Diamond Mines Diamonds were discovered in 1871 in Kimberley, South Africa, setting off a quot;diamond rushquot; of miners to the area.

Diamond Mines

Diamonds were discovered in 1871 in Kimberley, South Africa, setting off a "diamond rush" of miners to the area. The mine that came to be called the "Big Hole" was excavated with hand tools, by approximately 50,000 miners over about 40 years. These men produced what was at that time the largest hand-dug hole in the world.

Looking down into the lowest part of the Big Hole Source: Flickr / Gary Bembridge

Open Google Earth and the Lab 4 folder. Check and double-click on placemark Question 1a to fly to the Kimberly Diamond Mine in South Africa. Use the Look tool to rotate the view. You can do by either dragging the cursor around the outer ring or by clicking on the right and left arrows.

Fly around the mine are and observe the "Big Hole." Approximately how wide is the mine in the north-south direction? Measure between placemarks Question 1a and Question 1b using the Ruler tool.

500 m

1000 m

1300 m

1800 m

Question 2

1

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2. Question 2

[Q#4202]

The diameter of the Big Hole is your answer from the previous question. Its original depth was 240 m (although it has been partially filled in since mining ended). Assume that the entire hole is V-shaped, like a cone, with a radius of half the diameter and a height equal to the mine depth.

Using the formula for the volume of a cone (V = 1/3 π r2 h, where r = radius and h = height = depth), determine the amount of material that miners removed from the Big Hole by hand.

12 million cubic meters

16 million cubic meters

9 million cubic meters

20 million cubic meters

Question 3

1

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3. Question 3

[Q#4203]

If the total mass of material removed from the Big Hole was 22 million tonnes (metric tons), and if all 50,000 men who worked the mine moved equal amounts, how much earth did each miner dig out?

650 tonnes

320 tonnes

440 tonnes

510 tonnes

Question 4

1

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4. Question 4

[Q#4204]

The miners who moved 22 million tonnes of earth uncovered 3000 kg of diamonds in all that dirt. Diamonds made up what percentage of material removed from the Big Hole? (1 tonne = 1000 kg)

0.14%

0.0014%

1.4%

0.000014%

Question 5

1

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5. Question 5

[Q#4205]

Gold ring set with a brilliant cut diamond Source: Wikipedia

Cut diamonds that adorn jewelry may be beautiful, but the process of mining them is not quite so attractive. The region around Kimberley is noted for numerous diamond mines besides the Big Hole. Zoom out to an eye altitude of 15-20 and explore around this area.

Check placemarks Question 5, Question 6, and Question 7 and double-click one of them. Here, we see some of the unpleasant parts of the diamond mining process.

In Questions 5-7, match each placemark to its description:

Question 5:

Runoff from the tailings contaminating a nearby lake with toxic compounds

Excavated waste material (tailings) from mining operations piled on the land surface

A hole, representing part of the diamond mine

Question 6

1

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6. Question 6

[Q#4206]

Question 6:

Excavated waste material (tailings) from mining operations piled on the land surface

Runoff from the tailings contaminating a nearby lake with toxic compounds

A hole, representing part of the diamond mine

Question 7

1

point

7. Question 7

[Q#4207]

Question 7:

A hole, representing part of the diamond mine

Excavated waste material (tailings) from mining operations piled on the land surface

Runoff from the tailings contaminating a nearby lake with toxic compounds

Question 8

1

point

8. Question 8

[Q#4208]

South Africa was once the largest producer of diamonds among the countries of the world, but it has been surpassed. Botswana, which borders South Africa on the north, is currently the largest producer, and these two plus many other countries of Africa dominate world production. Search online to find which of the following countries is the largest diamond producer outside of Africa.

Canada

Australia

Venezuela

Russia

Question 9

1

point

9. Question 9

[Q#4209]

Check and double-click on placemarks Question 9a and Question 9b to see the Mir Mine in eastern Siberia, Russia's largest diamond mine. Russian geologists searching for diamonds identified the rocks in this area as kimberlite (named for Kimberley, South Africa, and now considered the most important source rock for these gemstones worldwide).

