1. Geology and Nonrenewable Mineral Resources

2. GEOLOGIC PROCESSES
The earth is made up of a core, mantle, and crust and is constantly changing as a result of processes taking place on and below its surface.

3. MINERALS, ROCKS, AND THE ROCK CYCLE
The earth’s crust consists of solid inorganic elements and compounds called minerals that can sometimes be used as resources.
Mineral resource: is a concentration of naturally occurring material in or on the earth’s crust that can be extracted and processed into useful materials at an affordable cost.

4. General Classification of Nonrenewable Mineral Resources
The U.S. Geological Survey classifies mineral resources into four major categories:
Identified: known location, quantity, and quality or existence known based on direct evidence and measurements.
Undiscovered: potential supplies that are assumed to exist.
Reserves: identified resources that can be extracted profitably.
Other: undiscovered or identified resources not classified as reserves

5. General Classification of Nonrenewable Mineral Resources
Examples are fossil fuels (coal, oil), metallic minerals (copper, iron), and nonmetallic minerals (sand, gravel).
Figure 15-7

6. GEOLOGIC PROCESSES The Rock Cycle
Deposits of nonrenewable mineral resources in the earth’s crust vary in their abundance and distribution.
A very slow chemical cycle recycles three types of rock found in the earth’s crust:
Sedimentary rock (sandstone, limestone).
Metamorphic rock (slate, marble, quartzite).
Igneous rock (granite, pumice, basalt).

7. ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES
The extraction, processing, and use of mineral resources has a large environmental impact.
Figure 15-9

8. Open-pit Mining
Machines dig holes and remove ores, sand, gravel, and stone.
Toxic groundwater can accumulate at the bottom.
Figure 15-11

9. Area Strip Mining
Earth movers strips away overburden, and giant shovels removes mineral deposit.
Often leaves highly erodible hills of rubble called spoil banks.
Figure 15-12

10. Contour Strip Mining Used on hilly or mountainous terrain.
Unless the land is restored, a wall of dirt is left in front of a highly erodible bank called a highwall.
Figure 15-13

11. Mountaintop Removal
Machinery removes the tops of mountains to expose coal.
The resulting waste rock and dirt are dumped into the streams and valleys below.
Figure 15-14

12. Mining Impacts
Metal ores are smelted or treated with (potentially toxic) chemicals to extract the desired metal.
Figure 15-15

13. SUPPLIES OF MINERAL RESOURCES
New technologies can increase the mining of low-grade ores at affordable prices, but harmful environmental effects can limit this approach.
Most minerals in seawater and on the deep ocean floor cost too much to extract, and there are squabbles over who owns them.

14. Getting More Minerals from the Ocean
Hydrothermal deposits form when mineral-rich superheated water shoots out of vents in solidified magma on the ocean floor.
Figure 15-17

15. USING MINERAL RESOURCES MORE SUSTAINABLY
Scientists and engineers are developing new types of materials as substitutes for many metals.
Recycling valuable and scarce metals saves money and has a lower environmental impact than mining and extracting them from their ores.

16. Sustainable Use of Nonrenewable Minerals
Solutions
Sustainable Use of Nonrenewable Minerals
• Do not waste mineral resources.
• Recycle and reuse 60–80% of mineral resources.
• Include the harmful environmental costs of mining and processing minerals in the prices of items (full-cost pricing).
• Reduce subsidies for mining mineral resources.
• Increase subsidies for recycling, reuse, and finding less environmentally harmful substitutes.
• Redesign manufacturing processes to use less mineral resources and to produce less pollution and waste.
Figure 15.18
Solutions: ways to achieve more sustainable use of nonrenewable mineral resources. QUESTION: Which two of the solutions do you think are the most important?
• Have the mineral-based wastes of one manufacturing process become the raw materials for other processes.
• Sell services instead of things.
• Slow population growth.
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