The Heat from Within: Earthly insights into planetary volcanism

The Heat from Within Teacher Training Workshop


To "Galapagos Volcanos - 2"

On the workshop, we could only see volcanos in a portion of Oregon, which is unusual in having so many different kinds of volcanos together, and in being at the boundaries of so many geological/tectonic areas. So, the skeptic might ask "Are these volcanos representative of the Earth and other planets, or just weird and peculiar to this spot?" Fortunately, most of the features we saw are representative, and here is evidence!

Ocean islands, like the Galapagos, represent a geologic environment far different from any we saw in Oregon, but which still have basalt volcanos. My sister, Evelyn Treiman, visited the Galapagos Islands earlier this year with a tour from the New Mexico Museum of Natural History. She took lots of photos of wildlife and geology, and agreed to share these with our Workshop. Credit.

Red Cone
not a'a

Cinder Cones. Here, at dawn, are a field of cinder cones, with steep slopes and flattened tops showing that they have a small crater on top. Compare these to Lava Butte near Bend and Wizard Island inside of the Crater Lake caldera! Sullivan Bay and Santiago from Bartolome Island. Credit.

Basalt Flow. The lava flows on the Galapagos are all basalt - dark fluid lavas like we saw at Rich's flow. In this view are slabby and a'a like tops. The little cones on the flow are a common features we did not see on the Workshop - rootless spatter cones or 'hornitos'. Bartolome Island. Credit.
Red Cone
not a'a

Shield Volcano 1. To compare with what we saw in Oregon, note the shallow slopes of this shield volcano, the flattish top suggesting the possiblity of a caldera, and the many cinder cones on its flanks. From Santiago, Bartolome Island. Credit.

Shield Volcano 2. Another shield volcano, lower and with many more cinder cones on it. Why would one shield volcano be steeper than another? Why would one have more cinder cones than another? Santa Cruz Island. Credit.
Red Cone
not a'a

Tuff Ring. This is Daphne Major island, a tuff ring volcano like Fort Rock. Daphne Major has the classic ring-shaped hill with a broad crater inside. Fort Rock probably looked like this soon after it erupted. Credit. Daphne Major is famous in evolutionary biology for its finches. Peter and Rosemary Grant have studied the finches for decades, and documented their geneaology and how their populations have responded to weather and climate. You should read their story in "The Beak of the Finch" by Jonathan Weiner.

Old Tuff Cone. This is Daphne Minor island, which was also a basalt eruption into water (the ocean). With its steep, wave-cut cliffs, this is probably how Fort Rock appeared before the lakes dried up. The birds are Audubon's shearwaters. Credit.

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Copyright Allan Treiman, LPI.
Updated 07/28/06.
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