1. Lecture 6 In nature things move violently to their place and quietly in their place. - Francis Bason Intrusive rocks Webpage for course (daytime) Webpage for course (nighttime)

2. Intrusive (plutonic) rocks long cooling time allows crystals to grow larger pluton

3. Pluton: large intrusive igneous rock body can take a variety of shape and sizes tabularmassive

4. Tabular plutons, two general types CONCORDANT D I S C O R D A N T

5. Tabular plutons, two general types CONCORDANT Example: sill D I S C O R D A N T Example: dike

6. Massive plutons, two general types stocks < 100 square km Bathylith (“deep rock”) > 100 square km

7. Associated with modern magma chambers - geysers - hot springs “Old Faithful” Yellowstone N. P. Fig. 10.18

8. “Old Faithful” http://www.nps.gov/archive/yell/tours/livecams/oldfaithful/images/oldfaithfulbehivelabeled.jpg&imgrefurl=http://www.nps.gov/archive/yell/tours/livecams/oldfaithful/oldfaithfulphoto. htm&usg

9. What causes a geyser?

10. Geothermal Energy

11. Inexpensive (after initial cost) Long lasting Low environmental cost Need Shallow Magma chamber DisadvantagesAdvantages

12. Why not use the magma chamber below Old Faithful?

13. “Geothermal Energy” - ground – based heat pumps

14. The metric system! (still have time??)

15. Convenience Accuracy Economy Why metric?