In a petrophysical sense, thin beds can be defined as beds that are thinner than the resolution of the logging tools used to characterize them. This implies that the direct log values do not represent the true bed or layer properties, but rather an average of multiple beds. In the typical case of sand interbedded with shale, the logs will reflect an average of sand and shale properties. Direct interpretation of the log readings will therefore result in a significant underestimation of reservoir quality. Once such a scenario has been recognized, an interpretation methodology can be chosen that takes the inadequate log resolution into account. One such method is the Thomas-Stieber method