Saga de deux bassins : juxtaposition du bassin fossilifère édiacarien de St. John’s contre le bassin glaciovolcanique de Bonavista sur la péninsule de Bonavista, zone d’Avalon, Terre-Neuve
DOI :
https://doi.org/10.4138/atlgeo.2024.007Résumé
Le supergroupe de Musgravetown (SGM) du bassin de Bonavista constitue l’unité centrale de strates néoprotérozoïques sur la péninsule de Bonavista, dans la zone d’Avalon, dans le nord-est de Terre-Neuve. Dans l’ouest de Bonavista, le groupe marin profond d’environ 620 à 600 Ma, Connecting Point (GCP), est recouvert de façon discordante par le SGM volcanosédimentaire terrestre à marin peu profond d’environ 600 à 540 Ma, mais il est limité par des failles à l’est de la faille Indian Arm. Dans l’est de la péninsule de Bonavista, la faille de l’anse Spillars sépare le SGM des roches du bassin de St. John’s, corrélatives des strates édiacariennes de la presqu’île Avalon (groupes de Conception, St. John’s et Signal Hill) comme le corrobore une datation U–Pb d’environ 566 Ma. Les limites d’âge citées aux présentes confirment l’importance régionale de la faille de l’anse Spillars qui limite temporellement et stratigraphiquement les strates distinctes.
Les roches magmatiques du groupe Bull Arm (SGM basal) se sont mises en place durant une extension régionale prolongée. Le début de l’épisode est marqué par l’éruption de basalte calcoalcalin il y a environ 600 Ma et le dépôt contemporain de conglomérat de galets sur la discordance d’environ 605 à 600 Ma du GCP-SGM dans l’ouest de la péninsule de Bonavista. L’extension s’est poursuivie par l’extrusion de tufs et de roches volcaniques bimodales d’environ 592 Ma de la ceinture volcanique de l’anse Plate à l’est de la faille Indian Arm. La ceinture est recouverte à l’est par le groupe principalement clastique de Rocky Harbour. Ses tufs et sa pépérite, datées par endroits à environ 585 et 576 Ma, respectivement, encadrent la diamictite d’environ 580 Ma de Trinity — un équivalent marin peu profond de la Formation marine profonde Gaskiers du bassin de St. John’s sur la presqu’île Avalon. Les basaltes alcalins de faible volume au-dessous et au-dessus de la diamictite de Trinity établissent un lien spatio-temporel clair entre la glaciation et le magmatisme d’extension. Les strates au-dessous de la diamictite de Trinity affichent des caractéristiques témoignant d’une origine glaciogène et accroissent l’épaisseur et l’étendue aréale des dépôts glaciaires édiacariens de Gaskiers. La glaciation de Gaskiers a vraisemblablement duré plusieurs millions d’années et a été concomitante au magmatisme d’extension d’environ 600 à 576 Ma à l’intérieur de la zone occidentale de proto-Avalonia ou le long de sa marge.
Références
Álvaro, J.J. and Mills, A. 2024. Carbonate production and reef building under ferruginous seawater conditions in the Cambrian rift branches of the Avalon Zone, Newfoundland. Sedimentology, 71, pp. 1245–1269. https://doi.org/10.1111/sed.13172
Anderson, M.M. and King, A.F. 1981. A possible time span for the late Precambrian of the Avalon Peninsula, southeast Newfoundland, in light of fossils, tillites and rock succession. Canadian Journal of Earth Sciences, 9, pp. 1710–1726. https://doi.org/10.1139/e72-151
Anderson, M.A. and Misra, S.B. 1968. Fossils found in the Precambrian Conception Group in southeastern Newfoundland. Nature, 220, pp. 680–681. https://doi.org/10.1038/220680a0
Benus, A. P. 1988. Sedimentological context of a deep-water Ediacaran fauna (Mistaken Point, Avalon Zone, eastern Newfoundland). Abstract In Trace Fossils, Small Shelly Fossils and the Precambrian – Cambrian Boundary, The University of the State of New York, Bulletin 463, pp. 8–9.
