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Plate Boundaries
Question | Answer |
---|---|
Tectonic Plates | It's the theory that Earth's outer crust (lithosphere) is divided into several plates that glide over the asthenosphere (upper mantle). |
Volcanic Islands | Made from converging (oceanic/oceanic) the older crust goes below the other one and creates a volcanic arc of islands Subduction zone |
Mountain Range | Converging (continental/continental) this pressure causes both plates to rise creating folded mountains not a subduction zone |
Subduction Zone | A place where plates meet, and if it is continental/oceanic the oceanic goes under, and if it is oceanic/oceanic the older one goes under. |
Earthquake | Happens with a transform boundary - plates slip sideways past each other |
Plate Boundary | At plate boundaries plates do one of 3 things - Converge (Colliding/coming together), Diverge (dividing/moving apart), or Transform (sliding past each other) |
Transform Boundary | Plates slip sideways past each other creating earthquakes, crust is neither created or destroyed, many of these boundaries are found on the sea floor, the most famous transform boundary is the San Andreas fault in California. |
Himalayan Mountains | Created by a Converging boundary with continental/continental, the 2 plates collide and push against each other |
Convergent Boundary | (continental/cont.)2 continental crusts collide & push against each other-plates rise-creates folded mountains no subduction, (cont./oceanic)-the ocean crust under cont.-its more dense-volcanoes on cont.-trench in ocean-subduction |
Divergent Boundary | Two oceanic crusts diverge and create a mid-ocean ridge (mountains under the ocean), sea-floor spreading, new crust is created, two continental crusts diverge and create a rift valley, new crust is created, example is the Great Rift Valley in Africa |
Subduction Boundary | When the either continental/oceanic or oceanic/oceanic meet, the oceanic crust (or older one) goes underneath which creates a trench and volcanoes on the continental side or (if no continent) the magma rises and cools creating islands |
Mid-Atlantic Ridge | Caused by a divergent boundary when 2 oceanic crusts diverge (Mid-Atlantic Ridge is mountains under the ocean) |
Converging | Coming together |
Diverging | Dividing/moving apart |
Volcano | Form when continental hits oceanic, Ex. Cascades in Oregon and Washington |
Seafloor Spreading | Harry Hess discovered that the seafloor was spreading which is caused by magma rising, hot magma rising in the mantle which caused the seafloor to spread and tectonic plates to move |
Mid-Ocean Ridge | Formed when to oceanic crusts diverge |
Ring of Fire | A long chain of volcanoes that surround the Pacific Ocean, one of the most geologically active area on Earth site, of frequent earthquakes and volcanic eruptions, caused by plate boundaries converging, diverging and transforming |
Convection Currents | Transfers energy in the mantle, causes the hotter magma in the mantle to rise, causes the cooler magma in the mantle to sink |
Trench | When ocean involved a trench is formed where plates collided (converging), either oceanic/oceanic or continental/oceanic |
San Andreas Fault | Transform boundary, very big & it runs all through California |
Cascades Volcanoes | Volcanoes in Oregon and Washington that formed by convergent boundary when continental and oceanic collide |
Rift Valley in Africa | Formed when 2 continental crusts diverge which creates a rift valley |
Convergent boundary (continued) | (oceanic/oc.) collide and push against each other-the older crust goes below the other one and creates a volcanic arc of islands. Subduction zone |