January 2025 LIP of the Month
The Paleoproterozoic Large Igneous Province (LIP) Record of Northern Canada
Kenneth L. Buchan1, Richard E. Ernst2
1 Geological Survey of Canada, Ottawa, Canada; kbuchan33@gmail.com;
2 Carleton University, Ottawa, Canada; Richard.Ernst@Carleton.ca
Large Igneous Provinces (LIPs) and their giant mafic dyke swarms play an important role in understanding the tectonic evolution of ancient continents and supercontinents (Ernst 2014; Buchan and Ernst 2021). This synthesis (extracted from Buchan and Ernst 2024) updates the information that was available for well-dated Paleoproterozoic dyke swarms and LIPs in northern Canada (e.g., Buchan and Ernst 2004), with an emphasis on their age, geographic distribution, paleomagnetism, and potential linkages to coeval magmatic events. Their tectonic settings, with a focus on links to rifting and continental breakup, are also discussed. Finally, the use of giant dyke swarms and LIPs for testing paleocontinental reconstructions is considered, based mainly on paleomagnetism or on matching coeval magmatic events or sequences of magmatic events (magmatic barcoding) between cratons. Full details on all these aspects are presented in Buchan and Ernst (2024). Figures 1-8 show the locations of the various Paleoproterozoic LIPs and LIP components.
Figure 1: Ca. 2.50-2.46 Ga LIP record (after Buchan and Ernst 2024)
Figure 2: Ca. 2.27-2.19 Ga LIP record (after Buchan and Ernst 2024)
Figure 3: Ca. 2.13-2.11 Ga LIP record (after Buchan and Ernst 2024)
Figure 4: Ca. 2.05-2.01 Ga LIP record (after Buchan and Ernst 2024)
Figure 5: Ca. 1.97-1.95 Ga LIP record (after Buchan and Ernst 2024)
Figure 6: Ca. 1.93-1.91 Ga LIP record (after Buchan and Ernst 2024)
Figure 7: Ca. 1.92-1.84 Ga LIP record (after Buchan and Ernst 2024)
Figure 8: Ca. 1.83-1.82 Ga LIP record (after Buchan and Ernst 2024)
References
Buchan, K.L., Ernst, R.E. (2004) Diabase dyke swarms and related units in Canada and adjacent regions. Geological Survey of Canada Map No. 2022A, scale 1:5,000,000, with accompanying booklet.
Buchan, K.L., Ernst, R.E. (2021) Plumbing systems of large igneous provinces (LIPs) on Earth and Venus: Investigating the role of giant circumferential and radiating dyke swarms, coronae and novae, and mid-crustal intrusive complexes, Gondwana Research, v. 100, p. 25-43. https://doi.org/10.1016/j.gr.2021.02.014
Buchan, K.L., Ernst, R.E. (2024) Paleoproterozoic dyke swarms and large igneous provinces of northern Canada and their use in understanding extension, rifting, and paleocontinental reconstructions. In: S.J. Pehrsson, N. Wodicka, N. Rogers, and J.A. Percival (eds.) Canada’s Northern Shield: New Perspectives from the Geo-Mapping for Energy and Minerals Program. Geological Survey of Canada, Bulletin 612, p. 375–410. https://doi.org/10.4095/332506
Ernst, R.E. (2014) Large Igneous Provinces. Cambridge University Press. 653 p.