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Plate Tectonics. The Earth’s crust consists of a number of plates which are in motion (quite slow). The Layers of the Earth.
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Plate Tectonics The Earth’s crust consists of a number of plates which are in motion (quite slow)
The movement of crustal plates results from convection currents in the Mantle. Heat from the formation of the Earth and radioactive decay escapes at the Earth’s surface.
Some plates contain mainly oceanic crust and some contain both continental and oceanic crust.
The Glomar Challenger was the first research vessel specifically designed in the late 1960s for the purpose of drilling into and taking core samples from the deep ocean floor.
Remote Sensing- uses energy signals from Earth to determine many different kinds of information
Earthquake and Volcano Activity closely matches the plate boundaries!
Computer-generated detailed topographic map of a segment of the Mid-Oceanic Ridge
Shortcut to Sea Floor SpreadingShortcut to Formation of Ocean Crust
There is evidence of “Sea floor spreading” on either side of the Mid-Atlantic Ridge
Divergent boundaries occur along spreading centers where plates are moving apart and new crust is created by magma pushing up from the mantle.
Iceland is right on an oceanic-oceanic Divergent Plate Boundary
Convergent boundaries are where plates are moving toward each other, and sometimes one plate sinks (is subducted) under another. The location where sinking of a plate occurs is called a subduction zone. subduction
Deep trenches are formed in the ocean floor where subduction begins
Oceanic-oceanic convergent boundaries produce volcanic Island Arc’s
An oceanic-oceanic convergent boundary. They also produce a trench
The Mariana Trench is the deepest known trench. The bottom of the trench (Challenger Deep) is further below sea level than Mount Everest is above it. The trench has a maximum depth of 10,911 m (35,798 feet) below sea level.
Continental-continental Convergent plate boundaries can produce mountain ranges.
Transform Boundaries The zone between two plates sliding horizontally past one another is called a transform-fault boundary, or simply a transform boundary. transform faulting