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Advantages of this method are: |
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It is a very rapid and economical method. |
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It is good up to 30m depth. |
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The instrumentation of this method is very simple. |
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It is a non-destructive method. |
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Disadvantages of this method are: |
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It can only detect absolutely different strata like rock and water. |
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It provides no information about the sample. |
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Cultural problems cause interference, e.g., power lines, pipelines, buried casings, fences. |
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Data acquisition can be slow compared to other geophysical methods, although that difference is disappearing with the very latest techniques. |
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Seismic refraction method |
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General |
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This method is based on the fact that seismic waves have different velocities in different types of soils (or rock) and besides the wave refract when they cross boundaries between different types of soils. In this method, an artificial impulse are produced either by detonation of explosive or mechanical blow with a heavy hammer at ground surface or at the shallow depth within a hole. |
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