So what were we up to? The day actually began the day before, organising to borrow a few bits from the kitchen and arranging a packed breakfast instead of lunch.
I thought a little experiment could be fun and interesting. It involved 4 raw eggs and the fumaroles from Day 7.
We left the accommodation at 5.30am, thankfully our driver is a morning person. We arrived at the security gate with sunrise about 30 minutes later and drove to the fumaroles. The contrast between the early morning air temperatures and the fumaroles meant the looked very impressive.
Sunrise over the caldera
Steamy morning. Jenny and myself are in there somewhere.
My field assists carried the basket of supplies and equipment to the fumaroles. Then we spent a little time walking to the sites that were producing more steam to test the heat escaping, selecting two.
My wonderful assists
We put two eggs in to a pan of water that was sat over a fumarole, packing the gaps with bits of lava and grass to reduce how much heat escaped. One egg went in a ceramic bowl with a plate over the top and one egg was simple put in the fumarole just as it is.
Insulating the pan
Another egg all snug in a bowl.
After 25 minutes we took the eggs from the bowl and the fumarole. The one in the bowl didn't quite work. It had began to cook on the outside, but the white and the yolk on the inside were still too runny too eat. The egg that we had just left as it was cooked well, with a slightly runny yolk. The one that didn't work we put on a plate and put it back in to a fumarole. After about 45 minutes we took it out again to find it was almost poached.
Almost poached!
When putting the eggs in to the pan, the shells cracked just a little. After 40 minutes, we took the eggs out, they were certainly hot. But we could tell by gently pushing on the shells where they had cracked that they needed a little longer. So back in to water for about 15 minutes. The water never reached boiling point, but simmered well, so a 5 minute boiled egg was out of the question!
While waiting for the eggs we spent a little more time at the largest fumarole, the steam sometimes making it quite difficult to see and drinking coffee!
It is me, honest! This was the better picture taken. Some, you wouldn't have known it was me.
Wakey wakey!
Back to the eggs! After the extended time in the water, removing the eggs and peeling them, the waiting game was over. Did we have hard boiled eggs???
Hard boiled eggs. Volcano style! And it didn't taste to bad either.
It worked, though it was a long time coming. The success shows that the temperatures of the fumaroles are very high in places. We found that fumaroles that were too hot to leave our hands in on Day 7 were not the hottest today. Shame the temperatures were not high enough today to boil water.
Experiment over. Time to map the fissures.
Mariita (2013), has a very simplistic straight line representing the position responsible for young fissure eruptions. It is rare for a structure of some size to have perfectly straight edges or orientations. I have seen inactive fissures during fieldwork to Mount Etna. They were 'wavy' in plan view but relatively simple, they also increased in depth with elevation. The fissures of Menengai are very complex, very deep and often very difficult to access. The longest fissure we found, we were able to follow for 500 meters before the vegetation and terrain became impossible to tackle.
One of the many fissures
Calculating fissure trends
The lavas that the fissure cuts through could however be traced over a greater distance and the opposite end located. Making this fissure close to kilometre long. It began in the north with a NW-SE trend and curved to have an almost N-S trend. Based on our observations, this is the dominant fissure that is likely to feed the other fissures we found. Other fissures also had trends of NW-SE and N-S, but also NE-SW and WNW-ESE. We have found ten fissures that almost certainly form a network. We are also sure there are many more. But during road construction some have been filled with debris. It was also possible to infer the location of some just by simply observing sections of the road that had begun to collapse in line with or along the same trend as though we were able to clearly observe.
Tomorrow, it is back to road mapping!
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