I believe that the textural terms for many lithologic fill patterns are incorrect. Specifically, the concepts of grading and sorting appear to have been substituted for one another, which has resulted in textural descriptions that do not match the corresponding fill pattern. The term "well-graded" describes sediment that is composed of a range of grain-size classes, and is mostly used by the soil science or soil engineering community. To describe the same thing, most geologists use the term sorting, and in the case just described, the sediment would be described as "poorly-sorted." The opposite is true..."poorly-graded" is the same as "well-sorted." To further muddy the water, the term grading is used by geologists to describe vertical trends in grain-size, e.g., "normal-graded" to indicate a fining-up sequence.
I would suggest sticking to one system or the other (as a geologist, I vote for "sorting") and correct the descriptions that are in error. Most of the errors fall within the USGS 100 series (e.g., fine, well-graded sand; etc.). Curiously, the only description that employs "sorting" (medium, well-sorted sand) appears appropriate to the corresponding fill pattern. Also, the USCS patterns are incomplete (missing GP, SW, SP, SC, ML, CL, MH, CH) and some of the patterns supplied are incorrect.
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