It is perhaps the careful integration of geophysics with petrophysics and reservoir performance which distinguishes development and production geophysics from exploration geophysics. This is not to imply exploration geophysics is inferior, or substandard. Rather, it is a statement of fitness for purpose. In exploration, the primary objective is usually structural definition. Anomalous values of attributes such as amplitude may warrant close attention, especially when related to structural closure, but the physical cause of an anomaly may be difficult to explain and physical models ambiguous. Well data is in short supply and analysis tends toward the qualitative.