1. The Diversity and Cycle of Rocks

2. Rock Cycle Rock cycle: describes dynamical transformation of rocks between the 3 rock types IGNEOUS, METAMORPHIC, SEDIMENTARY

3. Where are we going? What is the Earth made of? (Of what is the Earth made?) When compounds organize into crystalline structures…. Minerals, otherwise amorphous! Minerals combine to form Rocks

4. Abundance of Elements in the Earth’s Crust 98% of the mass of crustal minerals is from 8 elements

5. Crystals of a Mineral Aragonite - CaCO 3

6. Minerals Mineral: building blocks of rocks Naturally occurring Homogenous Inorganic solid (biominerals okay) Fixed crystalline structure Definable chemical composition Quartz (SiO 2 )

7. Crystal Structure is defined by the ordering of atoms which form a crystal lattice This arrangement produces distinct and and identifying properties of the mineral. -Cleavage -Hardness -Crystal Habit

8. Cleavage

9. Mineral Properties Crystal Form or Habit Cleavage Hardness Color Luster Specific Gravity Streak Other Features Natural Shape Broken Shape Soft or Hard Clear to Colored Metallic or Non- Density=mass/volume Color of powder Reaction with acid

10. Crystal Form or Habit

11. Polymorphs – many shapes Same chemical composition i.e., mineral composed of Carbon Different arrangement of atoms in the crystalline structure C: Diamond versus Graphite CaCO 3 : Aragonite versus Calcite

12. Bonding of Atoms into an Ordered Crystalline Structure

13. Arrangement of Atoms Defines Crystal Properties

14. Valence of the Silicate Ion or Tetrahedron The basic building block of all silicates

17. More Complex Silicate Minerals Pyroxene Amphibole Micas SiO 3 -2 Si 4 O 11 -6 Seriously Complex

18. Tectosilicates – Framework Structure Quartz Feldspars

19. Common Earth Minerals Olivine Pyroxenes Amphiboles Micas Feldspars Quartz Isolated Single Chain Double Chain Sheets Framework

20. Sequence of Crystallization Bowen’s Reaction Series EXTRUSIVEINTRUSIVE

21. Igneous Rocks Igneous rocks: most abundant rock type Formed from freezing of magma at temperatures between about 650-1100 °C Intrusive rocks - Slow cooling within the Earth Extrusive (volcanic) rocks - Erupted on the Surface

23. Addition of Water Results in Partial Melting Formation of Felsic and Intermediate Magmas

24. Igneous Rocks Igneous rocks: classified by mineral size and composition Intrusive rocks -Crystallized slowly -Minerals are larger Extrusive rocks -Crystallized rapidly -Minerals are smaller

25. Granite Rhyolite Obsidian Glass IntrusiveExtrusive IGNEOUS ROCKS – RATE OF COOLING

26. Rocks Types Rock types are categorized by their genesis Igneous rocks: crystallized from (partly) molten material Metamorphic rocks: recrystallized under intense temperature and/or pressure Sedimentary rocks: lithified fragments of pre-existing rock or formed from biological/chemical precipitation Rocks: aggregates of minerals

28. IGNEOUS ROCKS

29. METAMORPHIC ROCKS

30. SEDIMENTARY ROCKS

31. RELATIVE ABUNDANCE OF ROCK TYPES

32. SUMMARY