Geology and Nonrenewable Minerals

1. Geology and Nonrenewable Minerals Chapter 12

2. Three big ideas • Dynamic forces move matter, recycle the earth’s rocks, form deposits of mineral resources, and cause volcanic eruptions, earthquakes, and tsunamis. • Mineral availability depends on quantity in the earth’s crust, rate of use, mining technology, market prices, and the harmful environmental effects of removing/using it. • We can use mineral resources more sustainably by trying to… find substitutes for scarce resources, reducing waste, and reusing and recycling nonrenewable minerals.

3. Section 12-1 What are the earth’s major geological processes and hazards?

4. The earth is a dynamic planet • Geology is the science of earth’s surface and in its interior (non-living). • Three major concentric zones. • The core is the earth’s innermost zone—extremely hot. • Surrounding the core is a thick zone called the mantle—solid rock… but part is the asthenosphere, a zone of hot, partly melted rock that flows.

5. The earth is a dynamic planet • The outermost and thinnest zone of the earth is the crust. • Continental crust, which underlies the continents. • Oceanic crust, which underlies the ocean basins and makes up 71% of the earth’s crust. • The combination of the crust and the rigid outermost part of the mantle (above the asthenosphere) is called the lithosphere.

6. The earth’s crust is made up of a mosaic of huge rigid plates

7. The earth beneath your feet is moving • Convection cells or currents move large volumes of rock and heat in loops within the mantle like gigantic conveyer belts… this powers continental drift • Plates can move/respond differently

8. Major features of the earth’s crust and upper mantle

9. The earth’s major tectonic plates

10. The San Andreas Fault

11. Internal pressure in a volcano can cause lava, ash, and gases to be ejected

12. An earthquake has certain major features and effects What is the Richter scale?

13. Earthquakes are geological rock-and-roll events • Insignificant (< 4.0 on the Richter scale). • Minor (4.0–4.9). • Damaging (5.0–5.9). • Destructive (6.0–6.9). • Major (7.0–7.9). • Great (over 8.0).

14. Earthquakes are geological rock-and-roll events • The largest recorded earthquake occurred in Chile on May 22, 1960 and measured 9.5 on the Richter scale. Google Earth… Why? http://www.neptunuslex.com/

15. How a tsunami forms What is a tidal wave?

16. Banda Aceh before and after the tsunami of December 2004

17. Earthquakes & Tsunami impacts • What can be done to minimize impacts of these geologic events? • Are they random?

18. Section 12-2 How are the earth’s rocks recycled?

19. Minerals, rocks & “dirt” • A mineral is an element or inorganic compound that occurs naturally in the earth’s crust as a solid with a regular internal crystalline structure. • Some are of a single element such as…? • Most of the more than 2,000 identified minerals occur as inorganic compounds formed by various combinations of elements, such as…?

20. There are three major types of rocks • Rock is a solid combination of one or more minerals found in the earth’s crust. • Some kinds of rock contain only one mineral (examples? ) • Most consist of two or more minerals, such as ? • Three broad classes: • Sedimentary rock (e.g. sandstone, limestone). • Igneous rock (e.g. granite). • Metamorphic rock (e.g. slate, marble).

21. Simplified rock cycle

22. Section 12-3 What are mineral resources and what are the environmental effects of using them?

23. We use a variety of nonrenewable mineral resources • A mineral resource is a concentration of naturally occurring material from the earth’s crust. • Found and extracted more than 100 minerals from the earth’s crust. • Examples are fossil fuels (such as ?), metallic minerals (such as ?), and nonmetallic minerals (such as ?). • Minerals are classified as nonrenewable resources. Why?

24. We use a variety of nonrenewable mineral resources • An ore is rock that contains a large enough concentration of a particular mineral—often a metal—to make it profitable for mining and processing. • High-grade ore contains a large concentration of the desired mineral. • Low-grade ore has a smaller concentration.

25. We use a variety of nonrenewable mineral resources • What are some examples?

26. Each metal resource that we use has a life cycle

27. Harmful effects of extraction, processing, and use of nonrenewable mineral or energy resources

28. Types of miningOpen pit, strip, contour strip, and mountaintop removable

29. Mining has harmful environmental effects • What are the negative/harmful effects? Video clip…

30. Removing metals from ores has harmful environmental effects • Ore mining typically has two components: • Ore mineral, containing the desired metal. • Waste material. • Removing the waste material from ores produces waste piles called tailings (chatt). • Heating ores to release metals is called smelting. • Without effective pollution control equipment, smelters emit enormous quantities of air pollutants, including sulfur dioxide and suspended particles. • Chemicals can be used to remove metals from their ores.

31. Section 12-4 How long will supplies of nonrenewable mineral resources last?

32. Mineral resources are distributed unevenly • What is abundant? • What is NOT abundant?

33. Mineral resources are distributed unevenly • Five nations—the United States, Canada, Russia, South Africa, and Australia—supply most of the nonrenewable minerals • Concern over 4 strategic metal resources • Manganese • Cobalt • Chromium • Platinum — these are essential for the country’s economy and military strength… little in U.S.

