Buchan Group

Buchan Group
Buchan Group
Stratigraphic range: Early Devonian (Pragian-Emsian) 413.02–393.47 Ma PreꞒ Ꞓ O S D C P T J K Pg N Lo. P Emsian Ei. Gi. Fras. Fam.
Type	Geologic group
Sub-units	Buchan Caves Limestone, Taravale Formation, Murrindal Limestone
Overlies	Snowy River Volcanics
Thickness	700–1,100 m (2,300–3,600 ft)
Lithology
Primary	Limestone
Other	Mudstone, shale, marl (Taravale)
Location
Location	Near Buchan, Victoria
Coordinates	37°29′44.88″S 148°9′47.16″E / 37.4958000°S 148.1631000°E
Region	Victoria
Country	Australia
	Buchan Group (Australia) Buchan Group (Victoria)

The Buchan Group is a group of Early Devonian (Pragian–Emsian) aged strata located near Buchan, Victoria in Australia. It consists of three formations; the oldest Buchan Caves Limestone, the Taravale Formation, and the youngest Murrindal Limestone, which consists of the members McLarty (McL) and Rocky Camp (ROC).

Strata

As stated above, the Buchan Group is made up of three formations:

Buchan Caves Limestone: The Buchan Caves Limestone consists of a dark-gray limestone, increasing fossiliferous from base to top. This represents the shift from peritidal, regular marine shelf to more open shelf and biohemal environments.
Taravale Formation: The Taravale Formation, with one sole primary bioherm in the south, is made up of mudstones, shales, marls and nodular limestone. Deposited in deep marine environments, these sediments document detrital influx and reduced carbonate production proportionately. The formation laterally and vertically grades into the Murrindal Limestone, which overlies it. A unit of the Taravale, the Pyramids Member, stretches beneth the Murrindal.
Murrindal Limestone: The Murrindal Limestone, measuring up to 330 meters in thickness, is a shallowing-upward shelf to lagoonal sequence possessing plentiful bioherms and mounds. It represents a final transgression and final drowning of shallow-water communities, which ceased bioherm construction. This has resulted in the slope marl deposition of the Taravale Formation. It consists of two members:
- McLarty Member (McL): The McLarty Member, the lower strata, possesses well-bedded limestones with a dark colouration, and possesses rich fossiliferous beds to the east, which is equivalent to a fore-reef facies, and to the west the beds are poorer in fossils and away from the bioherms.
- Rocky Camp Member (ROC): The Rocky Camp Member, the upper strata, is a discontinuous, biohermal limestone unit with a thickness up to 600m, lies in the north of the basin and is paler in colouration, poorly-bedded, fossiliferous and is home to mud-mound facies. This site, which has been quarried, hosts the two southerly lens and has among the best exposures of sedimentary facies. There are two forms of accumulations which form the basis of the ROC, a small bioherm facies, and a mud-mound facies. The former, only <200m in diameter, is present north of the Rocky Camp and Dally's hills, and hosts thin units of fossiliferous, bioclastic and pelloidal grainstone to packstone which seems to be absent in stromatactis.

Geology

Preserved in the Buchan-Murrindal Synclinorium, a north-trending basin, the Buchan Group was deposited in a marine environment. It is subdivided into three formations: Buchan Caves Limestone, Taravale Formation, and Murrindal Limestone. Within the Spring Creek Member, at the base of the Buchan Caves Limestone, is the transition from terrestrial volcanism to marine carbonate sedimentation. Overlying the Spring Creek Member is about 40 meters of heavily dolomitized limestone which harbour few recognizable fossils.

In the Buchan Caves Limestone, the upper portion shifts to increasing argillaceous (clay) until it becomes lime mudstone of the Pyramids Marlstone Member, the lowermost and overlying strata of the Taravale Formation. This marks a transition from an open-marine deposition to deeper water sedimentation. Within the northern region of the synclinorium, said deep-water sedimentation gives way to the more shallow marine deposition, which marks the Murrindal Limestone. A total thickness of 1,100 meters of the Buchan Group is preserved in the southern part of the synclinorium, while in the north it is closer to 700 meters.

