ammonites
Hatch Ranch, Piedmont Butte (Jurassic to of the United States)

Also known as Barosaurus type, SDSM V9140

Where: Meade County, South Dakota (44.2° N, 103.4° W: paleocoordinates 39.4° N, 49.2° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Morrison Formation, Kimmeridgian to Kimmeridgian (155.7 - 145.5 Ma)

• Several meters above the Unkpapa Sandston Member; Zone 5; Morrison of S. Dakota sometimes referred to as the "Beulah shales"

• bed-level stratigraphic resolution

Environment/lithology: wet floodplain; ferruginous, black, gray, green, silty, calcareous claystone

• "Poorly drained floodplain - Type 1" Wet areas of floodplain; ponds; near channel or out on plain
• "green-gray claystone", but described by Marsh as blue and by Wieland as black. Lull 1919 analysis: "The rock consists of clay with the very finest silt, the grains of which are probably not more than .01 mm in diameter. A fine grit was discernible in the clay, and an appreciable content of lime, as shown by a vigorous effervescence with acid. The gray clay shows occasional rusty stains from recent weathering, probably due to the presence of ferrous carbonate."

Size classes: macrofossils, mesofossils

Collected by E. R. Ellerman, O. C. Marsh, J. B. Hatcher, G. R. Wieland in 1889, 1898; reposited in the YPM

Collection methods: quarrying, surface (in situ), mechanical,

• collected by Marsh & Hatcher, 1889; Wieland 1898. Discovered from E. R. Ellerman on land belonging to Rachel Hatch.

Primary reference: O. C. Marsh. 1890. Description of new dinosaurian reptiles. The American Journal of Science, series 3 39:81-86 [M. Carrano/M. Carrano/M. Carrano] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 57905: authorized by Matt Carrano, entered by Kaitlin Maguire on 05.01.2006