JWHall #215, Brown Co., MN (Cretaceous of the United States)

Where: Brown County, Minnesota (44.2° N, 95.0° W: paleocoordinates 41.7° N, 55.9° W)

• coordinate based on political unit

When: Ostrander Member (Windrow Formation), Cenomanian (100.5 - 93.9 Ma)

• bed-level stratigraphic resolution

Environment/lithology: channel lag

• This sample comes from reworked material which filled a Cretaceous stream that cut through the Northwest corner of nonmarine lacustrine and lignite deposits.
• Typical Ostrander deposits occur to the East and consists of fine-grained, loosely consolidated gravels. The local deposits are mostly nonmarine fluvial, lacustrine, and deltaic origins.

Size class: microfossils

Preservation: original sporopollenin

Collection methods: bulk, chemical, sieve,

• Samples were processed and picked.

Primary reference: J. W. Hall and N. M. Peake. 1968. Megaspore assemblages in the Cretaceous of Minnesota. Micropaleontology 14(4):456-464 [R. Lupia/T. Naeher/T. Naeher]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 31945: authorized by Rick Lupia, entered by Tiffany Naeher on 29.05.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Orthothecimorpha
 Circothecida -
Costatheca sp.
Polypodiopsida
  - Marsileaceae
Molaspora rugosa
 Salviniales - Polypodiidae
Ariadnaesporites varius, cf. Azolla sp.
Ariadnaesporites varius
male and female
cf. Azolla sp. Lamarck 1783
Pteridopsida
 Marsileales -
Arcellites disciformis
Spermatites
  -
Spermatites sp.
Spermatites sp. Miner 1935
Lycopodiopsida
 Isoetales -
Minerisporites mirabilis
Rhynchonellata
 Terebratulida - Terebrataliidae
"Thomsonia dakotaensis" = Coptothyris
"Thomsonia dakotaensis" = Coptothyris
Tenellisporites
  -
Tenellisporites spinatus