The ROCK CYCLE

1. The ROCK CYCLE

2. The ROCK CYCLE Init <<3/4/2008 by Daniel R. Barnes WARNING: Many of the images in this presentation were taken without permission from other people’s web sites. Do not copy or distribute this presentation. Its very existence may be illegal.

4. What do you call melted rock that’s still underground? magma

5. What must happen to magma for it to turn into rock? cooling magma

6. What kind of rock does magma turn into when it cools enough to crystallize? igneous rock cooling magma

7. intrusive Igneous Rock Igneous rock forms when liquid rock cools and solidifies. If igneous rock forms underground from magma, it will cool slowly, allowing large crystals to form. Igneous rock that forms undergound from magma is called “intrusive” igneous rock. Granite, with its spotty, coarse texture, is a good example of intrustive igneous rock. granite

8. extrusive Igneous Rock Igneous rock forms when liquid rock cools and solidifies. If igneous rock forms on the surface of the earth, from lava, it cools relatively quickly, and this doesn’t give large crystals a chance to form. Lava rock is called “extrusive” igneous rock. Furthermore, lava gives off gas easily because of the low pressure here at the earth’s surface, If this happens during cooling, the resulting lava rock can have a bubbly, “vessicular”, swiss cheese-like structure. basalt Basalt is a good example of extrusive igneous rock. It’s what Hawaiian volcanoes are made of.

9. What kind of rock of rock is this? igneous rock granite cooling magma

10. What can cause the crystals in igneous rock to re-crystallize? heat &/or pressure igneous rock cooling magma

11. What kind of rock is produced when heat &/or pressure re-crystallize the rock? heat &/or pressure metamorphic rock igneous rock cooling magma

12. Metamorphic Rock “Metamorphic” rock has gone through metamorphosis, a great change. You may be more familiar with biological examples metamorphosis than you are with geological examples. For instance, you know that a caterpillar metamorphoses into . . . . . . a butterfly.

13. Metamorphic Rock “Metamorphic” rock has gone through metamorphosis, a great change. You may be more familiar with biological examples metamorphosis than you are with geological examples. You also know that a tadpole metamorphoses into . . . . . . a frog.

14. Metamorphic Rock Metamorphic heat pressure. Metamorphic rock forms when pre-existing rock is subjected to heat and/or pressure. heat pressure. During metamorphosis, heat and pressure cause atoms in mineral crystals to pop out of place and pop back in somewhere else. If there is pressure directed in one direction, crystals can get smashed, producing a metamorphic rock with “foliated” system of layers. foliation can be very wavy Foliated layers in metamorphic rock are sometimes quite wavy, unlike the layers in sedimentary rock, which are often perfectly flat and straight. gneiss

15. Metamorphic Rock Heat and pressure can turn the igneous rock granite into the metamorphic rock gneiss. granite gneiss

16. m e t a m o r p h o s i s

17. m e t a m o r p h o s i s HEAT & PRESSURE

18. What kind of rock is this? gneiss heat &/or pressure metamorphic rock igneous rock cooling magma

19. What can turn metamorphic rock back into magma? heat &/or pressure metamorphic rock igneous rock extreme heat cooling magma

20. weathering heat &/or pressure metamorphic rock What can turn any kind of rock into little bits of dirt, sand, or gravel? igneous rock extreme heat cooling magma

21. sediment What do you call the tiny bits of rock produced by weathering? weathering heat &/or pressure metamorphic rock igneous rock extreme heat cooling magma

22. sediment erosion weathering What do you call it when sediment moves from place to place? heat &/or pressure metamorphic rock igneous rock extreme heat cooling magma

27. The light blue rivers aren’t really light blue. That’s false color added with a computer.

28. Solimões and Negro Rivers The largest river on the planet, the Amazon, forms from the confluence of the Solimões (the upper Amazon River) and the Negro at the Brazilian city of Manaus in central Amazonas. At the river conjunction, the muddy, tan-colored waters of the Solimões meet the "black" water of the Negro River. The unique mixing zone where the waters meet extends downstream through the rainforest for hundreds of miles, and attracts tourists from all over the world, which has contributed to substantial growth in the city of Manaus. It is the vast quantity of sediment eroded from the Andes Mountains that gives the Solimões its tan color. By comparison, water in the Negro derives from the low jungles where reduced physical erosion of rock precludes mud entering the river. In place of sediment, organic matter from the forest floor stains the river the color of black tea. The Solimões provides nutrient-rich mud to lakes on the floodplain (lower right). The ecology of muddy lakes differs correspondingly from that of nutrient-poor, blackwater rivers and lakes. Solimões water can be seen leaking into the Negro west of the main meeting zone (lower left). The Solimões is much shallower than the Negro because it has filled its valley and bed with great quantities of sediment since the valleys were excavated. Widths of the rivers differ for this reason. Image credit: NASA http://www.nasa.gov/multimedia/imagegallery/image_feature_577.html

30. sediment erosion deposition weathering What do you call it when sediment settles down and stops moving? heat &/or pressure metamorphic rock igneous rock extreme heat cooling magma

31. sediment erosion deposition weathering compaction & cementaion heat &/or pressure metamorphic rock What two processes turn sediment into rock? igneous rock extreme heat cooling magma

32. sediment erosion deposition weathering compaction & cementaion sedimentary rock heat &/or pressure metamorphic rock What do compaction and cementation turn sediment into? igneous rock extreme heat cooling magma

33. Sedimentary Rock Sedimentary rock forms from bits of rock (sediments) and/or minerals that crystallize from solutions. Shale is the most common form of sedimentary rock. It forms from millions of tiny clay particles that accumulate slowly over long periods of time to form layers, year after year, typically at the bottom of lakes, seas, or oceans. Limestone is made of calcium carbonate, which could come from seashells, microplankton shells, or from ions dissolved in seawater that have crystallized. shale & limestone

34. Sedimentary Rock Sedimentary rock forms from bits of rock (sediments) and/or minerals that crystallize from solutions. Limestone was used in large quantities to build the pyramids of ancient Egypt. Limestone is made of calcium carbonate, which could come from seashells, microplankton shells, or from ions dissolved in seawater that have crystallized. shale & limestone

35. Sedimentary Rock Sedimentary rock forms from bits of rock (sediments) and/or minerals that crystallize from solutions. Sedimentary rock layers are very obvious in the cliff walls of the Grand Canyon. These layers tell a story. The old layers are at the bottom, the younger layers on top. younger rocks & fossils older rocks & fossils