Distinction of intrabasinal, diagenetic, or clastic genesis for very fine-grained
carbonate minerals is interpretive in many cases. If there is uncertainty on the mudstone
category based on intrabasinal vs epiclastic distinction required for clastic sedimentary
rock-carbonate sedimentary rock categorization in this system, it is recommended to
use the generic_mudstone category. This category is the union of the various fields
labeled 'mudstone' with various qualifiers in Folk, 1954, Figure 1a, although Folk's
(1954) category labeled 'mudstone' is a much more restricted category. The CGI category
is equivalent to category labeled 'Mudrock' in SLTTs (2004), not to the category labeled
'Mudstone' adopted by that system from Folk (1954). Schnurrenberger, D., Russell,
J. and Kelts, K., 2003, Classification of lacustrine sediments based on sedimentary
components: Journal of Paleolimnology, v.29, p141-154.
source
Pettijohn et al. 1987 referenced in Hallsworth and Knox 1999.