Refraction Survey Method
This type of survey uses refracted (or head) waves to deduce velocities of the layered-earth model. So-called first arrival information is used for the analysis (Fig. 1). More
generalized methods based on the turning waves from an arbitrary velocity model are also used in recent days. This is called seismic refraction tomography. Historically the
refraction method has been commonly used to map depth and velocity of bedrock.
This type of survey uses refracted (or head) waves to deduce velocities of the layered-earth model. So-called first arrival information is used for the analysis (Fig. 1). More
generalized methods based on the turning waves from an arbitrary velocity model are also used in recent days. This is called seismic refraction tomography. Historically the
refraction method has been commonly used to map depth and velocity of bedrock.
| Fig. 1. A field record showing that refraction waves constitute the first arrivals. |
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