Friday, June 6, 2008

Exam 1

There are three types of plate boundaries and they include divergent, convergent, and transform.

Divergent
A divergent plate boundary is a linear feature that exists between two tectonic plate sthat are moving away from each other. Most active divergent plate boundaries exist between oceanic plates. Divergent plate boundaries usually form ocean basins. Mid ocean plates are formed from divergent plate bondaries.

Convergent
is an actively deforming region where two tectonic plates or fragments of lithosphere move toward one another and collide. During collisions between two continental plates, large mountain ranges are formed. A subducton zone is formed at a convergent plate boundary when one or both of the tectonic plates is composed of oceanic crust. The denser plate, made of oceanic crust, is pushed underneath the less dense plate, which can be either continental or oceanic crust. Volcanoes are formed from convergent boundaries pushing up on each other. One plates goes under the other and makes a volcanoe. Covergent boundaries can produce volcanic arcs as well. A volcanic arc is a chain of volcanic islands or mountains.
Image of a graph that displays the Convergent Plate Boundary.  Please have someone assist you with this.
Transform
A transform fault is a fault which runs along the boundary of a tectoniic plate. The relative motion of transform plates is horizontal in either sinistral or dextral direction. The left- or right-lateral motion of one plate against another along transform faults can cause highly visible surface effects. Earthquakes often occur alone transform faults. Continental rifts often form along transform faults. A continental rift is a linear-shaped lowland between highlands or mountain ranges created by the action of a geologic rift or fault.

There are three types of volcanoes. They are shield volcanoes, stratovolcanos, and cinder cones.

Shield Volcanoes
A shield volcano is a large volcano with shallow-sloping sides. Shield volcanoes can be so large that they are sometimes considered to be a mountain range. Shield volcanos haved formed on other planets.he largest known mountain in the solar system, Olympus Mons on Mars, is a shield volcano.

Strato Volcano
A stratovolcano is a tall, conical volcano composed of many layers of hardened lava, tephra, and volcanic ash.

Cinder ConeA cinder cone is a steep conical hill of volcanic fragments that accumulate around and downwind from a volcanic vent.

Ring of fire
Pacific Ring of Fire is an area of frequent earthquakes and volcanic eruptions encircling the basin of the Pacific Ocean. It's a 40,000 km horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, and plate movements.












If people understand how volcanos and plate tectonics work they will know when to leave if a volcano is about to erupt. It is for the common good of society. Also if we understand volcanos people will know how land is formed.

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