Australian landscapes are ancient, the heady days when rift valleys tore Gondwana apart, and sea floor spreading propelled its fragments around the globe are long gone. It’s hard to imagine a Mt Nyrigongo popping up and obliterating Adelaide. And I do so miss her warmth, the twinkle in her magma and her sweet sulphurous perfume.
But the reality is that western Victoria is littered with volcanoes. It’s just the timing that’s out of kilter.
Ken Grimes, of the Hamilton Field Naturalists Club has written a very nice paper on the subject which you can find <HERE>.
In the Western District there are mainly three types of volcano, though combinations of these also occur. About half of the volcanoes are small steep-sided scoria cones built from frothy lava fragments thrown up by lava fountains. Most of the remainder are broader but flatter lava volcanoes formed from relatively gentle flows of lava welling out of a central crater. A group of about 40 maar craters
near the coast formed from shallow steam-driven explosions which produced broad craters with low rims. These now often contain lakes.
These are the New Volcanics, they started about 5 million years ago. The most recent eruptions occurred about 5000 years ago. They seem to have occurred about every 5000 years so we may be due. According to Ken they erupt for a few weeks or months and never again, the next eruption being at a new site.
Melbourne University’s Professor Joyce anticipates that the next eruption would be “the sort of thing that would be interesting for tourists”. I’m sure it would, and Dr Lin Sutherland of the Australian Museum reassures us that
… no panic is needed. It probably would be a small discharge and a temporary nuisance, rather than the large eruptions we see in the Pacific ‘Rim of Fire’.
This assumes that it isn’t a Phreatic (15 points, more if you can get it on a double or triple word square) eruption. Boil one cubic meter of water and you have 1,600 cubic meters of steam. If magma comes into contact with ground water the result is an explosion. Such
explosions crush the overlying rocks and launch them into the air along with steam, water, ash and magmatic material. The materials usually travel straight up into the air and fall back to Earth to form the tephra deposits that surround the crater.
Thus producing a maar, these are usually a few hundred to a thousand meters in diameter and less than one hundred meters deep. Nothing to panic about.
Tourists do enjoy them but not until they’ve settled down a bit! My favorite is at Tower Hill near Port Fairy, incidentally this vicinity is high on the list for the next eruption.
It’s probably about 25,000 years since it went bang. It is now a very attractive game reserve, home to koalas, emus and kangaroos. Interestingly, you can’t take your dog there but during duck season you can take your gun.
So there you have it … photographic evidence of life on maars.
To say that the Democratic Republic of the Congo has a troubled history is an understatement.
It is a vast country with immense natural resources. It could be wealthy but internal division made worse by instability in neighbouring countries has led to a civil war that has cost the lives, directly or indirectly, of about 6 million people.
The warning signs are obvious, the word Democratic is on the label and if that doesn’t tell you there’s a problem the presence of a UN Peace Keeping Force surely does. And whilst that tells you there’s a problem the UN presence gives no reassurance, their track record is abysmal.
You’d have to be nuts to visit.
Since I’m nuts, why not visit Virunga National Park where 150 Park Rangers have been killed by insurgents in the past decade <National Geographic>. Five more would be killed in combat shortly after I left <defenceWeb>.
And let’s throw in the ascent of an 11,000 ft volcano sometimes called <The most dangerous volcano in the world>. Why so dangerous? Because of the active lava lake, the height of the mountain and the fact that the lava is much less viscous than lava elsewhere. In the 1977 eruption the lava traveled at speeds of up to 60 km/h (40 mi/h) the fastest lava flow ever recorded. Typically lava flows at about walking pace.
In 2002 …
A 13 km fissure opened in the south flank of the volcano, spreading in a few hours from 2800 m to 1550 m elevation and reaching the outskirts of the city of Goma, the provincial capital on the northern shore of Lake Kivu. Lava streamed from three spatter cones at the end of the fissure and flowed in a stream 200 to 1000 m wide and up to 2 m deep through Goma. <Wikipedia>
About 15% of Goma, a city of about 1 million people, was destroyed and has since been rebuilt (about 12 feet higher than previously).
The group assembled at the Virunga National Park office at the foot of the mountain where some old shell cases had been cutely recycled.
There would be twelve tourists, about ten porters and two well armed rangers to reduce the risk that our “agréable ascension” would be to heaven.
Five hours later I was counting 50 steps before allowing myself ten deep breaths. Then fifty more steps. Our accommodation was in sight …
The last few steps were accompanied by a miracle. It was repeated every time a new person arrived. The haggard face of an exhausted mountaineer (we’d earned the title, I’m sure) would turn to wonder, their eyes would light up and an expletive would tumble from their lips.
You could warm your hands on it.
Let’s pull back on the focal length for a wide-angle view into the crater …
The hot spots played across the surface, geysers of hot lava occasionally spewed into the air, the smoke became denser or lighter. If you’ve ever lost yourself in contemplation of a fire it was a fraction of the experience that Nyirongongo’s crucible has to offer.
We dragged ourselves away for our evening meal. It was cooked in pots that had been carried up, on charcoal that had been carried up and eaten off plates etc. And tomorrow everything would be carried down again. The huts and mattresses on the floor was all that stays on the mountain.
After dark it was back to the crater rim to shoot a time lapse …
It was a cold night but the sleeping huts were not as well ventilated as the kitchen hut.