2. 2002 Minerals Education Workshop Sponsored by: Indiana Department of Natural Resources – Division of Reclamation November 1-2, 2002

3. www.caingram.com

4. Rocks A rock is an aggregate of one or more minerals. http://people.uncw.edu

5. Rocks 3 Divided into 3 main groups based on origin: 1. Igneous 2. Sedimentary 3. Metamorphic www.travelwest.net

6. Igneous Rocks – Form as a result of cooling & crystallization of magma & lava Indiana Geological Survey

7. Igneous Rocks  Parent rocks for all other rocks  65% of the Earth’s crust  Two major classifications: extrusive and intrusive www.eos.duke.edu

8. Igneous Rocks Classified as either: Crystallize quickly in volcanic eruptions  very small or no crystals www.mineralminers.com 1)Volcanic (extrusive) rocks: www.geo.aau.dk

9. Igneous Rocks 2)Plutonic (intrusive) rocks: Crystallize slowly within the earth that allows crystals to grow Granite www.uct.ac.za www.geocities.com

10. http://kafossils.tripod.com

11. Common Igneous Rocks GraniteDiorite GabbroKimberlite Basalt Pumice Rhyolite Obsidian extrusiveextrusive http://volcanoes.usgs.gov intrusiveintrusive http://cwx.prenhall.com

12.  Identification is based on texture (overall appearance of the rock – size, shape & arrangement of mineral grains) and mineralogical composition Interlocking mineral crystals Identifying Igneous Rocks

13. IGNEOUS Crystalline (interlocking) Modified from Indiana Geological Survey ROCK TEXTURE www.env.duke.edu

14. Texture indicates the rate of cooling Identifying Igneous Rocks Phaneritic texture: coarse-grained; mineral grains are macroscopic www.uct.ac.za

15. Aphanitic texture: fine-grained; mineral grains are microscopic Identifying Igneous Rocks http://volcanoes.usgs.gov

16. Glassy texture Identifying Igneous Rocks www.mineralminers.com

17. Porphyritic texture: contains at least (2) different grain sizes Identifying Igneous Rocks www.uct.ca.za

18. Vesicular texture: numerous cavities Identifying Igneous Rocks http://volcanoes.usgs.gov

19. Pyroclastic Identifying Igneous Rocks http://volcanoes.usgs.gov

20.  Identification is based on texture (overall appearance of the rock – size, shape & arrangement of mineral grains) and Identifying Igneous Rocks mineralogical composition

21. Sedimentary Rocks www.geo.cornell.edu

22. Sedimentary Rocks Form from weathered igneous, sedimentary and/or metamorphic rocks Weathered fragments transported by water, air or ice Can also form from chemical processes http://earthsci.org

23. Sedimentary Rocks Indiana Geological Survey

24. Sedimentary Rocks Indiana Geological Survey

26. Sedimentary Rocks Generally layered or bedded www.geo.cornell.edu

27. Evaporite deposits (white deposits) Indiana Geological Survey

28. Sedimentary Rocks Textures range from very fine grained to coarse grained www.wps.prenhall.comwww.nps.gov

29. Sedimentary Rocks May contain fossils www.uky.edu www.kyu.edu

30. www.geo.cornell.edu

31. www.uky.edu www.palaeos.com www.geocities.com www.geocities.com/atrypa www.uky.edu

32.  Identification is based on particle size, particle shape, mineral composition and texture Identifying Sedimentary Rocks e.g. conglomerate/breccia, sandstone, siltstone, shale, mudstone Detrital sedimentary rocks: composed of fragmented pre-existing rocks deposited by water, wind or ice and cemented together by minerals precipitated within the void spaces

33.  Identification is based on particle size, particle shape, mineral composition and texture Identifying Sedimentary Rocks Detrital sedimentary rocks Generally composed of a combination of quartz, feldspar, rock fragments & clay minerals

34.  Identification is based on particle size, particle shape, mineral composition and texture Identifying Sedimentary Rocks Detrital sedimentary rocks Chemical sedimentary rocks Identified mostly by mineral composition (e.g. limestone, CaCO 3 )

