-”Wegner used the shapes of matching shorelines on different continents as a supporting piece of evidence for continental drift. 3. Describe Earth's magnetic field, including how it has changed through time. -Similar to a simple bar magnet, ends have opposite polarities that cause magnetic objects to align parallel to it’s magnetic field. Poles have wandered from geographical position over the years.
The evidence of sea floor spreading was further supported by Vine and Drummond, who studied the magnetic pattern of the sea floor. They found that the Earth’s magnetic field changes over time, because as magma from the mantle rises to the crust it cools but the basalt will align to the field it cools to. It is also found that on either side of mid oceanic ridges there were symmetrical magnetic patterns, so suggesting that the ocean was created at the mid oceanic ridges and as new ocean floor cooled, it pushed the crust away. Both Hess and Vine and Drummond found evidence that is crucial to the explanation of how continental drift happened, and it is very important in the development of geologists understanding, however other people found evidence to support continental drift also. Dan McKenzie went on to further explain sea floor spreading, being able to explain why new crust was made at mid oceanic ridges.
He claimed that each of the present continents was once joined together as part of a super continent called Pangea. He believed this because he saw that in certain areas continents would fit together for example the west coast of Africa fits together with the east coast of South America, therefore they must have moved apart from one central mass. Other evidence was shown to back up this theory such as the fact that glacier derived clays are found in all of the continents in Gondwana forming one half of Pangea, as one striations in rocks of Carboniferous age. Presently they cover half the globe but would form a reasonably sized polar ice cap if Wegener’s theory was true and the globe was reconstructed in his image of how it used to be. Despite Wegener having no concrete proof as to why this was the case his theory was proved to be accurate, physicists had believed that the earths crust was far from strong enough to be able to force itself apart.
Assess the strength of relationship between tectonic processes and major landforms at the Earth’s surface. There is a range of evidence to suggest there is a strong relationship between tectonic processes and major landforms at the Earth’s surface due to, for example, the presence of volcanoes, fold mountains, trenches, and ridges. Tectonic processes include, divergence, which is when plates move away from each other, convergence, when plates move toward each other and collide, Subduction zones, which occur where an oceanic plate meets a continental plate and is pushed underneath, Obduction, which occurs when the continental plate is pushed under the oceanic plate, and collision boundaries, which occur where two continental plates collide and push upwards to form large mountain ranges. However this evidence is weakened by the process of weathering and erosion, due to the presence of the Grand Canyon, one of the Earth’s major landforms. As well as landforms caused by river processes, such as the Bangladesh Delta – which can be seen via satellite - therefore a major landform.
These two articles really informed me on whats happening in the world due to global warming. Greenland ice core: Frozen in time was mainly explaining how they use frozen ice to find clues about the worlds past,present and future climate. One of the first things this article goes into is celestial Effects. Celestial effects is the alterations result in
A seismometer permits seismologists to produce a map of the Planet’s inner surface. Another device that is used to utilize the measures of earthquakes is a Richter magnitude scale. This device provides figure to the quantity of seismic energy released during an earthquake. The Richter magnitude scale was created in 1935 by Charles Richter (www.geo.mtu.edu/UPSeis/intensity.html). Another way to measure the strength of an earthquake is to use the Mercalli scale.
As heat rises and cools it forces the plates in different directions; either sliding past one another, away or towards each other. At a constructive plate margin the plates are moving away from one another, this process is also known as sea-floor spreading and an example of a constructive margin is where the Eurasian plate meets the North-American plate. The Ring of Fire is the name for a ring of volcanoes around the Pacific Ocean that result at destructive boundaries where the denser oceanic plate is subducted beneath a continental plate, to form an oceanic trench. At conservative margins the plates slide sideways past each other, either in the same direction or in opposite directions. A natural hazard is a natural event that has the ability to adversely affect people and their property.
folding, faulting, down warping and up warping, volcanicity and earthquakes have formed features on the landscape of E. Africa. Main content and concepts to emphasize: By the end of the lessons students should be able to: • Identify different physical features in East Africa. • Describe the forces
Print. Kershaw, S.; Crasquin, S.; Li, Y.; Collin, P.-Y. ; Forel, M.-B. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis? Geosciences 2012, 2, 221-234.
c. intense squeezing from tectonic forces Which of the following Earth layers is the thickest? b. mantle Which of the following is true about processes that affect Earth? a. forces are imposed on deep rocks from all directions The lithosphere is made up of continental and oceanic crust. e. continental and oceanic crust Which of the following is true about gravity? .