• Theme of the Week
• What you will accomplish
• How you will do it

Themes of the Week:

This week's themes focus on accreted terranes and continental growth, including how much of the Pacific Northwest has been added to the continent by the accretion of exotic terranes.

To fully explore these themes you will:

• Choose a term project field site, or descirbe several possible sites and prepare to choose one by Week 6.
• Define exactly what contstitutes an accreted terrane.
• Apply the definition of accreted terranes in making a case for a given body of rocks as being an accreted terrane.
• Develop a picture in your mind of how accreted terranes have been added to the Pacific Northwest.
• Describe several types of evidence that indicate a terrane is exotic.
• Explain how terranes can be moved from far away by plate tectonics.
• Describe how a terrane can be accreted to another plate from a subducting oceanic plate.
• Describe the evidence which indicates that some Pacific Northwest terranes have been brought far north from where they formed, and some have been rotated.
• Explain why terrane accretion did not start occurring in the Pacific Northwest until the Jurassic Period.
• Label the sequence of rock types in an ophiolite, explain how each rock type of an ophiolite forms in oceanic lithosphere, and describe how ophiolites are important as accreted terranes.
• Describe and distinguish the Intermontane Superterrane from the Insular Superterrane.
• Describe how the Omineca Belt and the North Cascades Crystalline Core are related to the Intermontane Superterrane and Insular Superterrane.
• Relate the Olympic Mountains to accreted terranes.
• Organize a list of named accreted terranes in terms of what type(s) of crust they are made of, when in geologic time they accreted to North America, and which superterrane they are part of.

By completing the following:

1. Prepare your Term Project Plan. See the Term Project Plan Instructions.
2. Check that your term project plan meets the standards outlined in the Term Project Plan Rubric. After making any necessary revisions to your plan, post it in the Term Project Plan folder.
3. Read Lecture 5-PNW accretionary tectonic history and its linked Basics and Focus pages and refer to them in your assignments.
4. Participate in the Week 5 Discussion, in which, among other topics, you post a message telling the rest of us the location of your term project field site and why you think it is a suitable site for a term project. See Weekly Discussion Rubric.
5. Read Week 5 Lab Assignment. Complete Lab Assignment #5 by:
   1. submitting the Lab #5 answer form in the online classroom
   See Lab Rubric
6. Take Quiz #5 in the online classroom. See the Weekly Quiz Rubric.
7. At the end of the week, compose a summary of the main things you learned about the geology of the Pacific Northwest and post it in the online classroom Week 5 Summary. See the Weekly Summary Rubric.

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