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Plate III. Mesozoic Pelagic Lime Mudstones,
Standard Microfacies 3

(A) Dense, dark micrite with some microbioclasts. The photograph contains a
pelagic crinoid or ophiuroid plate. Sample is from basinal, off-bank strata of the
Mexican miogeosyncline, basal Tamaulipas limestone (Lower Cretaceous), in the
Peregrina Canyon. Tamaulipas, Mexico, (Chapter XI). Thin section, x 36

(B) Calpionellids in dove gray, laminated pelagic micrite. Sample Jur-16 is
from type Oberalmkalk (Maiolica or Biancone facies) of the Austroalpine nappes.
Such sediment is common in the latest Jurassic (Tithonian) troughs within the
Tethyan geosyncline, facies J -14. Thin section, x 90

(C) Oligostegina (calcispheres) and globigerinid foraminifera in dark micrite
(wackestone). Typical off-reeffacies of Middle Cretaceous basins and basin edges.
Cenomanian to upper Albian "Georgetown" overlying the Deep Edwards Reef.
Gulf Tartt No.1 well, 10410-15H feet, Fashing Field, Atascosa County, Texas
(Chapter XI). See also Oligocene globigerinids, Horowitz and Potter, 1971, PI. 67.
Thin section, x 90