Mackenzie igneous events, Canada: Middle Proterozoic hotspot magmatism associated with ocean opening

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

97

Scientific paper

U-Pb ages have been obtained for the Muskox intrusion and the Mackenzie dyke swarm. The age of a pyroxenite from the layered series of the intrusion is 1270 +/- 4 Ma. Baddeleyite fractions from four widely-spaced Mackenzie diabases define a single discordia line with an upper intercept age of 1267 +/- 2 Ma. The dyke age of 1267 Ma provides a precise time-marker for much of the northwestern Canadian Shield. Mackenzie intrusive events were coeval with eruption of Coppermine River flood basalts in the Coppermine homocline. The short time-span, large volume and specific focus of Mackenzie igneous events suggest that magmatism occurred above a large hotspot caused by the presence of a mantle plume. We infer that magmatism was initiated when rifting breached a large domal uplift supported by the plume-generated hotspot. The uplift-subsidence record in the Coppermine homocline is predicted by numerical models for rifting above hot asthenospheric mantle leading to ocean opening. An array of five large gravity anomalies north of the homocline may outline a region of stretched continental crust extensively intruded by Mackenzie mafic igneous bodies.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Mackenzie igneous events, Canada: Middle Proterozoic hotspot magmatism associated with ocean opening does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Mackenzie igneous events, Canada: Middle Proterozoic hotspot magmatism associated with ocean opening, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mackenzie igneous events, Canada: Middle Proterozoic hotspot magmatism associated with ocean opening will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1569503

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.