Under Construction

Chapters Covered by Exam #3:

In Nesse, Introduction to Mineralogy
• No specific chapters, but you should be familiar with the igneous minerals (certainly those on Bowen's Reaction Series).

In Blatt, Tracy, & Owens Petrology: Igneous, Sedimentary, Metamorphic Chapters 7-10, though some concepts covered in chapters 1-6 will carry over, as well.
• Many of the igneous rock concepts covered by this exam will be "semi-cumulative" from Chapters 1-6 in BT&O.
  For example, the following material is still relevant:
  • What are the three ways to melt the mantle (to form a basaltic magma)? At which type of plate tectonic setting does each of these occur? How do silicate magmas behave differently than water/ice with regard to crystallization/melting behavior?
  • Learn the Big Chart. Live the Big Chart. Love the Big Chart.
  • Illustrate Bowen's Reaction Series with a labeled diagram. Include all relavant minerals and indicate approximate temperatures of crystallization.
  • How are composition, mineralogy, crystallization temperature, density, viscosity, etc. related to each other for igneous rocks/magmas?
  • What is the difference between the normative and modal mineralogy of a rock? Why is each important?
• Know the distinction between alkali basalts and tholeiitic basalts. Understand the basalt tetrahedron. What are the three fields, the two boundaries and the importance of each? What is the importance of norm calculations to this classification scheme? Explain the sequence of early alkali basalts, shield building tholeiitic basalts, and late stage alkali basalts in a hot spot setting such as Hawaii. Is melting or crystallization more important in determining the origin of these two types of magmas? Explain.
• Know the AFM triangle and the origin and significance of the calc-alkaline and tholeiitic trends. What minerals are critical to the early evolution of magmas in each trend? Which trend is associated with which plate tectonic setting and why?
• What is crustal melting? Under what conditions does it occur? Do these magmas form volcanic rocks? Why or why not?
• What is the origin of I-, A-, and S- type granites? In what tectonic setting would you expect to find each? What minerals are characteristic of each type?
• What is the origin of each of the following types of rocks: kimberlites, anorthosites, lamproites, carbonatites? What minerals characterize each of these rock types? What does each rock type indicate in terms of plate tectonic setting? Cite an example of each.
• Draw the cross section of a subduction zone, labeling the important tectonic features. Explain the origin of magmas in this plate tectonic setting. How do magmas in this setting evolve once formed? What types of igneous rocks are likely to be formed when these magmas ultimately crystallize? What sort of volcanoes and volcanic processes are characteristic of this type of plate tectonic setting?
• Essentially the same as the previous question, but for a mid-ocean ridge.