Seismic Reflection

Seismic reflection surveys are based on the propagation of elastic waves in the subsurface. With the help of an energy source at the surface, artificial waves that propagate into the subsurface with a specific rock-depending velocity are induced. The type of energy source depends on the reconnaissance depth. Sources can be explosives, hammer (reconnaissance depth between 50 – 200 m), drop weights (100 – 500 m), or vibrators (300 – 10000 m). The artificial waves propagate into the subsurface and are reflected at sequence boundaries. On the surface the reflected waves are recorded using geophones. The source position is moved along the profile to record a set of shotgathers. In seismic processing these single shotgathers are combined to form a digital image (SEGY) of the subsurface. This seismic image can then be interpreted regarding horizons, faults or fractures.

Seismic reflection surveys can be used in various fields of application. Depending on the field of application the depth of investigation and the resolution of the seismic data vary.