OCNG Review 1
Describe the di±erence in earthquake magnitudes that occur between the three types of plate boundaries, and include why these di±erences occur.
Convergent are deep focus don't happen as often and transform are more common but shallow focus
What are di±erences between a mid-ocean ridge and a hotspot?
Hot spots are random and spread out mid ocean ridges occur at divergent boundaries
most lithospheric plates contain both oceanic and continental crust. Use plate boundaries to explain why this is true?
Oceanic is basalt which is more dense that granite continental crustb. Volcanic chains due to mantle plumes and hotspots
How is the age distribution pattern of the Hawaiian Islands-Emperor Seamount Chain explained by the position of the Hawaiian hotspot? What could have caused the curious bend in the chain?
The hot spot bends and occurs like a lava lamp not a continuous loop of lava
what features occur at plate boundaries
convergent divergent sliding
describe seafloor spreading and why is it an important piece of evidence for plate tectonics?
is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. Its important because the magnetism "stripes" match the underwater mountain range.
what evidence supports continental drift
modern organisms have similar ancestors rocks and mountain chains match glacial ages and other glaciation and the tropics fossils
Why does a map of worldwide earthquakes closely match the locations of the worldwide plate boundaries?
most large earthquakes occur at subduction zones and earthquake activity mirrors tectonic plate boundaries.
convergent plate boundary
plates move toward each other oceanic crust destroyed: oceanic trench, volcanic arc deep focus earthquakes
Draw and describe each of the three stages of coral reef development. How does this sequence tie into the plate tectonic model?
²ringing reefs- develop along margin of landmass big volb. Barrier Reefs- separate from landmass by lagoon small volc. Atolls- reefs continue to grow after volcanoes are submerged no volume