Yale Point, AZ (A5-30) (Cretaceous of the United States)

Where: Navajo County, Arizona (36.3° N, 109.8° W: paleocoordinates 39.5° N, 75.7° W)

• small collection-level geographic resolution

When: Watinoceras Ammonite zone, Mancos Shale Formation, Early/Lower Turonian (93.5 - 89.3 Ma)

• Bed horizon is the sample number not the lithologic unit number. The lithologic unit numbers that correspond to the sample numbers given can be found in reference for collection (Elder, 87).

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, gray, silty, calcareous shale

• Shale, medium olive gray, mod. well to well indurated, common gypsum, mod. to mod. well laminar.

Note: Section A5 constitutes interbedded limestones and shales, but this sedimentary structure is not reflected in the descriptions of each collection, as each is often a single bed, or a portion thereof.

Size class: macrofossils

Collection methods: bulk, mechanical,

• Bulk sample disaggregated in lab.

Primary reference: W. P. Elder. 1987. The paleoecology of the Cenomanian-Turonian (Cretaceous) stage boundary extinctions at Black Mesa, Arizona. Palaios 2(1):24-40 [C. Marshall/S. Low/A. Clement]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 3215: authorized by Charles Marshall, entered by Sofy Low on 27.07.1999

Creative Commons license: CC BY (attribution)

Taxonomic list

Lingulata
 Discinida - Disciniidae
Discinisca sp. Gray 1840
Cephalopoda
 Ammonoidea -
Ammonoidea indet. ammonite
originally entered as "Ammonite"; changed by JA 30.6.04
Gastropoda
 Sorbeoconcha - Aporrhaidae
Drepanocheilus ruidium snail
originally entered as "Drepanochilus ruidium"
 Neogastropoda - Fasciolariidae
? Bellifusus sp. Stephenson 1941 snail
originally entered as "Bellifusus(?) sp."
Bivalvia
  -
Bivalvia indet. Linnaeus 1758 clam
originally entered as "Infaunal bivalve"
 Lucinida - Lucinidae
Lucina sp. Bruguière 1797 clam
 Pectinida - Entoliidae
Entolium sp. Meek 1865 scallop
 Myalinida - Inoceramidae
Inoceramidae indet. Giebel 1852 clam
originally entered as "informal Inoceramid indet."; changed by JA 21.2.07
Mytiloides sp. n. sp. Brongniart 1822 clam
"n. sp. A" - originally entered as "Mytiloides n. sp. A"
Mytiloides aff. duplicostasus clam
"aff. m. duplicostasus" - originally entered as "Mytiloides aff. m. duplicostasus"
Mytiloides opalensis Böse 1923 clam