1. The Earth presented by Prof. Geller 29 October 2002
HNRS 227 Lecture #18 Chapter 19
The Earth
presented by Prof. Geller
29 October 2002

2. Key Points of Chapter 19 Minerals Rocks The Rock Cycle
Igneous, Sedimentary, Metamorphic
The Rock Cycle
Earth’s Interior
Crust, Mantle, Outer Core, Inner Core
Plate Tectonics

3. Telling Rocks Apart
How geologists tell apart different minerals and rocks
color, luster, texture
hardness test
scratching one against another
diamond is hardest
acid test
using weak hydrochloric acid to
streak test
form a streak across a ceramic tile

4. Minerals (see Table 19.1) Characteristics
naturally occurring
inorganic
definite crystalline structure
The natural resources of industry

5. “Rocks formed from hot molten mass of melted rock material”
Igneous Rocks
“Rocks formed from hot molten mass of melted rock material”
See Figure in textbook

6. Sedimentary Rocks
“Rocks formed from particles or dissolved materials from previously existing rocks.”
See Table 19.2 in textbook

7. Metamorphic Rocks
“Previously existing rocks that have been changed by heat, pressure, or hot solutions into a distinctly different rock.”
See Figure in textbook

8. The Rock Cycle

9. Earth’s Interior and How We Know It

10. Earthquakes Galore

11. Earth’s Inside Story

12. Crustal Rumblings

13. Plate Tectonics
“The theory that the Earth’s crust is made of rigid plates that float on the asthenosphere.”
Consider the scientific evidence for plate tectonics and what forced scientists to accept the theory as fact

14. Fossils across an ocean

15. Boundaries Galore

16. Plates are smashing