Abstract
Rb-Sr isotopic investigations of the rock-types within the Morin anorthosite complex, Quebec, suggest that: 1. both the mangerites and the leuconorites and anorthosites within this complex crystallized with a range of 87Sr/86Sr ratios, and 2. at least some of the mangerites crystallized approximately 100 m.y. after the anorthosites and leuconorites. From this evidence, it is argued that a number of magma sources gave rise to the melts that formed these rocks and that some local hybridization of these melts also took place by assimilation of other rock types. This same pattern is found in the Adirondack and Nain Complexes.
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Barton, J.M., Doig, R. Sr-isotopic studies of the origin of the Morin anorthosite complex, Quebec, Canada. Contr. Mineral. and Petrol. 61, 219–230 (1977). https://doi.org/10.1007/BF00376697
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DOI: https://doi.org/10.1007/BF00376697