• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Plate Tectonics

Extracts from this document...


Jai Mehta 11AY 1) 2) a) Plates "float" or move very slowly (a few mm per year) on the molten material of the mantle. Convection currents in the mantle cause this movement. b) Plates meet at plate boundaries or margins. c) Plates that move apart are known as diverging and are constructive, as new features are formed e.g. submarine volcanoes in the Mid Atlantic plate margin. d) Plates that move towards each other are converging and destructive - Fold Mountains, earthquakes, and volcanoes are common. e) Plates which move sideways against each other are conservative margins - material isn't gained or lost, volcanoes are rare and earthquakes are common e.g. San Andreas Fault. f) Pangaea was a single landmass; made up of all the present continents, believed to have existed between 300 and 200 million years ago the rest of the Earth was covered by the Panthalassa Ocean. Pangaea split into two landmasses Laurasia in the north and Gondwanaland in the south, which subsequently broke up into several continents. These then moved slowly to their present positions, due to plate tectonics. Jai Mehta 11AY 3) ...read more.


Since the plates on either side of a transform boundary are just sliding past each other and not tearing or crunching each other nothing happens to the land. Instead, transform boundaries are marked in some places by linear valleys along the boundary where rock has been ground up by the sliding. In other places, transform boundaries are marked by features like streambeds that have been split in half and the two halves have moved in opposite directions. The most famous transform boundary in the world is the San Andreas Fault, shown in the drawing above. The slice of California to the west of the fault is slowly moving north relative to the rest of California. Since motion along the fault is sideways and not vertical, Los Angeles will not crack off and fall into the ocean, as popularly thought, but it will simply creep towards San Francisco at about 6 centimeters per year. In about ten million years, the two cities will be side by side! Although transform boundaries are not marked by spectacular surface features, their sliding motion causes lots of earthquakes. The strongest and most famous earthquake along the San Andreas Fault hit San Francisco in 1906. ...read more.


The crash formed the Andes Mountains, the long string of volcanoes along the mountain crest, and the deep trench off the coast in the Pacific Ocean. Jai Mehta 11AY Destructive collision boundaries, these are places where two continental plates collide causing fold mountains, earthquakes, and volcanoes. Millions of people live in and visit the beautiful mountain ranges being built by plate collisions. For example, the Rockies in North America, the Alps in Europe, the Pontic Mountains in Turkey, the Zagros Mountains in Iran, and the Himalayas in central Asia these were formed by plate collisions. Each year, earthquakes and volcanic eruptions in those mountains kill thousands of people. Occasionally, big eruptions or earthquakes kill large numbers of people. In 1883 an eruption of Krakatau volcano in Indonesia killed 37,000 people. In 1983 an eruption caused mudslide on Nevada del Ruiz in Columbia and it killed 25,000 people. In 1976, an earthquake in Tangshan, China killed an astounding 750,000 people. On the other hand, earthquakes and volcanoes occurring in areas where few people live and therefore harm no one. If we choose to live near destructive collision boundaries, we can build buildings that can resist earthquakes, and we can evacuate areas around volcanoes when they threaten to erupt. 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Hazardous Environments section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Hazardous Environments essays

  1. Plate Tectonics Project.

    If, we do the thought experiment which we did in the previous section, of imagining what the line would be relative to NUVEL-1 simulation for Eurasia (as shown by the blue line), we see, by imagining the line between the tip of the blue line to the tip of the

  2. 'Ash Wednesday' 1983

    This was disastrous, as the westerly winds caused the fire to change direction. The long sides of the fire then became the head, or front, of the fire. The wind change also caused fires to merge, such as the Cudgee/ Ballangeich fire near Warnambool.

  1. Earthquakes are perhaps one of natures most breathtaking, yet deadly and destructive wonders.

    throat society were any small amount of money is snatched with both hands. Yet just at the other side of the continent exists one of the world's major business players, Japan, an economic super power. Accountable for fifteen percent of the worlds economy and equating a massive three quarters of

  2. Multiple Hazards in Cities: Examples from London, Mexico City and Los Angeles

    month, they can lead also to the closure of industry as well as many deaths. The air quality is very poor in the city of a number of reasons; * Very large population size * Large number of cars and industry * Its location in a high altitude basin *

  1. What are plate margins?

    Where do volcanoes occur? Volcanoes usually occur on the edges of plates, similar to where earthquakes occur. A lot of volcanoes occur in the area around the edge of the Pacific Ocean called the Pacific Ring of Fire. Volcanoes can also occur in the middle of plates, in hotspots.

  2. What Is The Link Between Continental Drift, Plate Tectonics, And The Development Of Earthquakes ...

    Rare glossopteris leaf fossils in coal deposits were found in South America, South Africa, India and Australia. If the areas with these fossils were looked at closely the bird's-eye-view suggests that they were one adjacent. More recently there has been the discovery of paleomagnetism, which won over the staunchest opposes to the continental drift theory.

  1. Volcanoes. All volcanoes are formed by the accumulation of magma. Most volcanoes have steep ...

    A typical volcanic is the lava dome. These are formed by relatively small, round masses of lava too thick to flow any great distance. As a result on extrusion, the lava piles over and around its vent. The dome grows largely by expansion from within.

  2. The origin of the Earth

    It also contains calcium, aluminium, and garnet, which is a complex aluminium-bearing silicate mineral. This layer is dense when cold because of the garnet. It is buoyant when hot because these minerals melt easily to form basalt, which can then rise through the upper layers as magma.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work