Vol. 49 No. 1 (2022)
GAC–MAC Field Guide Summary

Volcanism of the Late Silurian Eastport Formation of the Coastal Volcanic Belt, Passamaquoddy Bay, New Brunswick: GAC–MAC Halifax 2022 Pre-Meeting Field Trip

Nancy Van Wagoner
Thompson Rivers University, Department of Physical Sciences Kamloops, British Columbia, V2C 0C8
Les Fyffe
New Brunswick Geological Surveys Branch (retired), Fredericton, New Brunswick, E3B 5H1
David Lentz
Department of Earth Sciences, University of New Brunswick Fredericton, New Brunswick, E3B 5A3
Kelsie Dadd
School of Geosciences, University of Sydney, Sydney, 2006
Wayne McNeil
25 Alderney, Dartmouth, Nova Scotia, B2Y 0E4
Diane Baldwin
Minex Services, 17 Gitzel Street, Yellowknife, Northwest Territories, X1A 2C1
Geoscience Canada V.49#1 Front Page (photo and teasers).

Published 2022-03-26

Keywords

  • Bimodal volcanism,
  • Coastal Volcanic Belt,
  • Late Silurian,
  • New Brunswick

How to Cite

Van Wagoner, N., Fyffe, L., Lentz, D., Dadd, K., McNeil, W., & Baldwin, D. (2022). Volcanism of the Late Silurian Eastport Formation of the Coastal Volcanic Belt, Passamaquoddy Bay, New Brunswick: GAC–MAC Halifax 2022 Pre-Meeting Field Trip. Geoscience Canada, 49(1), 45–52. https://doi.org/10.12789/geocanj.2022.49.186

Abstract

This field trip is an excursion through the exquisite, nearly pristine exposures of a Silurian, felsic-dominated bimodal volcanic and sedimentary sequence exposed in the Passamaquoddy Bay area of southwestern, New Brunswick (Eastport Formation). These rocks form the northwest extension of the Coastal Volcanic Belt that extends from southwestern New Brunswick to the southern coast of Maine. The sequence is significant because it is part of a large bimodal igneous province with evidence for supervolcano-scale eruptions that began to form during the close of the Salinic Orogeny (about 424 Ma), and continued into the Acadian Orogeny (421–400 Ma). The geochemical characteristic of the rocks can be explained by extension related volcanism but the specific drivers of the extension are uncertain. The Passamaquoddy Bay sequence is 4 km thick and comprises four cycles of basaltic-rhyolitic volcanism. Basaltic volcanism typically precedes rhyolitic volcanism in Cycles 1–3. Cycle 4 represents the waning stages of volcanism and is dominated by peritidal sediments and basaltic volcanics. A spectrum of eruptive and emplacement mechanisms is represented ranging from the Hawaiian and Strombolian-type volcanism of the basaltic flows and pyroclastic scoria deposits, to highly explosive sub-Plinian to Plinian rhyolitic pyroclastic eruptions forming pyroclastic density currents (PDC) and high grade rheomorphic ignimbrites. During this field trip we will examine key exposures illustrating this spectrum of eruptive and emplacement processes, and their diagnostic characteristics, along with evidence for the interaction between mafic and felsic magmas and a variety of peperitic breccias formed as a result of emplacement of flows on wet peritidal sediments. The constraints the depositional setting and voluminous bimodal volcanism places on tectonic models will also be considered.

