Mother's Day Quarry (Jurassic of the United States)

Also known as Mothers Day Site, MDQ, MT-1

Where: Carbon County, Montana (45.2° N, 108.8° W: paleocoordinates 40.5° N, 52.8° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Salt Wash Member (Morrison Formation), Kimmeridgian (157.3 - 152.1 Ma)

• bed-level stratigraphic resolution

Environment/lithology: crevasse splay; fine-grained, pebbly, intraclastic, brown, argillaceous, calcareous sandstone

• "a levee or overbank deposit"
• "a muddy fine-grained sandstone"; "The bone bed matrix consists of light brown very fine-grained sand and silt-to-clay sized particles. The matrix is composed primarily of quartz grains bound by calcareous cement but also includes trace amounts of feldspar...clay rip-up clasts and sparsely distributed pebbles and carbonate nodules occur as minor components of the bone bed...the MDQ deposit lacks definitive indicators of paleopedogenesis"

Size classes: macrofossils, mesofossils

Preservation: soft parts

Collected by MOR, CMC in 1994-2003

Collection methods: quarrying, mechanical,

• discovered by MOR crews, then worked by Cinicinnati Museum Center

Primary reference: C. E. Turner and F. Peterson. 1999. Biostratigraphy of dinosaurs in the Upper Jurassic Morrison Formation of the Western Interior, U.S.A. In D. D. Gillette (ed.), Vertebrate Paleontology in Utah, Utah Geological Survey Miscellaneous Publication 99-1:77-114 [M. Carrano/M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 69890: authorized by Matthew Carrano, entered by Matthew Carrano on 08.03.2007, edited by Jonathan Tennant

Creative Commons license: CC BY (attribution)

Taxonomic list

 Saurischia - Diplodocidae
Diplodocus sp.3 Marsh 1878 diplodocine
"Diplodocus or Barosaurus (not Apatosaurus)"
 Saurischia -
Theropoda indet.2 Marsh 1881 theropod
 Avetheropoda - Dromaeosauridae
Dromaeosauridae indet. Colbert and Russell 1969 coelurosaur
 Ornithischia - Stegosauridae
Stegosaurus sp.1 Marsh 1877 ornithischian