Beranek, L.P., Hutter, A.D., Pearcey, S., James, C., Langor, V., Pike, C., Goudie, D., and Oldham, L. 2023. New evidence for the Baltican cratonic affinity and Tonian to Ediacaran tectonic evolution of West Avalonia in the Avalon Peninsula, Newfoundland, Canada. Precambrian Research, 390. https://doi.org/10.1016/j.precamres.2023.107046
Brückner, W.D. and Anderson, M.A. 1971. Late Precambrian glacial deposits in southeastern Newfoundland – a preliminary note. Proceedings from the Geological Association of Canada, 24, pp. 449–479.
Calon, T. 2001. Late Precambrian sedimentation and related orogenesis of the Avalon Peninsula, eastern Avalon Zone, Newfoundland. Geological Association of Canada, St. John’s 2001 Field Trip Guidebook, A9/B8, pages 1–32.
Canfield, D.E., Knoll, A.H., Poulton, S.W., Narbonne, G.M., Dunning, G.R. 2020. Carbon isotopes in clastic rocks and the Neoproterozoic carbon cycle. American Journal of Science, 320, pp. 97–124. https://doi.org/10.2475/02.2020.01
Carto, S.L. and Eyles, N. 2012. Identifying glacial influences on sedimentation in tectonically active, mass flow dominated arc basins with reference to the Neoproterozoic Gaskiers glaciation (c. 580 Ma) of the Avalon–Cadomian Orogenic Belt. Sedimentary Geology, 261–262, pp. 1–14. https://doi.org/10.1016/j.sedgeo.2012.02.006
Cocks, L.R.M. and Fortey, R.A. 2009. Avalonia: a long-lived terrane in the Lower Palaeozoic? Geological Society, London, Special Publications, 325, pp. 141–155. https://doi.org/10.1144/SP325.7
Colman-Sadd, S.P., Hayes, J.P., and Knight, I.1990. Geology of the Island of Newfoundland (digital version of Map 90-01). Government of Newfoundland and Labrador, Department of Mines and Energy, Geological Survey Branch. Open File NFLD/2192, scale: 1:1 000 000.
Dec, T., O’Brien, S.J. and Knight, I. 1992. Late Precambrian volcaniclastic deposits of the Avalonian Eastport basin (Newfoundland Appalachians): petrofacies, detrital clinopyroxene and paleotectonic implications. Precambrian Research, 59, pp. 243–262. https://doi.org/10.1016/0301-9268(92)90059-W
Fitzgerald, D.M., Narbonne, G.M., Pufahl, P.K., and Dalrymple, R.W. 2024. The Mall Bay Formation (Ediacaran) and the protracted onset of the Gaskiers glaciation in Newfoundland, Canada. Precambrian Research, 405. 1062. https://doi.org/10.1016/j.precamres.2024.107369
Folk, R.L. 1980. Petrology of Sedimentary Rocks. Austin. Hemphill Publishing Co., USA, 182 p.
Gardiner, S. and Hiscott, R.N. 1988. Deep-water facies and depositional setting of the lower Conception Group (Hadrynian), southern Avalon Peninsula, Newfoundland. Canadian Journal of Earth Sciences, 25, pp. 1579–1594. https://doi.org/10.1139/e88-151
Gehling, J.G. and Narbonne, G.M. 2007. Spindle-shaped Ediacara fossils from the Mistaken Point assemblage, Avalon Zone, Newfoundland. Canadian Journal of Earth Sciences, 44, pp. 367–387. https://doi.org/10.1139/e07-003
Gehling, J.G., Narbonne, G.M., and Anderson, M.M. 2000. The first named Ediacaran body fossil, Aspidella Terranovica. Palaeontology, 43 (3), pp. 427–456. https://doi.org/10.1111/j.0031-0239.2000.00134.x
Gómez, N., Lowe, D., Mills, A., Slaney, N., and Arnott, R.W.C. 2024. Ediacaran proximal glaciomarine sedimentation in the Bonavista Peninsula, Avalon Zone (Newfoundland). European Geological Union General Assembly 2024, poster presentation. https://doi.org/10.5194/egusphere-egu24-6919
Gravenor, C.P. 1980. Heavy minerals and sedimentological studies on the glaciogenic Late Precambrian Gaskiers Formation of Newfoundland. Canadian Journal of Earth Sciences, 17, pp. 1331–1341. https://doi.org/10.1139/e80-140
Hinchey, J.G. 2010. Neoproterozoic sediment-hosted ‘stratiform’ copper mineralization – Bonavista Peninsula, Avalon Zone, Newfoundland: initial field and petrographic observations. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 10-1, pp. 1–21.