References

  1. Baldwin, D., 1991, Physical volcanology, geochemistry, and depositional setting of the Siluro–Devonian volcanic rocks near St. Andrews, New Brunswick: Unpublished MSc Thesis, Acadia University, NS, 231 p.
  2. Bradley, D.C., Tucker, R.D., Lux, D.R., Harrris, A.G., and McGregor, D.C., 2000, Migration of the Acadian Orogen and foreland basin across the Northern Appalachians of Maine and adjacent areas: U.S. Geological Survey Professional Paper 1624, 55 p., https://doi.org/10.3133/pp1624.
  3. Branney, M.J., Bonnichsen, B., Andrews, G.D.M., Ellis, B., Barry, T.L. and McCurry, M., 2008, ‘Snake River (SR)-type’ volcanism at the Yellowstone hotspot track: Distinctive products from unusual, high-temperature silicic super-eruptions: Bulletin of Volcanology, v. 70, p. 293–314, https://doi.org/10.1007/s00445-007-0140-7.
  4. Brown. R.J., and Andrews, G.D.M., 2015, Deposits of pyroclastic density currents, in Sigurdsson, H., ed., The Encyclopedia of Volcanoes, 2nd edition: Elsevier, p. 631–648, https://doi.org/10.1016/B978-0-12-385938-9.00036-5.
  5. Brown, R.J., Branney, M.J., Maher, C., and Dávila-Harris, P., 2010, Origin of accretionary lapilli within ground-hugging density currents: Evidence from pyroclastic couplets on Tenerife: Geological Society of America Bulletin, v. 122, p. 305–320, https://doi.org/10.1130/B26449.1.
  6. Bryan, S.E., Peate, I.U., Peate, D.W., Self, S., Jerram, D.A., Mawby, M.R., Marsh, J.S., and Miller, J.A., 2010, The largest volcanic eruptions on Earth: Earth-Science Reviews, v. 102, p. 207–229, https://doi.org/10.1016/j.earscirev.2010.07.001.
  7. Churchill-Dickson, L., 2004, A Late Silurian (Pridolian) age for the Eastport Formation, Maine: A review of the fossil, stratigraphic, and radiometric-age data: Atlantic Geology, v. 40, p. 189–195, https://doi.org/10.4138/1038.
  8. Cimarelli, C., De Rita, D., Dolfi, D., and Procesi, M., 2008, Coeval strombolian and vulcanian-type explosive eruptions at Panarea (Aeolian Islands, Southern Italy): Journal of Volcanology and Geothermal Research, v. 177, p. 797–811, https://doi.org/10.1016/j.jvolgeores.2008.01.051.
  9. Dadd, K.A., and Van Wagoner, N.A., 2002, Magma composition and viscosity as controls on peperite texture: An example from Passamaquoddy Bay, southeastern Canada: Journal of Volcanology and Geothermal Research, v. 114, p. 63–80, https://doi.org/10.1016/S0377-0273(01)00288-8.
  10. Dostal, J., Wilson, R.A., and Keppie, J.D., 1989, Geochemistry of Siluro–Devonian Tobique volcanic belt in northern and central New Brunswick (Canada): tectonic implications: Canadian Journal of Earth Sciences, v. 26, p. 1282–1296, https://doi.org/10.1139/e89-108.
  11. Fyffe, L.R., and Fricker, A., 1987, Tectonostratigraphic terrane analysis of New Brunswick: Atlantic Geology, v. 23, p. 113–122.
  12. Fyffe, L.R., Pickerill, R.K., and Stringer, P., 1999, Stratigraphy, sedimentology and structure of the Oak Bay and Waweig formations, Mascarene Basin: Implications for the paleotectonic evolution of southwestern New Brunswick: Atlantic Geology, v. 35, p. 59–84, https://doi.org/10.4138/2024.
  13. Knott, T.R., Branney, M.J., Reichow, M.K., Finn, D.R., Coe, R.S., Storey, M., Barfod, D., and McCurry, M., 2016, Mid-Miocene record of large-scale Snake River-type explosive volcanism and associated subsidence on the Yellowstone hotspot track: The Cassia Formation of Idaho, USA: Geological Society of America Bulletin, v. 128, p. 1121–1146, https://doi.org/10.1130/B31324.1.
  14. Lodge, R.W.D., 2004, Volcanism of the Silurian Eastport Formation, Maine, U.S.A.: Atlantic Geology, v. 40, p. 259–260.
  15. Lodge, R.W.D., Van Wagoner, N.A., and Dadd, K.A., 2005, Phreatomagmatism of the Silurian Passamaquoddy Bay subbelt, Maine and New Brunswick: Atlantic Geology, v. 41, p. 70.
  16. McLaughlin, K.J., Barr, S.M., Hill, M.D., Thompson, M.D., Ramezani, J., and Reynolds, P.H., 2003, The Moosehorn Plutonic Suite, southeastern Maine and southwestern New Brunswick: Age, petrochemistry, and tectonic setting: Atlantic Geology, v. 39, p. 23–146, https://doi.org/10.4138/1176.
  17. McNeil, W., 1989, The physical volcanology and geochemistry of the eastern portion of the volcanic belt of Passamaquoddy Bay, southwestern New Brunswick: Unpublished MSc Thesis, Acadia University, NS, 197 p.
  18. Mohammadi, N., Fyffe, L.R., McFarlane, C.R.M., Wilson, R., and Lentz, D.R., 2019, U–Pb zircon and monazite geochronology of volcanic and plutonic rocks in southwestern, central, and northeastern New Brunswick: Geological Survey of Canada Open File 8581, 44 p.
  19. Pickerill, R.K., and Pajari Jr., G.E., 1976, The Eastport Formation (Lower Devonian) in the northern Passamaquoddy Bay area, southwest New Brunswick: Canadian Journal of Earth Sciences, v. 13, p. 266–270, https://doi.org/10.1139/e76-028.
