Early Cambrian and Older Trace Fossils from the Southern Cordillera of Canada

1972 ◽  
Vol 9 (1) ◽  
pp. 1-17 ◽  
Author(s):  
F. G. Young
Keyword(s):  
British Columbia ◽  
Marine Environment ◽  
Carbonate Rocks ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Older Age ◽  
Early Cambrian ◽  
Shallow Marine ◽  
Sedimentary Environments ◽  
Organic Life

Metazoan trace fossils of Early Cambrian and older age have been found in parts of the Gog, Cariboo, and Miette Groups of eastern British Columbia and western Alberta. Most of them occur in beds immediately below the zones containing the earliest Cambrian trilobites and archaeocyathids. These beds represent a variety of sedimentary environments, including the beach and littoral (Skolithos – facies), and shallow marine (Cruziana – facies) environments in the upper McNaughton Formation of the Gog Group: and a moderately deep marine environment in the Midas Formation of the Cariboo Group. Below these zones evidence of organic life is mainly restricted to stromatolites in carbonate rocks, and simple feeding-burrows in argillaceous silt-stones. A rare, but important trace fossil in this zone is a doubly furrowed trail, which is herein named Didymaulichnus miettensis (gen. et sp. nov.). This fossil indicates that metazoans existed before the Cambrian Period by a span of time represented by the net deposition of up to 2000 m of detrital sediments.

The type specimens (Middle Cambrian) of the trace fossil Archaeonossa Fenton and Fenton

1997 ◽  
Vol 34 (9) ◽  
pp. 1210-1219 ◽  
Author(s):  
Ellis L. Yochelson ◽  
Mikhail A. Fedonkin
Keyword(s):  
British Columbia ◽  
National Park ◽  
Original Description ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Type Material ◽  
Early Cambrian ◽  
Type Specimens ◽  
Middle Cambrian

The original description of Archaeonossa, from beds considered Early Cambrian but now dated as early Middle Cambrian, included at least two unrelated forms of trace fossils. The ichnogenus and the type ichnospecies are redefined, a lectotype is designated, and the type material is reiilustrated, along with topotype material from Yoho National Park, British Columbia. Although this trace fossil was originally attributed to movement by a gastropod, it is concluded, on the basis of restudy, that the type occurrence should not be used as evidence of activity by Gastropoda.

New occurrences of Oldhamia and other trace fossils in the Cambrian of the Yukon and Ellesmere Island, arctic Canada

1994 ◽  
Vol 31 (5) ◽  
pp. 767-782 ◽  
Author(s):  
H. J. Hofmann ◽  
M. P. Cecile ◽  
L. S. Lane
Keyword(s):  
North America ◽  
Western Europe ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Ellesmere Island ◽  
Early Cambrian ◽  
Arctic Canada ◽  
North Central ◽  
Middle Cambrian ◽  
New Occurrences

Trace fossil assemblages from green and maroon argillites at 34 localities in the British Mountains and Barn Mountains of northernmost Yukon, and 3 localities in the Grant Land Formation of northern Ellesmere Island contain abundant Planolites spp., Oldhamia curvata, Oldhamia flabellata, and Oldhamia radiata, and rare Oldhamia antiqua, Oldhamia? wattsi (n.comb.), Bergaueria hemispherica, Cochlichnus sp., Didymaulichnus? sp., Helminthoidichnites sp., Monomorphichnus sp., Protopaleodictyon sp., and Tuberculichnus? sp. Additionally, 11 new sites in the Selwyn Mountains of north-central Yukon have yielded an ichnofauna including Helminthorhaphe sp., O. curvata, O. flabellata, O. radiata, Plagiogmus? sp., Planolites spp., and unidentified small hemispherical traces. All these assemblages are interpreted as Early Cambrian to early Middle Cambrian, based on comparison with Oldhamia-bearing ichnofaunas of similar age in North America, Argentina, and western Europe, and on archaeocyathids and olenellids in overlying units.