In addition to numerous species of brachiopods and conodonts, the Buchan Group hosts several placoderm taxa, such as Arenipiscis and Buchanosteus, as well as the fish Ligulalepis, that are similar to those of the Murrumbidgee Group, another Early Devonian group of Burrinjuck, New South Wales. This indicates that the two strata were in the process of deposition at approximately the same time, and that these fish lived throughout the region.

Invertebrates

Brachiopods of the Buchan Group
Genus	Species	Formation	Clade	Images
Ambocoelia	A. sp. aff. A. runnegari	Murrindal (McL)	Spiriferida, Ambocoeliidae
Atryparia	A. penelopeae	Murrindal (McL & ROC)	Atrypida, Atrypidae
Aulacella	A. philipi		Orthida, Rhipidomellidae
Bidigitus	B. murrindalensis		Orthida, Dalmanellidae
Biernatium	B. catastum	Murrindal (McL)	Orthida, Mystrophoridae
Buchanathyris	B. westoni	Murrindal (McL & ROC)	Athyridida, Athyrididae
Coelospira	C. dayi	Murrindal (McL)	Athyridida, Anoplothecidae
Craniops	C. australis	Murrindal (McL & ROC)	Craniopsida, Craniopsidae
Cymostrophia	C. (Protocymostrophia) dickinsi		Strophomenida, Douvillinidae
Cyrtina	C. wellingtonensis		Spiriferinida, Cyrtinidae
Delthyris	?D. sp.	Murrindal (McL)	Spiriferida, Delthyrididae
Dolerorthis	D. sp.	Murrindal (McL & ROC)	Orthida, Hesperorthidae	Fossil of Dolerorthis.
Eoglossinotoechia	E. linki		Rhynchonellida, Glossinotoechiidae
Eoschuchertella	E. murphyi		Orthotetida, Areostrophiidae
gen. indet.	sp. indet.	Murrindal (ROC)	Orthida, Hesperorthidae
Howellella	H. (H.) textilis	Murrindal (McL & ROC)	Spiriferida, Delthyrididae
Howittia	H. howitti	Murrindal (McL & ROC)	Spiriferida, Cyrtinopsidae
Johnsonetes	J. australis	Murrindal (McL & ROC)	Productida, Strophochonetidae
Johnsonetes	J. sp. cf. J. culleni	Murrindal (ROC)	Productida, Strophochonetidae
Malurostrophia	M. sp. cf. M. flabellicauda	Murrindal (McL & ROC)	Strophomenida, Douvillinidae
Mesoleptostrophia	M. (Paraleptostrophia) clarkei		Strophomenida, Leptostrophiidae
Micidus	?M. glaber		Terebratulida, Meganteridae
Micidus	M. shandkyddi		Terebratulida, Meganteridae
Nadiastrophia	N. patmorei		Strophomenida, Douvillinidae
Notoleptaena	N. adamantea		Strophomenida, Rafinesquinidae
Nucleospira	N. sp.	Murrindal (McL)	Athyridida, Nucleospiridae
Opsiconidion	O. arcticon	Murrindal (ROC)	Acrotretida, Biernatidae
Opsiconidion	O. sp. cf. O. aldridgei	Murrindal (ROC)	Acrotretida, Biernatidae
Prokopia	P. hillae	Murrindal (McL & ROC)	Orthida, Dalmanellidae
Pugnax	‘P.’ oepiki		Rhynchonellida, Pugnacidae
Resserella	R. careyi		Orthida, Dalmanellidae
Spinella	S. buchanensis buchanensis		Spiriferida, Spinellidae
Spinella	S. yassensis		Spiriferida, Spinellidae
Tyersella	T. spedeni		Orthida, Dalmanellidae
Variatrypa	V. (V.) erectirostris		Atrypida, Atrypidae

