Master of Science
The age of the youngest gold event at the Timmins West Mine is unknown. Scheelite geochemistry and geochronology at the TWM were constrained using WDS and EDS mapping, LA-ICPMS and MC-ICPMS analytical techniques. Trace element analyses by LA-ICPMS revealed scheelites mineralized from a common and oxidized fluid. Samarium-Neodymium isotopic analyses of 15 scheelite grains yielded a linear regression isochron with a corresponding age of 2587 +/- 49 Ma (MSWD = 2.5) and εNdi, calculated from CHUR, of 1.01 ± 0.11 (2SD). A second internal isochron from a single scheelite grain yielded an age of 2516 +/- 88 Ma (MSWD = 0.64). Strontium isotopic compositions of scheelites have 87Sr/86Sri at 2.6 Ga varying from 0.70116 to 0.70178, corresponding to εSri, calculated from CHUR, of -0.05 ± 3.97 (2SD). Scheelite formation, and possibly gold, at the TWM was late compared to magmatic intrusions in the southern Abitibi.
Van Kessel, Annika, "Trace element geochemistry and Nd-Sr isotope systematics of Scheelite from the Thunder Creek and 144 Gap deposits, Timmins, Ontario: implications for timing and genesis of gold" (2018). Electronic Thesis and Dissertation Repository. 5814.