridge


The activities were still going on through the night. At the same time a loud lava lake made itself attentive in the main cone T56 B, which was observed from us standing on a lava bridge. There was only one big problem. Assuming by us falsely, this bridge should have be of a good static condition.

On the photo you can see us standing on the bridge. Right: The first setting cracks of the weakened nature building already start s to get bigger.

To create the general tendency more precarious in our group - take the lava bridge inside the cone T56 B and step on it around 19:30, to recognise afterwards that this plateau was broken down half an hour later – completely!!!

To our surprise no base pillar exists under this bridge and after the breakdown the wild raving lava lake with a supposed diameter of 15 meters was offered to us. If someone would have been on this natural cantilevered construction we would have had a dead- surely barbecue at this time. Now it is also understandable why Fred Belton was running after this discovery extremely nervously to the camp to count every one. Nearly coming in trouble, I have to mention Olivier and Fabian: They did experience this happening more promptly. They stood 15 minutes before the collapse on this dammed bridge.


 Day 5; free view into the lake

However, the collapse of the bridge had the big advantage that we had finally a free view on the lava lake. More respectfully we placed ourselves again at this place and recognised also that the cone wall partly broke down too. The picture from Martin shows the abruptly ending footprints at the edge. Nevertheless a marvellous sight. Standing inside cone the gurgling noise was amplified so strengthened that we did almost had problems understanding our own words. Nice to mention that from the distance (camp) the sound reminded me of a mild sea surf. Together with the full moon a great romantic atmosphere!

The photos from Martin shows the open lava lake after the collapse


Gradually the T58 C comes again active, which means to stay the night awake. Night or 24h watches were our live insurances because in the case of a cone break the time of lava flooding can take less than 10 seconds. Fred Belton, made this bad experience 2002. The complete kitchen (tent) was buried under a huge lava flow.



Day 6:  „Lava is coming to the camp!“

,If you have lava into the kitchen there is no time for bitching!'

This poem from Fred and Jeff has a truthful sense. During the sleeping time this event would have had catastrophal consequences. So you rest in your tent thinking about what to do if the message comes...


 „Lava is coming to the camp!“

Exactly this alarm I mean, and it was the reality. Richard who stood the whole night in connection with Olivier and Fabian by using walky talkys was loudly announcing this volcanic attack. Jumping out of the tent and running like hell I was overwhelmed of the first sight. Two lava streams in precarious speed pushed toward to our tents. However I noticed that the supply from the cone diminished - thus the actual danger was banned. Remarkable was, that in this speed which I ran up to the cones the lava streams lost their glowing luminosity. The flows stopped about 50 m before our tents

Without an announcement the south cone poured over, and in a rapid speed the lava covered completely the steep slope. Stationed on little plateaus the lava flowed around us - in addition you could enjoy still the thermal-visual stereo effect in the centre. This activity repeated itself the whole night and during the day.


Strong activity at the T58 C (South crater)

The south cone over - flow



In an distance of 20 meters nearly all photographers were stationed over the whole night close to the happening. Standing with Olivier a little bit beside of the main track of the lava flush Martin, Fabian, Jeff and Richard selected the direct line of fire

.               mr

The estimated speed of the outgoing lava came over 10 m/sec (video)

Without an announcement...


...the south cone spilt over, and in a rapid speed the lava covered completely the steep slope. Stationed on little plateaus the lava flowed around us - in addition you could enjoy still the thermal-visual stereo effect in the centre. This activity repeated itself the whole night and continued during the next day

The estimated speed of the down flowing lava came over 10 m/sec (video)



A short but impressive sight was before sunrise. During these special lighting conditions the lava got a strawberry - sorbet similar shining colour (T 58 C). Only in these 10 minutes meaningful photographs were possible at all. On this morning another second surprise with our ‘long faces’ took place. During the second night half when we stood all together at the south cone the most beautiful Pahoehoe lava from the T49 B/C cone spilled out on the northern side. Without recognising anything we were astonished on the next morning real badly. Without us much volcanic action was going on at this place…!!!.

Day 7

Inside the centre cone T56B the lava lake was grumbling and the wall of the south cone T58C broke again. This time I stood together with Richard and Fred in the line of fire. An immense mass from the cone flowed suddenly down and so we had to run for our lives. On both sides the lava did already passed beside us and we found out that the yellowbelly transverse foot tactics to the slope was the most successful. May the lava gives you a free space.

In the afternoon time we had the agony of choice. On the north side the ' Pahoehoe - lava ' was flowing again and created a rim - overflow




That means the lava crosses the edge of the crater plateau and the whole mass is spilling down the steep slopes of the Lengai. Like water the lava was flowing out from the small lateral openings of the cone T49 B/C, than disappeared under the white old lava to re-emerge like a spring in a distance of 40 m . This consistency reminded inevitably of oil sources and after the statements of Fabian we should all be stinky-rich now.

The Lengai Red  ......  a new colour


 The flowing lava of the T 49 B in the evening light was excellent photographed by Martin

Day 8;

OK, we survived all these outbreaks without serious problems. The T 56 B remained constant in its strong activity. Up to the next morning we counted 10 violent outbreaks. The strongest occurred before sunrise. The morning dawn let the whole scenery appears in the ideal light.



Over night the lava canalized itself and flowed exactly like in a bob run. This permitted us to approach up to four meters to this hot liquid.


Sulpur drop stones and cristal caves


Minerals on the 3 day old  lava of Lengai were existing  mainly on the gasing  little cracks.

9/10th last day descent,

The coincident was, that with the last morning activity the whole activity was stopped. Thus a nearly unusual volcanic peace occurred in the next night continuing on up to the last day of descent.


Except of Fred Belton,

he observed the volcano three weeks more because for further examinations. He wanted to know if the air pressure stands in connection  to the eruptive behavior. Fred informed us that the activity stopped nearly for two weeks completely but then the T 56 B/C erupted very violent.An east rim-overflow was the consequence. Fred has to move in the South crater because of safety reasons.

All in all it was a great natural experience which showed us the very different facets of Ol Doinyo Lengai. For me it is very important to say, that this strong international expedition group was one beneath the other very peace and helpful. For the excellent organisation Thanks to Fred Belton. Special Thanks tho our cook Paulo, and Richard Roscoe for organising a porter at the fourth day which brought a rucksack full with beer ..... ( Some photos are uc.)

Members Lengai 2004:  Patrick Koster (Holl), Ge Beyers (Holl),  Olivier Gruenwald (Fra) , Fabian (Fra), Jeff Brown (USA), Richard Roscoe( GB/Ger ), Martin Rietze and me.

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Erforschung des Lengai Dipl.-Geol. Frank Möckel

Patrick Kosters Web site, PaKos Photography


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