The mine is characterized by Keweenawan
rock and Kincaid breccia just north of the site, Baker noted.
Chapter 5, 'Breaking Up', takes us to Africa and our own origins, a 1698 'pygmy' on a ship in London, and the rifts where 'Africa is busily trying to tear itself apart'--possibly a modern analogy to the billion year old Keweenawan
rift in North America.
The Keweenawan Rift represents an ancient example of such collision-induced rifting.
Collision-induced rifting: The Grenville Orogeny and the Keweenawan rift of North America.
LaBerge (1997) suggests that the arsenopyrite may have been emplaced during igneous activity associated with the 1,100-million-year-old Keweenawan
mid-continent rift system.
085 Ga Keweenawan event [#17a] located at the southwest end of the swarm (next entry).
08 Ga: One of the most dramatic flood basalt events in Canada and the United States is arguably the Keweenawan magmatism [#17a] of the Mid-Continent Rift (e.
km of the Canadian Shield, to young flood basalts, such as the rift-related Keweenawan Group and the accreted oceanic plateau, Wrangellia, in the Cordillera.