Iapetus Suture
 | This article needs additional citations for verification. (April 2010) |
The Iapetus Suture is one of several major
Background
The
The closure of Iapetus involved a complex and protracted collisional history of numerous continental fragments, volcanic arcs and back-arc basins that were accreted to Laurentia and Avalonia between the Early Ordovician and Late Silurian. The notion of a single suture zone in a complex orogen such as the Appalachian/Caledonian is unrealistic as several temporal and spatial distinct suture zones are present.
In Canada
The Early Ordovician (Taconic)
In the United States
The suture runs through the north-eastern states of Maine, New Hampshire, Massachusetts and Connecticut. Rhode Island lies entirely to the east of the suture.[2]
In Ireland
The estuary of the River Shannon (Ireland's largest river) follows the line of the Iapetus suture on the west coast. The suture reaches the east coast at Clogherhead in County Louth. Ireland's crust (and sedimentary rocks) to the north-west of the suture originally derives from Laurentia (proto-North America), while the crust to the south-east is Avalonian ("European").[4]
On the Isle of Man (Niarbyl Fault)
The Niarbyl Fault is an exposed section of the Iapetus Suture as it crosses through the Irish Sea. It is readily visible in present-day Niarbyl on the southwest coast of Isle of Man. The fault is manifested by two major rock groups which abut each other, both deposited by their respective, aforementioned continents – the Manx Group to the south-east and the Dalby Group to the north-west.[5] The Niarbyl fault is evidence of two paleocontinents colliding: Avalonia on which present-day England is located and Laurentia which contains both present-day North America and Scotland.
The fault is visible close to the shoreline downhill from the Niarbyl Cafe and Visitor Centre in Niarbyl.
In Great Britain
The Caledonian orogeny united the northern and southern portions of present-day Great Britain. The Iapetus Suture runs from the Solway Firth to Lindisfarne.[6] The Anglo-Scottish border runs near and roughly parallel to the suture.
See also
- Plate tectonics – Movement of Earth's lithosphere
- Supercontinent cycle – Repeated joining and separation of Earth's continents
- Trans-European Suture Zone – Boundary between the East European Craton and the orogens of South-Western Europe
References
- ^ J. C. Pollock, D. H. C. Wilton, C. R. van Staal, and K. D. Morrissey U-Pb detrital zircon geochronological constraints on the Early Silurian collision of Ganderia and Laurentia along the Dog Bay Line: The terminal Iapetan suture in the Newfoundland Appalachians. Am J Sci, 1 February 2007; 307(2): 399–433
- ^ "Map". researchgate.net. Retrieved 27 November 2020.
- ^ Devoy, R., Cummins, V., Brunt, B., Bartlett, D., & Kandrot, S. (2021). The Coastal Atlas of Ireland (Illustrated edition). Cork University Press, page 106.
- ^ Baxter, Sadhbh. "A Geological Field Guide to Cooley, Gullion, Mourne & Slieve Croob" (PDF). Archived from the original (PDF) on 14 November 2017. Retrieved 8 November 2011.
- ^ Burnett, Dave; Guard, Charles; Quirk, Dave (2003). "Dalby Group". Manx Geological Survey. Retrieved 15 August 2009.
- ^ Hill, John (7 February 2007). "Palaeozoic History of the UK – Part 1: Cambrian to Silurian". GeologyRocks. Archived from the original on 23 March 2010. Retrieved 16 August 2009.