Rugose corals of the Buchan Group
Genus	Species	Strata	Clade	Images
Acanthophyllum	A. aequiseptatum	Buchan Caves	Rugosa, Acanthophyllidae
	A. aff. clermontense	Murrindal (ROC)
	A. sp.	Buchan Caves
Campophyllum	'C.' recessum	Buchan Caves	Rugosa, Caniniidae
Disphyllum	D. angulare	Murrindal (McL)	Rugosa, Disphyllidae
Disphyllum	D. speleanum	Buchan Caves	Rugosa, Disphyllidae
Lyrielasma	L. aff. floriforme	Murrindal	Rugosa, Acanthophyllidae
Metriophyllum	M. erisma	Murrindal (McL)	Rugosa, Metriophyllidae
Pseudamplexus	P. ?princeps	Buchan Caves	Rugosa, Mucophyllidae
Spongophyllum	S. murale	Murrindal (McL) (uncertain)	Rugosa, Spongophyllidae
Syringaxon	S. radiatum	Murrindal (McL)	Rugosa, Syringaxonidae
Xystriphyllum	X. mitchelli	Murrindal (ROC)	Rugosa, Acanthophyllidae

Stromatoporoids of the Buchan Group
Genus	Species	Strata	Clade	Images
Actinostroma	A. compactum	Buchan Caves Murrindal (ROC)
	A. contortum	Buchan Caves Murrindal (ROC)
	A. stellulatum var. distans	Buchan Caves
Clathrodictyon	C. clarum	Buchan Caves Murrindal (ROC)
	C. confertum	Buchan Caves
	C. convictum	Buchan Caves
	C. convictum var. delicatula	Buchan Caves Murrindal (ROC)
	C. regulare	Buchan Caves
Hermatostroma	H. episcopale	Buchan Caves
Hermatostroma	H. episcopale var. buchanensis
Stromatopora	S. aff. S. foveolata	Murrindal (ROC)
	S. concentrica	Buchan Caves Murrindal (ROC)
	S. concentrica var. colliculata	Buchan Caves Murrindal (ROC)
	S. hupschii	Murrindal (ROC)

Tabulate corals of the Buchan Group
Genus	Species	Strata	Clade	Images
Alveolites	A. stamineus	Murrindal	Tabulata, Alveolitidae
Alveolites	A. sp.	Murrindal (ROC)	Tabulata, Alveolitidae
Aulopora	A. cf. conglomerata	Buchan Caves	Tabulata, Auloporidae	Specimen of A. sp.
Coenites	'C.' expansus	Murrindal (ROC)	Tabulata, Coenitidae	Specimen of the related Coenites laqueata.
Favosites	F. bryani	Unknown	Tabulata, Favositidae	Specimen of F. sp.
	F. nitidus	Murrindal (ROC)
	F. pluteus	Murrindal (ROC)
	F. stelliformis	Unknown
Gephuropora	G. duni	Murrindal	Tabulata, Favositidae
~~Ligulodictyum~~ Pleurodictyum	P. sp.	Taravale	Tabulata, Favositidae	Specimen of the related P. americanum.
Roemeria	R. ocellata	Murrindal (ROC)	Tabulata, Syringoporidae
Roemeria	R. sp.	Buchan Caves	Tabulata, Syringoporidae
Syringopora	S. flaccida	Buchan Caves	Tabulata, Syringoporidae	Specimen of S. sp.
Syringopora	S. sp.	Murrindal (ROC)	Tabulata, Syringoporidae	Specimen of S. sp.
Thamnopora	T. alterivalis	Buchan Caves Murrindal (McL)	Tabulata, Favositidae
	T. angulata	Murrindal (ROC)
	T. tumulosa	Murrindal (McL)

