Gestalt psychology and the recognition of complex sedimentary structures in geology

Abstract

Gestalt is an untranslatable German word that is employed in the visual perception theory based in the psychology of forms. This theory says that it cannot have knowledge of the whole from its parts, but inversely the parts from the whole. The Gestalt theory has several laws, which the Prägnanz (or simplification) law seems to be the more applicable to the perception of complex sedimentary structures like the hummocky cross stratification (HCS). After several years of geological mapping by experienced geologists this structure could be recognized as a very common sedimentary feature in the intracontinental basins. This recognition only could be made using unconsciously the Gestalt approach. In field courses, in the Parnaíba Basin, students only recognized HCS after a simplification according to the Prägnanz law. Other structures, like the catastrophic-flood delta mouth-bar section, were detected using the same approach. Detection of oversized features -like giant-ripple cross bedding -from the Gestalt approach is also discussed.