Common questions

What is the difference between seismic reflection and refraction?

What is the difference between seismic reflection and refraction?

In seismic reflection method the waves travel downward initially and are reflected at some point back to the surface, the overall path being essentially vertical. Whereas, in seismic refraction method, principal portion of the wave-path is along the interface between the two layers and hence approximately horizontal.

How the seismic refraction method is better than the seismic reflection method?

Where both techniques could be applied (i.e., the “overlap” zone), seismic reflection generally has better resolution, but is considerably more expensive due to more complex data processing requirements.

What is seismic reflection method?

Seismic reflection is a method of exploration geophysics that provides information about the sub-surface structure of the seafloor. These reflected energy waves are recorded by hydrophones, and the data are processed to produce a visual representation of the seabed sub-surface.

What causes seismic reflection?

The reflection experiment The general principle of seismic reflection is to send elastic waves (using an energy source such as dynamite explosion or Vibroseis) into the Earth, where each layer within the Earth reflects a portion of the wave’s energy back and allows the rest to refract through.

What are the limitations of seismic refraction method?

Seismic refraction methods failed to produce satisfactory results when certain conditions or combinations of conditions existed. The great depths of alluvium created the problem of estimating the seismic traverse length necessary to accurately determine the alluvium-basement interface.

What are the benefits of the seismic survey method?

The unique advantage of seismic reflection data is that it permits mapping of many horizon or layers with each shot.. At later times in the record, more noise is present in the record making the reflections difficult to extract from the unprocessed data.

What are seismic reflection profiles used for?

Our results confirm that seismic reflection profiles can give important insights on the subsurface geology of the seismically active areas and on the geometry of the seismogenic faults.

Who invented seismic reflection?

John Clarence Karcher
The first reflection patent, US Patent no. 1,843,725, was filed on 1 May 1929 by John Clarence Karcher… almost 6 months after the discovery well was completed.

What is reflection configuration?

Reflection configuration patterns can be divided into three groups: Parallel—including subparallel and divergent. Discontinuous. Prograding—caused by lateral accretion of strata.

How is the refraction method used in seismic analysis?

The seismic refraction method involves analysis of the travel times of the first energy to arrive at the geophones. These first arrivals are from either the direct wave (at geophones close to the source), or critically refracted waves (at geophones further from the source).

What is the difference between refraction and reflection?

Reflection is when waves, whether physical or electromagnetic, bounce from a surface back toward the source. A mirror reflects the image of the observer. Refraction is when waves, whether physical or electromagnetic, are deflected when the waves go through a substance.

What does refraction mean in relation to radio waves?

Refraction means the shift in direction of the radio waves, when it enters medium with different density. Light returns to the same medium. Light travels from one medium to another.

How is refractive index related to angle of incidence?

Refraction can be understood as the phenomenon of light, wherein the wave is diverted when it passes diagonally through the interface between two media of different densities. Refractive index is the ratio of the angle of incidence to the angle of refraction.