Garra Formation Brachiopods 1, Wellington Area (Devonian of Australia)

Where: New South Wales, Australia (32.6° S, 149.0° E: paleocoordinates 9.0° S, 174.0° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Garra Formation, Pragian (410.8 - 407.6 Ma)

• Authors interpret the formation as spanning mid and late Lochkovian to Pragian, based on conodonts and Brachiopods, with the conclusion that "a mid Lochkovian to Pragian age is reasonable for the lowest two-thirds of the formation." The material here is largely from the middle third. Strusz et al. (1999--PBDB ref.7152) conclude, based on brachiopods, that the material reported here is Pragian. Farrell (1992--PBDB ref. 7169), after studying the Garra in the type area to the south, concludes that the formation is diachronous, being younger here in the Wellington area, mainly Pragian sulcatus Zone, and late Lochkovian in the type area.

• formation-level stratigraphic resolution

Environment/lithology: marine; grainstone and calcareous shale

• "The Garra limestones are the product of relatively shallow water deposition; the lower approximately one-third of the formation represents a progressive transgressive sequence, the middle portion is the product of still-sand and gradual infilling, and the upper one-third represents progressive shallowing to supratidal conditions."
• Lenz and Johnson basically just refer to "pure limestones," from which this material comes Strusz (1965, ref. 7170) mentions a broader suite of lithologies for the formation as a whole, as does Farrell (1992, ref. 7169). These are predominantly calcareous shale and detrital limestone, interspersed with biohermal and biostromal deposits. The detrial limestones include many types, but are mainly calcarenites. In some places there are algal limestones, pellet or oolite calcarenties.

Size class: macrofossils

Preservation: replaced with silica

Collection methods: Faunal list given by authors in terms of composite section rather than individual sections. Numbers of specimens given for numerous individual collections in terms of meters above base of composite section. All collections reported are from between 500 m and 850 m in the composite section (essentially the middle third). I have combined these.

Primary reference: A. C. Lenz and B. D. Johnson. 1985. Brachiopods of the Garra Formation (Lower Devonian), Wellington area, New South Wales, Australia: Orthida, Strophomenida, Pentamerida. Palaeontographica Abteilung A 188(1-3):35-70 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 25695: authorized by Michael Foote, entered by Michael Foote on 23.09.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

• Orthida, Strophomenida, and Pentamerida only.
unclassified
  -
Strophomenata
 Strophomenida - Sowerbyellidae
Plectodonta bipartita Chapman 1913
 Strophomenida - Chonetidae
? Devonochonetes sp. Muir-Wood 1962
sp. 1
 Strophomenida -
 Strophomenida - Strophonellidae
"? Strophoprion cf. podolica" = Strophonella
"? Strophoprion cf. podolica" = Strophonella
 Strophomenida - Leptostrophiidae
 Strophomenida - Douvillinidae
 Strophomenida - Rafinesquinidae
 Orthotetida - Areostrophiidae
Rhynchonellata
 Pentamerida - Gypidulidae
 Orthida - Hesperorthidae
 Orthida - Dalmanellidae
 Orthida - Rhipidomellidae
 Orthida - Mystrophoridae
 Orthida - Draboviidae
 Orthida - Schizophoriidae
 Spiriferida -
 Protorthida - Skenidiidae