Hinchey, J. 2012. Preliminary insights into lithogeochemical signatures and possible provenance of reduced sedimentary units associated with copper mineralization–western Avalon Zone, Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 12-1, pp. 1–20.
Hofmann, H.J., O’Brien, S.J., and King, A.F. 2008. Ediacaran biota on Bonavista Peninsula, Newfoundland, Canada. Journal of Paleontology, 82, pp. 1–36. https://doi.org/10.1666/06-087.1
Israel, S. 1998. Geochronological, structural and stratigraphic investigation of a Precambrian unconformity between the Harbour Main Group and Conception Group, east coast Holyrood Bay, Avalon Peninsula, Newfoundland, unpublished B.Sc. (Honours) thesis, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, 78 p.
Jenness, S.E. 1963. Terra Nova and Bonavista map-areas, Newfoundland (2D E1/2 and 2C). Geological Survey of Canada, Memoir 327, 184 p. https://doi.org/10.4095/123899
King, A.F. 1988. Geology of the Avalon Peninsula, Newfoundland (parts of 1K, 1L, 1M, 1N and 2C). Newfoundland Department of Mines and Energy, Map 88-01, scale 1:250 000.
King, A.F. 1990. Geology of the St. John’s area. Report 90-2. Geological Survey Branch, Department of Mines and Energy, Government of Newfoundland and Labrador. Report 90-2. 93 p.
Krogh, T.E. 1973. A low-contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determinations. Geochimica et Cosmochimica Acta, 33 (3), pp. 485–494. https://doi.org/10.1016/0016-7037(73)90213-5
Krogh, T.E., Strong, D.F., O’Brien, S.J., and Papezik, V.S. 1988. Precise U–Pb zircon dates from the Avalon Terrane in Newfoundland, Canadian Journal of Earth Sciences, 25, pp. 442–453. https://doi.org/10.1139/e88-045
Lamoso, I.S.M., Babinski, M., Caetano-Filho, S., Paula-Santos, G.M., and Hollanda, M.H.B.M. 2023. A record of the Snowball Earth Events? The Parecis Basin may encompass three major Neoproterozoic Glaciations on the Amazonian Craton. Journal of South American Earth Sciences, 127. 104411. https://doi.org/10.1016/j.jsames.2023.104411
Landing, E. 1996. Avalon: Insular continent by the latest Precambrian, In Avalonian and Related Peri-Gondwanan Terranes of the Circum-North Atlantic. Edited by R.D. Nance and M.D. Thompson, M.D. Geological Society of America Special Paper 304, pp. 27–64. https://doi.org/10.1130/0-8137-2304-3.29
Liu, A.G., Matthews, J.J., Menon, L.R., McIlroy, D., and Brasier, M.D. 2014. Haootia quadriformis n. gen., n. sp., interpreted as a muscular cnidarian impression from the Late Ediacaran period (approx. 560 Ma). Proceedings of the Royal Society, 281. 20141202 http://dx.doi.org/10.1098/rspb.2014.1202
Liu, A.G., Kenchington, C.G., and Mitchell, E.G. 2015. Remarkable insights into the paleoecology of the Avalonian Ediacaran macrobiota. Gondwana Research, 27, pp. 1355–1380. https://doi.org/10.1016/j.gr.2014.11.002
Liu, A.G., Matthews, J.J., and McIlroy, D. 2016. The Beothukis/Culmofrons problem and its bearing on Ediacaran macrofossil taxonomy: evidence from an exceptional new fossil locality. Palaeontology, 59, Part 1, pp. 45–58. https://doi.org/10.1111/pala.12206
Lowe, D.G. and Arnott, R.W.C. 2016. Stratal composition and architecture of braided and sheetflood-dominated ephemeral fluvial strata in the Cambrian–Ordovician Potsdam Group: A case example of the response of pre-vegetation fluvial systems and climate change. Journal of Sedimentary Research, 86, pp. 587–612. https://doi.org/10.2110/jsr.2016.39
Lowe, D., Serna-Ortiz, S., Khatrine, G., and Bryce, J. 2024. The inception, evolution, and terrane-scale significance of a Late Ediacaran foreland basin in the eastern Avalon Zone of Newfoundland, Canada. Atlantic Geoscience Society, 50th Colloquium and Annual Meeting. Atlantic Geoscience, 60, 98 p.
