ammonites
Upper Beds in Mulzer Brothers Quarry Section (Carboniferous of the United States)

Where: Crawford County, Indiana (38.4° N, 86.6° W: paleocoordinates 11.2° S, 26.9° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Glen Dean Limestone Formation, Pendleian (326.4 - 318.1 Ma)

• detailed stratigraphic sections have been described by Perry and Smith (1958, p. 97-100); fenestrate bryozoans are especially abundant on bedding planes in the upper portion of the Glen Dean

•JA: the Glen Dean is upper middle Chesterian = Pendleian

• group of beds-level stratigraphic resolution

Environment/lithology: marine; argillaceous, calcareous limestone and shale

• At the above localities fenestrate bryozoans are especially abundant on bedding planes of argillaceous limestone and calcareous shale beds in the upper part of the formation; fissile dark-gray shale and siltstone in the upper portion of the Glen Dean generally lack fenestrate bryozoans. The upper surface of the lower part of the Glen Dean, characterized by thick and massive limestone beds, commonly displays fenestrate bryozoans. Thick-bedded and massive strata in the lower Glen Dean contain conspicuously fewer specimens than beds in the upper part of the formation; further, forms in the lower Glen Dean are most difficult to collect and to extricate from the surrounding matrix for study.
• argillaceous limestone and calcareous shale beds

Size class: macrofossils

Collection methods: All identified specimens are in the collections of the Indiana Geological Survey, Bloomington, Indiana

Primary reference: J. Utgaard. 1961. Fenestrate Bryozoans from the Glen Dean Limestone (Middle Chester) of Southern Indiana. unpublished MA thesis, Indiana University 1-50 [A. Miller/D. Carlson] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 91022: authorized by John Alroy, entered by John Alroy on 31.08.2009

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)