Type metamorphic | Extent eastern Maryland | |
![]() | ||
The Port Deposit Gneiss is a Paleozoic gneiss formation in Harford County, Maryland. It is described as a "Moderately to strongly deformed intrusive complex, chiefly composed of quartz diorite gneiss. Rock types include gneissic biotite-quartz diorite, hornblende-biotite-quartz diorite, and biotite granodiorite, with minor amounts of quartz monzonite and hornblende-quartz diorite. Moderate protoclastic foliation grades into strong cataclastic shearing." It intrudes into the Volcanic Complex of Cecil County.
Quarrying
The Port Deposit Gneiss has been quarried along the west bank of the Susquehanna River for over 100 years.
Port Deposit Gneiss was used in:
References
Port Deposit Gneiss Wikipedia(Text) CC BY-SA