Maclennan, J., Jull, M., McKenzie, D., Slater, L., and Grönvold, K. 2002. The link between volcanism and deglaciation in Iceland. Geochemistry Geophysics Geosystems, 3 (11). https://doi.org/10.1029/2001GC000282
Mason, S.J., Narbonne, G.M., Dalrymple, R.W., and O’Brien, S.J. 2013. Paleoenvironmental analysis of Ediacaran strata in the Catalina Dome, Bonavista Peninsula, Newfoundland. Canadian Journal of Earth Sciences, 50, pp. 197–212. https://doi.org/10.1139/cjes-2012-0099
Mattinson, J.M. 2005. Zircon U–Pb chemical abrasion (“CA-TIMS”) method: Combined annealing and multi-step partial dissolution analysis for improved precision and accuracy of zircon ages. Chemical Geology, 220 (1–2), pp. 47–66. https://doi.org/10.1016/j.chemgeo.2005.03.011
Matthews, J.J., Liu, A.G., Yang, C., McIlroy, D., Levell, B. and Condon, D.J. 2020. A chronostratigraphic framework for the rise of the Ediacaran macrobiota: New constraints from Mistaken Point Ecological Reserve, Newfoundland. Geological Society of America, Bulletin 133 (3–4), pp. 612–624. https://doi.org/10.1130/B35646.1
McIlroy, D., Crimes, T.P., and Pauley, J.C. 2005. Fossils and matgrounds from the Neoproterozoic Longmyndian Supergroup, Shropshire, UK. Geological Magazine, 142 (4), pp. 441–455. https://doi.org/10.1017/S0016756805000555
Mills, A.J. and Lowe, D. 2022. Geology of the Bonavista Peninsula, Newfoundland: a trail of discovery through the Ediacaran Musgravetown Group of Avalonia. GAC/MAC Halifax 2022 virtual field trip guidebook, 33 p.
Mills, A.J. and Sandeman, H.A.I. 2015. Preliminary lithogeochemistry for mafic volcanic rocks from the Bonavista Peninsula, northeastern Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 15-1, pp. 173–189.
Mills, A. and Sandeman, H. 2021. Lithostratigraphy and lithogeochemistry of Ediacaran basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin the type-Avalon terrane. Atlantic Geology, 57, pp. 207–234. https://doi.org/10.4138/atlgeol.2021.010
Mills, A.J., Calon, T., and Peddle, C. 2016a. Preliminary investigations into the structural geology of the Bonavista Peninsula, northeast Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 16-1, pp. 133–152.
Mills, A.J., Dunning, G.R., and Langille, A. 2016b. New geochronological constraints on the Connecting Point Group, Bonavista Peninsula, Avalon Zone, Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 16-1, pp. 153–171.
Mills, A.J., Dunning, G.R., Murphy, M., and Langille, A. 2017. New geochronological constraints on the timing of magmatism for the Bull Arm Formation, Musgravetown Group, Avalon Terrane, Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 17-1, pp. 1–17.
