MacDonald, Abbott, and Peterson - Chapter 5, p.135
1. List the name of the igneous intrusive bodies seen in fig. 5.1.
2. Does an intrusive body form by simply filling a crack in the rocks?
3. Explain why intrusive rocks tend to be coarse-grained, whereas extrusive rocks tend to be fine-grained.
4. Explain why many dikes in Hawaii are fine grained.
5. Why are some dikes fine grained in the center, but glassy at the outer edges?
6. How are intrusive bodies classified? (see fig. 5.3)
7. Describe a dike.
8. Give the range in diameters and the average diameter of dikes in Hawaii.
9. Describe a sill.
10. Why are sills in Hawaii likely formed under much greater pressure than dikes?
11. Are dikes or sill more common in Hawaii?
12. Why are laccoliths relatively rare in Hawaii?
13. Which intrusive body is the largest?
14. How large can batholiths be?
15. How many batholiths exist in Hawaii?
16. Are stocks seen in Hawaii?
17. Where do most dikes form in Hawaii?
18. What names are given to areas with numerous dikes? (see fig. 5.3)
19. Give the range of widths for dike complexes in Hawaii.
20. Where are most stocks located in Hawaii?
21. Are dikes common in the caldera?
22. In the central part of the dike complex, what is the average abundance of dikes?
23. Are dikes common outside the rift areas?
24. Are dikes more abundant near the summit of the volcanoes or at greater depths in the volcanoes?
25. Why do dikes tend to indicate local stretching of the crust?
26. How do dikes affect the shape and volume of the islands?