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Plate XXI. Mississippian Facies

(A) Lime mudstone-wackestone of Waul sort ian mound. Sample AGR is from the
top of the mound at the north side of the mouth of Alamo Canyon, Sacramento
Mountains, New Mexico and is composed of fine bioclastic debris of crinoids,
ostracods, and shreds of bryozoan. The round discs with holes and arrowhead-
shaped particles are crinoid stems and arm plates respectively. This is the typical
composition of the all Waul sort ian mounds in the Sacramento Mountains (see
Chapter V). Thin section, x 15
(B) Encrinite-crinoidal bryozoan packstone. Sample AGN typifies flank facies
off the same Waulsortian mound of which the above sample AGR is typical. Note
sutured contacts of crinoid particles owing to microstylolitization during early
compaction (see Chapter V). Other encrinites representing this special kind of
standard microfacies 12 are seen in Horowitz and Potter 1971, Plates 83, 89, 91,
97. Encrinites are very common flanking beds of Paleozoic and early Mesozoic
mud mounds developed in water of varying depths. Thin section, x 15