Introduction to Mid-Ocean Ridges:
http://oceanexplorer.noaa.gov/edu/learning/player/lesson02.html 1: Who is NOAA? The National Oceanic and Atmospheric Administration explores the geologic and biologic mysteries of the deep-sea. 2: What is the mid-ocean ridge system? What happens there? It's series of seafloor spreading centers where new earth is created. 3: How long/wide the is mid-ocean ridge system? Where is it located? It snakes across the earth at 65,000 km long and 1,500 km wide. 4: What type of plate boundary forms a mid-ocean ridge system? Explain. The mid-ocean ridge is formed by divergent boundaries pulling apart. 5: Explain how ridges form: The plates pull apart from each other and oceanic crust is formed in between them thus forming ridges. 6: What forms most of the ocean crust? Basalt forms most of the ocean crust whether it's just basalt or pillow basalt. 7: How does hot lava respond to cold sea water? (Pillow Basalt) When hot lava reaches cold sea water the outer layer of the lava solidifies but the inside doesn't cool as quickly and the lava can keep moving. |
8: What is happening at the Juan de Fuca Ridge?
New oceanic crust is formed but then broken apart. 9: What does the rate of spreading dictate?A slowly spreading ridge displays a steep irregular topography, and is relatively narrow while the Mid-Atlantic Ridge separating South America and Africa is spreading 3-4 cm/yr, producing a much wider profile and more gentle slopes. 10: How hot can sea water be heated to at the mid-oceanic ridges? It can reach temperatures of 400 degrees celsius. 11: Explain how HYDROTHERMAL Vents are formed: Super-heated water dissolves minerals and carries them along as it circulates through the crust. Eventually the mineral-laden water rises back out of the crust, boiling into the bottom of the sea through ocean floor hot springs. 12: Why is the hot mineral water so important? What do they support? The hot mineral water is vital to the life around it. 13: What is chemo synthesis? How does it differ from photosynthesis? Chemo synthesis is the process by which certain microbes create energy by mediating chemical reactions while photosynthesis is the process by which plants make energy from sunlight. |