Vulcan structure explained

The Vulcan structure is a 350km (220miles) long major convergent boundary between the Medicine Hat Block and the Loverna Block, Archean basement rock structures which lie between the Wyoming craton and Hearne craton on the western edge of the North American craton.^{[1] [2]} It lies under the Western Canadian Sedimentary Basin.^[3]

The Vulcan structure has intrigued geologists because it is a region of low gravity and contains an east-trending magnetic anomaly which cuts across the magnetic field of southern Alberta at a high angle. The Vulcan structure was the target of one of the first deep-crustal seismic profiles in the late 1960s.^[4] Geologists have offered several explanations for what the structure is: failed Proterozoic rift, intraplate collision zone, Proterozoic suture, or continental collision zone.

Notes and References

1. Eaton, David W.; Ross, Gerald M.; and Clowes, Ronald M. "Seismic-Reflection and Potential-Field Studies of the Vulcan Structure, Western Canada: A Paleoproterozoic Pyrenees?" Journal of Geophysical Research. 104:B10 (1999).
2. Hope, Jacqueline and Eaton, David. "Crustal Structure Beneath the Western Canada Sedimentary Basin: Constraints From Gravity and Magnetic Modelling." Canadian Journal of Earth Sciences. 39:3 (2002).
3. Eaton, David; Ross, Gerald; Clowes, Ronald M.; and Cook, F.A. "Lithospheric Structure of the Southern Hearne Province, Canadian Shield: A Palaeoproterozoic Pyrenees?" LSPF Newsletter. 11:1 (December 1998).
4. For information generally on Deep Probe, see: Gorman, Andrew R.; Clowes, Ron M.; Ellis, Robert M.; Henstock, Timothy J.; Spence, George D.; Keller, G. Randy; Levander, Alan; Snelson, Catherine M.; Burianyk, Michael J.A.; Kansewich, Ernest R.; Asudeh, Isa; Hajnal, Zoltan; and Miller, Kate C. "Deep Probe: Imaging the Roots of Western North America." Canadian Journal of Earth Sciences. 39:3 (2002).