Waste material from the Mir Mine was dumped mainly on the east side of the open pit. Determine the difference in elevation between placemark Question 9a on the waste pile and placemark Question 9b next to the pile. Approximately how high is the waste pile?

25 m

20 m

10 m

15 m

Question 10

1

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10. Question 10

[Q#4210]

Gold Mines

Natural resources are plentiful in the state of Western Australia. Near the city of Kalgoorlie, miners worked several small open pit and shaft mines for gold for nearly 100 years starting in 1893. In 1989, a newly formed company bought out and consolidated several smaller operators in the area and now is working this open pit mine, informally known as the Super Pit.

A buffer zone of trees along the highway separates Kalgoorlie from the Super PitSource: Kalgoorlie Consolidated Gold Mines

Check and double-click on placemark Question 10 to fly to the Fimiston Mine in Western Australia. Keenly aware of environmental problems associated with mining in general, and open-pit mining specifically, mine operators have undertaken several steps to minimize their impact. Placemark Question 10 is located along the green belt that was established as a buffer zone between the mine and the city of Kalgoorlie and has subsequently been planted with >200,000 trees.

Use the Ruler to measure the width of this buffer zone near placemark Question 10. Pick the closest number to your measurement, using the widest part of the buffer zone.

50 m

10 m

25 m

40 m

Question 11

1

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11. Question 11

[Q#4211]

Mining generates two types of byproducts: waste rock, or non-ore-bearing material that must be removed in order to reach ore, and tailings, or leftovers from the processing mills.

Waste rock (lower right) and tailings pond at the Antamina mine in Peru Source:Flickr / Paulo Tomaz

At the Super Pit, waste rock is either used as concrete aggregate (construction material) or dumped nearby. Waste dumps are subsequently replanted and monitored to rehabilitate and reclaim the land. After the gold has been extracted, tailings remain in the form of a mixture of solid and liquid known as a slurry. This material is piped to holding ponds to dry out. The company monitors surrounding groundwater, vegetation, and birds to ensure the health of the environment.

Check and double-click on placemarks Question 11, Question 12, and Question 13

In Questions 11-13, match each placemark to the area where it is located.

Question 11:

Waste rock dump

Former dump now undergoing rehabilitation

Tailings ponds and storage facility

Question 12

1

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12. Question 12

[Q#4212]

Question 12:

Waste rock dump

Former dump now undergoing rehabilitation

Tailings ponds and storage facility

Question 13

1

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13. Question 13

[Q#4213]

Question 13:

Former dump now undergoing rehabilitation

Waste rock dump

Tailings ponds and storage facility

Question 14

1

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14. Question 14

[Q#4214]

On Niolam Island in Papua New Guinea, gold was discovered relatively recently (1982). The Lihir Mine, opened in 1995, is located within the crater of an extinct volcano right at the shoreline. Because of the mine's remote location, it has been difficult to obtain enough electricity. Residual volcanic heat produces geothermal power that supplies part of the mine's demand, and fuel oil turbines mounted on barges offshore generate extra power.

The Lihir Mine pit. Source: Flickr / Norm Hanson

Check and double-click on placemark Question 14 to see the Lihir Mine. Use the Look tool to rotate the view. Fly completely around the mine area and observe this not-so-big hole, which is beginning to tap one of the largest known gold deposits.

What is the best choice to describe this extinct crater?

It is circular.

It is conical.

It is elliptical.

It is triangular.

Question 15

1

point

15. Question 15

[Q#4215]

Because the crater is open on one side (towards the ocean), it resembles:

Both Mount Vesuvius and Mount St. Helens

Neither Mount Vesuvius or Mount St. Helens

Mount Vesuvius in Italy

Mount St. Helens in the US

Question 16

1

point

16. Question 16

[Q#4216]

There is no suitable nearby area on land to dump waste rock from the mining process, and the high seismicity of this region would make such rock piles unstable. Therefore, waste rock is either used for construction or transported by barge for submarine disposal. Similarly, tailings are piped offshore and discharged into very deep water, in a method called deep sea tailings placement. Both types of disposal are monitored for environmental impact.

