Tag Archives: volcano

Nyamulagira Volcano and Human Evolution

I had mentioned earlier that the volcanoes of the Virugna region in the Western Rift Valley (as well as other highland spots) have often been islands of rain forest separated from each other by different habitats, including grasslands and wooded savannas. this has produced an island effect that has been a laboratory for evolution, and it is likely that these forest islands (and others in the greater region of east Central Africa and western East Africa) have been the loci of evolution of many endemic species. (See Island Africa: The Evolution of Africa’s Rare Animals and Plants by Kingdon for an excellent overview of the Island Effect in highland regions of Central and East Africa.)

It is probably not a coincidence that two of the three subspecies of gorilla live within sight of each other (and of the main subspecies, the lowland gorilla) within this region. The Virunga volcanoes are not old enough to have supported island forests for the evolution of these specific subspecies, but other highlands in the region, or other volcanoes (perhaps in the Eastern Rift) may well have been the location in which they evolved.

And, as it turns out, there is reason to believe that the split between chimps and humans occurred on one of these volcanic mountain tops several million years ago. Or, at least, in an environment geologically similar to the upper reaches of the Virunga Volcanoes. But to tell this story right, I have to go back a few years.
Continue reading Nyamulagira Volcano and Human Evolution

The Volcano Nyamuragira: Some Context

Nyamuragira, just now erupting, is one of the numerous Virunga Volcanoes, which form a large cluster of volcanoes spanning the border of Congo, Rwanda and Uganda, between Lake Ex-Edward (a.k.a. Lake Rutenzege) and Lake Kivu. The largest population center is Goma, on Lake Kivu, along the southern margin of the lava fields from these volcanoes, and made famous in recent years as the site of numerous excursions of warfare, refugee movements, and volcanic lava flows. I’ve written about Goma and a little about the Volcanoes in the Congo Memoirs.

Have a look at the following map:

Continue reading The Volcano Nyamuragira: Some Context

Congo Volcano Erupting

Mount Nyamulagira, 25km (16 miles) from the eastern city of Goma, erupted at dawn on Saturday, sending lava into the surrounding Virunga National Park.

About 40 endangered chimpanzees and other animals live in the area.

But the country’s famous critically endangered mountain gorillas are said to be safe as they live further east.


These are very special chimpanzees. I believe I’ve blogged about them elsewhere, but I’ll write new something about them soon.

I’ve driven though this range of volcanoes, and flown over them as well.

Erik has details here

The Yellowstone Problem

As you have surely heard, the Yellowstone Caldera … the place where Old Faithful and the Geyser Basin reside … has been undergoing increased “activity” including some earthquakes and a rising up of the land. Is this a big problem? Should the evacuate? Should those of us living only a few states away start wearing earplugs?

The paper reporting this, in the current issue of Science, concludes:

The caldera-wide accelerated uplift reported here is interpreted as magmatic recharge of the Yellowstone magma body. Although the geodetic observations and models do not imply an impending volcanic eruption or hydrothermal explosion, they are important evidence of ongoing processes of a large caldera that was produced by a super volcano eruption.

A little vague. I’m pretty sure, from my reading of this paper, that there is not a major imminent danger. But it is interesting to contemplate the magnitude of these things.

This volcano, the volcano we affectionately know as “Yellowstone National Park” (the caldera takes up something like a third of the park area, and is entirely enclosed within it) last erupted in a big way about 600,000 years ago. That was the third in a series of “giant eruptions.” Subsequently, there were several smaller volcanic eruptions, the most recent being about 70,000 years ago.A caldera is a hole left behind when a very large and explosive volcano blows everything out more or less at once. As calderas go, Yellowstone is on the list of the largest known. Here is a rough outline of the Yellowstone Caldera very approximately superimposed over New York City:i-fb1edbc830cdc7f968e24388a0a65d92-NYC_Caldera.jpgHere is a little historical perspective, a list of exenmlar volcanic eruptions of this type (leaving a big caldera, ejecting lots of stuff).

Tambora, Indonesia
192 years ago, a mere 30 or 40 square km in area, ejected about 100 cubic km of stuff.
(About ten other similar sized eruptions have happened during the last 10,000 years, Tambora possibly being the largest.)
Toba, Sumatra
71,000 years ago, about 3,500 square km in area, ejected about 2800 cubic km.
600,000 years ago about 4,000 square km in area, about 1,000 cubic km ejected.
La Garita, Colorado
28,000,000 years ago, about 2,600 square km in area, about 5,000 cubic km ejected (possibly the largest volume of any known volcano)
So, as you can see, the Yellowstone Volcano was a doozie. Comparatively speaking._______________Source:

Chang, W., Smith, RB., Wicks, C. et al.. (2007). Accelerated uplift and magmatic intrusion of the yellowstone caldera, 2004 to 2006.. Science 318, 952-956.