Thermal History of the Grenville Front Tectonic Zone, Central Ontario

Abstract

The Grenville Front marks the boundary between the ca. 1.2-1.0 Ga Grenville Province and its foreland. Abrupt increases in metamorphic grade across the Front in central Ontario, and pervasive high-strain Front-parallel fabric in the adjacent tectonic zone (GFTZ), imply that it accommodated substantial differential uplift relative to the foreland during the Grenville orogeny. Knowledge of the timing, duration, and significance of tectono-metamorphic events at the Front is fundamental to developing models of the evolution of the orogen.