Ediacaran fossils and dubiofossils, Miette Group of Mount Fitzwilliam area, British Columbia

1991 ◽  
Vol 28 (10) ◽  
pp. 1541-1552 ◽  
Author(s):  
H. J. Hofmann ◽  
E. W. Mountjoy ◽  
M. W. Teitz
Keyword(s):  
British Columbia ◽  
Shallow Water ◽  
Rocky Mountains ◽  
Carbonate Mounds ◽  
Windermere Supergroup

Shallow-water clastic beds flanking stromatolitic carbonate mounds in the upper part of the Vendian Miette Group (Windermere Supergroup) of the Rocky Mountains contain a poorly preserved, soft-bodied fauna that comprises morphologically very variable discoid remains; these include the taxa Beltanella sp., cf. B. grandis, Charniodiscus? sp., Irridinitus? sp., Nimbia occlusa, Protodipleurosoma sp., cf. P. rugulosum, and Zolotytsia? sp. and seven types of dubiofossils.

Superimposed low-grade metamorphism in the Mount Fisher area, southeastern British Columbia—implications for the East Kootenay orogeny

1982 ◽  
Vol 19 (3) ◽  
pp. 476-489 ◽  
Author(s):  
M. E. McMechan ◽  
R. A. Price
Keyword(s):  
British Columbia ◽  
Late Cretaceous ◽  
Rocky Mountains ◽  
Regional Metamorphism ◽  
Low Grade ◽  
Canadian Cordillera ◽  
Windermere Supergroup ◽  
Granitic Intrusion ◽  
Block Faulting ◽  
Middle Proterozoic

Middle Proterozoic (~1500–1350 Ma) Belt–Purcell strata exposed in the Purcell and southwestern Rocky Mountains were affected by at least three distinct episodes of deformation and regional metamorphism. The oldest episode (1300–1350 Ma) apparently terminated Belt–Purcell sedimentation and involved folding, regional metamorphism, and granitic intrusion. The second episode (800–900 Ma) occurred during deposition of the Windermere Supergroup and involved uplift, block faulting, and low-grade regional metamorphism. Mesozoic–Cenozoic metamorphism, deformation, and plutonism overprinted the results of the earlier deformation and metamorphism.Illite crystallinity and muscovite polymorph ratios indicate that Purcell strata in the Mount Fisher area are in the lower green-schist to prehnite–pumpellyite facies of regional metamorphism. In the Steeples and Fisher blocks this metamorphism is related to structures that formed during the Late Cretaceous – Paleocene deformation. However, in the Sand Creek block the regional metamorphism is related to the development of a spaced cleavage that is folded by a Late Cretaceous – Paleocene nappe. Regional considerations suggest that this cleavage formed during the 1300–1350 Ma episode of deformation and metamorphism.The "East Kootenay orogeny" as currently defined embraces the two older episodes of tectonism. It is proposed that the term East Kootenay orogeny be restricted to designate the 1300–1350 Ma episode and that the term "Goat River orogeny" designate the 800–900 Ma episode of tectonism. The East Kootenay and Goat River orogenies appear to be correlative with the Racklan and Hayhook orogenies recognized in the northern Canadian Cordillera.

Ediacaran body and trace fossils in Miette Group (Windermere Supergroup) near Salient Mountain, British Columbia, CanadaRevision of the paper was carried out by Dr. Guy Narbonne following the passing away of both Hans Hofmann (†deceased May 19, 2010) and Eric Mountjoy (†deceased June 18, 2010) after manuscript submission.

2010 ◽  
Vol 47 (10) ◽  
pp. 1305-1325 ◽  
Author(s):  
Hans J. Hofmann ◽  
Eric W. Mountjoy
Keyword(s):  
British Columbia ◽  
Shallow Water ◽  
Trace Fossils ◽  
Manuscript Submission ◽  
Windermere Supergroup ◽  
Platform Carbonates

Siliciclastic beds in the upper part of the Miette Group in southeastern British Columbia have yielded an assemblage of late Ediacaran soft-bodied macrofossils and trace fossils. The macrofossils comprise Aspidella , Bradgatia ?, and Miettia salientensis gen. et sp. nov. The ichnofossils include Archaeonassa , Cochlichnus , Didymaulichnus ?, Gordia , Halopoa , Helminthoidichnites , Helminthopsis , Planolites , and a large, unnamed crawling trace. In addition, two types of unidentified problematica are recorded, representing either tubular Vendotaenia -like body fossils, or trace fossils. The Bradgatia? constitutes the youngest occurrence of this type of fossil, and is the first to be recorded from Laurentia, having previously been noted only in Avalonia. With Cloudina and Namacalathus in associated shallow-water platform carbonates, the Miette biota in the study area contains a combination of Namibian-type and Avalonian-type elements.