34. Supplies of nonrenewable mineral resources can be economically depleted • The future supply of nonrenewable minerals depends on two factors: • The actual or potential supply of the mineral. • The rate at which we use it. • Minerals may become economically depleted when it costs more than it is worth to find, extract, transport, and process the remaining deposits. Options when this occurs are: • Recycle or reuse existing supplies. • Waste less or use less. • Find a substitute or do without.

35. Market prices affect supplies of nonrenewable minerals • What are the economic issues related to mining?

36. Can we get more of our minerals from the oceans? • Issues involved with this approach?

37. Section 12-5 How can we use mineral resources more sustainably?

38. We can use nonrenewable mineral resources more sustainably

39. Three big ideas • Dynamic forces move matter, recycle the earth’s rocks, form deposits of mineral resources, and cause volcanic eruptions, earthquakes, and tsunamis. • Mineral availability depends on quantity in the earth’s crust, rate of use, mining technology, market prices, and the harmful environmental effects of removing/using it. • We can use mineral resources more sustainably by trying to… find substitutes for scarce resources, reducing waste, and reusing and recycling nonrenewable minerals.

40. The End Material beyond this point is supplemental!

41. The earth beneath your feet is moving • The forces produced at these plate boundaries can cause earthquakes, erupting volcanoes and mountains to form. • Oceanic plates move apart from one another allowing magma, to flow up between them. • Much of the geologic activity at earth’s surface takes place at the boundaries between tectonic plates as they move in the resulting cracks. • Oceanic ridges may have peaks higher and canyons deeper than those found on the earth’s continents.

42. The earth beneath your feet is moving • When two oceanic plates collide, a trench ordinarily forms at the boundary between the two plates. • When an oceanic plate collides with a continental plate, the continental plate usually rides up over the denser oceanic plate and pushes it down into the mantle in a process called subduction. • The area where this collision and subduction takes place is called a subduction zone. • Tectonic plates can also slide and grind past one another along a fracture (fault) in the lithosphere—a type of boundary called a transform fault.

43. Volcanoes release molten rock from the earth’s interior • An active volcano occurs where magma reaches the earth’s surface through a central vent or a long crack, called a fissure. • Many volcanoes form along the boundaries of the earth’s tectonic plates when one plate slides under or moves away from another plate. • Magma that reaches earth’s surface is called lava. • Volcanic activity can release large chunks of lava rock, glowing hot ash, liquid lava, and gases into the environment.

44. Earthquakes are geological rock-and-roll events • Forces inside the earth’s mantle and near its surface push, deform, and stress rocks. • The stress can cause the rocks to suddenly shift or break and produce a transform fault, or fracture in the earth’s crust. • When a fault forms or when there is abrupt movement on an existing fault, energy that has accumulated over time is released in the form of vibrations, called seismic waves, causing an earthquake.

45. Earthquakes are geological rock-and-roll events • The severity of an earthquake is measured by the magnitude of its seismic waves. • The magnitude is a measure of shaking caused by the earthquake, as indicated by the size of the seismic waves when they reach a seismograph. • Scientists use the Richter scale, on which each unit has amplitude 10 times greater than the next smaller unit.

46. Earthquakes on the ocean floor can cause huge waves called tsunamis • A tsunami is a series of large waves generated when part of the ocean floor suddenly rises or drops. • Most large tsunamis are caused when certain types of faults in the ocean floor move up or down as a result of a large underwater earthquake, a landslide caused by such an earthquake, or in some cases by a volcanic eruption. • Tsunamis are often called tidal waves, although they have nothing to do with tides.

47. Earthquakes on the ocean floor can cause huge waves called tsunamis • They can travel far across the ocean at the speed of a jet plane. • In deep water the waves are very far apart—sometimes hundreds of kilometers—and their crests are not very high. • As a tsunami approaches a coast, it slows down, its wave crests squeeze closer together, and their heights grow rapidly. • Hits a coast as a series of towering walls of water that can level buildings.

48. Earthquakes & Tsunami impacts on the ocean floor can cause huge waves called tsunamis • Tsunamis can be detected through a network of ocean buoys or pressure recorders located on the ocean floor to provide some degree of early warning sent through emergency warning centers. • Between 1900 and 2010, tsunamis killed an estimated 280,000 people along the Pacific Ocean. • The largest loss of life (279,900) occurred in December 2004 when a great underwater earthquake in the Indian Ocean with a magnitude of 9.15 caused a tsunami that generated waves as high as a five-story building.

49. Earthquakes are geological rock-and-roll events • One way to reduce the loss of life and property damage is to examine historical records and make geologic measurements to locate active fault zones. • Map high-risk areas and establish building codes that regulate the placement and design of buildings in such areas. • People evaluate the risk and factor it into their decisions about where to live. • Engineers know how to make buildings and structures more earthquake resistant.

50. Earth’s rocks are recycled very slowly • The rock cycle is the interaction of physical and/or chemical processes that change rock from one form to another. • It takes millions of years for this cycle to happen.