What evidence is visible in Google Earth to show that mine operations are affecting the oceans, in spite of careful handling?

Forests on the west side of the mine are brown and dying.

Fertile sediment washing into the ocean has caused excessive growth of red algae ("red tide").

Shallow water near the mine is brownish in color.

White dust has settled on all of the hillsides around the mine.

Question 17

1

point

17. Question 17

[Q#4217]

Copper Mines

Copper was one of the first metals to be shaped by people, going back at least 10,000 years. We use it today for myriad purposes, from household items to heavy and high-tech industries. In fact, copper is so important to modern society that economists use its price and usage rates to indicate the economic health of a region.

Copper swords from the 17th century. Source: Wikimedia / Dbachmann

Check and double-click on placemark Question 17 to fly to the Kennecott Copper Mine in Bingham Canyon, Utah. Use the Look tool to rotate the view.

Fly completely around the mine are and observe this big hole, which is the deepest open-pit mine in the world. Pay special attention to the east and southeast edges of the mining area. What did miners do with waste rock dug from the pit? Check as many as apply.

No waste rock is visible, so it must have been trucked elsewhere for disposal.

They used waste rock from the main pit to fill in smaller side pits.

Waste rock was used as aggregate for constructing roads around the mine.

They dumped waste rock in huge piles around the sides of the mine.

Question 18

1

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18. Question 18

[Q#4218]

What is the approximate diameter of the mine between placemark Question 17 and placemark Question 18?

3.75 km

25 km

10.25 km

1.3 km

Question 19

1

point

19. Question 19

[Q#4219]

Check and double-click on placemark Question 19. Use the Hand cursor to measure the elevation difference (in m) between placemark Question 18 and placemark Question 19, in order to estimate the depth of the main pit.

500-600 m

200-300 m

1100-1200 m

800-900 m

Question 20

1

point

20. Question 20

[Q#4220]

Check and double-click placemark Question 20 to visit one of the many tailings piles. For some places around the world, Google Earth provides historical imagery back into the 1990s. To access the older images for this mine, click on the "1997" button in the lower left corner of the main window. The image should change to black and white, and a slider bar should appear in the upper left corner. Move the slider back and forth to observe changes at the mine over time.

Check and double-click on placemark Question 19 again to return to the mine pit. In April and September of 2013, two landslides occurred in the mine. Compare the images for 2011 and 2015 to see where the slides took place. Which part of the mine was affected by the landslides?

Northeast

Southwest

Northwest

Southeast

Question 21

1

point

21. Question 21

[Q#4221]

Copper mining and refining in northern Chile dates back to at least the sixth century CE (Fuller 2004). Check and double-click on placemark Question 21 and fly to the Chuquicamata Mine near Calama, Chile, on the western slope of the Andes Mountains.

Fly completely around the mine are and observe yet another big hole, this one the largest open-pit mine in the world. Could you measure diameter and depth, and use the formula for the volume of a cone to estimate how much material has been mined here, as you did in question 2 for the Kimberley Mine? (There is one correct answer, but some other answers might give you partial credit.)

No, because this mine is not circular, therefore not a perfect cone.

Yes, and the answer would be an accurate measure of the mine's volume.

No, because this mine has a flat bottom, not a single lowest point.

Yes, but the estimate would be less accurate than the estimate for the Kimberley.

Question 22

1

point

22. Question 22

[Q#4222]

Prior to about 1910, Chilean miners were extracting high-grade ore, with copper concentrations of 10-15% of the bulk volume of rock. By the twentieth century, they were mining low-grade ore, containing only 2-3% copper.

What changes would have made it economically feasible to continue mining after the high-grade ore was gone? Check as many as apply.

Higher prices for copper on world markets

Improved processes for smelting (separating metal from bulk rock)

More efficient methods of extracting and moving bulk rock

Increased demand for copper by industries