The Fish River Subgroup in Namibia: stratigraphy, depositional environments and the Proterozoic–Cambrian boundary problem revisited

2005 ◽  
Vol 142 (5) ◽  
pp. 465-498 ◽  
Author(s):  
G. GEYER
Keyword(s):  
Trace Fossils ◽  
Global Scale ◽  
Depositional Environments ◽  
Trace Fossil ◽  
Braided River ◽  
Shallow Marine ◽  
Sequence Stratigraphic ◽  
Marine Habitats ◽  
Short Period ◽  
Distinct Sequence

The Fish River Subgroup of the Nama Group, southern Namibia, is restudied in terms of lithostratigraphy and depositional environment. The study is based on partly fine-scaled sections, particularly of the Nababis and Gross Aub Formation. The results are generally in accordance with earlier studies. However, braided river deposits appear to be less widely distributed in the studied area, and a considerable part of the formations of the middle and upper subgroup apparently were deposited under shallowest marine conditions including upper shore-face. Evidence comes partly from sedimentary features and facies distribution, and partly from trace fossils, particularly Skolithos and the characteristic Trichophycus pedum. Environmental conditions represented by layers with T. pedum suggest that the producer favoured shallow marine habitats and transgressive regimes. The successions represent two deepening-upward sequences, both starting as fluvial (braided river) systems and ending as shallow marine tidally dominated environments. The first sequence includes the traditional Stockdale, Breckhorn and lower Nababis formations (Zamnarib Member). The second sequence includes the upper Nababis (Haribes Member) and Gross Aub formations. As a result, the Nababis and Gross Aub formations require emendation: a new formation including the Haribes and Rosenhof and possibly also the Deurstamp members. In addition, four distinct sequence stratigraphic units are deter-minable for the Fish River Subgroup in the southern part of the basin. The Proterozoic–Cambrian transition in southern Namibia is most probably located as low as the middle Schwarzrand Subgroup. The environmentally controlled occurrence of Trichophycus pedum undermines the local stratigraphic significance of this trace fossil which is eponymous with the lowest Cambrian and Phanerozoic trace fossil assemblage on a global scale. However, occurrences of such trace fossils have to be regarded as positive evidence for Phanerozoic age regardless of co-occurring body fossils. Other suggestions strongly dispute the concept of the formal Proterozoic–Cambrian and Precambrian–Phanerozoic boundary. Carbon isotope excursions and radiometric datings for the Nama Group do not help to calibrate precisely the temporal extent of the Fish River Subgroup. Fossil content, sequence stratigraphy and inferred depositional developments suggest that this subgroup represents only a short period of late orogenic molasse sedimentation during the early sub-trilobitic Early Cambrian.

Trace fossils from the Precambrian–Cambrian boundary candidate at Meishucun, Jinning, Yunnan, China

1986 ◽  
Vol 123 (6) ◽  
pp. 641-649 ◽  
Author(s):  
T. P. Crimes ◽  
Jiang Zhiwen
Keyword(s):  
Reference Point ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Early Cambrian ◽  
Late Precambrian ◽  
Or Groups

AbstractThe Precambrian–Cambrian boundary candidate section at Meishucun, China, has yielded trace fossils which are abundant at some horizons. The earliest occur in Unit 3 of the Zhongyicun Member approximately 8 m above the lower selected stratotype reference point for the boundary and includeArenicolitessp.,Asteriacitessp.,Neonereites biserialis, N. uniserialisandSellaulichnus meishacunensis. The next trace-fossil-bearing horizon is in Unit 6 of the Zhongyicun Member whereCochlichnussp.,Monomorphichnussp.,Neonereites biserialisandN. uniserialisoccur. Immediately above, in Unit 7, areCruzianasp.,Didymaulichnus miettensis, Monomorphichnussp. andRusophycussp. In the Badaowan Member at the top of the section there areDidymaulichnussp. andTaphrhelminthopsis circularisin Unit 9,Arenicolitessp.,Diplocraterionsp.,Gordia molassica, Skolithossp. andT. circularisin Unit 11, andGordia meandria, ?Plagiogmussp.,Skolithossp. andT. circularisin Unit 12.Comparison of this trace-fossil distribution with that in key Precambrian–Cambrian boundary sections in other countries indicates that the ranges of a few trace fossils cross the boundary (e.g.Didymaulichnus, Neonereites, Planolites) but most appear only in the Cambrian. Different ichnogenera seem to appear at various levels above the boundary.ArenicolitesandAsteriacitesare among the first, whileTaphrhelminthopsis circularisis only encountered higher in all sequences. Some have only been recorded at much higher levels and relatively close to the first appearance of trilobites (e.g.Cruziana, Diplocraterion, Rusophycus). This suggests that the first appearance of specific trace fossils or groups of trace fossils may be valuable for locating the boundary in some sections and for correlating late Precambrian and early Cambrian strata.

