
            
            By: magic-gigapans
            
              Image: Chris Johnson, Mid-Atlantic Geo-Image Collection
                
            
            
              License:
                 Creative Commons Non Commercial ⧉
              
            
          
            Uploaded: 13 May 2020
            Last Updated: 15 May 2020
          
              374 megapixels
            23,208 x 16,116 pixels
            77.4 in X 53.7 in at 300dpi
            
              254 pixels per inch
          
This outcrop can be found along the Difficult Run Trail north of Georgetown Pike. The North. This is part of the Mather Gorge Formation. A proterozoic metagraywacke. This outcrop is an example of partial melting in action. As the graywacke underwent high grades of metamorphism some of the minerals (particularly quartz and feldspars) began to melt and reform. This migmatite and others like it are the result of tectonic collisions during the Taconic and Acadian Orogenies.