New Lower Jurassic ammonite faunas from the Fernie Formation, southern Canadian Rocky Mountains

1987 ◽  
Vol 24 (8) ◽  
pp. 1688-1704 ◽  
Author(s):  
Russell L. Hall
Keyword(s):  
British Columbia ◽  
North American ◽  
Rocky Mountains ◽  
Red Deer ◽  
First Record ◽  
Lower Jurassic ◽  
Canadian Rocky Mountains ◽  
Poker Chip

New ammonite faunas are described from sections along Bighorn and Scalp creeks in central-western Alberta where Lower Jurassic parts of the Fernie Formation are exposed. The first record of the upper Sinemurian Obtusum Zone from the Fernie is based on the occurrence of Asteroceras cf. stellare and Epophioceras cf. breoni in the basal pebbly coquina on Bighorn Creek. The overlying Red Deer Member has yielded Amaltheus cf. stokesi, representing the upper Pliensbachian Margaritatus Zone; in immediately superjacent strata the first North American examples of ?Amauroceras occur together with Protogrammoceras and ?Aveyroniceras. In the basal parts of the overlying Poker Chip Shale a fauna including Harpoceras cf. falciferum, Harpoceratoides, Polyplectus cf. subplanatus, Hildaites cf. serpentiniformis, and Dactylioceras cf. athleticum is correlated with the lower Toarcian Falciferum Zone.The upper parts of the Poker Chip Shale on Fording River in southeastern British Columbia contain a fauna representing some part of the upper Toarcian, but owing to poor preservation, generic identifications are only tentatively made.

The initiation of the early Paleozoic Cordilleran miogeocline: evidence from the uppermost Proterozoic – Lower Cambrian Hamill Group of southeastern British Columbia

1988 ◽  
Vol 25 (1) ◽  
pp. 1-19 ◽  
Author(s):  
William J. Devlin ◽  
Gerard C. Bond
Keyword(s):  
British Columbia ◽  
Lower Cambrian ◽  
Direct Evidence ◽  
Thermal Anomaly ◽  
Passive Margin ◽  
Early Paleozoic ◽  
Upper Proterozoic ◽  
Windermere Supergroup ◽  
Depositional Setting ◽  
Thermal Subsidence

The uppermost Proterozoic–Lower Cambrian Hamill Group of southeastern British Columbia contains geologic evidence for a phase of extensional tectonism that led directly to the onset of thermally controlled subsidence in the Cordilleran miogeocline. Moreover, the Hamill Group contains the sedimentological record of the passage of the ancient passive margin from unstable tectonic conditions associated with rifting and (or) the earliest phases of thermal subsidence to post-rift conditions characterized by stabilization of the margin and dissipation of the thermal anomaly generated during the rift phase (the rift to post-rift transition). Widespread uplift that occurred prior to and during the deposition of the lower Hamill Group is indicated by an unconformable relation with the underlying Windermere Supergroup and by stratigraphic relations between Middle and Upper Proterozoic strata and unconformably overlying upper Lower Cambrian quartz arenites (upper Hamill Group) in the southern borderlands of the Hamill basin. In addition, the coarse grain size, the feldspar content, the depositional setting, and the inferred provenance of the lower Hamill Group are all indicative of the activation of basement sources along the margins of the Hamill basin. Geologic relations within the Hamill Group that provide direct evidence for extensional tectonism include the occurrence of thick sequences of mafic metavolcanics and rapid vertical facies changes that are suggestive of syndepositional tectonism.Evidence of extensional tectonism in the Hamill Group directly supports inferences derived from tectonic subsidence analyses that indicate the rift phase that immediately preceded early Paleozoic post-rift cooling could not have occurred more than 10–20 Ma prior to 575 ± 25 Ma. These data, together with recently reported isotopic data that suggest deposition of the Windermere Supergroup began ~730–770 Ma, indicate that the rift-like deposits of the Windermere Supergroup are too old to represent the rifting that led directly to the deposition of the Cambro-Ordovician post-rift strata. Instead, Windermere sedimentation was apparently initiated by an earlier rift event, probably of regional extent, that was part of a protracted, episodic rift history that culminated with continental breakup in the latest Proterozoic – Early Cambrian.

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