Vertebrates

Conodonts of the Buchan Group
Genus	Species	Strata	Clade	Images
Belodella	B. sp. cf. B. devonica	Murrindal (McL & ROC)	Proconodontida, Belodellidae
	B. resima	Buchan Caves Murrindal (McL & ROC)
	B. triangularis	Buchan Caves Murrindal (McL & ROC)
Drepanodus	D. A	Murrindal (McL)	Protopanderodontida, Distacodontidae
Drepanodus	D. B	Murrindal (McL)	Protopanderodontida, Distacodontidae
Eognathodus	E. linearis	Buchan Caves	Ozarkodinida, Polygnathacea incertae sedis
Hindeodella	H. equidentala	Buchan Caves Murrindal (McL & ROC)	Ozarkodinida, Coleodontidae
	H. priscilla	Buchan Caves Murrindal (McL & ROC)
	H. A	Murrindal (McL)
	H. B	Murrindal (ROC)
Lonchodina	L. murrindalensis	Murrindal (McL)	Ozarkodinida, Coleodontidae
Lonchodina	L. sp.	Buchan Caves Murrindal (McL)	Ozarkodinida, Coleodontidae
Neoprioniodus	N. bicurvatus	Buchan Caves Murrindal (McL & ROC)	Uncertain
Ozarkodina	O. alternatus	Buchan Caves	Ozarkodinida, Spathognathodontidae
	O. extensus lacertosus	Murrindal (McL)
	O. denckmanni	Buchan Caves Murrindal (McL & ROC)
	O. media	Murrindal (McL)
	O. sp. cf. O. jageri	Buchan Caves
	?O. sp.	Buchan Caves
Panderodus	P. acostatus	Buchan Caves Murrindal (McL & ROC)	Panderodontida, Panderodontidae	Restoration of P. unicostatus.
	P. unicostatus
	P. valgus
	P. sp. cf. P. recurvatus	Buchan Caves Murrindal (McL)
Plectodina	P. excavata	Murrindal (McL)	Uncertain
	P. inconstans	Buchan Caves Murrindal (McL)
	P. symmetrica pinnula	Buchan Caves
	P. sp. cf. P. inconstans	Buchan Caves Murrindal (McL)
	P. sp.	Buchan Caves
Polygnathus	P. linguiformis	Taravale Murrindal (McL & ROC)	Ozarkodinida, Polygnathidae
Roundya	R. perbona	Murrindal (McL)	Conodonta, incertae sedis
Spathognathodus	S. exiguus	Murrindal (McL)	Ozarkodinida, Spathognathodontidae
	S. inclinatus inclinatus	Murrindal (McL)
	S. steinhornensis buchanensis	Buchan Caves Taravale Murrindal (McL & ROC)
	S. sp.	Buchan Caves

Placoderms of the Buchan Group
Genus	Species	Strata	Clade	Images
Arenipiscis	A. westolli	Murrindal (?McL)	Arthrodira, Buchanosteidae	Restoration of A. westolli.
Buchanosteus	B. confertituberculatus	Unknown	Arthrodira, Buchanosteidae	B. confertituberculatus reconstruction.
Buchanosteus	B. sp.	Buchan Caves Taravale Murrindal	Arthrodira, Buchanosteidae	B. confertituberculatus reconstruction.
Errolosteus	cf. E. goodradigbeensis	Murrindal (McL)	Arthrodira, Buchanosteidae	E. goodradigbeensis reconstruction.
Goodradigbeeon	G. australianum	Buchan Caves Taravale	Arthrodira, Buchanosteidae	A reconstruction of G. australianum.
Murrindalaspis	M. bairdi	Murrindal (ROC)	Acanthothoraci, Weejasperaspididae	Cropped image showing a restoration of M. wallacei.
	M. wallacei	Murrindal (McL)
	M. sp.	Taravale
Ohioaspis	O. sp.	Murrindal	Incertae sedis (Rhenanida?)
Taemasosteus	T. maclartiensis	Murrindal (McL & ROC)	Arthrodira, Buchanosteidae	Restoration of T. novaustrocambricus.
Wijdeaspis	W. warrooensis	Murrindal (McL)	Petalichthyida, incertae sedis
gen. indet.	sp. indet.	Murrindal (ROC)	Euarthrodira, incertae sedis

Chondrichthyans of the Buchan Group
Genus	Species	Strata	Clade	Images
Cheiracanthoides	C. sp. cf. C. comptus	Buchan Caves Taravale Murrindal	Climatiiformes,Climatiidae
Cheiracanthoides	C. sp. cf. C. wangi	Taravale Murrindal	Climatiiformes,Climatiidae
Gomphonchus	?G. bongongensis	Buchan Caves Taravale Murrindal	Ischnacanthiformes, Ischnacanthidae
Nostolepis	"N." guangxiensis	Buchan Caves Taravale Murrindal	Climatiiformes, Climatiidae	Reconstruction of Nostolepis.
Nostolepis	cf. N. sp.	Taravale	Climatiiformes, Climatiidae	Reconstruction of Nostolepis.
Nostolepoides	N. platymarginata	Buchan Caves Taravale Murrindal	Climatiiformes, Climatiidae
Rhadinacanthus	?R. sp.	Buchan Caves Murrindal	Diplacanthiformes, Diplacanthidae

