Seismic volumes are difficult to interpret, since the ever present sedimentary bedding and a wide variety of other geological features usually crowd the seismic subsurface image. The image is opaque and is usually inspected in extracted two-dimensional sections.
The human eye excels in the recognition of subtle trends in otherwise noisy and incoherent data. On the other hand, the eye being restricted to two-dimensional sections is handicapped in grasping the image's volumetric features. For example, within a two-dimensional section, a fault is invisible if it intersects a sedimentary layer in strike direction. If the eye could assimilate the opaque image volume, the presence of the fault would easily be deduced from its existence in nearby image regions. However, the identification of geological features in seismic sections by an interpreter is time consuming and subjective (nonreproducible). Discontinuity maps cannot replace the human interpretation of seismic sections. The maps can, however, help to locate faults, river channels, and other geological boundaries
The synthetic seismic data set represents an idealized sedimentary fault. The fault is simply defined by the offset and of the adjacent plane-waves volumes. In that sense, the synthetic does not represent a fault reflection or transition zone of gnarled rock.
In the two seismic test cases, the major discontinuities are faults. The Gulf salt dome image additionally contains major salt boundaries. With respect to discontinuity attributes, the most important difference between the two seismic examples is the sharpness of their faults. The fault surfaces of the Gulf salt dome image 7 are significantly sharper than the fault surfaces of the North Sea horst image 11.
The image volumes of the two seismic test cases differ. The size difference of the two image volumes slightly complicates a direct comparison. The larger salt dome time slice appears less grainy than the horst's. Furthermore, little blemishes are bound to disappear in the larger image. Also, the vertical sections of the horst display more than double the time of the corresponding salt sections. Naturally, the images are much more illuminating when displayed on the screen of a graphics workstation.