Geologic notes on Granite Mountain, Mount Hayes D-3 Quadrangle, Alaska

In 2006-2007, Alaska Division of Geological & Geophysical Surveys (DGGS) geologists traversed and collected rock samples from ridges on the north side of Granite Mountain in the Mount Hayes D-3 Quadrangle to supplement existing literature with additional details about the variations in texture, lithology and orientation of the 'Granite of Granite Mountain' (map unit grgm) described by Nokleberg and others (1992). The digital data files for this report provide station locations and observations recorded in the geologists' field notes. Outcrop observations describe fine- to medium-grained granodiorite and medium- to coarse-grained tonalite units which appear to be in contact with each other on the ridges north of Granite Mountain. Mafic enclaves are common; mafic and felsic dikes transect the plutonic rocks. Slices of quartzite are either in faulted or intrusive contact within the pluton.