Lesson 17: Accreted Terranes and Landslides This is our final
lesson and, perhaps fittingly, it considers our most exotic
parklands. This week we'll explore accreted terranes: blocks of
lithosphere foreign to North America that have been added to the
continent along its convergent or transform margins. As Lillie
points out, we've encountered accreted terranes before—in the
Appalachians, for example—but this week we'll explore parks in
Alaska and Washington state that are new to us and exemplify
this style of continental growth. Because landscapes built by
terrane accretion almost alway involve high mountains cut by
numerous faults they are often subject to landslides, so our
last exercise will focus on assessing landslide hazards. This is
also our last regular week of class, and next week we'll have
our final. I will post an announcement with more information
about the exam on our course's Etudes home page shortly. It will
be very similar to the quizzes we have been doing throughout the
semester, however, so