Dillingham - unnamed collection (McRoberts & Blodgett, 2000) (Triassic of the United States)

Also known as Unnamed collection

Where: Dillingham County, Alaska (60.9° N, 157.4° W: paleocoordinates 7.8° N, 80.4° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Holitna Group, Norian (228.0 - 208.5 Ma)

• Lowest exposed unit in succession. No formal stratigraphic name has been applied to the Triassic rocks of the Taylor Mountain D-2 and D-3 quadrangles. The term "Holitna Group" has been suggested to be too broadly defined (includes all Paleozoic carvonates in the Holitna River section). LePain and others (2000) designated these strata as Tzrlc (silty limestone and chert) on their geological map. Total thickness of Triassic rocks in section is unknown, although a minimum thickness of 300 m is estimated.

• bed-level stratigraphic resolution

Environment/lithology: marine; gray, calcareous packstone

• From Farewell terrane of southwestern and west-central Alaska. Farewell terrane is of early and middle Paleozoic age and probably originated as a rifted continental margin sequence derived from the Siberian continent by a Devopnian or slightly later rifting event. Deepening upward succession
• Consists of distinctive white to light gray lime packstone.

Size class: macrofossils

Preservation: recrystallized, replaced with silica

Collection methods: quarrying,

• Collected by R.B. Blodgett (1984, 1999). Field #84RB32, 99RB35. Contains scleractinian corals, indeterminate hydrozoans, and inozoan sponges. Collections deposited in U of Alaska Museum in Fairbanks

Primary reference: C. A. McRoberts and R. B. Blodgett. 2000. Late Triassic (Norian) mollusks from the Taylor Mountains quadrangle, southwestern Alaska. United States Geological Survey Professional Paper 1662:55-67 [A. Miller/A. Hendy/S. Kolbe]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 39897: authorized by Austin Hendy, entered by Austin Hendy on 11.06.2004, edited by Wolfgang Kiessling

Creative Commons license: CC BY (attribution)

Taxonomic list

• Only corals (identified by G.D. Stanley Jr (in Blodgett et al. 2000)
 Scleractinia - Procyclolitidae
Procyclolites sp. Frech 1890 stony coral
 Scleractinia - Astraeomorphidae
Astraeomorpha crassisepta Reuss 1854 stony coral
 Scleractinia - Reimaniphylliidae
? Distichophyllia cf. norica Frech 1890 stony coral
 Scleractinia - Margarophylliidae
 Scleractinia - Pamiroseriidae
"Rhaetiastraea cf. vesiculosa" = Crassistella vesiculosa, ? Pamiroseris meriani
"Rhaetiastraea cf. vesiculosa" = Crassistella vesiculosa Melnikova 1986 stony coral
? Pamiroseris meriani Stoppani 1858 stony coral