But it cannot distinguish between carbonates and sandstone as they both have similar deflections on the gamma ray log. Thus gamma ray logs cannot be said to make good lithological logs by themselves, but in practice, gamma ray logs are compared side-by-side with stratigraphic logs.
Gamma ray logs lack the ability to distinguish between carbonates and sandstone because they exhibit comparable deflections on the log. Consequently, relying solely on gamma ray logs for lithological analysis is not reliable. However, these logs are typically used alongside stratigraphic logs for comparison purposes.