U-PB GARNET AND TITANITE AGE FOR THE BRISTOL TOWNSHIP LAMPROPHYRE SUITE, WESTERN ABITIBI SUBPROVINCE, CANADA

A U-Pb age of 2687 +/- 3 Ma has been determined for a garnetite dike, using melanite garnet and titanite mineral separates. This is the first primary igneous U-Pb age reported using garnet. The garnetite dike is part of the Bristol Township lamprophyre suite, which is extremely enriched in large-ion lithophile elements and light rare earth elements and which is located within the Destor Porcupine fault zone of the western Abitibi Subprovince. The age represents an upper limit for late-stage gold mineralization found along brittle fractures that cut the lamprophyre suite and it coincides with regional transpression documented in several locations in the southern Superior Province.