Paleoproterozoic Granite or Mesoproterozoic Batholith?: Petrographic and Geochronologic Study of the Albany Granite of the Medicine Bow Mountains, Southeastern WY
presentationposted on 07.08.2014, 00:00 by Lauren Harrison
The Albany Granite is a highly ferroan potassium-rich granite that has been associated with both a 1.75 Ga event of magmatism in the Sierra Madre Mountains as well as widespread 1.4 Ga magmatism that took place from southeastern California to northeastern Canada. The amount of time separating these events suggests that the Albany Granite cannot logically be associated with both although it has been dated to correlate with each. Therefore, the purpose of this research project is to resolve this petrologic/geochronologic conundrum and evaluate the tectonic implications of the emplacement and deformation of the Albany Granite based on an extensive new data set derived from field-based studies, petrography, geochemical analysis and U-Pb geochronology. Initial results indicate that the Albany Granite is ~1.4 Ga and thus is most likely a western outcrop of the Sherman Granite. This result has implications for the intrusive system present at 1.4 Ga in the region, the extent of the Sherman Batholith, and the first evidence of a 1.4 Ga deformational event that extends as far north as Wyoming.