scholarly journals Paleoecologic and Biostratigraphic Significance of Trace Fossils From Shallow- to Marginal-Marine Environments From the Middle Cambrian (Stage 5) of Jordan

2012 ◽  
Vol 86 (6) ◽  
pp. 931-955 ◽  
Author(s):  
Richard Hofmann ◽  
M. Gabriela Mángano ◽  
Olaf Elicki ◽  
Rafie Shinaq
Keyword(s):  
Trace Fossils ◽  
Trace Fossil ◽  
Type Locality ◽  
Early Cambrian ◽  
Marine Environments ◽  
Middle Cambrian ◽  
Fossil Assemblages ◽  
Maximum Flooding Surface

The Hanneh Member (Cambrian Stage 5) of the Burj Formation and the Umm Ishrin Formation of Jordan represent a transgressive-regressive succession that contains twenty-eight ichnotaxa, including vertical burrows (Arenicolitesisp.,Diplocraterionisp.,Gyrolithes polonicus,Rosseliaisp.,Skolithos linearis, escape trace fossils), horizontal simple burrows and trails (Archaeonassa fossulata,Gordia marina,Helminthoidichnites tenuis,Palaeophycus tubularis,Planolites beverleyensis,P. montanus), plug-shaped burrows (Bergaueria sucta), horizontal branched burrows (Asterosomaisp.,Phycodesisp.,Treptichnuscf.T. pedum), bilobate structures (various ichnospecies ofCruzianaandRusophycus), and trackways and scratch marks (Diplichnitesisp.,Dimorphichnuscf.D. obliquus,Monomorphichnusisp.). Eleven trace-fossil assemblages are identified. TheArenicolitesisp. andDiplocraterionisp. assemblages occur in transgressive tidal dunes and bars whereas theRosseliaisp. assemblage characterizes areas between tidal dunes. TheCruziana salomonisassemblage reflects a wide variety of environmental settings including channels within tidal-bar complexes, bottomsets of tidal dunes, and interdune areas. TheGordia marinaassemblage is present between dune patches. TheGyrolithes polonicusassemblage penetrates into firmground mudstone below the maximum flooding surface. TheBergaueria sucta,Archaeonassa fossulata,Rusophycus aegypticusandCruziana problematicaassemblages occur in different subenvironments of the progradational delta.Cruziana salomonisandRusophycus burjensis, originally considered indicative of an early Cambrian age, are actually middle Cambrian in their type locality. Occurrences ofCruziana jordanicaandRusophycus aegypticusprovide evidence that these ichnospecies are of the same age in Jordan and may co-exist in terms of stratigraphic distribution withC. salomonisandR. burjensis.

scholarly journals Coniacian sandstones from the North Sudetic Synclinorium revisited: palaeoenvironmental and palaeogeographical reconstructions based on trace fossil analysis and associated body fossils

Geologos ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 29-53 ◽  
Author(s):  
Alina Chrząstek ◽  
Monika Wypych
Keyword(s):  
Trace Fossils ◽  
Trace Fossil ◽  
Fair Weather ◽  
Soft Substrate ◽  
Southeastern Part ◽  
Shallow Marine ◽  
The North ◽  
Low Diversity ◽  
Storm Deposits ◽  
Interesting Compound

