During the Permian, how would the Kaibab Formation, consisting of sandy limestone, be depicted in a lithologic log?

In a lithologic log, the Kaibab Formation, which is primarily composed of sandy limestone, would be accurately represented by modifying the limestone symbol to reflect the presence of sand. This is because the sandy limestone has characteristics of both limestone and sandstone, indicating a mixed composition. The modification allows for a more precise representation of the formation's lithology, capturing the essential features of the rock type.

The use of a modified symbol helps anyone reading the log to quickly understand the geological composition of the formation without overly simplifying or misrepresenting it. It conveys the idea that while limestone is the dominant material, the sandy component is significant enough to affect the properties and visual appearance of the rock. This kind of representation is crucial for geological interpretation, as it helps geologists infer additional characteristics and behaviors related to resource potential, such as porosity and permeability.

This approach contrasts with the other potential representations, which would not accurately reflect the mixed nature of the Kaibab Formation. Depicting it as a standard limestone block would omit the critical sandy characteristic, while separating limestone and sand into distinct blocks would not effectively communicate their co-occurrence within the formation. Lastly, omitting the depiction entirely would disregard important geological information. Thus, modifying the limestone symbol is