35. Identifying Sedimentary Rocks  Clastic and nonclastic texture: www.geo.cornell.edu Clastic: sedimentary rocks made up of broken particles (all detrital rocks & some chemical sedimentary rocks)

36. Identifying Sedimentary Rocks  Clastic and nonclastic texture: Nonclastic: remaining chemical sedimentary rocks http://earthsci.org www.nps.gov

37. ROCK TEXTURE SEDIMENTARY Fragmental (clastic) Modified from Indiana Geological Survey www.eos.duke.edu

38. Common Sedimentary Rocks  Shale  Limestone  Sandstone  Conglomerate  Dolomite (Dolostone)  Siltstone  Breccia wps.prenhall.com www.rockware.com

39. Metamorphic Rocks

40. (Meta = change morph = form) Pre-existing rocks are converted to metamorphic rocks by increased temperature, pressure and/or chemical fluids

41. Metamorphic Rocks Derived from pre-existing igneous and sedimentary rocks (e.g. limestone  marble)

42. http://earthsci.org

44. Metamorphic Rocks Faulting Folding www.dc.peachnet.eduwww.dc.peachnet.edu (Charlie Watson) www.personal.rdg.ac.uk

45. Fine-grained to coarse-grained Generally classified according to texture Metamorphic Rocks www.geolsoc.org.uk Foliated (layered) parallel layers of minerals Non-foliated: no preferred orientation of minerals www.eos.duke.edu

46. IGNEOUS SEDIMENTARY METAMORPHIC Crystalline (interlocking) Fragmental (clastic) Foliated (banded) Indiana Geological Survey ROCK TEXTURES www.eos.duke.edu

47. Foliated (layers) metamorphic rock textures: Metamorphic Rocks Rock cleavage: mica crystals become aligned resulting in flat surfaces that are parallel (rock tends to split into flat slabs Increasing Temperature & Pressure http://geology.csupomona.edu

48. Foliated (layers) metamorphic rock textures: Metamorphic Rocks Rock cleavage: mica crystals become aligned resulting in flat surfaces that are parallel (rock tends to split into flat slabs Schistosity: mica crystals grow larger giving rock a “platy” or scaly look Increasing Temperature & Pressure http://geology.csupomona.edu

49. Foliated (layers) metamorphic rock textures: Metamorphic Rocks Rock cleavage: mica crystals become aligned resulting in flat surfaces that are parallel (rock tends to split into flat slabs Schistosity: mica crystals grow larger giving rock a “platy” or scaly look Banding: light & dark minerals separate giving rock a banded look Increasing Temperature & Pressure

50. Metamorphic Rocks http://geology.csupomona.edu www.geolsoc.org.uk

51. Nonfoliated metamorphic rock texture: Metamorphic Rocks http:geology.csupomona.edu

52.  Identification is based on texture and mineral composition Identifying Metamorphic Rocks

53. Common Metamorphic Rocks  Gneiss  Schist  Quartzite  Marble  Serpentine  Slate  Amphibolite http://isaac.exploratorium.edu www.geophys.washington.edu http://faculty-staff.ou.edu

54. Rock Exercise 1.Separate the rocks into igneous, sedimentary and metamorphic groups (4 each) 2.Identify the rocks using the Rock Name/Description sheet 3.Which of the igneous rocks are intrusive igneous? Extrusive igneous?

55. WOW !

56.  www.rocksandminerals.com  http://nesen.unl.edu  www.cuug.ab.ca:8001/~johnstos/geosci.html  www.bced.gov.bc.ca/irp/sciencek7/apf.htm  www.enchantedLearning.com  http://volcano.und.nodak.edu/vwdocs/vwlessons/lessons/lesson. html  http://fga.freac.fsu.edu/misc/rock.htm Suggested Websites  http://geollab.jmu.edu/Fichter/metaRx/  http://www.pbs.org

57. Evaluations