AbstractThe Coniacian quartz sandstones (Żerkowice Member, Rakowice Wielkie Formation) that crop out at quarries near Czaple-Nowa Wieś Grodziska (North Sudetic Synclinorium) contain a low-diversity assemblage of trace fossils:Gyrochorteisp.,Ophiomorpha nodosaLundgren, 1891,Ophiomorphaisp.,Phycodescf.curvipalmatum(Pollard, 1981), ?Phycodesisp.,Planolitescf.beverleyensis(Billings, 1862),Thalassinoides paradoxicusWoodward, 1830 and ?Thalassinoidesisp. Moreover, interesting compound burrow systems, here referred to asThalassinoides-Phycodescf.palmatusand ?Thalassinoides-Phycodes, were recognised at the Czaple Quarry. Additionally, ?Gyrochorteisp.,Phycodescf.flabellum(Miller and Dyer, 1878) and ?Treptichnusisp. were encountered at correlative levels in the Rakowice Małe Quarry. Some of these ichnotaxa have not been recorded previously from Coniacian sandstones of the Żerkowice Member. Additionally, in slabs of these sandstones, the gastropodNerinea bicinctaBronn, 1836 and the bivalveLima haidingeriZittel, 1866 were found. These interesting finds, in particular the gastropods, were already noted from the study area in the first half of the twentieth century by Scupin (1912–1913). Ethologically, the trace fossil assemblage is represented by domichnia or domichnia/fodinichnia (Ophiomorpha,Thalassinoides), fodinichnia (Phycodes) and pascichnia (Gyrochorte,Planolites). The compound burrow systems (Thalassinoides-Phycodes) are interpreted as dwelling/feeding structures. The possible tracemakers are crustaceans (Ophiomorpha,Thalassinoides) or worm-like animals (annelids and other) (Planolites, ?Phycodes,Gyrochorteand ?Treptichnus). The assemblage of trace fossils is characteristic of theSkolithosichnofacies andCruzianaichnofacies, typical of shallow-marine settings. Ichnological studies, as well as the presence of accompanying fossils (bivalves, gastropods), confirm the palaeoenvironmental reconstruction of the Żerkowice Member sandstones by Leszczyński (2010). That author interpreted the Coniacian sandstones as bar and storm deposits laid down in a shallow epicontinental sea (mainly the foreshore-upper shoreface; up to the middle shoreface) under normal oxygenation and salinity, in soft substrate, above fair-weather wave base. The deposition of the Żerkowice Member sandstones is linked to a regression that started after uplift of the southeastern part of the North Sudetic Synclinorium.

Stratigraphy and sedimentology of the Hamill Group in the northern Selkirk Mountains, British Columbia: evidence for latest Proterozoic – Early Cambrian extensional tectonism

1989 ◽  
Vol 26 (3) ◽  
pp. 515-533 ◽  
Author(s):  
William J. Devlin
Keyword(s):  
British Columbia ◽  
Fault Scarp ◽  
Gravity Flow ◽  
Tectonic Activity ◽  
Turbidity Currents ◽  
Early Cambrian ◽  
Shallow Marine ◽  
Sedimentary Characteristics ◽  
Sediment Gravity Flow ◽  
Selkirk Mountains

