Question 1
Oceanic lithosphere subducts (sinks into the asthenosphere) because ________.
◦ the upwelling magma at divergent boundaries pushes the lithospheric plate into the asthenosphere
◦ old oceanic lithosphere is more dense that the asthenosphere
◦ the pressure from two plates colliding forces one plate into the asthenosphere
◦ the convection of the mantle pulls the lithosphere into the asthenosphere
Question 2
Mount St. Helens and the other Cascade volcanoes are ________.
◦ a row of young, active, shield volcanoes built as western North America moved over a hot spot deep in the mantle
◦ young, active stratovolcanoes built on a continental margin above a sinking slab of oceanic lithosphere
◦ old, deeply eroded stratovolcanoes built before the Pacific Ocean existed
◦ old, deeply eroded, basaltic shield volcanoes built when western North America was over the present-day site of the Hawaiian hot spot
Major steps in the coagulation cascade
Shield Volcanoes of the Big Island of Hawaii
After the Eruption of Mount St. Helens in 1980
Cascade of regulated splicing that controls sex determination in Drosophila embr
Mount Pinatubo caused ~1˚C cooling for up to 5 years
Types of Volcanoes