Mountain Building

1. Mountain Building

2. Faults • A fault is a fracture or in the Earth’s crust that occurs when stress is applied too quickly • Area where Earthquakes occur • Reverse • Normal • Strike Slip

3. Reverse Faults • Reverse faults occur as a result of compression • Hanging Wall-The upper part of fault • Footwall-The lower part of a fault

4. Normal Faults • Normal faults occur as a result of tension • 2 pieces of crust are pulled apart

5. Strike Slip Faults • Strike slip faults occur as a result of shear stress • 2 pieces of lithosphere are pulled passed each other • San Andreas Fault (San Francisco)

6. Orogenies • An orogeny is a process that forms mountains • Alleghanian Orogeny • Formed the Appalachians, Paleozoic

7. Ocean Ridge Mountains Ocean ridge mountains form when plates diverge and magma rises to the surface

8. Uplifted Mountains • Uplifted mountains form when large regions of Earth have been slowly forced upward as a unit

9. Fault Block Mountain • A fault block mountain forms when large pieces of crust are tilted, uplifted or dropped downward between large faults

10. Geologic History of the Carolinas and the Piedmont

11. Geologic Time Scale • The geologic time scale is a record of Earth’s History • The Earth is 4.6 Billion Years Old • The time scale is divided into different subdivision • Orogenesis - general term for the processes that produce mountains • Orogeny-Mountain building event (plate collision)

13. North Carolina Geologic Events • 3.8 Bya-First life forms evolved • Single celled organisms • 3.5 Bya-The first continents began to form • Convection began due to unequal heating of the mantle (plate tectonics)

14. North Carolina Geologic Events • 1.7 Bya- Present day North Carolina formed • 1.3 Bya-The first mountains of North Carolina formed • Grenville mountains (no longer exist due to erosion) • Formed by Grenville Orogeny • Oldest rocks of NC formed. Presently exposed in the Appalachian Mountains

15. North Carolina Geologic Events • 1 Bya-First multicellular organisms • 620 mya-North Carolina was pulled apart by tectonic forces • Volcanoes developed along NC-VA border

16. North Carolina Geologic Events • 750-540 mya-North America and Europe/ Africa moved towards each other • Formed Kings Mountain Belt • Formed first supercontinent Rodinia • Grenville orogeny • 542 mya-”Cambrian Explosion” – Major diversification of life • First vertebrates • North Carolina was underwater

17. 750 - 540 MYA Supercontinent of Rodinia (Grenville Orogeny)

18. North Carolina Geologic Events • 496-440 mya-Taconic Orogeny: The coastline of present day Appalachian Mountains collided with Iapetus Plate (Oceanic Plate) • Formed volcanic mountains in present day North Carolina

20. North Carolina Geologic Events • Acadian Orogeny(400-325 mya): A continent called Avalonia collided with present day North America • Continued the formation of the Appalachian mountains. • Also lead to the formation of Pangaea

21. North Carolina Geologic Events • 359 mya-Wetland forests dominated the Appalachian area • The decayed organic matter from the trees eventually lead to coal that is currently mined today

22. Alleghanian Orogeny • AlleghanianOrogeny(325-260 mya): Africa collided with North America. • Resulted in the formation of the Appalachian Mountains • Pangaea was fully assembled

23. North Carolina Geologic Events • After the formation of Pangaea, the Appalachian Mountains were near the center of Pangaea • Central Pangaea Mountains Extended into what is now Scotland and Morocco

26. North Carolina Geologic Events • 251 mya-Appalachians began to erode • Wind and rain  Sediment was carried to lower lying land or sea • Pangaea was breaking up • 200 mya-As Pangaea separated the Atlantic Ocean formed • Outer margin became the outer banks

27. North Carolina Geologic Events • 145 mya-65 mya: Coastal Plains were underwater but sea level began to drop • Dinosaurs went extinct • 65 mya: Coastal plains were above water • 5 mya-Blue Ridge and Piedmont were as they are today

28. North Carolina Geologic Events • 1.7 mya-”Ice Age” began. Sea level in North Carolina fell • There is present day evidence in the Coastal Plains • 18,000 years ago – Glaciers melted • 10,000-15,000-North Carolina’s forests began to develop • 9,000 BC-Human civilization began

29. Warm upMonday September 30th • Complete the Earth Science Word Search in 12 min for a science ticket

30. Warm upTuesday October 1st • Name the 3 types of faults • What orogeny created the Appalachian Mts? • What type of mountains are formed when large pieces of crust are tilted, uplifted or dropped downward

31. Birth of the Mountains Reading Activity • Read the handout titled “Birth of Mountains”. • On a separate sheet of paper, in complete sentences, write down the 2 most important facts that you learned from each of the following sections…. a. Introduction b. Reading the Rocks c. A Supercontinent Forms d. The Supercontinent Breaks Up e. Continental Collisions f. Carving the Mountains

32. Warm upWednesday October 2nd • Look over your NC Earth History notes from yesterday. Pop quiz to follow!!