Other vertebrates of the Buchan Group
Genus	Species	Strata	Clade	Images
Ligulalepis	L. toombsi	Taravale	Osteichthyes, incertae sedis	Life reconstruction of L. toombsi, based on a skull.
Turinia	sp. cf. T. australiensis	Buchan Caves	Thelodontiformes, Turiniidae	Reconstruction of T. pagei.
gen. indet.	sp. indet.	Taravale Murrindal	Onychodontiformes, incertae sedis

References

1 2 3 4 Arne, D. C.; Cromie, P. W.; Webb, J. A.; Richards, J. R. "The genesis of Pb‐Zn sulphide occurrences in the Lower Devonian Buchan Group, Victoria". Australian Journal of Earth Sciences. 41 (2): 75–90. doi:10.1080/08120099408728117. ISSN 0812-0099.
1 2 Plusquellec, Yves (2015-12-08). "First record of the tabulate coral " Ligulodictyum " in the early Emsian of Victoria (Australia), with additional data on Australian Ligulodictyum sensu lato". Proceedings of the Royal Society of Victoria. 127 (2): 17–27. doi:10.1071/RS15015. ISSN 0035-9211.
↑ Tosolini, A.-M.P.; Wallace, M.W.; Gallagher, S.J. "Shallow water mud-mounds of the Early Devonian Buchan Group, East Gippsland, Australia". Sedimentary Geology. 281: 208–221. doi:10.1016/j.sedgeo.2012.09.007.
1 2 Arne, D. C.; Cromie, P. W.; Webb, J. A.; Richards, J. R. (1993). "The genesis of Pb‐Zn sulphide occurrences in the Lower Devonian Buchan Group, Victoria". Australian Journal of Earth Sciences. 41 (2): 75–90. doi:10.1080/08120099408728117. ISSN 0812-0099.
↑ Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Buchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. 115 (1–2): 7–26. ISSN 0035-9211.
↑ Long, J. A. (1984). "New placoderm fishes from the Early Devonian Buchan Group, eastern Victoria". Proceedings of the Royal Society of Victoria. 96 (4): 173–186. ISSN 0035-9211.
↑ Valentine, James L. (2005). "Highly Silicified Early Devonian (Emsian) brachiopods from the Murrindal Limestone, Buchan, eastern Victoria". Proceedings of The Royal Society of Victoria. 117 (2): 199–264.
↑ Guo, W.; Sun, Y.; Baliński, A. (2015). Parallel evolution of jugal structures in Devonian athyridide brachiopods. Palaeontology, 58, 171-182.
↑ Waterhouse, J. B. (John Bruce) (2016-01-01). "On the evolution and classification of Spiriferida (Brachiopoda) / J. B. Waterhouse". https://digitalnz.org/records/55470025. Oamaru, New Zealand : [J. B. Waterhouse], 30 November, 2016. Retrieved 2026-10-21. {{cite web}}: External link in |website= (help)
1 2 Hill, Dorothy (1950). "Middle Devonian corals from the Buchan district, Victoria". Proceedings of The Royal Society of Victoria. 62 (2): 137–164.
↑ Ripper, Elizabeth A. (1937). "On the Stromatoporoids of the Buchan District, Victoria". Proceedings of The Royal Society of Victoria. 50 (1): 11–45.
↑ Philip, G. M. (1966). "Lower Devonian Conodonts from the Buchan Group, Eastern Victoria". Micropaleontology. 12 (4): 441. doi:10.2307/1484789.
1 2 3 4 5 6 7 8 Long, J. A. (1984). "New placoderm fishes from the Early Devonian Buchan Group, eastern Victoria". Proceedings of the Royal Society of Victoria. 96 (4): 173–186. ISSN 0035-9211.
1 2 3 4 5 6 7 Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Buchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. 115 (1–2): 7–26. ISSN 0035-9211.
↑ Basden, Alison; Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Bucchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. New series. 115 (1/2): 7––26.