Mills, A.J., Dunning, G., and Sandeman, H. 2021. Age-constrained arc- to rift-magmatism in northwestern and central Avalon Terrane, Newfoundland, and implications for lithostratigraphy, Canadian Journal of Earth Sciences, 58, pp. 332–354. https://doi.org/10.1139/cjes-2019-0196
Misra, S.B. 1969. Late Precambrian (?) fossils from southeastern Newfoundland. Geological Society of America Bulletin, 463, pp. 841–845. https://doi.org/10.1130/0016-7606(1969)80[2133:LPFFSN]2.0.CO;2
Narbonne, G.M. and Gehling, J.G. 2003. Life after snowball: The oldest complex Ediacaran fossils. Geology, 31, pp. 27–30. https://doi.org/10.1130/0091-7613(2003)031<0027:LASTOC>2.0.CO;2
Normore, L.S. 2010. Geology of the Bonavista map area (NTS 2C/11), Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 10-1, pp. 281–301.
Normore, L.S. 2011. Preliminary findings on the geology of the Trinity map area (NTS 2C/06), Newfoundland. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 11-1, pp. 273–293.
O’Brien, S.J. and King, A.F. 2002. Neoproterozoic stratigraphy of the Bonavista Peninsula: preliminary results, regional correlations and implications for sediment-hosted stratiform copper exploration in the Newfoundland Avalon Zone, In Current Research, Newfoundland Department of Mines and Energy Geological Survey, Report 02-1, pp. 229–244.
O’Brien, S.J. and King, A.F. 2004a. Ediacaran fossils from the Bonavista Peninsula (Avalon Zone), Newfoundland: preliminary descriptions and implications for regional correlation. In Current Research, Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 04-1, pp. 203–212.
O’Brien, S.J. and King, A.F. 2004b. Late Neoproterozoic to earliest Paleozoic stratigraphy of the Avalon Zone in the Bonavista Peninsula, Newfoundland: an update, In Current Research, Newfoundland Department of Mines and Energy Geological Survey, Report 04-1, pp. 213–224.
O’Brien, S.J. and King, A.F. 2005. Late Neoproterozoic (Ediacaran) stratigraphy of the Avalon Zone sedimentary rocks, Bonavista Peninsula, Newfoundland. In Current Research. Newfoundland and Labrador Department of Natural Resources, Geological Survey, Report 05-1, pp. 101–114.
O’Brien, S.J., O’Brien, B.H., Dunning, G.R. and Tucker, R.D. 1996. Late Neoproterozoic Avalonian and related peri-Gondwanan rocks of the Newfoundland Appalachians. In Avalonian and Related Peri-Gondwanan Terranes of the Circum-North Atlantic. Edited by R.D. Nance, and M.D. Thompson, M.D. Geological Society of America Special Paper 304, pp. 9–28. https://doi.org/10.1130/0-8137-2304-3.9
O’Brien, S.J., Dunning, G.R., Dubé, C.F, Sparkes, B., Israel, S. and Ketchum, J. 2001. New insights into the Neoproterozoic geology of the central Avalon Peninsula (parts of NTS map areas 1N/6, 1N/7 and 1N/3), Eastern Newfoundland, In Current Research, Newfoundland Department of Mines and Energy Geological Survey, Report 2001-1, pp. 169–189.
