My notes from the lecture:
The islands are formed by volcanoes in three parallel lines, going from northwest to southeast. The northwest islands are dry, and the southeast islands are wet.
The western islands are the most active regarding volcanic activity. They are newer with less vegetation. They are on two plates: the Nazca plate (moving southeast) and the South American plate (moving west, "crashing" into each other. The Nazca plate is going underneath the S. Amer. plate, called subduction. This is also creating the Andes Mountains.
Galapagos Islands and Hawaiian Islands are similar "hot spot" formations. The plates move, but the hot spots do not, which creates new islands as the plate moves.
Recent Volcanic Activity:
2005, there was an event called Sierra Negra, which was not too explosive with basaltic lava.
2009, Fernandina, La Cumbra volcano.
2015, Wolf volcano on Isabella.
Other terms:
Shield volcano -- flat on top, "soup plate."
Cones are two types: spatter, cinder.
Tuff -- soft material that erodes quickly.
Lava -- Pahoehoe -- rope type, AA -- cannot walk on.
Sand -- white is from organic material, black is from volcanic ashes (on northwestern coasts only, because it is blown there.
Tsunamis have occurred here, but originated far away in Chile or Japan. They need vertical lift or movement to be created.
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