Nd isotope mapping of the Dysart gneiss complex: Evidence for a rifted block within the Central Metasedimentary Belt of the Grenville Province

More than 65 new Nd isotope analyses are presented for the vicinity of the Central Metasedimentary Belt Boundary Zone (CMBBZ) near Haliburton in the Grenville Province of Ontario, Canada. They fall into two well-defined groups, with distinct ranges of TDM model ages. These two groups comprise the CMBBZ with an average TDM age=1.46Ga, and rocks of the Central Metasedimentary Belt (CMB) with an average TDM age of 1.28Ga. However, a distinct block …