Passchier, S. and Erukanure, E. 2010. Palaeoenvironments and weathering regime of the Neoproterozoic Squantum ‘Tillite’, Boston Basin: no evidence of a snowball Earth. Sedimentology, 57, pp. 1526–1544. https://doi.org/10.1111/j.1365-3091.2010.01154.x
Pollock, J.C., Hibbard, J.P., and Sylvester, P.J. 2009. Early Ordovician rifting of Avalonia and birth of the Rheic Ocean: U–Pb detrital zircon consrtraints from Newfoundland. Journal of the Geological Society, London, 166, pp. 501–515. https://doi.org/10.1144/0016-76492008-088
Pu, J.P., Bowring, S.A., Ramezani, J., Myrow, P., Raub, T.D., Landing, E., Mills, A., Hodgin, E., and Macdonald, F.A. 2016. Dodging snowballs: Geochronology of the Gaskiers glaciation and the first appearance of the Ediacaran biota. Geology, Geological Society of America, Data Repository item 2016326;, 4 pp. https://doi.org/10.1130/G38284.1
Rice, A.H.N., Edwards, M.B., Hansen, T.A., Arnaud, E., and Halverson, G.P. 2011. Chapter 57: Galciogenic rocks of the Neoproterozoic Smalfjord and Mortensnes formations, Vestertana Group, E. Finnmark, Norway. Geological Society, London, Memoirs, 36, pp. 593–602. https://doi.org/10.1144/M36.57
Serna Ortiz, S. and Lowe, D.G. 2024. Stratal evolution and provnenance of a Precambrian delta in a tectonically active terrane: The lower Signal Fill Group, Avalon Zone, Newfoundland. Precambrian Research, 401, 107274. https://doi.org/10.1016/j.precamres.2023.107274
Sparkes, G.W. 2005. The geological setting, geochemistry and geochronology of host rocks to high- and low-sulphidation style epithermal systems of the eastern Avalon High-Alumina Belt, eastern Avalon Zone, Newfoundland. Unpublished M.Sc. thesis, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, 313 pp.
Sparkes, G.W. and Dunning, G.R. 2014. Late Neoproterozoic epithermal alteration and mineralization in the western Avalon Zone: a summary of mineralogical investigations and new U/Pb geochronological results. In Current Research, Newfoundland Department of Natural Resources, Geological Survey, Report 14-1, pp. 99–128.
Stacey, J.S. and Kramers, J.D. 1975. Approximation of terrestrial lead isotope evolution by a two stage model. Earth and Planetary Science Letters, 26, pp. 207–221. https://doi.org/10.1016/0012-821X(75)90088-6
Thompson, M.D., Ramezani, J., and Crowley, J.L. 2014. U–Pb zircon geochronology of Roxbury conglomerate, Boston Basin, Massachusetts: tectonostratigraphic implications for Avalonia in and beyond SE New England. American Journal of Science, 314, pp. 1009–1040. https://doi.org/10.2475/06.2014.02
van Staal, C.R. and Barr, S.M. 2012. Lithospheric architecture and tectonic evolution of the Canadian Appalachians and associated Atlantic margin. In Chapter 2: Tectonic Styles in Canada: the LITHOPROBE Perspective. Edited by J.A. Percival, F.A. Cook, and R.M. Clowes. Geological Association of Canada, Special Paper 49, pp. 41–95.
van Staal, C.R., Barr, S.M., McCausland, P.J.A., Thompson, M.D., White, C.E. 2020. Tonian–Ediacaran tectonomagmatic evolution of West Avalonia and its Ediacaran–Early Cambrian interactions with Ganderia: an example of complex terrane transfer due to arc-arc collision? Geolgical Society, London, Special Publications, 503, pp. 143–168. https://doi.org/10.1144/SP503-2020-23.
Wang, R., Yin, Z., and Shen, B. 2023a. A late Ediacaran ice age: The key node in the Earth system evolution. Earth-Science Revews ,247. 104610. https://doi.org/10.1016/j.earscirev.2023.104610
Wang, R., Shen, B., Lang, X., Wen, B., Mitchell, R.N., Ma, H., Yin, Z., Peng, Y., Liu, Y., and Zhou, C. 2023b. A Great late Ediacaran ice age. National Science Review, 10. Nwad117. httsp://doi.org/10.1093/nsr/nwad117
Widmer, K. 1949. Unpublished map and incomplete report on the Glovertown – Clode Sound area. Geological Survey of Newfoundland. [2D9/65]
Williams, H. and King. A.F. 1979. Trepassey map area, Newfoundland. Geological Survey of Canada, Memoir 389, 24 pp. https://doi.org/10.4095/124055
Wilson, A.M. and Russell, J.K. 2020. Glacial pumping of a magma-charged lithosphere: A model for glaciovolcanic causality in magmatic arcs. Earth and Planetary Science Letters, 548. 116500. https://doi.org/10.1016/j.epsl.2020.116500
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