[Reference-1-1] 1 2 3 4 Arne, D. C.; Cromie, P. W.; Webb, J. A.; Richards, J. R. "The genesis of Pb‐Zn sulphide occurrences in the Lower Devonian Buchan Group, Victoria". Australian Journal of Earth Sciences. 41 (2): 75–90. doi:10.1080/08120099408728117. ISSN 0812-0099.

[Reference-5-2] 1 2 Plusquellec, Yves (2015-12-08). "First record of the tabulate coral " Ligulodictyum " in the early Emsian of Victoria (Australia), with additional data on Australian Ligulodictyum sensu lato". Proceedings of the Royal Society of Victoria. 127 (2): 17–27. doi:10.1071/RS15015. ISSN 0035-9211.

[Reference-4-3] Tosolini, A.-M.P.; Wallace, M.W.; Gallagher, S.J. "Shallow water mud-mounds of the Early Devonian Buchan Group, East Gippsland, Australia". Sedimentary Geology. 281: 208–221. doi:10.1016/j.sedgeo.2012.09.007.

[Reference-12-4] 1 2 Arne, D. C.; Cromie, P. W.; Webb, J. A.; Richards, J. R. (1993). "The genesis of Pb‐Zn sulphide occurrences in the Lower Devonian Buchan Group, Victoria". Australian Journal of Earth Sciences. 41 (2): 75–90. doi:10.1080/08120099408728117. ISSN 0812-0099.

[Reference-32-5] Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Buchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. 115 (1–2): 7–26. ISSN 0035-9211.

[Reference-22-6] Long, J. A. (1984). "New placoderm fishes from the Early Devonian Buchan Group, eastern Victoria". Proceedings of the Royal Society of Victoria. 96 (4): 173–186. ISSN 0035-9211.

[7] Valentine, James L. (2005). "Highly Silicified Early Devonian (Emsian) brachiopods from the Murrindal Limestone, Buchan, eastern Victoria". Proceedings of The Royal Society of Victoria. 117 (2): 199–264.

[8] Guo, W.; Sun, Y.; Baliński, A. (2015). Parallel evolution of jugal structures in Devonian athyridide brachiopods. Palaeontology, 58, 171-182.

[Reference-6-9] Waterhouse, J. B. (John Bruce) (2016-01-01). "On the evolution and classification of Spiriferida (Brachiopoda) / J. B. Waterhouse". https://digitalnz.org/records/55470025. Oamaru, New Zealand : [J. B. Waterhouse], 30 November, 2016. Retrieved 2026-10-21. {{cite web}}: External link in |website= (help)

[Journal-1-10] 1 2 Hill, Dorothy (1950). "Middle Devonian corals from the Buchan district, Victoria". Proceedings of The Royal Society of Victoria. 62 (2): 137–164.

[11] Ripper, Elizabeth A. (1937). "On the Stromatoporoids of the Buchan District, Victoria". Proceedings of The Royal Society of Victoria. 50 (1): 11–45.

[12] Philip, G. M. (1966). "Lower Devonian Conodonts from the Buchan Group, Eastern Victoria". Micropaleontology. 12 (4): 441. doi:10.2307/1484789.

[Reference-2-13] 1 2 3 4 5 6 7 8 Long, J. A. (1984). "New placoderm fishes from the Early Devonian Buchan Group, eastern Victoria". Proceedings of the Royal Society of Victoria. 96 (4): 173–186. ISSN 0035-9211.

[Reference-3-14] 1 2 3 4 5 6 7 Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Buchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. 115 (1–2): 7–26. ISSN 0035-9211.

[:13-15] Basden, Alison; Basden, Alison (2003). "Early Devonian (Emsian) vertebrate microremains from the Bucchan Group, Victoria, Australia". Proceedings of the Royal Society of Victoria. New series. 115 (1/2): 7––26.