QUESTION 1
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1.1 Draw a well labelled diagram of the earth's structure, showing the mechanical
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subdivision, and the continental and oceanic crust.
1.2 What materials are in the continental crust?
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1.3 List any of the four major tectonic plates.
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1.4 Briefly explain the following mechanical subdivisions of the earth.
1.4.1 Asthenosphere
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1.4.2 Siderosphere
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QUESTION 2
2.1 Define seismic velocity.
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2.2 What are body elastic waves? Briefly outline the Characteristic difference between
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these waves.
2.3 What do you understand by the term dipping angle (oc) of a single horizontal reflection? (5)
2.4. What is the crossover distance for direct and critically refracted rays in the case of an (8)
horizontal interface at a depth of 200 m separating a top layer of velocity 3.0 km/s from a
lower layer of velocity 5.0 km/s
2