Learning target: I can describe a pattern in where a natural resource is found and propose a first explanation that connects the pattern to processes inside Earth.
Read the phenomenon and study the table and the figure. The table lists real mines; the figure sums up the pattern. Fill in your notice-and-wonder chart before you talk to anyone. Then share one notice and one wonder with a partner and add anything new to your chart. Finish by writing your own first explanation. It does not need to be right; it needs to be yours, and it needs to use the evidence on this page.
You will need: This worksheet, Pencil, A world map or atlas (optional, for the extension)
Copper is in nearly everything that carries electricity: the wires in a wall, the motor in a fan, the tiny circuits in a phone. The world uses more than 20 million tonnes of newly mined copper every year. You might expect copper mines to be spread out wherever people need copper. They are not. A geologist who marks the largest copper mines on a world map sees a crooked line running down the western edge of the Americas, from Arizona and Utah through Mexico, Peru and Chile. A few more big mines sit on islands and mountain ranges in the western Pacific and in central Asia. Huge regions have no large copper mine at all: the flat farmland of the central United States, the Florida peninsula, the Hawaiian Islands, most of Europe. Those places have rock, rain and plenty of people who would like cheap copper. What they do not have is copper ore, rock with enough copper in it to be worth mining.
| Mine | Country | Landscape | Plate setting when the ore formed |
|---|---|---|---|
| Escondida | Chile | Atacama Desert, in the Andes | Above the zone where the Nazca Plate sinks beneath South America; still active today |
| Chuquicamata | Chile | Northern Chilean Andes | Same subduction zone as Escondida; still active today |
| Cerro Verde | Peru | Andes near Arequipa | Same subduction zone; still active today |
| Bingham Canyon | United States (Utah) | Oquirrh Mountains near Salt Lake City | Magma that rose above an ancient subduction zone tens of millions of years ago; no longer active there |
| Morenci | United States (Arizona) | Mountains of southeastern Arizona | Magma above an ancient subduction zone tens of millions of years ago; no longer active there |
| Grasberg | Indonesia | High mountains of Papua | Near the collision of the Australian and Pacific plates; still active today |
| Oyu Tolgoi | Mongolia | Gobi Desert | An ancient chain of volcanoes above a subduction zone hundreds of millions of years ago; the plates have since rearranged |
| I notice (something I can point to in the table or figure) | I wonder (a question it raises) |
|---|---|
| 1 | |
| 2 | |
| 3 |
If the blank page is hard to start, use these frames and fill the gaps: 'All seven mines are located where ______ (from the table).' 'At that kind of plate boundary, ______ happens (from Part B).' 'So I think copper ore forms when ______.' 'That would explain why the farmland has no mines, because ______.' You can also point at the figure: the left column lists what copper country has that the right column lacks.
Geothermal power plants and hot springs also cluster in a pattern on the world map. Predict, before looking, whether that pattern overlaps the copper line, and explain why it might. Then check your prediction using a map of the world's plate boundaries and a list of countries with geothermal plants (Iceland, New Zealand, Indonesia, the Philippines, Kenya, the United States). Write three sentences: what overlapped, what did not, and one difference between how copper ore and geothermal heat are 'made'.