Three informal stratigraphic divisions are recognized in the uppermost Proterozoic – Lower Cambrian Hamill Group in the northern Selkirk Mountains of British Columbia. These informal divisions include a lower sandstone unit, a greenstone–graded-sandstone unit, and an upper sandstone unit. Both the lower and upper sandstone units display sedimentary characteristics that are uniform along strike and indicate a shallow-marine environment of deposition. As is typical of other exposures of the Hamil Group in southeastern British Columbia, the lower sandstone unit is coarser grained and more poorly sorted than the mature quartz arenites of the upper sandstone unit.The greenstone–graded-sandstone unit is a complex assemblage of mafic metavolcanic rocks and associated sandstone facies. This unit is highly variable along strike but essentially consists of a thick succession of subaqueous extrusive rocks overlain by a variety of sediment gravity-flow deposits. These latter deposits include resedimented conglomerates, debris-flow deposits, and trubidites (deposited from both high- and low-density turbidity currents). Stratigraphic sections of this unit are described in detail from three different localities and are examined in terms of their transport and depositional mechanisms.The stratigraphic succession of the Hamill Group indicates that deposition of the shallow-marine sands of the lower sandstone unit was abruptly interrupted by a period of volcanism, the creation of a paleoslope, and the deposition of a large volume of sediment gravity-flow deposits of the greenstone–graded-sandstone unit. These relations are attributed to an episode of syndepositional normal faulting. The inferred fault(s) could have served as the conduit for the extrusion of the volcanics. Offset along the fault(s), the tilting of fault blocks, and the consequent formation of an unstable slope adjacent to a fault scarp created an environment favorable for deposition of the sediment gravity flows. In general, deposition of proximal, base-of-slope deposits was followed by an aggradational basin-fill phase of sedimentation. With the waning of tectonic activity and the filling of the fault-bounded basin, depositon of shallow-marine sands resumed (the upper sandstone unit). The stratigraphic relations of the Hamill Group in the northern Selkirk Mountains are considered direct evidence for an episode of latest Proterozoic – Early Cambrian extensional tectonism. The evidence for an episode of rift-related tectonism in the northern Selkirk Mountains supports inferences concerning the timing of this event as derived from tectonic subsidence analyses of post-rift strata of the Cordilleran miogeocline.

THE BASAL SEDIMENTARY ROCKS IN SOMERSET ISLAND, N.W.T.

1966 ◽  
Vol 3 (5) ◽  
pp. 697-711 ◽  
Author(s):  
M. F. Tuke ◽  
D. L. Dineley ◽  
B. R. Rust
Keyword(s):  
Marine Environment ◽  
Coastal Lagoons ◽  
Sedimentary Rocks ◽  
Trace Fossils ◽  
Middle Cambrian ◽  
Shallow Marine ◽  
Sedimentary Structures ◽  
Basement Rocks ◽  
Metamorphic Basement ◽  
Somerset Island

In northwest Somerset Island quartz sandstones of the Aston formation and dolostones of the overlying Hunting formation rest unconformably on metamorphic basement rocks. Except for stromatolites and trace fossils the formations are unfossiliferous, and their age has been interpreted as Proterozoic by previous authors.The Aston sandstones pass conformably upward into the Hunting dolostones, which are conformably overlain by Ordovician strata. A similar succession with Middle Cambrian trilobites at the base occurs on Boothia Peninsula. It is therefore suggested that the Aston and Hunting formations comprise a Palaeozoic succession continuous with the fossiliferous Ordovician rocks. This hypothesis does not appear to be incompatible with regional interpretations of Proterozoic–Palaeozoic relationships.The sedimentary structures and petrology of the Aston sandstones suggest that they were derived from the basement rocks and deposited in a shallow marine environment. Sedimentary structures and stromatolites in the Hunting dolostones show that they were laid down in coastal lagoons and tidal flats.

Trace fossil assemblages reflecting stressed environments in the Middle Jurassic Carmel Seaway of central Utah

1999 ◽  
Vol 73 (4) ◽  
pp. 711-720 ◽  
Author(s):  
J. M. De Gibert ◽  
A. A. Ekdale
Keyword(s):  
Benthic Community ◽  
Middle Jurassic ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Pore Waters ◽  
Shallow Marine ◽  
Marine Carbonate ◽  
Marine Carbonates ◽  
Low Diversity ◽  
Fossil Assemblages

The shallow-marine Carmel Formation (Middle Jurassic) in central Utah hosts low-diversity trace fossil assemblages, including Arenicolites, Chondrites, Gyrochorte, Lockeia, Planolites, Protovirgularia, Rosselia, Scalarituba, Skolithos, Taenidium, and Teichichnus. Non specialized ichnotaxa with a remarkably small burrow size dominate the assemblages. The amount of bioturbation is lower than expected in comparison with modern shallow-marine carbonate environments. These ichnological features also are significantly different from those of other Jurassic shallow-marine carbonates. The trace fossils represent an environmentally stressed benthic community in a marginal marine, restricted setting, with salinities above normal marine and with depletion of oxygen in pore waters.

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