  20. Piñán Llamas, A., and Hepburn, J.C., 2013, Geochemistry of Silurian–Devonian volcanic rocks in the Coastal Volcanic belt, Machias-Eastport area, Maine: Evidence for a pre-Acadian arc: Geological Society of America Bulletin, v. 125, p. 1930–1942, https://doi.org/10.1130/B30776.1.
  21. Rankin, D.W., and Tucker, R., 1995, U–Pb age of the Katahdin-Traveler igneous suite, Maine, local age of the Acadian orogeny, and thickness of Taconian crust (Abstract): Geological Society of America Abstracts with Programs, v. 27, no. 6, p. 224–225.
  22. Sánchez-Mora, D., McFarlane, C.R.M., Walker, J.A., and Lentz, D.R, 2021, Geochemistry and U–Pb geochronology of the Williams Brook area, Tobique–Chaleur zone, New Brunswick: Stratigraphic and geotectonic setting of gold mineralization: Canadian Journal of Earth Sciences, v. 58, p. 1040–1058, https://doi.org/10.1139/cjes-2020-0094.
  23. Seaman, S.J., Wobus, R.A., Wiebe, R.A., Lubick, N., and Bowring, S.A., 1995, Volcanic expression of bimodal magmatism: The Cranberry Island Series–Cadillac Mountain Complex, coastal Maine: The Journal of Geology, v. 103, p. 301–311, https://doi.org/10.1086/629748.
  24. Seaman, S.J., Scherer, E.E., Wobus, R.A., Zimmer, J.H., and Sales, J.G., 1999, Late Silurian volcanism in coastal Maine: The Cranberry Island series: Geological Society of America Bulletin, v. 111, p. 686–708, https://doi.org/10.1130/0016-7606(1999)111%3C0686:LSVICM%3E2.3.CO;2.
  25. Seaman, S.J., Hon, R., Whitman, M., Wobus, R.A., Hogan, J.P., Chapman, M., Koteas, G.C., Rankin , D., Piñán-Llamas, A., and Hepburn, J.C., 2019, Late Paleozoic supervolcano-scale eruptions in Maine, USA: Geological Society of America Bulletin, v. 131, p. 1995–2010, https://doi.org/10.1130/B32058.1.
  26. Turner, S., and Burrow, C.J., 2018, Microvertebrates from the Silurian–Devonian boundary beds of the Eastport Formation, Maine, eastern USA: Atlantic Geology, v. 54, p. 171–187, https://doi.org/10.4138/atlgeol.2018.006.
  27. Wilson, R.A., van Staal, C.R., and Kamo, S.L, 2017, Rapid transition from the salinic to Acadian orogenic cycles in the northern Appalachian Orogen: Evidence from northern New Brunswick, Canada: American Journal of Science, v. 317, p. 449–482, https://doi.org/10.2475/04.2017.02.
  28. van Staal, C.R., and Barr, S.M., 2012, Lithospheric architecture and tectonic evolution of the Canadian Appalachians and associated Atlantic margin, in Percival, J.A., Cook, F.A., and Clowes, R.M., eds., Tectonic Styles in Canada: The LITHOPROBE Perspective: Geological Association of Canada Special Paper, v. 49, p. 41–95.
  29. van Staal, C.R., Whalen, J.B., Valverde-Vaquero, P., Zagorevski, A., and Rogers, N., 2009, Pre-Carboniferous, episodic accretion-related, orogenesis along the Laurentian margin of the northern Appalachians: Geological Society, London, Special Publications, v. 327, p. 271–316. https://doi.org/10.1144/SP327.13.
  30. van Staal, C.R., Zagorevski, A., McNicoll, V.J., and Rogers, N., 2014, Time-transgressive Salinic and Acadian orogenesis, magmatism and old red sandstone sedimentation in Newfoundland: Geoscience Canada, v. 41, p. 138–164, https://doi.org/10.12789/geocanj.2014.41.031.
  31. Van Wagoner, N.A., and Dadd, K.A., 2003, A Silurian age for the Passamaquoddy Bay volcanic sequence in southwestern New Brunswick: implications for regional correlations (Abstract): Geological Society of America Abstracts with Programs v. 35, p. 79.
  32. Van Wagoner, N.A., McNeil, W., and Fay, V., 1988, Early Devonian bimodal volcanic rocks of southwestern New Brunswick: petrography, stratigraphy, and depositional setting: Atlantic Geology, v. 24, p. 301–319, https://doi.org/10.4138/1659.
  33. Van Wagoner, N.A., Dadd, K.A., Baldwin, D.K., McNeil, W., 1994, Physical volcanology, stratigraphy, and depositional setting of the Middle Paleozoic volcanic and sedimentary rocks of Passamaquoddy Bay, southwestern New Brunswick: Geological Survey of Canada Paper 91–14, 53 p., https://doi.org/10.4095/194486.
  34. Van Wagoner, N.A., Leybourne, M.I., Dadd, K.A., and Huskins, M.L.A., 2001, The Silurian(?) Passamaquoddy Bay mafic dyke swarm, New Brunswick: Petrogenesis and tectonic implications: Canadian Journal of Earth Sciences, v. 38, p. 1565–1578, https://doi.org/10.1139/cjes-38-11-1565.
  35. Van Wagoner, N.A., Leybourne, M.I., Dadd, K.A., Baldwin, D.K., and McNeil, W., 2002, Late Silurian bimodal volcanism of southwestern New Brunswick, Canada: Products of continental extension: Geological Society of America Bulletin, v. 114, p. 400–418, https://doi.org/10.1130/0016-7606(2002)114%3C0400:LSBVOS%3E2.0.CO;2.
  36. Van Wagoner, N.A., Lodge, R.W.D, and Dadd, K.A., 2005, Comparative volcanology of the Silurian Passamaquoddy Bay subbelt, Maine and New Brunswick: Implications for correlation and volcanic setting (Abstract): Geological Association of Canada–Mineralogical Association of Canada, Abstracts and Program, v. 30, p. 199–200.