Preview
Contributing Institution
Maine Geological Survey
Document Type
Image
Identifier
72142
Description
Photo 6: Foliated, porphyritic biotite granodiorite of the South Pond Porphyry (Dsp) on the southern end of Hall Island. The porphyritic texture in this rock refers to the large cream-colored alkali feldspar minerals set in a finer grained, strongly foliated, dark-colored matrix rich in biotite, quartz, and feldspar. The preferred orientation of the large ovoid feldspar grains, the strongly foliated matrix, and pressure shadows of finer grained quartz and feldspar flanking the larger feldspars are suggestive of superimposed shear stresses. Hall Island, Friendship.
Project Name: STATEMAP Louds Island Bedrock24k
Exact Creation Date
7-28-2022
Location
Friendship
Supplemental Rights
Credit must be given to the photographer and the Maine Geological Survey when this photo is displayed, reproduced, distributed and/or used in derivative works.
Keywords
bedrock mapping; outcrop; STATEMAP; Louds Island