Johnson Quarry, Iren Dabasu (Cretaceous to of China)

Also known as SCDP site 1, site K, AMNH quarry 141, Johnson's Quarry

Where: Nei Mongol, China (43.7° N, 112.2° E: paleocoordinates 43.0° N, 100.8° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Iren Dabasu Formation, Middle Campanian to Middle Campanian (83.5 - 70.6 Ma)

• The Iren Dabasu Formation is Middle–Late Campanian according to Xing et al. 2012

• bed-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; lithology not reported

Size class: macrofossils

Collected by A. F. Johnson in 1922-1928; reposited in the AMNH

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

• probably also visited by 1959 Sino-Soviet Paleontological Expedition

Primary reference: H. F. Osborn. 1922. Discovery of Cretaceous and older Tertiary strata in Mongolia. Science 56(1446):291-293 [M. Carrano/M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 48933: authorized by Matthew Carrano, entered by Matthew Carrano on 04.04.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

"Pelecypoda indet." = Bivalvia1
"Pelecypoda indet." = Bivalvia1 Linnaeus 1758 clam
 Testudines - Trionychidae
Trionychidae indet.1 Gray 1825 softshell turtle
 Saurischia -
Saurischia indet.1 saurischian
 Avetheropoda - Ornithomimidae
"Ornithomimus asiaticus" = Archaeornithomimus asiaticus2
"Ornithomimus asiaticus" = Archaeornithomimus asiaticus2 Gilmore 1933 ornithomimid
 Ornithischia -
Ornithischia indet.1 ornithischian
 Neornithischia -
Bactrosaurus johnsoni n. gen. n. sp.2 Gilmore 1933 bird foot dinosaur
AMNH 6553, 6365, 6366, 6577
Bactrosaurus johnsoni3 Gilmore 1933 bird foot dinosaur
 Loricata -
Crocodylia indet.1 crocodilian